Swift Trigger: 958733

Presumed name: GRB 200228B

BAT	16^h 48^m 06.24^s, +16° 57′ 36.0″
position:	(252.026, +16.960 ± 180″)
XRT	16^h 48^m 11.35^s, +16° 59′ 06.0″
position:	(252.0473, +16.9850 ± 5.7″)
UVOT	No position available.
Galactic N_HI:	5.00×10⁰ cm^-2
Galactic E(B-V):	0.076 mag

Best RA:	16^h 48^m 11.35^s	= 252.0473 d
Best Dec:	+16° 59′ 06.0″	= +16.9850 d

Gal Lat:	34.69
Gal Long:	35.48

Sun angle:	91.07°, 5.9 hr West

¹Onboard position

GCN Notices for this burst.

View this region in Aladin.

Observability of this burst for Swift.

Sun angle for this burst.

UVOT data

No UVOT images are currently available.

XRT SPER data

SPER results page for this trigger.

There are 1 SPER messages, and 1 objects have been found

- Object 1
- RA (J2000) : 16 48 11.35 ( 252.04730)
- Dec (J2000): +16 59 06.2 ( 16.98505)
- Error (90%): 5.746"
- Counts in Source: 10

See the SPER page for details of how this position was produced.

Known transients within 5′ of the GRB

Click on the offset to view the transient announcement.

Offset (′′)	RA	Dec	Source	Misc
0.2′′	252.04730	16.98505	GCN #27254	GRB 200228B: Swift detection of a burst
3.1′′	252.04642	16.98522	GCN #27256	GRB 200228B: Enhanced Swift-XRT position
6.9′′	252.04533	16.98458	GCN #27276	GRB 200228B: Mondy� TSHAO� AbAO and CrAO optical observations� afterglow candidate
156.6′′	252.00750	16.96397	GCN #27273	GRB 200228B: Swift-BAT refined analysis

Catalogue Searches. Searched 3.33′ around XRT position

Click on the distance to view the full details (not available for sources from the SSS catalogue). Click on the column headers to sort the table on that column (click again to invert sort order).

SIMBAD

	RA*	Dec*	SIMBAD name		Query
189.2	252.0179	17.0294	TYC 1525-702-1	B=12.48, G=11.6953, H=10.378, J=10.671, K=10.336, V=11.85

* RA/Dec in equinox J2000

X-ray sources

	RA*	Dec*		Source table²	Observatory	Query

Queried the X-ray MASTER catalogue.

* RA/Dec in equinox J2000

¹Energy band for count-rate is mission specific.

Galaxies

	RA*	Dec*		Catalogue
11.1	252.0504	16.9856		NED
11.7	252.0438	16.9853		NED
16.3	252.0508	16.9822		NED
19.0	252.0518	16.9819	R=23.1, g=24.3, i=22.0, u=25.1, z=20.9	SDSS
21.0	252.0413	16.9859	R=21.5, g=22.0, i=20.0, u=21.9, z=20.3	SDSS
21.5	252.0412	16.9858		NED
21.8	252.0454	16.9908		NED
22.2	252.0456	16.9909	R=20.3, g=20.9, i=20.0, u=21.8, z=20.0	SDSS
23.8	252.0404	16.9847	R=23.4, g=25.9, i=21.3, u=24.4, z=22.0	SDSS
24.2	252.0436	16.9793	B1=21.3, B2=21.2, R2=20.5	USNO-B1

Queried APM-N, SDSS, PSCz, SSS, NED, 2MASSX, USNO-B1.

There are 476 galaxies within the position error. The full list is here.

* RA/Dec in equinox J2000

Magnitudes depend on the catalogue. e.g. For Sloan, R is the Sloan r mag, not the Johnson R from APM, for example

Stars

	RA*	Dec*		Catalogue
10.6	252.0503	16.9856	I=17.7, R=18.2, g=19.3, u=21.8, z=17.5	SDSS
10.6	252.0503	16.9857	B1=19.7, B2=19.2, I=17.4, R1=18.3, R2=17.7	USNO-B1
11.1	252.0505	16.9855	h=15.8, j=16.2, k=15.5	2MASS
12.6	252.0437	16.9855	I=22.0, R=23.0, g=24.4, u=24.5, z=21.4	SDSS
12.7	252.0484	16.9884	I=20.0, R=20.5, g=21.7, u=24.7, z=19.6	SDSS
15.6	252.0518	16.9849	I=22.2, R=23.2, g=25.7, u=24.2, z=21.2	SDSS
20.2	252.0420	16.9826	I=20.6, R=20.6, g=20.9, u=21.9, z=20.6	SDSS
20.2	252.0420	16.9826	B1=21.1, B2=20.6	USNO-B1
22.3	252.0456	16.9910	B1=21.3, B2=20.9, I=19.0, R1=20.1, R2=20.2	USNO-B1
25.8	252.0399	16.9861	I=20.7, R=22.1, g=24.1, u=23.8, z=20.0	SDSS

Queried USNO-B1, SDSS, 2MASS.

There are 407 stars within the position error. The full list is here.

* RA/Dec in equinox J2000

Magnitudes depend on the catalogue. e.g. For Sloan, R is the Sloan r mag, not the Johnson R from APM, for example.