On the Importance of Searching for \\ Oscillations of the Jovian Inner Radiation\\ Belt with a Quasi-Period of 40 Minutes
Yu-Qing Lou$^{!\ \dagger\ *}$ and Chen Zheng$^{\dagger}$
$^{\dagger}$Physics Department
Tsinghua Center for Astrophysics
Beijing 100084
China
$^{!}$National Astronomical Observatories
Chinese Academy of Sciences
A20
Datun Road
Beijing
100012 China
$^{*}$Department of Astronomy and Astrophysics
Chicago
Illinois 60637 USA
Experiments aboard the Ulysses spacecraft discovered quasi-periodic bursts of relativistic electrons and of radio emissions with $\sim 40-$minute period (QP-40) from the south pole of Jupiter %during the two-week Jovian encounter in February 1992. Such polar QP-40 burst activities were found to correlate well with arrivals of high-speed solar winds at Jupiter. %as Ulysses traveled towards the Sun in the southern heliosphere. We advance the physical scenario that the inner radiation belt (IRB) within $\sim 2-3$ Jupiter's radius $R_J$, where relativistic electrons are known to be trapped via synchrotron emissions, can execute global QP-40 magnetoinertial oscillations excited by arrivals of high-speed solar winds. Modulated by such QP-40 IRB oscillations, relativistic electrons trapped in the IRB may escape from the magnetic circumpolar regions during a certain phase of each 40-min period to form circumpolar QP-40 electron bursts. Highly beamed synchrotron emissions from such QP-40 burst electrons with small pitch angles relative to Jovian magnetic fields at $\sim 30-40R_J$ give rise to QP-40 radio bursts with typical frequencies $\lsim 0.2$MHz. We predict that the synchrotron brightness of the IRB should vary on QP-40 timescales upon arrivals of high-speed solar winds with estimated magnitudes $\gsim 0.1$Jy, detectable by ground-based radio telescopes. The recent discovery of $\sim 45$-min pulsations of Jupiter's polar X-ray hot spot by the High-Resolution Camera (HRC) of the Chandra spacecraft provides a strong supporting circumstantial evidence that the IRB neighborhood did oscillate with QP-40 timescales. Using the real-time solar wind data from the spacecraft Advanced Composition Explorer (ACE), we show here that such QP-40 pulsations of Jupiter's polar X-ray hot spot did in fact coincide with the arrival of high-speed solar wind at Jupiter. We note also that a properly sampled data of simultaneous far-ultraviolet images of auroral ovals obtained by the Hubble Space Telescope imaging spectrograph (HST-STIS) would have contained QP-40 oscillatory signatures. By our theoretical analysis, we offer several predictions that can be tested by further observations.
astro-ph0307276.tex
==============================
\documentstyle{mn}
\newif\ifAMStwofonts
%\AMStwofontstrue

%%%%% AUTHORS - PLACE YOUR OWN MACROS HERE %%%%%
\font\eightrm=cmr8 scaled 1000
\def\gsim{\;\lower4pt\hbox{${\buildrel\displaystyle >\over\sim}$}\;}
\def\lsim{\;\lower4pt\hbox{${\buildrel\displaystyle <\over\sim}$}\;}
\def\grls{\;\lower4pt\hbox{${\buildrel\displaystyle >\over <}$}\;}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\ifoldfss
  %
  \newcommand{\rmn}[1] {{\rm #1}}
  \newcommand{\itl}[1] {{\it #1}}
  \newcommand{\bld}[1] {{\bf #1}}
  %
  \ifCUPmtlplainloaded \else
    \NewTextAlphabet{textbfit} {cmbxti10} {}
    \NewTextAlphabet{textbfss} {cmssbx10} {}
    \NewMathAlphabet{mathbfit} {cmbxti10} {} % for math mode
    \NewMathAlphabet{mathbfss} {cmssbx10} {} %  "   "    "
  \fi
  %
  \ifAMStwofonts
  %
    \ifCUPmtlplainloaded \else
      \NewSymbolFont{upmath} {eurm10}
      \NewSymbolFont{AMSa} {msam10}
      \NewMathSymbol{\upi}     {0}{upmath}{19}
      \NewMathSymbol{\umu}     {0}{upmath}{16}
      \NewMathSymbol{\upartial}{0}{upmath}{40}
      \NewMathSymbol{\leqslant}{3}{AMSa}{36}
      \NewMathSymbol{\geqslant}{3}{AMSa}{3E}
      \let\oldle=\le     \let\oldleq=\leq
      \let\oldge=\ge     \let\oldgeq=\geq
      \let\leq=\leqslant \let\le=\leqslant
      \let\geq=\geqslant \let\ge=\geqslant
    \fi
    %
  \fi
%
\fi % End of OFSS

\ifnfssone
  %
  \newmathalphabet{\mathit}
  \addtoversion{normal}{\mathit}{cmr}{m}{it}
  \addtoversion{bold}{\mathit}{cmr}{bx}{it}
  %
  \newcommand{\rmn}[1] {\mathrm{#1}}
  \newcommand{\itl}[1] {\mathit{#1}}
  \newcommand{\bld}[1] {\mathbf{#1}}
  %
  \def\textbfit{\protect\txtbfit}
  \def\textbfss{\protect\txtbfss}
  \long\def\txtbfit#1{{\fontfamily{cmr}\fontseries{bx}\fontshape{it}%
    \selectfont #1}}
  \long\def\txtbfss#1{{\fontfamily{cmss}\fontseries{bx}\fontshape{n}%
    \selectfont #1}}
  %
  \newmathalphabet{\mathbfit} % math mode version of \textbfit{..}
  \addtoversion{normal}{\mathbfit}{cmr}{bx}{it}
  \addtoversion{bold}{\mathbfit}{cmr}{bx}{it}
  %
  \newmathalphabet{\mathbfss} % math mode version of \textbfss{..}
  \addtoversion{normal}{\mathbfss}{cmss}{bx}{n}
  \addtoversion{bold}{\mathbfss}{cmss}{bx}{n}
  %
  \ifAMStwofonts
    %
    \ifCUPmtlplainloaded \else
      %
      % Make NFSS 1 use the extra sizes available for bold math italic and
      % bold math symbol. These definitions may already be loaded if your
      % NFSS format was built with fontdef.max.
      %
      \UseAMStwoboldmath
      %
      \makeatletter
      \new@mathgroup\upmath@group
      \define@mathgroup\mv@normal\upmath@group{eur}{m}{n}
      \define@mathgroup\mv@bold\upmath@group{eur}{b}{n}
      \edef\UPM{\hexnumber\upmath@group}
      %
      \new@mathgroup\amsa@group
      \define@mathgroup\mv@normal\amsa@group{msa}{m}{n}
      \define@mathgroup\mv@bold\amsa@group{msa}{m}{n}
      \edef\AMSa{\hexnumber\amsa@group}
      \makeatother
      %
      \mathchardef\upi="0\UPM19
      \mathchardef\umu="0\UPM16
      \mathchardef\upartial="0\UPM40
      \mathchardef\leqslant="3\AMSa36
      \mathchardef\geqslant="3\AMSa3E
      %
      \let\oldle=\le     \let\oldleq=\leq
      \let\oldge=\ge     \let\oldgeq=\geq
      \let\leq=\leqslant \let\le=\leqslant
      \let\geq=\geqslant \let\ge=\geqslant
      %
    \fi
  \fi
  %
\fi % End of NFSS release 1

\ifnfsstwo
  %
  \newcommand{\rmn}[1] {\mathrm{#1}}
  \newcommand{\itl}[1] {\mathit{#1}}
  \newcommand{\bld}[1] {\mathbf{#1}}
  %
  \def\textbfit{\protect\txtbfit}
  \def\textbfss{\protect\txtbfss}
  \long\def\txtbfit#1{{\fontfamily{cmr}\fontseries{bx}\fontshape{it}%
    \selectfont #1}}
  \long\def\txtbfss#1{{\fontfamily{cmss}\fontseries{bx}\fontshape{n}%
    \selectfont #1}}
  %
  \DeclareMathAlphabet{\mathbfit}{OT1}{cmr}{bx}{it}
  \SetMathAlphabet\mathbfit{bold}{OT1}{cmr}{bx}{it}
  \DeclareMathAlphabet{\mathbfss}{OT1}{cmss}{bx}{n}
  \SetMathAlphabet\mathbfss{bold}{OT1}{cmss}{bx}{n}
  %
  \ifAMStwofonts
    %
    \ifCUPmtlplainloaded \else
      \DeclareSymbolFont{UPM}{U}{eur}{m}{n}
      \SetSymbolFont{UPM}{bold}{U}{eur}{b}{n}
      \DeclareSymbolFont{AMSa}{U}{msa}{m}{n}
      \DeclareMathSymbol{\upi}{0}{UPM}{"19}
      \DeclareMathSymbol{\umu}{0}{UPM}{"16}
      \DeclareMathSymbol{\upartial}{0}{UPM}{"40}
      \DeclareMathSymbol{\leqslant}{3}{AMSa}{"36}
      \DeclareMathSymbol{\geqslant}{3}{AMSa}{"3E}
      %
      \let\oldle=\le     \let\oldleq=\leq
      \let\oldge=\ge     \let\oldgeq=\geq
      \let\leq=\leqslant \let\le=\leqslant
      \let\geq=\geqslant \let\ge=\geqslant
      %
    \fi
  \fi
  %
\fi % End of NFSS release 2

\ifCUPmtlplainloaded \else
  \ifAMStwofonts \else % If no AMS fonts
    \def\upi{\pi}
    \def\umu{\mu}
    \def\upartial{\partial}
  \fi
\fi

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\title[Jupiter's QP-40 Polar Burst Activities]
{On the Importance of Searching for \\
Oscillations of the Jovian Inner Radiation\\
Belt with a Quasi-Period of 40 Minutes}
%Circumpolar Burst Activities of Jupiter\\ 
%with Quasi-Periods around 40 Minutes}

\author[Lou and Zheng]
{
Yu-Qing Lou$^{!\ \dagger\ *}$
and Chen Zheng$^{\dagger}$\\
$^{\dagger}$Physics Department, Tsinghua Center for Astrophysics, 
Tsinghua University, Beijing 100084, China\\ 
$^{!}$National Astronomical Observatories,
Chinese Academy of Sciences, A20, Datun Road, 
Beijing, 100012 China\\  
$^{*}$Department of Astronomy and Astrophysics, 
The University of Chicago,
Chicago, Illinois 60637 USA  }
%
%August 16, 2002 Chicago preparation for MNRAS Lett.
%an email sent to Linda Rowan of Science
%August 18, 2002 Chicago;
%January 21, 2003 Beijing THCA
%January 24, 2003 Beijing THCA manuscript number: MD40L
%June 25, 2003 referee report received.
%June 26, 2003 Beijing THCA manuscript number: MD40L
%June 27, 2003 (Friday) Beijing THCA manuscript number: MD40L
%July 9, 2003 (Wednesday) accepted as a Letter in MNRAS
%  see email shales01.acpt
%Reference in astro-ph system: astro-ph/0307232

\date{Accepted ....
      Received ...;
      in original form ...}
\pagerange{\pageref{firstpage}--\pageref{lastpage}}

