Swift Observations of GRB 201214A

J.A. Kennea (PSU) for the Swift team

1. Introduction

Mereghetti et al. (GCN Circ. 29037) reported the GRB detection. A gamma ray burst lasting about 150 s has been detected by IBAS in the IBIS/ISGRI data at 6:18:20 UT of 14 December 2020. Table 1 contains the best reported positions from Swift.

Table 2 is a summary of GCN Circulars about this GRB from observatories other than Swift.

2. BAT Observations and Analysis

BAT did not observe this burst.

3. XRT Observations and Analysis

Analysis of the initial XRT data was reported by Kennea et al. (GCN Circ. 29092). The source previously reported by Kennea et al. (GCN Circ. 29048), "Source 2", is fading with 3-sigma significance, and is therefore likely the GRB afterglow. The source is fading with α >0.6.

A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 2.7 (+0.9, -0.7). The best-fitting absorption column is 1.9 (+2.2, -1.6) x 10²¹ cm^-2, in excess of the Galactic value of 2.4 x 10²⁰ cm^-2 (Willingale et al. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 2.6 x 10^-11 (2.6 x 10^-11) erg cm^-2 count^-1.

4. UVOT Observations and Analysis

UVOT results are not available.

Figure 1. The BAT light curve is not available.

RA (J2000) Dec (J2000) Error Note Reference

11^h23^m41.87^s +33°52'09.5" 2.2" XRT Kennea et al. GCN Circ. 29092

Table 1. Positions from the Swift instruments.

Band Authors GCN Circ. Subject Observatory Notes

Optical Lipunov et al. 29035 Integral GRB201214.26: Global
MASTER-Net observations report MASTER

Optical Jelinek et al. 29040 Mates' birthday GRB optical limit from
FRAM-ORM FRAM upper limits

Optical Kumar et al. 29091 1.3m DFOT, optical upper limits Devasthal Opt.Tel. upper limits

Optical Belkin et al. 29093 TSHAO optical upper limit Zeiss-1000 upper limits

Gamma-ray Mereghetti et al. 29037 A long GRB detected by INTEGRAL INTEGRAL Fluence=5x10^-7erg cm^-2

Table 2. Summary of GCN Circulars from other observatories sorted by band and then circular number.

RA (J2000)	Dec (J2000)	Error	Note	Reference
11^h23^m41.87^s	+33°52'09.5"	2.2"	XRT	Kennea et al. GCN Circ. 29092

Band	Authors	GCN Circ.	Subject	Observatory	Notes
Optical	Lipunov et al.	29035	Integral GRB201214.26: Global MASTER-Net observations report	MASTER
Optical	Jelinek et al.	29040	Mates' birthday GRB optical limit from FRAM-ORM	FRAM	upper limits
Optical	Kumar et al.	29091	1.3m DFOT, optical upper limits	Devasthal Opt.Tel.	upper limits
Optical	Belkin et al.	29093	TSHAO optical upper limit	Zeiss-1000	upper limits
Gamma-ray	Mereghetti et al.	29037	A long GRB detected by INTEGRAL	INTEGRAL	Fluence=5x10^-7erg cm^-2

December 20, 2020