Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A multi-site campaign to measure solar-like oscillations in Procyon. I.
  Observations, Data Reduction and Slow Variations   We have carried out a multi-site campaign to measure oscillations in the F5
star Procyon A. We obtained high-precision velocity observations over more than
three weeks with eleven telescopes, with almost continuous coverage for the
central ten days. This represents the most extensive campaign so far organized
on any solar-type oscillator. We describe in detail the methods we used for
processing and combining the data. These involved calculating weights for the
velocity time series from the measurement uncertainties and adjusting them in
order to minimize the noise level of the combined data. The time series of
velocities for Procyon shows the clear signature of oscillations, with a
plateau of excess power that is centred at 0.9 mHz and is broader than has been
seen for other stars. The mean amplitude of the radial modes is 38.1 +/- 1.3
cm/s (2.0 times solar), which is consistent with previous detections from the
ground and by the WIRE spacecraft, and also with the upper limit set by the
MOST spacecraft. The variation of the amplitude during the observing campaign
allows us to estimate the mode lifetime to be 1.5 d (+1.9/-0.8 d). We also find
a slow variation in the radial velocity of Procyon, with good agreement between
different telescopes. These variations are remarkably similar to those seen in
the Sun, and we interpret them as being due to rotational modulation from
active regions on the stellar surface. The variations appear to have a period
of about 10 days, which presumably equals the stellar rotation period or,
perhaps, half of it. The amount of power in these slow variations indicates
that the fractional area of Procyon covered by active regions is slightly
higher than for the Sun.

20
The categories of this paper are: acc-phys
15
The categories of this paper are: nucl-ex
32
The categories of this paper are: atom-ph
16
The categories of this paper are: stat
33
The categories of this paper are: plasm-ph
35
The categories of this paper are: mtrl-th
7
The categories of this paper are: hep-th
14
The categories of this paper are: math-ph
12
The categories of this paper are: nucl-th
37
The categories of this paper are: supr-con
10
The categories of this paper are: q-bio
13
The categories of this paper are: quant-ph
21
The categories of this paper are: adap-org
3
The categories of this paper are: physics
0
The categories of this paper are: hep-ph
23
The categories of this paper are: solv-int