\pubyear{2003}

\begin{document}

\maketitle

\label{firstpage}

\begin{abstract}
Experiments aboard the Ulysses spacecraft discovered quasi-periodic 
bursts of relativistic electrons and of radio emissions with 
$\sim 40-$minute period (QP-40) from the south pole of Jupiter 
%during the two-week Jovian encounter 
in February 1992. Such polar QP-40 burst activities were found to 
correlate well with arrivals of high-speed solar winds at Jupiter.
%as Ulysses traveled towards the Sun in the southern heliosphere. 
We advance the physical scenario that the inner radiation belt (IRB) 
within $\sim 2-3$ Jupiter's radius $R_J$, where 
relativistic electrons are known to be trapped via synchrotron 
emissions, can execute global QP-40 magnetoinertial oscillations 
excited by arrivals of high-speed solar winds. Modulated by such 
QP-40 IRB oscillations, relativistic electrons trapped in the IRB 
may escape from the magnetic circumpolar regions during a certain 
phase of each 40-min period to form circumpolar QP-40 electron 
bursts. Highly beamed synchrotron emissions from such QP-40 burst 
electrons with small pitch angles relative to Jovian magnetic fields 
at $\sim 30-40R_J$ give rise to QP-40 radio bursts with typical 
frequencies $\lsim 0.2$MHz. We predict that the synchrotron 
brightness of the IRB should vary on QP-40 timescales upon arrivals 
of high-speed solar winds with estimated magnitudes $\gsim 0.1$Jy, 
detectable by ground-based radio telescopes. The recent discovery 
of $\sim 45$-min pulsations of Jupiter's polar X-ray hot spot by 
the High-Resolution Camera (HRC) of the Chandra spacecraft provides 
a strong supporting circumstantial evidence that the IRB neighborhood 
did oscillate with QP-40 timescales. Using the real-time solar wind 
data from the spacecraft Advanced Composition Explorer (ACE), we show 
here that such QP-40 pulsations of Jupiter's polar X-ray 
hot spot did in fact coincide with the arrival of high-speed solar wind 
at Jupiter. We note also that a properly sampled data of simultaneous 
far-ultraviolet images of auroral ovals obtained by the Hubble Space 
Telescope imaging spectrograph (HST-STIS) would have contained QP-40 
oscillatory signatures. By our theoretical analysis, we offer several 
predictions that can be tested by further observations.
\end{abstract}

\begin{keywords} inner radiation belt ---
Jupiter --- magnetohydrodynamics --- oscillations
--- solar wind --- synchrotron emissions
\end{keywords}

\section{Introduction}

Quasi-periodic bursts of relativistic electrons 
(Simpson et al. 1992; McKibben et al.
%, Simpson \& Zhang 
1993; Desch 1994) and of accompanied radio emissions (MacDowall et al. 
1993) were discovered by the Ulysses spacecraft a decade ago. The burst 
electron energy ranges from a few to $\gsim 10$ MeV and the frequency 
of radio bursts is usually $\lsim 200$ kHz with occasional rises to 
$\sim 700$ kHz. These burst activities, characterized by a quasi-period 
of 40 minutes (QP-40), were inferred to occur in the south polar 
direction of Jupiter and were found to closely correlate with arrivals 
of high-speed solar winds at Jupiter (see figs. 11 and 12 of MacDowall 
et al. 1993; Bame et al. 1992). Polarizations of these radio bursts 
are predominantly right-handed. There were other evidence, though less 
certain, for Jovian QP-40 phenomena such as magnetic field fluctuations 
and proton fluxes from observations of various spacecraft 
(e.g., Balogh et al. 1992; Schardt et al.
%, McDonald \& Trainor 
1981).

Based on a theoretical magnetohydrodynamic (MHD) analysis, we 
proposed (Lou 2001) that the underlying physical mechanism 
may involve global QP-40 magnetoinertial oscillations of 
Jupiter's inner radiation belt (IRB) within $\sim 2-3R_J$. 
In the scenario of QP-40 IRB oscillations, several seemingly 
disparate key phenomena can be plausibly linked together. 
%It appears crucial to observationally search for QP-40 IRB 
%synchrotron brightness variations upon arrivals of high-speed 
%solar winds at Jupiter using ground-based radio telescopes.
%
%In terms of solar-Jovian interactions, one major goal has been 
%to understand the role of solar wind in producing Jovian transients 
%or variations and identify the physics involved. The recent Chandra, 
%Hubble Space Telescope (HST), and Galileo campaigns in support of 
%the Cassini fly-by were to search for transient auroral variations 
%that might be caused by the interaction of the solar wind with 
%Jupiter's magnetosphere (e.g., Gurnett et al. 2002). As parameters 
%of Jupiter and Earth are different, the studies of solar-terrestrial
%and solar-Jovian interactions are complementary to each other. In 
%broader contexts of astrophysics , the interaction between a 
%magnetized wind from a companion star and the magnetosphere of a 
%pulsar in a binary pulsar system may exhibit a wide range of 
%parameter regimes for us to explore novel physical effects. In this 
%perspective, the solar-Jovian interaction system offers a unique 
%space laboratory to test our physical understanding.
%
Variabilities from weeks to years of the Jovian system have been 
searched for in response to solar wind variations (e.g., Bolton 
et al. 1989; Miyoshi et al. 1999). The central question posed here 
is whether the synchrotron brightness of the IRB varies on QP-40 
timescales and shorter ones resulting from solar wind speed 
variations at Jupiter. 
%In this Letter, we show that physical reasonings along independent 
%lines based on multiwavelength observations of various Jovian QP-40 
%phenomena using different diagnostics have pinpointed such a 
%possibility (Lou 2001). 

The recent Chandra observations (Gladstone et al. 2002) detected 
QP-40 pulsations of north polar X-ray hot spots on Jupiter. 
From space, Cassini synchrotron radio observations at 2.2cm 
(Bolton et al. 2002) revealed relativistic electrons with energies 
$\gsim 50$ MeV inside the IRB. These observations provide a 
circumstantial evidence for QP-40 IRB oscillations. In this Letter, 
we derive physical consequences from empirical facts, provide 
relevant estimates, propose further observational tests, and 
establish that $\sim 45-$min pulsations of Jupiter's polar X-ray 
hot spot did coincide with an arrival of high-speed solar wind at 
Jupiter using the data from the spacecraft Advanced Composition 
Explorer (ACE). It would be significant to actively search for 
QP-40 IRB synchrotron brightness variations upon arrivals of 
high-speed solar winds at Jupiter using ground-based radio 
telescope facilities. Once established, this would enable us 
to study the dynamics of the IRB both observationally and 
theoretically from a new perspective.

\section{The Physical Scenario}

By tracing QP-40 radio burst directions (MacDowall et al. 1993) 
in the plane of sky, comparing arrival times of various 
energetic particle species (Zhang et al. 1995), and analyzing 
electron anisotropies (Zhang et al. 1993), it is fairly certain 
that these charged particles bursted from Jupiter's south 
magnetic polar region. Jupiter has long been known to be an 
important source of relativistic electrons populating the 
heliosphere (Simpson et al. 1975; Nishida 1976). While specific 
aspects remain to be understood, the Jovian magnetospheric system 
interacting with the solar wind  appears to be capable of producing 
relativistic electrons to supply the IRB and to compensate magnetic 
polar leaks.

What is then the origin or source of such polar QP-40 bursts 
of relativistic electrons and ions? By all accounts, it is 
plausible (Lou 2001) that QP-40 burst electrons and ions leak out 
from the narrow circumpolar zone separating the magnetic polar
region with open magnetic fields from the adjacent Jovian IRB with 
closed magnetic fields. 
%(e.g., Schultz \& Lanzerotti 1974; Coroniti 1975; Nishida 1976) 
The IRB can trap relativistic electrons with energies up to 
$\sim 50$MeV or higher, as inferred from IRB synchrotron emissions 
with wavelengths of $\sim 2.2-90$ cm (Bolton et al. 2002; de Pater
1984; Roberts et al. 1984; Sault et al. 1997).
Moreover, by combined effects of Jupiter's fast rotation with a
$\sim 10$-hour period and a strong dipole magnetic field with 
a polar surface strength $|\vec B|$ of $\sim 10-14.4$G, the 
IRB is capable of magnetoinertial oscillations with periods of 
$\sim 40-50$ minutes and shorter ones (Lou 2001). 

Such magnetoinertial oscillations of a rotating IRB involve both 
Lorentz and Coriolis forces. For low-frequency and large-scale 
oscillations, the mode frequency is hybrid of Alfv\'en and rotation 
frequencies; for high-frequency and small-scale oscillations, the 
mode frequencies are essentially those of globally trapped fast MHD 
waves. For the hybrid mode of the lowest frequency, the IRB plasma 
swings to and fro about the rotation axis.

With this scenario in mind, the gross overall correlations among 
QP-40 bursts of radio emissions (MacDowall et al. 1993), of 
relativistic electrons (Simpson et al. 1992; McKibben et al. 1993), 
of protons, and occasionally, of alphas (Zhang et al. 1995) seems 
to indicate that
(i) QP-40 polar electron bursts are most likely
%may be physically 
responsible for QP-40 polar radio bursts, and
(ii) a global resonant oscillatory mechanism may underlie 
the quasi-periodicity of $\sim 40$ min for polar bursts 
of relativistic electrons and ions (Schardt et al. 1981; 
Zhang et al. 1995).

To relate QP-40 IRB oscillations and QP-40 circumpolar bursts of 
electrons, we invoke large-scale asymmetries as well as small-scale 
irregulaties in magnetic field structures of the IRB (Lou 2001). 
During a certain phase of each IRB pulsation period, relativistic 
electrons may drift across thin vulnerable layers randomly 
spreading along circumpolar magnetic footpoints with a 
perpendicular gradient drift speed 
$\dot{\vec {\cal R}_{\perp}}=-m_e\gamma v_{\perp}^2c\vec B
\times\nabla |\vec B|/(2eB^3)$ into a narrow circumpolar strip and thus
give rise to an electron burst, where $m_e$ is the electron mass, 
$\gamma$ is the Lorentz factor, $v_{\perp}$ is the electron velocity
perpendicular to $\vec B$, $c$ is the speed of light, and $e$ is the
electron charge. Hence, QP-40 IRB oscillations lead to QP-40 
bursts of relativistic electrons and ions from magnetic circumpolar
zones. QP-40 radio bursts are then produced by highly beamed
synchrotron radio emissions from such escaped relativistic 
electrons with very small pitch angles $\alpha$ (e.g., 
$\alpha\sim 6-4\times 10^{-3}$ at $\sim 30-40R_J$) relative 
to magnetic field lines such that radio burst frequencies are 
typically $\lsim 200$ kHz detected by Ulysses (MacDowall 2001). 
%For example, $\alpha\sim 6-4\times 10^{-3}$ at $\sim 30-40R_J$.
%where $R_J\cong 7.14\times 10^9$cm is the Jupiter's radius).
It requires relativistic electrons of higher $\gamma$ to produce 
occasional rising frequencies of up to $\sim 700$ kHz at Ulysses.
That onsets of QP-40 radio bursts (McKibben et al. 1993; Desch 1994) 
sometimes precede relevant electron bursts by $\sim 4-8$ min are 
likely caused by radio emissions from those relativistic electrons 
that travel along neighboring magnetic field lines but that are not 
intercepted by Ulysses (Lou 2001). Admittedly, we do not yet know 
details of circumpolar electron leak processes by lacking clues 
of magnetic field inhomogeneities and irregularities or defects. 
%Empirically, the typical electron burst profile 
%with a sharp rise and a relatively slow falloff 
%would constrain any circumpolar leakage model.

\section{Theoretical Considerations}

In reference to observations, we now provide 
theoretical analyses and corresponding predictions.

