Swift Observations of GRB 200412B

K.L. Page (U. Leicester) and B. Sbarufatti (PSU) for the Swift team

1. Introduction

Longo et al. (GCN Circ. 27557) reported the GRB detection. 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 Sbarufatti et al. (GCN Circ. 27600).

XRT data now comprise 6.1 ks of Photon Counting data covering times from T+20 ks to T+370 ks.

The light curve (Figure 2) is best fit by a power-law with decay index 1.6 ± 0.3. We thus confirm that this is indeed the afterglow of GRB 200412B. The latest results can be viewed via: https://www.swift.ac.uk/xrt_curves/00020981/

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
18h33m15.21s +62°31'57.1" 2.5" XRT Page et al. GCN Circ. 27561

Table 1. Positions from the Swift instruments.

Band Authors GCN Circ. Subject Observatory Notes
Optical Lipunov et al. 27549 Fermi GRB 200412B: Global MASTER-Net
observations report 		MASTER
Optical Lipunov et al. 27555 MASTER Optical Couterpart in Gagarin
day! 		MASTER
Optical Lipunov et al. 27556 MASTER-Amur Optical Couterpart in
Gagarin day! 		MASTER
Optical 27564 Optical afterglow detection with 1.3m
DFOT		 detection
Optical Kumar et al. 27563 Optical afterglow detection with 1.3m
DFOT		 Nainital detection
Optical Belkin et al. 27566 AbAO optical observations Abastumani Astro. Obs. detection
Optical Stecklum et al. 27567 Tautenburg observations Tautenburg detection
Optical Moskvitin 27570 SAO RAS observations of OT SAO RAS
Optical Xin et al. 27571 Xinglong TNT optical observations TNT detection
Optical Belkin et al. 27574 contunued AbAO optical observations Abastumani Astro. Obs. detection
Optical Klose et al. 27575 Tautenburg observations Tautenburg
Optical Ogawa et al. 27576 MITSuME Akeno optical observation MITSuME Akeno detection
Optical Stecklum et al. 27582 continued Tautenburg observations Tautenburg light curve
Optical Belkin et al. 27583 Mondy optical observations Mondy detection
Optical Klose et al. 27593 continued Tautenburg observations Tautenburg light curve
Optical Kumar et al. 27598 GROWTH India detection of afterglow GROWTH-India detection
Optical Belkin et al. 27604 continued AbAO, Mondy, TSHAO, Terskol
optical observations		 Abastumani Astro. Obs. light curve
Optical Belkin et al. 27605 continued Terskol optical observations Terskol marginal detection
Optical Belkin et al. 27610 continued Mondy and Terskol optical
observations		 Mondy detection
Optical Kumar et al. 27653 Gagarin-day GRB 200412B: observations
with the 3.6m Devasthal Optical
Telescope		 Devasthal Opt.Tel.
Gamma-ray Fermi 27547 Fermi GBM Final Real-time Localization Fermi GBM
Gamma-ray Burgess et al. 27548 BALROG localization (Fermi Trigger
608375325 / GRB 200412381)		 BALROG
Gamma-ray Longo et al. 27557 Fermi-LAT detection Fermi LAT Emax=1.1 GeV
Gamma-ray Mailyan and Hamburg 27558 Fermi GBM detection Fermi GBM Epeak=257±4 keV
T90=6 seconds
Fluence=8.00±0.04x10-5erg cm-2
(97.0 percentile for long GRBs)
Gamma-ray Gupta et al. 27563 AstroSat CZTI detection CZTI
Gamma-ray Zheng et al. 27565 Insight-HXMT/HE detection Insight-HXMT T90=5.50 seconds
Gamma-ray Tamura et al. 27572 CALET Gamma-Ray Burst Monitor detection CALET
Gamma-ray Ridnaia et al. 27581 Konus-Wind observation Konus-Wind Epeak=289 (-16,+16) keV
Duration=~30.5 seconds
Fluence=1.12(-0.05,+0.05)x10-4erg cm-2

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

Table 3. Found no UVOT observations.

April 27, 2020