Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Multi-Frequency Observations of the Candidate Neutrino Emitting Blazar
  BZB J0955+3551   The recent spatial and temporal coincidence of the blazar TXS 0506+056 with
the IceCube detected neutrino event IC-170922A has opened up a realm of
multi-messenger astronomy with blazar jets as a plausible site of cosmic-ray
acceleration. After TXS 0506+056, a second blazar, BZB J0955+3551, has recently
been found to be spatially coincident with the IceCube detected neutrino event
IC-200107A and undergoing its brightest X-ray flare measured so far. Here, we
present the results of our multi-frequency campaign to study this peculiar
event that includes observations with the NuSTAR, Swift, NICER, and 10.4 m Gran
Telescopio Canarias (GTC). The optical spectroscopic observation from GTC
secured its redshift as $z=0.55703^{+0.00033}_{-0.00021}$ and the central black
hole mass as 10$^{8.90\pm0.16}~M_{\odot}$. Both NuSTAR and NICER data reveal a
rapid flux variability albeit at low-significance ($\lesssim3.5\sigma$). We
explore the origin of the target photon field needed for the photo-pion
production using analytical calculations and considering the observed
optical-to-X-ray flux level. We conclude that seed photons may originate from
outside the jet, similar to that reported for TXS 0506+056, although a scenario
invoking a co-moving target photon field (e.g., electron-synchrotron) can not
be ruled out. The electromagnetic output from the neutrino-producing
photo-hadronic processes are likely to make only a sub-dominant contribution to
the observed spectral energy distribution suggesting that the X-ray flaring
event may not be directly connected with IC-200107A.

3
The categories of this paper are: physics
35
The categories of this paper are: mtrl-th
32
The categories of this paper are: atom-ph
37
The categories of this paper are: supr-con
9
The categories of this paper are: nlin
28
The categories of this paper are: alg-geom
24
The categories of this paper are: dg-ga
34
The categories of this paper are: chem-ph
20
The categories of this paper are: acc-phys
31
The categories of this paper are: ao-sci
29
The categories of this paper are: funct-an
4
The categories of this paper are: cond-mat
27
The categories of this paper are: comp-gas
36
The categories of this paper are: cmp-lg
7
The categories of this paper are: hep-th
19
The categories of this paper are: eess