\subsection{Excitations of Global IRB Oscillations}

Empirically, onsets of enhanced QP-40 burst activities correlate 
well with arrivals of high-speed solar winds at Jupiter (MacDowall 
et al. 1993). While the solar wind mass flux remains roughly 
constant for either fast or slow winds, variations in the wind 
speed $U$ ($\sim 800-400{\hbox{ km s}^{-1}}$) cause the radial 
size of the sunward magnetosphere to change drastically 
($\sim 50-100R_J$), where $R_J\cong 7.14\times 10^9$ cm.
%is Jupiter's radius. 
This offers a valuable clue for the 
excitation of QP-40 IRB oscillations and thus for the observed 
correlation of QP-40 polar burst activities with high-speed 
solar winds. Drastic changes of solar wind speed at the Jovian 
magnetosphere or persistent Jovian magnetospheric compressions 
sustained during a high-speed solar wind phase with irregular 
intermittent relaxations caused by wind speed variations can 
both resonantly drive QP-40 magnetoinertial IRB pulsations and 
induce neighboring magnetic field oscillations (Balogh et al. 
1992)
%; Schardt et al. 1981) 
through the conservation of the magnetospheric angular 
momentum (Nishida \& Watanabe 1981). Such MHD pulsations of 
the IRB should then lead to QP-40 brightness variations.

\subsection{Estimates for IRB Brightness Variations}

%To estimate the magnitude of IRB brightness variations, we note that 
The solar wind mass flux is estimated by
$4\pi\rho U D_J^2$,
%remains approximately constant for fast and slow solar winds, 
where $\rho$ is the wind mass density and $D_J$ is 
Jupiter's distance to the Sun. Changing from slow to 
fast winds at Jupiter,
%the radial size of the sunward magnetosphere 
%varies from $\sim 100 R_J$ to $\sim 50 R_J$ and
the wind ram pressure $\rho U^2$ increases by a factor of $\sim 2$.
%where $R_J\cong 7.14\times 10^9$cm is the Jupiter's radius.
After a transient time of adjustment and for a negligible IRB 
thermal pressure, this increase of wind ram pressure is grossly
balanced by an increase of magnetic pressure $B^2/(8\pi)$ of 
the IRB temporarily. Thus, the relative field strength variation 
$\delta B/B$ in the IRB may be as large as $\sim 40\%$ stirred 
by drastic solar wind speed variations; and by the magnetic flux 
conservation, the radial extent of the IRB may vary by 
$\sim 20\%$ accordingly. 
%Note such disturbances are quite nonlinear.

In the IRB, for a power-law distribution of electron number 
density $N(\gamma)\propto\gamma^{-S}d\gamma$ in the energy interval
$(\gamma, \gamma+d\gamma)$, the spectral intensity $I_{\nu}$ of 
radiation is $I_{\nu}\propto B^{(S+1)/2}\nu^{-(S-1)/2}$
(Ginzburg \& Syrovatskii 1965; Rybicki \& Lightman 1979). At a given 
frequency $\nu$, one has $\delta I_{\nu}/I_{\nu}\cong (S+1)\delta B/(2B)$. 
For the Jovian IRB, the spectral index $S>1$ and $I_{\nu}$ takes on 
values of $\sim 0.44\pm 0.15$, $\sim 3$, $\sim 4.02\pm 0.08$, and 
$\sim 5.15\pm 0.7$Jy at $\nu=13.8$, 5, 2.3, and 0.333 GHz, respectively 
(Bolton et al. 2002). Thus, in two separate frequency ranges $0.333-5$GHz 
and $5-13.8$GHz, $(S-1)/2\sim 0.19$ and $\sim 1.9$, respectively. 
Conservatively, $\delta I_{\nu}$ is estimated to be $\gsim 0.1$Jy. As 
a crucial test, such QP-40 IRB brightness variations in wavelengths 
$\sim 6-90$ cm should be searched for using ground-based radio telescopes. 
%Another point is that the strong magnetospheric disturbances 
%caused by the arrival of high-speed solar wind and variations 
%embedded therein can give rise to electric field and charge 
%imbalance within the IRB. There may be transient accelerations 
%of relativistic electrons within the IRB to quickly maintain a 
%quasi charge neutrality. Thus, additional relativistic electrons 
%may be generated within the IRB to track QP-40 time variations.

\subsection{Polarization Properties of Radio Bursts}

There are several physical reasons and observational tests 
to support and to further check our scenario. The radiation 
electric field $\vec E_{rad}$ from an accelerating electric 
charge $q$ is given by (e.g., Rybicki \& Lightman 1979)
$$
\vec E_{rad}(\vec r, t)={q\over c}\bigg[{\vec n\over\kappa^3R}
\times\{(\vec n-\vec\beta)\times \dot{\vec\beta\}}\bigg]\ ,
\eqno(1)
$$
where brackets denote variables at retarded times,
%$q$ is the electric charge, $c$ is the speed of light,
$\vec\beta\equiv \vec u/c$ is the particle velocity normalized by
$c$, $\dot{\vec\beta}$ is the time derivative of $\vec\beta$,
$\vec n$ is the unit vector along the line of sight distance $R$ 
at retarded times, and $\kappa\equiv 1-\vec n\cdot\vec\beta$.
%$R$ is the distance from the charge at the retarded time.
The radiation magnetic field is $\vec B_{rad}(\vec r, t)\equiv 
[\vec n\times\vec E_{rad}(\vec r, t)]$. The south polar magnetic 
field $\vec B$ points towards the Jupiter. For a relativistic 
electron streaming outward from the south pole with a small pitch 
angle $\alpha$ (nearly anti-parallel to $\vec B$), the instantaneous 
$\vec E_{rad}$ is nearly along $\dot{\vec\beta}$. Given an 
electron's right-hand gyration with respect to $\vec B$, the radio 
polarization at Ulysses should be right-handed; this qualitative 
conclusion has also been confirmed by more detailed numerical 
computations. This right-handed radio polarization should prevail 
for a bunch of electrons so long as their spatial distribution is 
not completely random. This theoretical result is consistent with 
the Ulysses Radio and Plasma Wave Experiment (URAP) observations 
(MacDowall 1993).

In year 2004, Ulysses will have a second rendezvous with Jupiter
in the northern heliosphere with a closest approach of $\sim 1000R_J$.
For global IRB oscillations and qualitatively similar polar
$\vec B$ configurations as well as level of irregularities, QP-40 
bursts of relativistic electrons and of accompanied radio emissions 
from the north pole are anticipated, especially during arrivals of 
high-speed solar winds at Jupiter. While Ulysses particle instruments 
cannot intercept QP-40 bursts of relativistic 
electrons (one still expects to observe a gradual increase of 
relativistic electron flux towards Jupiter), URAP will have a good 
opportunity to observe north polar QP-40 radio bursts outside the 
Jovian magnetosphere. As $\vec B$ points outward from the Jovian 
north pole, we predict that polarizations of north circumpolar 
QP-40 radio bursts should be predominantly left-handed.
%with occasional right-handed ones.

\subsection{Frequencies of QP-40 Radio Bursts}

Let us now estimate typical frequency components of a radio burst. 
As relativistic electrons leak out quasi-periodically during a 
certain phase in each period of IRB QP-40 oscillations, radio 
burst emissions are produced by the synchrotron process from 
relativistic electrons in nearly anti-parallel motions outward 
along south polar magnetic field lines. Such IRB
relativistic electrons initially drift across the narrow 
circumpolar zone about the magnetic axis and they gyrate 
transverse to the local surface $\vec B$, radiating intensely
in a perpendicular plane due to the relativistic beaming effect 
(i.e., strongest emissions within an angle $\lsim 1/\gamma$ 
about $\vec v$ direction).
The total power emitted by an electron is
$P(\gamma)=2(\gamma^2-1)e^4B^2\sin^2\alpha/(3m_e^2c^3)$. 

As electrons
stream outward from circumpolar magnetic footpoints with gyroradii
$r_c\sim\gamma m_ec^2/(eB)=1.7\times 10^3\gamma B^{-1}$ cm $\ll R_J$,
the magnetic mirror force rapidly converts transverse gyrations to 
parallel motions by conserving both particle energy 
${\cal E}\equiv\gamma m_ec^2$ and magnetic moment
${\cal E}_{\perp}/|\vec B|$ where ${\cal E}_{\perp}$ is the kinetic
energy of transverse gyration. The synchrotron emission cone ahead 
of a relativistic electron gyrating around $\vec B$ shrink in conal 
angle towards the forward direction of $\vec v$ with decreasing
characteristic frequencies (Ginzburg \& Syrovatskii 1965).
%Rybicki \& Lightman 1979). 

For a dipole magnetic field $|\vec B|\propto r^{-3}$ and a polar surface 
$|\vec B|$ strength of $\sim 10$G, the pitch angle $\alpha$ of electrons, 
independent of $\gamma$, becomes $\sim 6\times 10^{-3}$ at $\sim 30R_J$ 
or $\sim 4\times 10^{-3}$ at $\sim 40R_J$. The characteristic synchrotron 
emission frequency $\nu_c$ from a gyrating electron is given by
$
\nu_c=0.29\times 3\gamma^2eB\sin\alpha/(4\pi m_ec) 
$
(Rybicki \& Lightman 1979). For parameters of interest, 
we have $\nu_c\sim 3\gamma^2$ and $\sim 0.87\gamma^2$ at 
$\sim 30R_J$ and $\sim 40R_J$, respectively. For typical 
spectral profiles of QP-40 radio bursts, the dominant 
peak falls between $\sim 10-80$kHz (MacDowall et al. 1993). 
\footnote{A reduced intensity at about $40-50$ kHz may not 
be a common feature of the QP-40 bursts. The transition
from the URAP RAR Low to High band receivers occurs at
$\sim 50$ kHz.}
For a power-law number distribution
%(Bolton et al. 2002; Rybicki \& Lightman 1979) 
of IRB electrons in $\gamma$, this would imply 
relativistic electrons with a $\gamma$ range of as high as 
$\sim 160-300$. The recent Cassini synchrotron observation in space at 
2.2cm (13.8GHz) revealed electron energies of $\sim 50$MeV inside the 
IRB, with further hints of a high-energy tail with $\gamma\gsim 200$ 
at $r\gsim 2R_J$ (Bolton et al. 2002). 
%Furthermore, spectral profiles of QP-40 bursts (MacDowall et al.
%1993) show second peaks around 100kHz which would imply the 
%presence of ultra-relativistic electrons with $\gamma\sim 300$.
%
%Comments from Robert MacDowall:
%Concerning your question below, I do not believe that a
%reduction of intensity at about 40 - 50 kHz is a common
%feature of the QP-40 bursts, but I did not study this
%at the time of the 1993 paper. Note that the transition
%from the URAP RAR Low to High band receivers occurs at
%50 kHz.  Also, when the High band is in so-called SUMmation
%mode, the backgrounds are higher than in SEParate mode.
%The spectra in the figure that you discuss are NOT
%background subtracted.   In the next weeks, I
%will be doing a survey of the recent (2002) observations
%of QP bursts, as Ulysses once again moves towards
%Jupiter.  I will keep your question in mind and see
%what the trends are in the current data.  At the present
%time, I can't do a statistical study of the old data,
%but might be able to look at this later in the summer,
%if it is important for your work.
If $\sin\alpha$ is taken to be $\sim 1$ 
%in $\nu_c$ estimates 
as commonly assumed, then $\nu_c$ would be 
much higher than several hundred kilohertz.

\subsection{QP-40 Pulsations of Polar X-Ray Hot Spots}

With both magnetic poles being qualiatively equal, we focus
on pulsations of northern auroral X-ray hot spot of Jupiter 
with a $\sim 45$-minute period discovered lately (Gladstone 
et al. 2002) using the high-resolution camera (HRC) of the 
Chandra X-ray Observatory on 18 December 2000.
%in support of the Cassini fly-by of Jupiter. 
While physical processes leading to such polar X-ray hot spots 
inside the main far-ultraviolet (UV) polar auroral oval are 
currently unexplained, their QP-40 pulsations nontheless 
offer extremely valuable diagnostics for probing the inner 
magnetospheric environment. 

