GRB 220514B

Y. Kawakubo (LSU), M. Serino (AGU), H. Negoro, 
 M. Nakajima, K. Kobayashi, M. Tanaka, Y. Soejima (Nihon U.), 
 T. Mihara, T. Kawamuro, S. Yamada, T. Tamagawa, M. Matsuoka (RIKEN), 
 T. Sakamoto, S. Sugita, H. Hiramatsu, A. Yoshida (AGU), 
 Y. Tsuboi, W. Iwakiri, J. Kohara (Chuo U.), 
 M. Shidatsu, M. Iwasaki (Ehime U.),
 N. Kawai, M. Niwano, R. Hosokawa, Y. Imai, N. Ito, Y. Takamatsu (Tokyo Tech), 
 S. Nakahira, S. Ueno, H. Tomida, M. Ishikawa, M. Tominaga, T. Nagatsuka, T. Kurihara (JAXA), 
 Y. Ueda, S. Ogawa, K. Setoguchi, T. Yoshitake, K. Inaba (Kyoto U.), 
 H. Tsunemi (Osaka U.), 
 M. Yamauchi, Y. Nonaka, T. Sato, R. Hatsuda, R. Fukuoka (Miyazaki U.), 
 K. Yamaoka (Nagoya U.),
 M. Sugizaki (NAOC)
 report on behalf of the MAXI team:
 
The MAXI/GSC nova alert system triggered a bright uncatalogued 
X-ray transient source at 23:24:21 UT on 2022 May 14.
Assuming that the source flux was constant over the transit,
we obtain the source position at
(R.A., Dec) = (246.864 deg, 61.440 deg) = (16 27 27, +61 26 23) (J2000) 
with a statistical 90% C.L. elliptical error region 
with long and short radii of 0.26 deg and 0.24 deg, respectively. 
The roll angle of long axis from the north direction is 101.0 deg counterclockwise. 
There is an additional systematic uncertainty of 0.1 deg (90% containment radius).
Without assumptions on the source constancy, we obtain a rectangular error
box for the transient source with the following corners:
(246.141, 61.757) deg = (16 24 33, +61 45 25) (J2000) 
(245.940, 61.286) deg = (16 23 45, +61 17 09) (J2000) 
(248.119, 61.055) deg = (16 32 28, +61 03 17) (J2000) 
(248.352, 61.523) deg = (16 33 24, +61 31 22) (J2000) 
The X-ray flux averaged over the scan was 168 +- 26 mCrab
(4.0-10.0keV, 1 sigma error).
There was no significant excess flux in the previous transit at 05/14 21:51 UT 
with an upper limit of 20 mCrab.

P. A. Evans (U. Leicester) reports on behalf of the Swift team:

Swift has initiated a series of observations, tiled on the sky, of the
MAXI GRB 220514B. Automated analysis of the XRT data will
be presented online at http://www.swift.ac.uk/xrt_products/TILED_GRB00106

Any uncatalogued X-ray sources detected in this analysis will be
reported on this website and via GCN COUNTERPART notices. The probability of finding
serendipitous sources, unrelated to the MAXI event is high: any X-ray source
considered to be a probable afterglow candidate will be reported via a GCN Circular
after manual consideration.

Details of the XRT automated analysis methods are detailed in Evans et
al. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8).

This circular is an official product of the Swift-XRT team.

A. D'Ai (INAF-IASFPA), J. D. Gropp (PSU), J.A. Kennea (PSU), A.
Tohuvavohu (U. Toronto), J.P. Osborne (U. Leicester), K.L. Page (U.
Leicester), A. Melandri (INAF-OAB), T. Sbarrato (INAF-OAB) and P.A.
Evans (U. Leicester) report on behalf of the Swift-XRT team:

Swift-XRT has performed follow-up observations of the MAXI-detected
burst GRB 220514B (Y. Kawakubo et al. GCN Circ. 32046
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 ) in a series of
observations tiled on the sky. The total exposure time is 1.9 ks,
distributed over 4 tiles; the maximum exposure at a single sky location
was 1.0 ks. The data were collected between T0+57.9 ks and T0+60.1 ks,
and are entirely in Photon Counting (PC) mode. 

No X-ray sources have been detected. The 3-sigma upper limit in the
field (not including the regions where the tiles overlap) ranges from
~0.02 to ~0.04 ct s^-1, corresponding to a 0.3-10 keV observed flux of
6.7e-13 to 1.4e-12 erg cm^-2 s^-1 (assuming a typical GRB spectrum).

The results of the XRT-team automatic analysis of the tiled XRT
observations, including a position-specific upper limit calculator, are
available at https://www.swift.ac.uk/xrt_products/TILED_GRB00106.

This circular is an official product of the Swift-XRT team.

A.Ridnaia, D. Frederiks, A.Lysenko, D. Svinkin,
A. Tsvetkova,  M. Ulanov, and T. Cline,
on behalf of the Konus-Wind team, report:

The long GRB 220514B
(MAXI/GSC detection: Kawakubo et al., GCN Circ. 32046
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 )
was detected by Konus-Wind (KW) in the waiting mode.

A Bayesian block analysis of the KW waiting mode data in
the 20-1500 keV band reveals a ~10 sigma count rate increase
over background in the interval from ~T0-26 s to ~T0+74 s,
where T0 = T0(MAXI) = 84261 s UT (23:24:21).

The K-W light curve of this burst is available at
http://www.ioffe.ru/LEA/GRBs/GRB220514B/

As observed by Konus-Wind, the burst had a fluence of
6.59(-1.19,+1.61)x10^-6 erg/cm2 and a 2.944-s peak flux,
measured from ~T0-14.4 s, of 1.54(-0.43,+0.50)x10^-7 erg/cm2/s
(both in the 20 - 1500 keV energy range).

Modeling the K-W 3-channel time-integrated spectrum
(from ~T0-26.2 s to ~T0+73.9 s)
by a power law with exponential cutoff (CPL) model
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
yields alpha = -0.82(-0.21,+0.33) and Ep = 263(-65,+112) keV.

All the quoted errors are estimated at the 1 sigma confidence level.
All the presented results are preliminary.