[vsnet-grb-info 26891] Swift follow-up observations of the flat spectrum radio quasar PMN J0206-1150 in the error region of IceCube-201130A

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  28994
SUBJECT: Swift follow-up observations of the flat spectrum radio quasar PMN J0206-1150 in the error region of IceCube-201130A
DATE:    20/12/04 19:32:33 GMT
FROM:    Timothee Gregoire at Penn State  <tmg5746 at psu.edu>

T. Gregoire (PSU), F. D'Ammando (INAF-IRA Bologna), D. B. Fox (PSU),
A. Keivani (Columbia U.), J. P. Osborne (U. Leicester), F. Krauss
(PSU), P. A. Evans (U. Leicester), J. A. Kennea (PSU), H. A. Ayala
Solares (PSU), D. F. Cowen (PSU) and J. DeLaunay (PSU)

We report on continuing Swift observations of the flat spectrum radio
quasar PMN J0206-1150, associated with the gamma-ray source 4FGL
J0206.4-1151 (Abdollahi et al. 2020, ApJS, 247, 33), the Fermi-LAT
source closest to the location of IceCube 201130A (IceCube
Collaboration; GCN Circ. 28969). After the first Swift observation
performed on 2020 December 1 (ATel #14240, GCN Circ. 28979), the
source has been observed again by Swift between 20:39 UT on 2020
December 2 and 11:24 UT on 2020 December 3 for a total of 3.9 ks.

The source has been detected by XRT with a net count rate of (2.2 +/-
0.9)e-3 cps. As a comparison, the net count rate of the source on
December 1 was (3.1 +/- 0.9)e-3 cps, showing a mild decrease of the
source activity in X-rays.

Assuming a photon index of 1.7, as observed on December 1, and fitting
the X-ray spectrum with an absorbed power law model with a HI column
density consistent with the Galactic value in the direction of the
source (n_H = 1.7 x 10^20 cm^-2, Ben Bekhti N. et al., 2016, A&A, 594,
A116), we obtain a 0.3-10 keV flux (unabsorbed) of 4.1 (+2.4, -2.0) x
10^-14 erg cm^-2 s^-1.

Simultaneous UVOT observations were performed on 2020 December 2-3 and
the source is detected above 3 sigma in all UVOT filters, except for
the V filter. The measured magnitudes (Vega system) are V > 19.46, B =
19.60 +/- 0.18, U = 18.72 +/- 0.16, W1 = 18.93 +/- 0.15, M2 = 19.17
+/- 0.10, and W2 = 19.21 +/- 0.12. Differently from the X-ray band, a
moderate brightening has been observed from U to M2 filters on
December 2-3 with respect to December 1.

In GCN Circ. 28979 [and ATel #14240] we wrongly reported that the X-ray
source detected by XRT was 2.8 arcmin from the position of PMN
J0206-1150, while it should be 2.8 arcsec.