In the scenario of QP-40 IRB oscillations (Lou 2001), the
northern auroral X-ray hot spots should pulsate with a quasi-period 
of $\sim 40$ min as QP-40 magnetoinertial oscillations of the IRB
will affect, through fast MHD wave transmissions, the immediate 
environs that include circumpolar zones of open magnetic fields, and 
leave QP-40 oscillatory signatures there (Balogh et al. 1992). Almost 
certainly, $\sim 45$-min pulsations of southern auroral X-ray hot 
regions were not seen this time (Gladstone et al. 2002) primarily 
owing to an 
unfavorable viewing geometry from the Chandra HRC. We anticipate 
that, similar to QP-40 polar burst activities and IRB oscillations 
(MacDowall et al. 1993), pulsation magnitudes of such X-ray hot 
spots poleward of the far-UV auroral oval should be also enhanced 
upon arrivals of high-speed solar winds at Jupiter. One primary goal 
of the Chandra and HST campaigns supporting the Cassini fly-by is 
to search for connections between Jovian auroral transients and the 
interaction of the solar wind with Jupiter's magnetosphere; in fact, 
this is already in hand but not yet fully appreciated. 

It is promising to pursue a direct detection of Jupiter's 
QP-40 IRB brightness variations in the wavelength range 
of $\lambda\sim 6-90$ cm with magnitudes $\gsim 0.1$Jy by the
ground-based radio telescope facilities such as those at Effelsberg,
Very Large Array, Westerbork Synthesis Radio Telescope, Owen's Valley
Radio Observatory, and Australia Telescope Compact Array. The optimal 
condition for a detection can be derived in advance by combining the 
information of locations of the Earth and the Jupiter relative to 
the Sun and the knowledge of low-latitude solar X-ray coronal holes 
where fast solar winds emanate. As the Sun rotates with an 
equatorial period of $\sim 25-26$ days, fast solar wind streams 
recur in the interplanetary space (Lou 1994, 1996).
%and hence solar wind speed variations at Jupiter.
Meanwhile, it is crucial to establish the correlation of QP-40 
pulsations of polar X-ray hot spots with arrivals of high-speed 
solar winds using the Chandra HRC. As Jovian auroral ovals mark 
the boundary zones separating the closed $\vec B$ of IRB and the 
open polar $\vec B$, it is inevitable that far-UV auroral ovals 
may pulsate with a QP-40 period upon arrivals of high-speed solar 
winds; this prediction can be tested by Hubble Space 
Telescope imaging spectrograph (HST-STIS) observations.
\footnote{Grodent, et al. (2001) indicated in their AGU Spring Meeting 
abstract \#P52A-09 that the sampling of the HST-STIS at the time did 
not permit them to highlight a forty-minute oscillation in the 
corresponding ultraviolet light curve. }
%We then have to wait for other 
%occasions to test this prediction. }

\subsection{Coincidence with a High-Speed Solar Wind}

For the Chandra HRC 10-hour observation for X-ray QP-40 pulsations 
of Jupiter's polar hot spot on 18 December 2000 from 10-20 UT 
(Gladstone et al. 2002), we show that this observation run 
happened to coincide with an arrival of high-speed wind at 
Jupiter. We obtained pertinent information from the website 
ssd.jpl.nasa.gov/
under Mean Orbital Elements for both the Earth and Jupiter,
and from the websites
www.sec.noaa.gov/ace/ACErtsw$\_$home.html and
www2.crl.go.jp/uk/uk223/service/arc/
for the archival data of real-time solar wind properties 
measured by the ACE spacecraft.
%Advanced Composition Explorer (ACE).
%The specifics are given below. 
On 12:00 noon of 1 January 2000,
the Earth longitude L$_{E}=100.46435$ deg and the Jupiter
longitude L$_{J}=34.40438$ deg, respectively.
The mean angular rate of the Earth is $129597740.63''$/100yr=
$3548.1928''$/day=0.9856091 deg/day and the mean angular
rate of the Jupiter is $10925078.35''$/100yr=$299.11234''$/day
=0.08308676 deg/day. On 12:00 noon of 18 December 2000,
L$_{E}=87.398753$ deg and L$_{J}=63.65092$ deg. A high-speed 
wind of $\sim 700\hbox{ km s}^{-1}$ present at Jupiter on 
12:00 noon of 18 December 2000 should imply the leading edge of 
a low-latitude coronal hole at longitude L$_{H}=62.65$ deg on 
2:24 AM of 6 December 2000. As the equatorial angular rotation
rate of the Sun is $\sim 27$ days, 
%(13.33333 deg/day), 
a high-speed wind of $\sim 700\hbox{ km s}^{-1}$ is 
estimated to reach the Earth after 3:00 PM of 9 December 2000. 
According to the ACE data for the real-time solar wind speed 
$U$ in unit of $\hbox{km s}^{-1}$, we have
$390\lsim U\lsim 450$,
$550\lsim U\lsim 650$,
$650\lsim U\lsim 700$,
$700\gsim U\gsim 600$,
$600\gsim U\gsim 540$,
$550\gsim U\gsim 430$,
$440\gsim U\gsim 400$,
$U\sim 390$,
$380\gsim U\gsim 320$,
and $U\sim 330$ on $7-16$ December 2000, respectively. So a 
high-speed solar wind of $\sim 700\hbox{ km s}^{-1}$ did indeed 
arrive the Earth on 9 and 10 December 2000 by the ACE data.

As the polar X-ray hot spot is near the IRB, this observed result 
is consistent with the scenario that QP-40 IRB oscillations are 
excited more prominently at the arrival of high-speed solar wind. 
We need more Chandra HRC observations and correlation studies with 
the ACE solar wind speed data to firmly establish this important 
revelation. As the Jovian auroral ovals separate closed magnetic 
fields of the IRB from open magnetic fields of the pole, it is 
natural to expect that the far UV auroral ovals around the Jovian 
magnetic poles should also oscillate with a QP-40 period by the 
HST-STIS observations during that period of time.

\section{Summary and Conclusions}

Based on empirical clues, intuitive considerations, and 
theoretical analysis, it is physically plausible and 
appealing that polar QP-40 bursts of relativistic 
electrons and radio emissions involve global QP-40 IRB 
oscillations of Jupiter. With this scenario in mind, we 
summarize below key results and testable predictions.

\noindent
(1) QP-40 burst electrons, protons, and alpha particles with
relativistic energies most likely originated from the Jovian 
IRB (Lou 2001) where relativistic electrons with $\gamma$ as 
high as $\sim 100-200$ are known to exist (Bolton et al. 2002). 
They escape from the Jovian circumpolar region and are modulated 
by global QP-40 IRB oscillations. Some of escaping relativistic 
electrons may attain large $\gamma$ as indicated.

\noindent
(2) As estimated here, the predicted QP-40 brightness 
variations of the IRB should be observable by existing ground-based 
radio telescopes. It is extremely important to verify the expected 
correlation of such QP-40 brightness variations with arrivals of 
high-speed solar winds. Under favorable situations, higher harmonics 
of QP oscillations with shorter periods (Lou 2001) might also be 
detectable.

\noindent
(3) The QP-40 IRB oscillations are most likely excited and 
sustained by the combined effects of solar wind speed 
variations, of short-term intermittent wind speed 
variations during either fast or slow wind phase, and of 
angular momentum conservation of Jovian magnetospheric plasma.

\noindent
(4) Assuming a similar level of inhomogeneities for both north 
and south polar magnetic fields, we predict QP-40 bursts of 
relativistic electrons of the IRB from Jupiter's north polar 
region. Moreover, such QP-40 north polar activities are expected 
to correlate well with arrivals of high-speed solar winds at 
Jupiter. In coordination with spacecraft observations of solar 
wind properties, another spacecraft needs to be launched to 
enter Jovian magnetosphere and to probe the north polar region 
in order to test this prediction.

\noindent
(5) At $30-40R_J$ away from the Jupiter, synchrotron emissions 
with small pitch angles $\alpha$ are stronger than curvature 
emissions in QP-40 radio bursts associated with relativistic 
electrons streaming along south polar magnetic field lines of 
Jupiter. The observed predominance of right-handed polarization 
of radio burst emissions is consistent with the gyration sense 
of outstreaming electrons in the south polar magnetic field 
pointing towards Jupiter. North polar QP-40 radio bursts 
associated with north polar QP-40 bursts of relativistic 
electrons are expected and should be detectable by Ulysses, 
now approaching the Jupiter 
in the northern heliosphere. Because Jupiter's north polar 
magnetic field points outward, we thus predict the 
polarization of north polar QP-40 radio bursts to be 
predominantly left-handed. These predictions can be tested 
by Ulysses observations in the near future (year 2003-2004).

\noindent
(6) Based on one case of coincidence of QP-40 pulsations of north 
polar X-ray hot spots with an arrival of high-speed solar wind 
at Jupiter and our global QP-40 IRB oscillation scenario, we would
like to emphasize the importance of empirically establishing 
this correlation through more coordinated spacecraft observations. 

\noindent
(7) Latitudewise, the Jovian auroral ovals lie between the IRB 
and the polar X-ray hot spots. Through magnetospheric wave
transmissions of IRB oscillations to neighboring polar magnetic 
fields, we naturally expect QP-40 pulsations of Jovian aurora 
ovals in correlation with arrivals of high-speed solar winds
at Jupiter. For example, this prediction can be tested by 
well-prepared HST-STIS observations of FUV auroral ovals with 
appropriate sampling rate.

By this Letter, we hope to stimulate more observational and
theoretical studies on QP-40 polar activities of Jupiter 
and to identify the physical cause of QP-40 phenomena.

\section*{Acknowledgments}

This research has been supported in part 
%by grants from the US NSF (ATM-9320357, AST-9731623) 
%to the University of Chicago, 
by the ASCI Center for Astrophysical Thermonuclear Flashes 
at the University of Chicago under Department of Energy 
contract B341495,
%by the Visiting Scientist Programs at the Institute
%of Astronomy and Astrophysics, Academia Sinica
%(NSC-88-2816-M-001-0010-6 and NSC89-2816-M001-0006-6) and
%at the National Taiwan University (NSC89-2112-M002-037),
by the Special Funds for Major State Basic Science
Research Projects of China, by the Collaborative
Research Fund from the NSF
%National Natural Science Foundation
of China (NSFC) for Young Outstanding Overseas Chinese
Scholars (NSFC 10028306) at the National Astronomical
Observatory, Chinese Academy of Sciences, and by the
Yangtze Endowment from the Ministry of Education through
the Tsinghua University.
Affliated institutions share this contribution.

\begin{thebibliography}{2002}

\bibitem[]{} Balogh A., et al., 1992, Science, 257, 1515
%Magnetic field observations during the Ulysses flyby of Jupiter.
%{\it Science} {\bf 257}, 1515 (1992);
%-1518 (1992).
%1992, Science, 257, 1515
%-1518; Magnetic field observations during the Ulysses flyby of Jupiter.
%M. K. Gougherty, R. J. Forsyth, D. J. Southwood,
%E. J. Smith, B. T. Tsurutani, N. Murphy, M. E. Burton

\bibitem[]{} Bame S. J., et al., 1992, Science, 257, 1539
%1992, Science, 257, 1539-1543; Jupiter's magnetosphere: Plasma
%description from the Ulysses flyby.
%Samuel; Bruce L. Barraclough, William C. Feldman, Galen R. Gisler,
%John T. Gosling, David J. McComas, John L. Philips, Michelle F.
%Thomsen, Bruce E. Goldstein, Marcia Neugebauer

\bibitem[]{} Bolton  S. J., et al., 1989, J. Geophys. Res., 94, 121 
%--128; Correlation studies between solar wind parameters 
%and the decimeric radio emission from Jupiter.
%S. Gulkis, M. J. Klein, I. de Pater, T. J. Thompson

\bibitem[]{} Bolton  S. J., et al., 2002, Nature, 415, 987
%Ultra-relativistic electrons in Jupiter's radiation belts.
%{\it Nature} {\bf 415}, 987 (2002).
%-991 (2002).
%total 21 authors. up to 50MeV electrons. 2.2cm
%(13.8GHz) wavelength of synchrotron radiation.

