J/A+A/650/A83 Radio flux densities of neutrino associations (Hovatta+, 2021)
Association of IceCube neutrinos with radio sources observed at Owens Valley
and Metsahovi Radio Observatories.
Hovatta T., Lindfors E., Kiehlmann S., Max-Moerbeck W., Hodges M,
Liodakis I., Lahteenmaki A., Pearson T.J., Readhead A.C.S., Reeves R.A.,
Suutarinen S., Tammi J., Tornikoski M.
<Astron. Astrophys. 650, A83 (2021)>
=2021A&A...650A..83H 2021A&A...650A..83H (SIMBAD/NED BibCode)
ADC_Keywords: Radio continuum ; BL Lac objects ; QSOs
Keywords: neutrinos - BL Lacertae objects: general - quasars: general -
galaxies: jets - radio continuum: galaxies
Abstract:
Identifying the most likely sources for high-energy neutrino emission
has been one of the main topics in high-energy astrophysics ever since
the first observation of high-energy neutrinos by the IceCube Neutrino
Observatory. Active galactic nuclei with relativistic jets, also known
as blazars, have been considered to be one of the main candidates
because of their ability to accelerate particles to high energies. We
study the connection between radio emission and IceCube neutrino
events using data from the Owens Valley Radio Observatory (OVRO) and
Metsahovi Radio Observatory blazar monitoring programs. We identify
sources in our radio monitoring sample that are positionally
consistent with IceCube high-energy neutrino events. We estimate their
mean flux density and variability amplitudes around the neutrino
arrival time, and compare these with values from random samples to
establish the significance of our results. We find radio source
associations within our samples with 15 high-energy neutrino events
detected by IceCube. Nearly half of the associated sources are not
detected in the γ-ray energies, but their radio variability
properties and Doppler boosting factors are similar to the
γ-ray detected objects in our sample, meaning that they could
still be potential neutrino emitters. We find that the number of
strongly flaring objects in our statistically complete OVRO samples is
unlikely to be a random coincidence (at 2σ level). Based on our
results, we conclude that although it is clear that not all neutrino
events are associated with strong radio flaring blazars, observations
of large-amplitude radio flares in a blazar at the same time as a
neutrino event are unlikely to be a random coincidence.
Description:
Radio flux densities of the sources associated with IceCube neutrino
events. Flux densities at 15GHz are obtained by the Owens Valley
Radio Observatory for 20 sources. Flux densities at 37GHz are
obtained by the Metsahovi Radio Observatory for 7 sources. For each
source there are multiple measurements and the observed time in MJD,
the flux density and its uncertainty are given.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
sources.dat 58 21 List of studied sources
fluxdens.dat 61 15205 Flux densities at 15 and 37GHz
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Byte-by-byte Description of file: sources.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Name J2000 Name of the target (JHHMM+DDMM)
12- 13 I2 h RAh Simbad Right Ascension (J2000.0)
15- 16 I2 min RAm Simbad Right Ascension (J2000.0)
18- 22 F5.2 s RAs Simbad Right Ascension (J2000.0)
24 A1 --- DE- Simbad Declination sign (J2000.0)
25- 26 I2 deg DEd Simbad Declination (J2000.0)
28- 29 I2 arcmin DEm Simbad Declination (J2000.0)
31- 34 F4.1 arcsec DEs Simbad Declination (J2000.0)
36- 38 I3 --- N15GHz ? Number of 15GHz flux density measurements
in fluxdens.dat file
40- 43 I4 --- N37GHz ? Number of 37GHz flux density measurements
in fluxdens.dat file
45- 58 A14 --- SName Simbad name
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Byte-by-byte Description of file: fluxdens.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Name J2000 Name of the target (JHHMM+DDMM)
12- 25 A14 --- OName Alias of the name
27- 28 I2 GHz Freq [15/37] Frequency of the observation
30- 40 F11.5 d MJD Modified Julian date of the observation
42- 46 F5.2 Jy S Flux density
48- 51 F4.2 Jy e_S 1-sigma uncertainty of the flux density
53- 61 A9 --- Tel Instrument used for observation
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Acknowledgements:
Talvikki Hovatta, talvikki.hovatta(at)utu.fi
(End) Patricia Vannier [CDS] 09-Apr-2021