Gamma-ray Burst 190630C

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 30 Jun 19 23:53:24 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     912239,   Seg_Num: 0
GRB_RA:          293.908d {+19h 35m 38s} (J2000),
                 294.222d {+19h 36m 53s} (current),
                 293.103d {+19h 32m 25s} (1950)
GRB_DEC:         -32.751d {-32d 45' 03"} (J2000),
                 -32.707d {-32d 42' 24"} (current),
                 -32.862d {-32d 51' 43"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       3049 [cnts]    Image_Peak=182 [image_cnts]
TRIGGER_DUR:     1.024 [sec] 
TRIGGER_INDEX:   146     E_range: 25-100 keV
BKG_INTEN:       17465 [cnts]
BKG_TIME:        85960.83 SOD {23:52:40.83} UT
BKG_DUR:         8 [sec]
GRB_DATE:        18664 TJD;   181 DOY;   19/06/30
GRB_TIME:        85979.52 SOD {23:52:59.52} UT
GRB_PHI:         136.09 [deg]
GRB_THETA:        23.19 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     16.09 [sigma]
IMAGE_SIGNIF:    9.75 [sigma]
MERIT_PARAMS:     +1  +0  +0  +0  +2  +0  +0  +0 +96  +0 
SUN_POSTN:        99.69d {+06h 38m 46s}  +23.14d {+23d 08' 14"}
SUN_DIST:        164.01 [deg]   Sun_angle= 11.0 [hr] (West of Sun)
MOON_POSTN:       74.16d {+04h 56m 37s}  +19.77d {+19d 46' 23"}
MOON_DIST:       142.07 [deg]
MOON_ILLUM:      4 [%]
GAL_COORDS:        6.63,-22.96 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      290.32,-10.98 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT-BAT GRB Coordinates.  
COMMENTS:        This is a rate trigger.  
COMMENTS:        A point_source was found.  
COMMENTS:        This does not match any source in the on-board catalog.  
COMMENTS:        This does not match any source in the ground catalog.  
COMMENTS:        This is a GRB.  
COMMENTS:        This trigger occurred at longitude,latitude = 66.52,4.33 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 30 Jun 19 23:56:09 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     912239,   Seg_Num: 0
GRB_RA:          293.8789d {+19h 35m 30.9s} (J2000),
                 294.1924d {+19h 36m 46.1s} (current),
                 293.0738d {+19h 32m 17.7s} (1950)
GRB_DEC:         -32.7432d {-32d 44' 35.5"} (J2000),
                 -32.6990d {-32d 41' 56.3"} (current),
                 -32.8541d {-32d 51' 14.7"} (1950)
GRB_ERROR:       5.4 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       50 [cnts]
IMG_START_DATE:  18664 TJD;   181 DOY;   19/06/30
IMG_START_TIME:  86128.84 SOD {23:55:28.84} UT,   149.3 [sec] since BAT Trigger Time
CENTROID_X:      316.95,  raw= 317  [pixels]
CENTROID_Y:      381.79,  raw= 382  [pixels]
ROLL:            123.95 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   197.30
GRB_POS_XRT_Z:   22.53
IMAGE_URL:       sw00912239000msxps_rw.img
SUN_POSTN:        99.69d {+06h 38m 46s}  +23.14d {+23d 08' 13"}
SUN_DIST:        164.04 [deg]   Sun_angle= 11.0 [hr] (West of Sun)
MOON_POSTN:       74.18d {+04h 56m 44s}  +19.78d {+19d 46' 41"}
MOON_DIST:       142.12 [deg]
MOON_ILLUM:      4 [%]
GAL_COORDS:        6.63,-22.94 [deg] galactic lon,lat of the burst
ECL_COORDS:      290.29,-10.97 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 30 Jun 19 23:56:11 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     912239,   Seg_Num: 0
GRB_RA:          293.8789d {+19h 35m 30.9s} (J2000),
                 294.1924d {+19h 36m 46.1s} (current),
                 293.0738d {+19h 32m 17.7s} (1950)
GRB_DEC:         -32.7432d {-32d 44' 35.5"} (J2000),