\bibitem[]{} Coroniti F. V., 1975, Space Sci. Rev., 17, 837
%D\'enouement of Jovian radiation belt theory.
%{\it Space Sci. Rev.} {\bf 17}, 837 (1975);
%-856 (1975).
%\Journal{1975}{\SSR}{17}{837}.
%--856; D\'enouement of Jovian radiation belt theory.
%immediately followed by a paper by Kennel C. and Coroniti F. V. p. 857

\bibitem[]{} de Pater I., 1990, ARA\&A, 28, 347
%Radio images of the planets.
%{\it Annu. Rev. Astron. Astrophys.} {\bf 28}, 347 (1990);
%-400 (1990).
%1990, ARA\&A, 28, 347-400; Imke;
%Radio images of the planets; synchrotron radiation
%belt image in Figure 3 (20cm); very impressive.

\bibitem[]{} Desch M. D., 1994, ApJS, 90, 541
%Jupiter radio bursts and particle acceleration.
%{\it Astrophys. J. Suppl.} {\bf 90}, 541 (1994).
%-546 (1994).
%1994, ApJS, 90, 541
%-546; Jupiter radio bursts and particle acceleration.
%Proc. IAU Symposium #142, in Particle Acceleration
%quoted by MacDowall et al.; Beautiful color plates 1 and 2.
%high-energy particle beam have been observed in close
%association with the QP bursts; an intermediate agent is at
%work, perhaps related to a substorm-like process at Jupiter.
%"Although the phenomena are clearly related in some way
%the large temporal offset (8 minutes) implies that since
%both the waves and particles travel essentially at light
%speed c, there must be an intermediate step or steps
%between wave generation and particle acceleration. The
%particles themselves do not give rise to the radio emission."
%This statement may not be correct!!
%At the time of the observed correlation, Jupiter's magnetosphere
%was undergoing a large-scale compression due to a major enhancement
%in the solar wind density.

\bibitem[]{} Ginzburg V. L., Syrovatskii S. I., 1965, ARA\&A, 3, 297
%Cosmic Magnetobremsstrahlung (Synchrotron Radiation).
%{\it Annu. Rev. Astron. Astrophys.} {\bf 3}, 297 (1965).
%-350 (1965).

\bibitem[]{} Gladstone G. R., et al., 2002, Nature, 415, 1000
%A pulsating auroral X-ray hot spot on Jupiter.
%{\it Nature} {\bf 415}, 1000 (2002).
%-1003 (2002).
%total 15 authors.
%J. H. Waite, Jr., D. Grodent, W. S. Lewis,
%F. J. Crary, R. F. Elsner, M. C. Weisskopf,
%T. Majeed, J.-M. Jahn, A. Bhardwaj,
%J. T. Clarke, D. T. Young, M. K. Dougherty,
%S. A. Espinosa, T. E. Craven
%45-min period; north polar auroral zone.

\bibitem[]{} Gurnett D. A., et al., 2002, Nature, 415, 985 
%--987; 
%W.S. Kurth, G. B. Hospodarsky, A. M. Persoon,
%P. Zarka, A. Lecacheux, S. J. Bolton, M. D. Desch,
%W. M. Farrell, M.L. Kaiser, H.-P. Ladreiter,
%H. O. Rucker, P. Galopeau, P. Louarn,
%D. T. Young, W.R. Pryor, M.K. Dougherty
%Control of Jupiter's radio emission
%and aurorae by the solar wind.

\bibitem[]{} Lou Y. Q., 1994, J. Geophys. Res., 99, 14747 
%``Alfv\'enic Disturbances in the Equatorial Solar
%Wind with a Spiral Magnetic Field", Lou, Y.Q. {\it Journal of
%Geophysical Research}, {\bf 99}, 14,747-14,760, 1994.

\bibitem[]{} Lou Y. Q., 1996, Geophys. Res. Lett., 23, 609
%{\bf 23}, 609 (1996).
%--612; Corotating Shock Accelerated Particles Guided by
%Wavy Spiral Magnetic Fields in the Solar Wind at High
%Heliospheric Latitudes

\bibitem[]{} Lou Y. Q., 2000, ApJ, 540, 1102
%``Rossby-Type Wave Induced Periodicities in Flare Activities 
%and Sunspot Areas or Groups during Solar Maxima", 
%--1108; oddjob directory: rossby/rsbym.gly

\bibitem[]{} Lou Y. Q., 2001, ApJ, 548, 460
%Magnetoinertial oscillations of Jupiter's inner radiation belt.
%{\it Astrophys. J.} {\bf 548}, 460 (2001).
%-465 (2001).

\bibitem[]{} MacDowall  R. J., et al., 1993,
Planet. Space Sci., 41, 1059
%Quasiperiodic Jovian radio bursts: observations
%from the Ulysses Radio and Plasma Wave Experiment.
%{\it Planet. Space Sci.} {\bf 41}, 1059 (1993).
%-1072 (1993).
%1993, Planet. Space Sci., 41, 1059-1072;
%Quasiperiodic Jovian radio bursts: observations
%from the Ulysses Radio and Plasma Wave Experiment
%M. L. Kaiser, M. D. Desch, W. M. Farrell, R. A. Hess,
%R. G. Stone
%beautiful figures 2 and 6 (color).
%a nice histogram in Figure 3.
%quasi-periodic electron acceleration?
%dusk terminator: asymptotically approaching \sim 40 S
%jovigraphic latitude.
%The onset of enhanced 40min burts activity is well
%correlated with the arrival of high-speed solar wind
%streams at Jupiter;
%QP-40 radio bursts -- direction from the south pole.
%15min period during inbound of Ulysses.
%The source locations of QP-15 radio bursts remain uncertain.
%Voyager 1 $\gsmi 0.4$Mev protons with a
%periodicity of $\sim 40$min (pre-dawn magnetosphere outbound pass);
%thousands of QP-40 events during two years following
%the encounter of Jupiter.
%this problem is central to a more complete understanding
%of Jupiter's environment.
%12-15min QP-15 and 30-40min QP40.
%QP-15 bursts were predominantly observed by Ulysses
%during its in-ecliptic approach to Jupiter.
%almost certain the same class of radio burst events observed
%by Voyager Plasma Wave Receiver (PWR) (Kurth et al. 1989)
%cited by MacDowall et al.
%QP-40 almost exclusively outbound from Jupiter -- 40^0S
%of jovigraphic latitude.
%QP-40 bursts and 50kev electrons observed by the Ulysses
%HI-SCALE instrument (Lanzerotti, private communications).
%mentioned electron cyclotron maser instability (Wu and Lee 1979).
%The Ulysses flyby of Jupiter ....
%Unified Radio and Plasma Wave Experiment (URAP).
%The large peak at 2 min occur because the algorithm is
%permitted to detect events in successive frequency
%sweeps and the duration of QP-40 variation is
%significantly longer than 128 seconds.
%delays between successive bursts in a group sometimes
%agree to within a few percent. Subsequent groups of
%bursts may occur with different periods and phases.
%QP-15 both at longitude 0-140 deg are the abrupt onset;
%are similar to the behavior of the "escape" component
%of Jovian nonthermal continuum radiation.
%QP-40 weakly couples with sub-spacecraft longitude.
%They are twice as likely to be observed at $\sim 20$ deg.
%as at $\sim 200$ deg., i.e. they are more likely to be
%observed when the south magnetic pole tips toward Ulysses.
%radio source location at $\sim 5$ R_J
%may be a simple beaming pattern associated with the QP-40 events.
%Certain exciter originate in a region which corotates with
%the planet
%QP-15 \sim 10^7 W per (large) burst; occur in magnetosheath
%(believed by some, e.g. Desch 1994);
%QP-40 \sim 10^8 W per (large) burst.
%explain "Jovian type III bursts" may be inappropriate.
%While Ulysses was inside the Jovian magnetosphere, other
%wave and particle observations indicate similar periodicities.
%URAP capability for determining the direction of arrival and
%polarization of the radio waves.
%also correlate with Kev electrons.
%QP-15 :   26 (or 13) day variability;
%As of Nov.1993---4.5a.u. from Jupiter (out of the ecliptic plane).

\bibitem[]{} McKibben R. B., Simpson J. A.,
Zhang M., 1993, Planet. Space Sci., 41, 1041
%Impulsive bursts of relativistic electrons discovered during
%Ulysses' traversal of Jupiter's dusk-side magnetosphere.
%{\it Planet. Space Sci.} {\bf 41}, 1041 (1993);
%-1058 (1993).
%1993, Planet. Space Sci., 41, 1041
%-1058; Impulsive bursts of relativistic electrons discovered
%during Ulysses' traversal of Jupiter's dusk-side magnetosphere.
%Planetary and Space Science (QC879.A1P7)
%somewhat different from the preprint I have in possession.
%solution of the problem leads to important insights into the
%dynamics of the Jovian magnetopshere.
%electron energies \gsim 8 Mev;
%sometimes radio precedes electron bursts
%HI-SCALE 50 Kev electrons close to kilometric radiation
%cited Lanzerotti for private communications.
%3\times 10^{10}/2\times 10^{5}\sim 1.5 km wavelength.
%Whether QP-40 represent a characteristic period for
%some global oscillations in the magnetosphere that
%interacts with conditions local to the dusk side
%magnetosphere to produce particle acceleration.
%(seems to prefer a global resonance)
%However, periodicity is not exact.
%A significant and surprising finding is that there are
%also periods when no large-scale electron bursts
%actually is present that show evidence for a strong
%\sim 40 min period in the bidirectional anisotropy amplitudes.
%For \gamma=20; B=15\times 10^{-5} G; r_c=2000 km.
%A unidirectional field aligned anisotropy is not consistent
%with a stably trapped population of particles, which would
%display a bidirectional anisotropy which could be either
%field aligned or normal to the field.
%spiky electron bursts;
%enhanced fluxes persist several tens of hours;
%QP-40 bursts were more likely to be observed when the
%South magnetic pole was tipped toward the spacecraft.
%not every electon burst show the strong unidirectional anisotropy.
%large burst \gsim 10^{27} electrons.

\bibitem[]{} Miyoshi Y., et al., 1999, Geophys. Res. Lett, 26, 9 
%Misawa, H., \& Morioka, A. 1999, GRL, 26, 9-12
%Observations of short-term variations of Jupiter's
%synchrotron radiation. 12 yr revolution cycle; a few days
%UV/EUV irradiation. 21cm 20% increase.

