VLASS identifies possible radio counterparts to IceCube-201130A, including 2 blazars

ATel #14235; Gregory R. Sivakoff (University of Alberta)
on 1 Dec 2020; 01:47 UT
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Credential Certification: Gregory R Sivakoff (sivakoff@ualberta.ca)

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IceCube-201130A is a recently detected (gold-track) astrophysical neutrino (GCN #28969), localized at 90% PSF containment to (J2000):
RA: 30.54 (+1.13/-1.31) deg
Dec: -12.10 (+1.15/-1.13) deg

Here, we present potential counterparts with precursor radio emission at 2-4 GHz from the catalog of the Very Large Array Sky Survey Epoch 1 Quick Look Components catalog (Gordon et al. 2020, RNAAS, 4, 175). The IceCube containment region saddles Tile boundaries in VLASS Epoch 1 such that precursor observations were performed on 4 dates: 2017 Nov 12; 2017 Nov 26; 2019 May 19, 2019 June 21. We identify 176 components in the above (90% PSF containment) region, excluding catalog components with "Duplicate_flag" >=2 and "Quality" !=0. We highlight the two brightest components in particular: VLASS1QLCIR J020157.15-113232.6 (with a peak radio flux density of 1194.1 +/- 1.1 mJy, with a much larger likely systematic flux density error due to dynamic range limits in the Quick Look images); and VLASS1QLCIR J020626.11-115039.2 (with a peak radio flux density of 186.0 +/- 0.3 mJy).

VLASS1QLCIR J020157.15-113232.6 is better known as the core of 3C 57 (and WISE J020157.18-113233.5), which was identified as having about equal likelihood of being associated with a flat spectrum radio quasar blazar or a mixed candidate (BL Lac/FSRQ) blazar, such that it is identified as being a mixed class candidate blazar (D'Abrusco et al. 2014, ApJS, 215, 14). Simbad also classifies this galaxy as a (radio loud) Seyfert 1 galaxy. This source is approximately 34 arcmin away from the centre of the IC 20201130A position. This may be the brightest potential radio component to an IceCube neutrino to date. We adopt the Gaia DR2 position for the source:
RA: 30.488247438 +/- 0.000000022 deg
Dec: -11.542621436 +/- 0.000000014 deg.

VLASS1QLCIR J020626.11-115039.2 is highly likely to be the radio counterpart to the one Fermi-LAT 4FGL source inside the 90% localization region, 4FGL J0206.4-1151. The more localized electromagnetic counterpart, also known as PMN J0206-1150, is one of the Fermi blazars monitored by the MOJAVE survey (Lister et al 2018, ApJS, 234, 12). For consistency, we adopt the Gaia DR2 position for the source:
RA: 31.60868663 +/- 0.00000013 deg
Dec: -11.844368005 +/- 0.000000096 deg.

Given this potential radio source associated with 2 candidate blazars, one that is a rare source above core source brighter than 1 Jansky and the other that is a known Fermi source, we strongly suggest multi-wavelength observations of both sources. For completeness, we list the brightest VLASS components (by peak flux density), where the position to 0.5" accuracy is indicated by the name:

 
 VLASS1QLCIR J015819.29-120234.7; (46.91+/-0.19) mJy 
 VLASS1QLCIR J020157.43-113234.6; (46.57+/-1.07) mJy 
 VLASS1QLCIR J020509.70-113522.0; (34.04+/-0.21) mJy 
 VLASS1QLCIR J020157.55-113244.9; (31.43+/-1.09) mJy 
 VLASS1QLCIR J020254.62-114031.5; (27.94+/-0.22) mJy 
 VLASS1QLCIR J020232.78-124847.0; (27.71+/-0.19) mJy 
 VLASS1QLCIR J020511.68-113509.8; (23.39+/-0.21) mJy 
 VLASS1QLCIR J020228.39-130609.5; (23.28+/-0.18) mJy 
 VLASS1QLCIR J020027.75-125847.0; (21.31+/-0.18) mJy 
 VLASS1QLCIR J020119.07-111849.3; (20.13+/-0.24) mJy 
 VLASS1QLCIR J020304.13-123308.9; (19.82+/-0.21) mJy 
 VLASS1QLCIR J020115.77-130218.7; (18.83+/-0.18) mJy 
 VLASS1QLCIR J020119.79-111916.2; (16.86+/-0.24) mJy 
 VLASS1QLCIR J020200.43-122138.3; (15.47+/-0.18) mJy 
 VLASS1QLCIR J020228.25-130611.7; (14.32+/-0.18) mJy 
 VLASS1QLCIR J015957.19-112637.2; (14.26+/-0.21) mJy 
 VLASS1QLCIR J015952.46-122255.5; (14.25+/-0.17) mJy 
 VLASS1QLCIR J015736.97-121448.2; (14.06+/-0.12) mJy 
 VLASS1QLCIR J020406.64-114906.5; (12.66+/-0.19) mJy 
 VLASS1QLCIR J020305.10-123312.5; (12.32+/-0.21) mJy 
 VLASS1QLCIR J020046.16-124833.0; (12.06+/-0.17) mJy 
 VLASS1QLCIR J020347.97-114239.6; (11.26+/-0.17) mJy 

Link to site for CIRADA cutout service and VLASS catalog