\bibitem[]{} Nishida A., 1976, J. Geophys. Res., 81, 1771
%Outward diffusion of energetic particles from the Jovian radiation belt.
%{\it J. Geophys. Res.} {\bf 81}, 1771 (1976).
%-1773 (1976).
%\Journal{1976}{\JGR}{81}{1771}.
%-1773;

\bibitem[]{} Nishida A., Watanabe Y., 1981, 
J. Geophys. Res., 86, 9945
%Joule Heating of the Jovian Ionosphere by Corotation
%Enforcement Currents.
%{\it J. Geophys. Res.} {\bf 86}, 9945 (1981).
%9945-9952 (1981).
%\Journal{1981}{\JGR}{86}{9945}.
%-9952; Joule Heating of the Jovian Ionosphere
%by Corotation Enforcement Currents

\bibitem[]{} Northrop T. G., 1963, The Adiabatic Motion 
of Charged Particles. Interscience Publishers, New York 

\bibitem[]{} Roberts J. A., Berge G. L.,
Bignell R. C., 1984, ApJ, 282, 345
%High-resolution maps of the 1.5 GHz emission from
%Jupiter's disk and radiation belt.
%{\it Astrophys. J.} {\bf 282}, 345 (1984);
%-358 (1984).
%1984, ApJ, 282, 345--358; High-resolution maps of the 1.5 GHz
%emission from Jupiter's disk and radiation belt. many nice figures.

\bibitem[]{} Rogers J. H., 1995, The Giant Planet Jupiter.
Cambridge University Press, Cambridge, England 
%John;
%insubstantial realm of magnetic fields and electrical particles;
%in Jupiter's radiation belt, the trapped particles are some
%tenfold more energetic than in the equatorial belt of Earth;
%several orders of magnitude more abundant;
%Jupiter more rotational constrained than Earth.
%indeed,, in some ways it resembles a low-energy model of a pulsar.
%magnetic field rotates with a period of 9h 55m 29.71s (\pm 0.02s);
%system III longitude;
%the polarity is opposite to that of Earth.
%magnetic field strength 10-14 G at the poles.
%decimetric radiation (discovered in 1958),
%0.1-3m, 3-0.1 GHz, almost steady, total power 2\times 10^9 W,
%synchrotron from radiation belts.
%Table 18.2;

\bibitem[]{} Rybicki G. B., Lightman A. P., 1979,
Radiative Processes in Astrophysics. John Wiley \& Sons, New York

\bibitem[]{} Sault R. J., Oosterloo T., Dulk G. A., 
Leblanc Y., 1997, A\&A, 324, 1190
%{\it Astron. Astrophys.} {\bf 324}, 1190 (1997).
%1997, A\&A, 324, 1190
%-1196; The First Three-Dimensional Reconstruction of
%a Celestial Object at Radio Wavelengths: Jupiter's
%Radiation Belts.

\bibitem[]{} Schardt A. W., McDonald F. B.,
Trainor J. H., 1981, J. Geophys. Res., 86, 8413 
%Energetic particles in the predawn magnetotail of Jupiter.
%{\it J. Geophys. Res.} {\bf 86}, 8413 (1981).
%-8428 (1981).
%--8428; Energetic particles in the predawn magnetotail of Jupiter.
%Voyager 1 and 2; 40 min. period not clearly stated or not obvious.
%somehow other people cited this work for that. The prevalence of
%these phenomena was not apparent from the Voyager observations.

\bibitem[]{} Schultz M., Lanzerotti L. J., 1974, Particle 
Diffusion in the Radiationa Belts. Springer Verlag, New York

\bibitem[]{} Simpson J. A., et al., 1975, Science, 188, 455
%-459; Jupiter revisited: First results from the University
%of Chicago Charged Particle Experiment on Pioneer 11
% Hamilton D C, Lentz G A, McKibben R B, Perkins M. Pyle K R.
% Tuzzolino J, O'Gallagher J J.

\bibitem[]{} Simpson J. A.,  et al., 1992, Science, 257, 1543
%Energetic charged-particle phenomena in the Jovian magnetosphere:
%First results from Ulysses COSPIN collaboration.
%{\it Science} {\bf 257}, 1543 (1992);
%-1550 (1992).
%1992, Science, 257, 1543-1550;
%Energetic charged-particle phenomena in the Jovian magnetosphere:
%First results from Ulysses COSPIN collaboration
%J. D. Anglin, A. Balogh, I. R. Burrows, S.W.H. Cowley,
%P. Ferrando, B. Heber, R. J. Hynds, H. Kunow, R. G. Marsden,
%R. B. McKibben, R. M\"uller-Melin, D. E. Page, A. Raviart,
%T. R. Sanderson, K. Staines, K.-P. Wenzel, Margret D. Wilson,
%M. Zhang.
%40 min. period relativistic electron bursts and radio bursts.

\bibitem[]{} Stone R. G., et al., 1992, Science, 257, 1524
%Stone, R. G. {\it et al.} Ulysses radio
%and plasma wave observations in the Jupiter environment.
%{\it Science} {\bf 257}, 1524-1531 (1992).
%B. M. Pedersen, C. C. Harvey, P. Canu, N. Cornilleau-Wehrlin,
%M. D. Desch, C. de Villedary, J. Fainberg, W. M. Farrell,
%K. Goetz, R. A. Hess, S. Hoang, M. L. Kaiser, P. J. Kellogg,
%A. Lecacheux, N. Lin, R. J. MacDowall, R. Manning,
%C. A. Meetre, N. Meyer-Vernet, M. Moncuquet,
%V. Osherovich, M. J. Reiner, A. Tekle, J. Thiessen, P. Zarka


\bibitem[]{} Walt M., 1994, Introduction to Geomagnetically
Trapped Radiation. Cambridge University Press, Cambridge

\bibitem[]{} Zhang M., et al., 1995,
J. Geophys. Res., 100, 19497
%Impulsive bursts of energetic particles in the high-latitude
%duskside magnetosphere of Jupiter.
%{\it J. Geophys. Res.} {\bf 100}, 19,497 (1995);
%-19,512 (1995).
%McKibben R. B., Simpson J. A., Cowley S. W. H., Staines K.,
%Anglin J. D., Marsden R. G., Sanderson T. R., Wenzel K.-P.

\bibitem[]{} Zhang M., Simpson J. A., McKibben R. B.,
1993, Planet. Space Sci., 41, 1029
%Relativistic electron flux anisotropies in the dusk-side Jovian
%magnetosphere: A test for source location and escape mechanism.
%{\it Planet. Space Sci.} {\bf 41}, 1029 (1993).
%-1040 (1993).
%Relativistic electron flux anisotropies in the dusk-side Jovian
%magnetosphere: A test for source location and escape mechanism.
%Planetary and Space Science
%$\gsim 3$Mev electron flux; 40 -- 45 days of 1992;
%electron flux $\gsim 10^{26}\hbox{ s}^{-1}$;
%a fraction of interplanetary Jovian electrons may escape
%the magnetosphere in this way.
%Jupiter is a strong source of relativistic electrons
%propagating in the interplanetary space.
%Nishida (1976) circulation model tested. generally in favor;
%inward diffusion of solar wind electron for energy gains;
%outward diffusion from IRB do not degrade energy;
%pitch angle of e \sim 90 deg for low L.
%polar leakage is another means of getting relativistic
%electrons out (what is the fraction?); someone mentioned
%relativistic electron jets.

\end{thebibliography}

%% Generally speaking, only the figure captions, and not the figures
%% themselves, are included in electronic manuscript submissions.
%% Use \figcaption to format your figure captions. They should begin on a
%% new page.

\clearpage

%% No more than seven \figcaption commands are allowed per page,
%% so if you have more than seven captions, insert a \clearpage
%% after every seventh one.

%% There must be a \figcaption command for each legend. Key the text of the
%% legend and the optional \label in curly braces. If you wish, you may
%% include the name of the corresponding figure file in square brackets.
%% The label is for identification purposes only. It will not insert the
%% figures themselves into the document.
%% If you want to include your art in the paper, use \plotone.
%% Refer to the on-line documentation for details.

%% Tables should be submitted one per page, so put a \clearpage before
%% each one.

%% Two options are available to the author for producing tables:  the
%% deluxetable environment provided by the AASTeX package or the LaTeX
%% table environment.  Use of deluxetable is preferred.
%%

%% Three table samples follow, two marked up in the deluxetable environment,
%% one marked up as a LaTeX table.


%% In this first example, note that the \footnotesize command has been
%% used to shrink the table so it will fit on one page. Note also that
%% the \label command needs to be placed inside the \tablecaption.

\clearpage

%% Tables may also be prepared as separate files. See the accompanying
%% sample file table.tex for an example of an external table file.
%% To include an external file in your main document, use the \input
%% command. Uncomment the line below to include table.tex in this
%% sample file.

% \input{table}

%% The following command ends your manuscript. LaTeX will ignore any text
%% that appears after it.

\label{lastpage} 

\end{document}

***************************************************************
\vskip -4pt
\noindent
\hbox{ }3. \hbox{ } Han, J. L., {\it et al.} Magnetic fields in
the spiral galaxy NGC 2997. {\it Astron. Astrophys.} {\bf 348},
405-417 (1999).
%central region three spiral Stephane Leon (private communicatios);
%Debra Elmegreen near-infrared image of circumnuclear ring.
%in J and K bands.

\vskip -4pt
\noindent
\hbox{ }4. \hbox{ } Lou, Y. Q., Han, J. L. \& Fan, Z. H.
Fast magnetohydrodynamic density waves in spiral galaxies.
{\it Mon. Not. R. Astron. Soc.} {\bf 308}, L1-L5 (1999).

\vskip -4pt
\noindent
\hbox{ }27. \hbox{ } Maoz, D. {\it et al.} Hubble Space
Telescope ultraviolet images of five circumnuclear
star-forming rings. {\it Astron. J.} {\bf 111},
2248-2264 (1996).
%Dan Maoz, Aaron J. Barth, Amiel Sternberg, Alexei V.
%Filippenko, Luis C. Ho, F. Duccio Macchetto,
%Hans-Walter Rix, Donald P. Schneider. Figure 2
%contains HST images of NGC 2997 (2300 A and 6060 A)
%of the central spiral. Table 5 lists compact sources
%of NGC 2997.

\vskip -4pt
\noindent
\hbox{ }26. \hbox{ } Elmegreen, D. M., Chromey, F. R.,
Sawyer, J. E. \& Reinfeld, E. L. Near-infrared
observations of hot spots in the circumnuclear rings
of NGC 2997 and NGC 6951. {\it Astron. J.} {\bf 118},
777-784 (1999).
%1999, AJ, 118, 777-784
%Figure 3 used Maoz et al. HST image of NGC 2997.
%Unsharp-masked technique has been applied to NIR data.
%in the J and K bands.

\vskip -4pt
\noindent
\hbox{ }9. \hbox{ } Bertin, G., Lin, C. C., Lowe, S. A.
\& Thurstan, R. P. Modal apporach to the morphology of
spiral galaxies. II. Dynamical mechanisms.
{\it Astrophys. J.} {\bf 338}, 104-120 (1989).

\vskip -4pt
\noindent
\hbox{ }6. \hbox{ } Elmegreen, B. G., {\it et al.}
%Elmegreen D. M.,  Brinks, E., Yuan, C., Kaufman M.,
%Klari\'c, M., Mongtenegro, L., Struck C.,  Thomasson M.
Dust spirals and acoustic noise in the nucleus of the
galaxy NGC 2207.
{\it Astrophys. J.} {\bf 503}, L119-L122 (1998).

\vskip -4pt
\noindent
\hbox{ }14. \hbox{ } Binney, J. \& Tremaine, S.
{\it Galactic Dynamics} (Princeton University
Press, Princeton, 1987).

\vskip -4pt
\noindent
\hbox{ }15. \hbox{ } Bertin, G. \& Lin, C. C.
{\it Spiral Structure in Galaxies: A Density
Wave Theory} (MIT Press, Cambridge, MA, 1996).

\vskip -4pt
\noindent
\hbox{ }16. \hbox{ } Krolik, J. H. {\it Active
Galactic Nuclei} (Princeton University Press,
Princeton, 1999).
%From the Central Black Hole to the Galactic
%Environment

\vskip -4pt
\noindent
\hbox{ }29. \hbox{ } Osmer, P. S., Smith M. G.,
Weedman D. W., ApJ, 192, 279-291, 1974
%The neclei of peculiar emission-line galaxies.
%including NGC 1097 and 2997.

\vskip -4pt
\noindent
\hbox{ }30. \hbox{ } Young, J. S., Sanders, D. B.,
ApJ, 302, 680-692, 1986
%Distributions of $^{13}$CO emission in the disks
%of late-type spiral galaxies.
%Five College Radio Astronomy Observatory (FCRAO)
%14 m millimeter telescope; resolution 45'' HPBW;
%objects include: IC 342, NGC 6946, M83 (NGC 5236),
%NGC 1068,  NGC 4321, and M51 (NGC 5194)


The master dispersion relation can be arranged into
the following dimensionless form
$$\eqalign{
[1+K^2(Q_M^2&-Q^2)/4-\nu^2]^2\nu^2 \cong
\lbrace [-K^2\nu^2+m^2\epsilon^2 K^2(Q_M^2-Q^2)/4]\cr &
\times [1+K^2(Q_M^2-Q^2)/4-\nu^2]-J^2\nu^2\rbrace
(Q^2/4-1/K)\cr}\eqno(1)
$$
where dimensionless quantities are defined by
$\nu^2\defeq (\omega-m\Omega)^2/\kappa^2\ $,
$$
K\defeq {2\pi G\mu_{\circ}\over\kappa^2}
\bigg(k^2+{m^2\over r^2}\bigg)^{1/2}\ , \eqno(2)
$$
$$
Q_M^2\defeq {(C_S^2+C_A^2)\kappa^2\over (\pi G\mu_{\circ})^2}\ ,\eqno(3)
$$
$$
Q^2\defeq {C_S^2\kappa^2\over (\pi G\mu_{\circ})^2}\ ,\eqno(4)
$$
$$
\epsilon^2\equiv \bigg({2\pi G\mu_{0}\over r\kappa^2}\bigg)^2\ ,\eqno(5)
$$
$$
J^2\defeq m^2\bigg({\pi G\mu_{\circ}\over r\kappa^2}\bigg)^2
\bigg({4\Omega\over\kappa}\bigg)^2
\bigg|{d\ln\Omega\over d\ln r}\bigg|\ .\eqno(6)
$$
%MHD overstability (as an excitation)$^{5, 6}$ ---
%magnetic field/gas density correlations
%
%angular momentum transport or loss
%
%central accretion
%
%circumnuclear ring of star formation (actually tightly wound
%spirals)
%
%state-of-art synchrotron radio observations (higher
%spatial resolution is needed)
%
%past examples spiral galaxies, M83 (Beck 1998 private communications),
%NGC 6946, IC 342 etc. specific references needed.
%
%composite system of stellar and magnetic gas disks
%
%Estimates$^{25}$ of molecular hydrogen H$_2$ in the central
%region of NGC 1097 are $\sim 6\times 10^{22}\hbox{ cm}^{-2}$
%which corresponds to a surface mass density of
%$\sim 0.2\hbox{ g cm}^{-2}$.
%
%In the MHD density wave scenario, dust lanes are not necessarily
%the channels to {\it directly} feed the circumnuclear ring or
%central accretionactivities.
%
%Spiral magnetic field structure is associated fast MHD density waves.
%
%The magnetic features of NGC 1097 are generic (other barred
%galaxies$^{1}$ NGC 1365, NGC 2442 and NGC 7552). NGC 5383,
%NGC 2997.
 

astro-ph0307276.extracted_bib
\begin{thebibliography}{2002}

\bibitem[]{} Balogh A., et al., 1992, Science, 257, 1515
%Magnetic field observations during the Ulysses flyby of Jupiter.
%{\it Science} {\bf 257}, 1515 (1992);
%-1518 (1992).
%1992, Science, 257, 1515
%-1518; Magnetic field observations during the Ulysses flyby of Jupiter.
%M. K. Gougherty, R. J. Forsyth, D. J. Southwood,
%E. J. Smith, B. T. Tsurutani, N. Murphy, M. E. Burton

\bibitem[]{} Bame S. J., et al., 1992, Science, 257, 1539
%1992, Science, 257, 1539-1543; Jupiter's magnetosphere: Plasma
%description from the Ulysses flyby.
%Samuel; Bruce L. Barraclough, William C. Feldman, Galen R. Gisler,
%John T. Gosling, David J. McComas, John L. Philips, Michelle F.
%Thomsen, Bruce E. Goldstein, Marcia Neugebauer

\bibitem[]{} Bolton  S. J., et al., 1989, J. Geophys. Res., 94, 121 
%--128; Correlation studies between solar wind parameters 
%and the decimeric radio emission from Jupiter.
%S. Gulkis, M. J. Klein, I. de Pater, T. J. Thompson

\bibitem[]{} Bolton  S. J., et al., 2002, Nature, 415, 987
%Ultra-relativistic electrons in Jupiter's radiation belts.
%{\it Nature} {\bf 415}, 987 (2002).
%-991 (2002).
%total 21 authors. up to 50MeV electrons. 2.2cm
%(13.8GHz) wavelength of synchrotron radiation.

\bibitem[]{} Coroniti F. V., 1975, Space Sci. Rev., 17, 837
%D\'enouement of Jovian radiation belt theory.
%{\it Space Sci. Rev.} {\bf 17}, 837 (1975);
%-856 (1975).
%\Journal{1975}{\SSR}{17}{837}.
%--856; D\'enouement of Jovian radiation belt theory.
%immediately followed by a paper by Kennel C. and Coroniti F. V. p. 857

\bibitem[]{} de Pater I., 1990, ARA\&A, 28, 347
%Radio images of the planets.
%{\it Annu. Rev. Astron. Astrophys.} {\bf 28}, 347 (1990);
%-400 (1990).
%1990, ARA\&A, 28, 347-400; Imke;
%Radio images of the planets; synchrotron radiation
%belt image in Figure 3 (20cm); very impressive.

\bibitem[]{} Desch M. D., 1994, ApJS, 90, 541
%Jupiter radio bursts and particle acceleration.
%{\it Astrophys. J. Suppl.} {\bf 90}, 541 (1994).
%-546 (1994).
%1994, ApJS, 90, 541
%-546; Jupiter radio bursts and particle acceleration.
%Proc. IAU Symposium #142, in Particle Acceleration
%quoted by MacDowall et al.; Beautiful color plates 1 and 2.
%high-energy particle beam have been observed in close
%association with the QP bursts; an intermediate agent is at
%work, perhaps related to a substorm-like process at Jupiter.
%"Although the phenomena are clearly related in some way
%the large temporal offset (8 minutes) implies that since
%both the waves and particles travel essentially at light
%speed c, there must be an intermediate step or steps
%between wave generation and particle acceleration. The
%particles themselves do not give rise to the radio emission."
%This statement may not be correct!!
%At the time of the observed correlation, Jupiter's magnetosphere
%was undergoing a large-scale compression due to a major enhancement
%in the solar wind density.

\bibitem[]{} Ginzburg V. L., Syrovatskii S. I., 1965, ARA\&A, 3, 297
%Cosmic Magnetobremsstrahlung (Synchrotron Radiation).
%{\it Annu. Rev. Astron. Astrophys.} {\bf 3}, 297 (1965).
%-350 (1965).

\bibitem[]{} Gladstone G. R., et al., 2002, Nature, 415, 1000
%A pulsating auroral X-ray hot spot on Jupiter.
%{\it Nature} {\bf 415}, 1000 (2002).
%-1003 (2002).
%total 15 authors.
%J. H. Waite, Jr., D. Grodent, W. S. Lewis,
%F. J. Crary, R. F. Elsner, M. C. Weisskopf,
%T. Majeed, J.-M. Jahn, A. Bhardwaj,
%J. T. Clarke, D. T. Young, M. K. Dougherty,
%S. A. Espinosa, T. E. Craven
%45-min period; north polar auroral zone.

\bibitem[]{} Gurnett D. A., et al., 2002, Nature, 415, 985 
%--987; 
%W.S. Kurth, G. B. Hospodarsky, A. M. Persoon,
%P. Zarka, A. Lecacheux, S. J. Bolton, M. D. Desch,
%W. M. Farrell, M.L. Kaiser, H.-P. Ladreiter,
%H. O. Rucker, P. Galopeau, P. Louarn,
%D. T. Young, W.R. Pryor, M.K. Dougherty
%Control of Jupiter's radio emission
%and aurorae by the solar wind.

\bibitem[]{} Lou Y. Q., 1994, J. Geophys. Res., 99, 14747 
%``Alfv\'enic Disturbances in the Equatorial Solar
%Wind with a Spiral Magnetic Field", Lou, Y.Q. {\it Journal of
%Geophysical Research}, {\bf 99}, 14,747-14,760, 1994.

\bibitem[]{} Lou Y. Q., 1996, Geophys. Res. Lett., 23, 609
%{\bf 23}, 609 (1996).
%--612; Corotating Shock Accelerated Particles Guided by
%Wavy Spiral Magnetic Fields in the Solar Wind at High
%Heliospheric Latitudes

\bibitem[]{} Lou Y. Q., 2000, ApJ, 540, 1102
%``Rossby-Type Wave Induced Periodicities in Flare Activities 
%and Sunspot Areas or Groups during Solar Maxima", 
%--1108; oddjob directory: rossby/rsbym.gly

\bibitem[]{} Lou Y. Q., 2001, ApJ, 548, 460
%Magnetoinertial oscillations of Jupiter's inner radiation belt.
%{\it Astrophys. J.} {\bf 548}, 460 (2001).
%-465 (2001).

\bibitem[]{} MacDowall  R. J., et al., 1993,
Planet. Space Sci., 41, 1059
%Quasiperiodic Jovian radio bursts: observations
%from the Ulysses Radio and Plasma Wave Experiment.
%{\it Planet. Space Sci.} {\bf 41}, 1059 (1993).
%-1072 (1993).
%1993, Planet. Space Sci., 41, 1059-1072;
%Quasiperiodic Jovian radio bursts: observations
%from the Ulysses Radio and Plasma Wave Experiment
%M. L. Kaiser, M. D. Desch, W. M. Farrell, R. A. Hess,
%R. G. Stone
%beautiful figures 2 and 6 (color).
%a nice histogram in Figure 3.
%quasi-periodic electron acceleration?
%dusk terminator: asymptotically approaching \sim 40 S
%jovigraphic latitude.
%The onset of enhanced 40min burts activity is well
%correlated with the arrival of high-speed solar wind
%streams at Jupiter;
%QP-40 radio bursts -- direction from the south pole.
%15min period during inbound of Ulysses.
%The source locations of QP-15 radio bursts remain uncertain.
%Voyager 1 $\gsmi 0.4$Mev protons with a
%periodicity of $\sim 40$min (pre-dawn magnetosphere outbound pass);
%thousands of QP-40 events during two years following
%the encounter of Jupiter.
%this problem is central to a more complete understanding
%of Jupiter's environment.
%12-15min QP-15 and 30-40min QP40.
%QP-15 bursts were predominantly observed by Ulysses
%during its in-ecliptic approach to Jupiter.
%almost certain the same class of radio burst events observed
%by Voyager Plasma Wave Receiver (PWR) (Kurth et al. 1989)
%cited by MacDowall et al.
%QP-40 almost exclusively outbound from Jupiter -- 40^0S
%of jovigraphic latitude.
%QP-40 bursts and 50kev electrons observed by the Ulysses
%HI-SCALE instrument (Lanzerotti, private communications).
%mentioned electron cyclotron maser instability (Wu and Lee 1979).
%The Ulysses flyby of Jupiter ....
%Unified Radio and Plasma Wave Experiment (URAP).
%The large peak at 2 min occur because the algorithm is
%permitted to detect events in successive frequency
%sweeps and the duration of QP-40 variation is
%significantly longer than 128 seconds.
%delays between successive bursts in a group sometimes
%agree to within a few percent. Subsequent groups of
%bursts may occur with different periods and phases.
%QP-15 both at longitude 0-140 deg are the abrupt onset;
%are similar to the behavior of the "escape" component
%of Jovian nonthermal continuum radiation.
%QP-40 weakly couples with sub-spacecraft longitude.
%They are twice as likely to be observed at $\sim 20$ deg.
%as at $\sim 200$ deg., i.e. they are more likely to be
%observed when the south magnetic pole tips toward Ulysses.
%radio source location at $\sim 5$ R_J
%may be a simple beaming pattern associated with the QP-40 events.
%Certain exciter originate in a region which corotates with
%the planet
%QP-15 \sim 10^7 W per (large) burst; occur in magnetosheath
%(believed by some, e.g. Desch 1994);
%QP-40 \sim 10^8 W per (large) burst.
%explain "Jovian type III bursts" may be inappropriate.
%While Ulysses was inside the Jovian magnetosphere, other
%wave and particle observations indicate similar periodicities.
%URAP capability for determining the direction of arrival and
%polarization of the radio waves.
%also correlate with Kev electrons.
%QP-15 :   26 (or 13) day variability;
%As of Nov.1993---4.5a.u. from Jupiter (out of the ecliptic plane).

\bibitem[]{} McKibben R. B., Simpson J. A.,
Zhang M., 1993, Planet. Space Sci., 41, 1041
%Impulsive bursts of relativistic electrons discovered during
%Ulysses' traversal of Jupiter's dusk-side magnetosphere.
%{\it Planet. Space Sci.} {\bf 41}, 1041 (1993);
%-1058 (1993).
%1993, Planet. Space Sci., 41, 1041
%-1058; Impulsive bursts of relativistic electrons discovered
%during Ulysses' traversal of Jupiter's dusk-side magnetosphere.
%Planetary and Space Science (QC879.A1P7)
%somewhat different from the preprint I have in possession.
%solution of the problem leads to important insights into the
%dynamics of the Jovian magnetopshere.
%electron energies \gsim 8 Mev;
%sometimes radio precedes electron bursts
%HI-SCALE 50 Kev electrons close to kilometric radiation
%cited Lanzerotti for private communications.
%3\times 10^{10}/2\times 10^{5}\sim 1.5 km wavelength.
%Whether QP-40 represent a characteristic period for
%some global oscillations in the magnetosphere that
%interacts with conditions local to the dusk side
%magnetosphere to produce particle acceleration.
%(seems to prefer a global resonance)
%However, periodicity is not exact.
%A significant and surprising finding is that there are
%also periods when no large-scale electron bursts
%actually is present that show evidence for a strong
%\sim 40 min period in the bidirectional anisotropy amplitudes.
%For \gamma=20; B=15\times 10^{-5} G; r_c=2000 km.
%A unidirectional field aligned anisotropy is not consistent
%with a stably trapped population of particles, which would
%display a bidirectional anisotropy which could be either
%field aligned or normal to the field.
%spiky electron bursts;
%enhanced fluxes persist several tens of hours;
%QP-40 bursts were more likely to be observed when the
%South magnetic pole was tipped toward the spacecraft.
%not every electon burst show the strong unidirectional anisotropy.
%large burst \gsim 10^{27} electrons.

\bibitem[]{} Miyoshi Y., et al., 1999, Geophys. Res. Lett, 26, 9 
%Misawa, H., \& Morioka, A. 1999, GRL, 26, 9-12
%Observations of short-term variations of Jupiter's
%synchrotron radiation. 12 yr revolution cycle; a few days
%UV/EUV irradiation. 21cm 20% increase.

\bibitem[]{} Nishida A., 1976, J. Geophys. Res., 81, 1771
%Outward diffusion of energetic particles from the Jovian radiation belt.
%{\it J. Geophys. Res.} {\bf 81}, 1771 (1976).
%-1773 (1976).
%\Journal{1976}{\JGR}{81}{1771}.
%-1773;

\bibitem[]{} Nishida A., Watanabe Y., 1981, 
J. Geophys. Res., 86, 9945
%Joule Heating of the Jovian Ionosphere by Corotation
%Enforcement Currents.
%{\it J. Geophys. Res.} {\bf 86}, 9945 (1981).
%9945-9952 (1981).
%\Journal{1981}{\JGR}{86}{9945}.
%-9952; Joule Heating of the Jovian Ionosphere
%by Corotation Enforcement Currents

\bibitem[]{} Northrop T. G., 1963, The Adiabatic Motion 
of Charged Particles. Interscience Publishers, New York 

\bibitem[]{} Roberts J. A., Berge G. L.,
Bignell R. C., 1984, ApJ, 282, 345
%High-resolution maps of the 1.5 GHz emission from
%Jupiter's disk and radiation belt.
%{\it Astrophys. J.} {\bf 282}, 345 (1984);
%-358 (1984).
%1984, ApJ, 282, 345--358; High-resolution maps of the 1.5 GHz
%emission from Jupiter's disk and radiation belt. many nice figures.

\bibitem[]{} Rogers J. H., 1995, The Giant Planet Jupiter.
Cambridge University Press, Cambridge, England 
%John;
%insubstantial realm of magnetic fields and electrical particles;
%in Jupiter's radiation belt, the trapped particles are some
%tenfold more energetic than in the equatorial belt of Earth;
%several orders of magnitude more abundant;
%Jupiter more rotational constrained than Earth.
%indeed,, in some ways it resembles a low-energy model of a pulsar.
%magnetic field rotates with a period of 9h 55m 29.71s (\pm 0.02s);
%system III longitude;
%the polarity is opposite to that of Earth.
%magnetic field strength 10-14 G at the poles.
%decimetric radiation (discovered in 1958),
%0.1-3m, 3-0.1 GHz, almost steady, total power 2\times 10^9 W,
%synchrotron from radiation belts.
%Table 18.2;

\bibitem[]{} Rybicki G. B., Lightman A. P., 1979,
Radiative Processes in Astrophysics. John Wiley \& Sons, New York

\bibitem[]{} Sault R. J., Oosterloo T., Dulk G. A., 
Leblanc Y., 1997, A\&A, 324, 1190
%{\it Astron. Astrophys.} {\bf 324}, 1190 (1997).
%1997, A\&A, 324, 1190
%-1196; The First Three-Dimensional Reconstruction of
%a Celestial Object at Radio Wavelengths: Jupiter's
%Radiation Belts.

\bibitem[]{} Schardt A. W., McDonald F. B.,
Trainor J. H., 1981, J. Geophys. Res., 86, 8413 
%Energetic particles in the predawn magnetotail of Jupiter.
%{\it J. Geophys. Res.} {\bf 86}, 8413 (1981).
%-8428 (1981).
%--8428; Energetic particles in the predawn magnetotail of Jupiter.
%Voyager 1 and 2; 40 min. period not clearly stated or not obvious.
%somehow other people cited this work for that. The prevalence of
%these phenomena was not apparent from the Voyager observations.

\bibitem[]{} Schultz M., Lanzerotti L. J., 1974, Particle 
Diffusion in the Radiationa Belts. Springer Verlag, New York

\bibitem[]{} Simpson J. A., et al., 1975, Science, 188, 455
%-459; Jupiter revisited: First results from the University
%of Chicago Charged Particle Experiment on Pioneer 11
% Hamilton D C, Lentz G A, McKibben R B, Perkins M. Pyle K R.
% Tuzzolino J, O'Gallagher J J.

\bibitem[]{} Simpson J. A.,  et al., 1992, Science, 257, 1543
%Energetic charged-particle phenomena in the Jovian magnetosphere:
%First results from Ulysses COSPIN collaboration.
%{\it Science} {\bf 257}, 1543 (1992);
%-1550 (1992).
%1992, Science, 257, 1543-1550;
%Energetic charged-particle phenomena in the Jovian magnetosphere:
%First results from Ulysses COSPIN collaboration
%J. D. Anglin, A. Balogh, I. R. Burrows, S.W.H. Cowley,
%P. Ferrando, B. Heber, R. J. Hynds, H. Kunow, R. G. Marsden,
%R. B. McKibben, R. M\"uller-Melin, D. E. Page, A. Raviart,
%T. R. Sanderson, K. Staines, K.-P. Wenzel, Margret D. Wilson,
%M. Zhang.
%40 min. period relativistic electron bursts and radio bursts.

\bibitem[]{} Stone R. G., et al., 1992, Science, 257, 1524
%Stone, R. G. {\it et al.} Ulysses radio
%and plasma wave observations in the Jupiter environment.
%{\it Science} {\bf 257}, 1524-1531 (1992).
%B. M. Pedersen, C. C. Harvey, P. Canu, N. Cornilleau-Wehrlin,
%M. D. Desch, C. de Villedary, J. Fainberg, W. M. Farrell,
%K. Goetz, R. A. Hess, S. Hoang, M. L. Kaiser, P. J. Kellogg,
%A. Lecacheux, N. Lin, R. J. MacDowall, R. Manning,
%C. A. Meetre, N. Meyer-Vernet, M. Moncuquet,
%V. Osherovich, M. J. Reiner, A. Tekle, J. Thiessen, P. Zarka


\bibitem[]{} Walt M., 1994, Introduction to Geomagnetically
Trapped Radiation. Cambridge University Press, Cambridge

\bibitem[]{} Zhang M., et al., 1995,
J. Geophys. Res., 100, 19497
%Impulsive bursts of energetic particles in the high-latitude
%duskside magnetosphere of Jupiter.
%{\it J. Geophys. Res.} {\bf 100}, 19,497 (1995);
%-19,512 (1995).
%McKibben R. B., Simpson J. A., Cowley S. W. H., Staines K.,
%Anglin J. D., Marsden R. G., Sanderson T. R., Wenzel K.-P.

\bibitem[]{} Zhang M., Simpson J. A., McKibben R. B.,
1993, Planet. Space Sci., 41, 1029
%Relativistic electron flux anisotropies in the dusk-side Jovian
%magnetosphere: A test for source location and escape mechanism.
%{\it Planet. Space Sci.} {\bf 41}, 1029 (1993).
%-1040 (1993).
%Relativistic electron flux anisotropies in the dusk-side Jovian
%magnetosphere: A test for source location and escape mechanism.
%Planetary and Space Science
%$\gsim 3$Mev electron flux; 40 -- 45 days of 1992;
%electron flux $\gsim 10^{26}\hbox{ s}^{-1}$;
%a fraction of interplanetary Jovian electrons may escape
%the magnetosphere in this way.
%Jupiter is a strong source of relativistic electrons
%propagating in the interplanetary space.
%Nishida (1976) circulation model tested. generally in favor;
%inward diffusion of solar wind electron for energy gains;
%outward diffusion from IRB do not degrade energy;
%pitch angle of e \sim 90 deg for low L.
%polar leakage is another means of getting relativistic
%electrons out (what is the fraction?); someone mentioned
%relativistic electron jets.

\end{thebibliography}