                 -32.6990d {-32d 41' 56.3"} (current),
                 -32.8541d {-32d 51' 14.7"} (1950)
GRB_ERROR:       5.4 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       50 [cnts]
IMG_START_DATE:  18664 TJD;   181 DOY;   19/06/30
IMG_START_TIME:  86128.84 SOD {23:55:28.84} UT,   149.3 [sec] since BAT Trigger Time
CENTROID_X:      316.95,  raw= 317  [pixels]
CENTROID_Y:      381.79,  raw= 382  [pixels]
ROLL:            123.95 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   197.30
GRB_POS_XRT_Z:   22.53
IMAGE_URL:       sw00912239000msxps_rw.img
SUN_POSTN:        99.69d {+06h 38m 46s}  +23.14d {+23d 08' 13"}
SUN_DIST:        164.04 [deg]   Sun_angle= 11.0 [hr] (West of Sun)
MOON_POSTN:       74.18d {+04h 56m 44s}  +19.78d {+19d 46' 41"}
MOON_DIST:       142.12 [deg]
MOON_ILLUM:      4 [%]
GAL_COORDS:        6.63,-22.94 [deg] galactic lon,lat of the burst
ECL_COORDS:      290.29,-10.97 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 30 Jun 19 23:55:57 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     912239,   Seg_Num: 0
GRB_RA:          293.8789d {+19h 35m 30.93s} (J2000),
                 294.1924d {+19h 36m 46.17s} (current),
                 293.0738d {+19h 32m 17.71s} (1950)
GRB_DEC:         -32.7432d {-32d 44' 35.5"} (J2000),
                 -32.6990d {-32d 41' 56.3"} (current),
                 -32.8541d {-32d 51' 14.7"} (1950)
GRB_ERROR:       5.6 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.02e-09 [erg/cm2/sec]
GRB_SIGNIF:      7.07 [sigma]
IMG_START_DATE:  18664 TJD;   181 DOY;   19/06/30
IMG_START_TIME:  86128.84 SOD {23:55:28.84} UT,   149.3 [sec] since BAT Trigger Time
TAM[0-3]:        327.65 237.13 261.64 243.71
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:        99.69d {+06h 38m 46s}  +23.14d {+23d 08' 13"}
SUN_DIST:        164.04 [deg]   Sun_angle= 11.0 [hr] (West of Sun)
MOON_POSTN:       74.18d {+04h 56m 44s}  +19.78d {+19d 46' 40"}
MOON_DIST:       142.12 [deg]
MOON_ILLUM:      4 [%]
GAL_COORDS:        6.63,-22.94 [deg] galactic lon,lat of the burst
ECL_COORDS:      290.29,-10.97 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 1.55 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 30 Jun 19 23:57:06 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     912239,   Seg_Num: 0
GRB_RA:          293.908d {+19h 35m 38s} (J2000),
                 294.222d {+19h 36m 53s} (current),
                 293.103d {+19h 32m 25s} (1950)
GRB_DEC:         -32.751d {-32d 45' 03"} (J2000),
                 -32.707d {-32d 42' 24"} (current),
                 -32.862d {-32d 51' 43"} (1950)
GRB_DATE:        18664 TJD;   181 DOY;   19/06/30
GRB_TIME:        85979.52 SOD {23:52:59.52} UT
TRIGGER_INDEX:   146
GRB_PHI:         136.09 [deg]
GRB_THETA:        23.19 [deg]
DELTA_TIME:      52.00 [sec]
TRIGGER_DUR:     1.024 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     16.09 [sigma]
IMAGE_SIGNIF:    9.75 [sigma]
LC_URL:          sw00912239000msb.lc
SUN_POSTN:        99.69d {+06h 38m 46s}  +23.14d {+23d 08' 13"}
SUN_DIST:        164.02 [deg]   Sun_angle= 11.0 [hr] (West of Sun)
MOON_POSTN:       74.19d {+04h 56m 46s}  +19.78d {+19d 46' 47"}
MOON_DIST:       142.11 [deg]
MOON_ILLUM:      4 [%]
GAL_COORDS:        6.63,-22.96 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      290.32,-10.98 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT-BAT GRB Lightcurve.  
COMMENTS:           
COMMENTS:        The next comments were copied from the BAT_POS Notice:  
COMMENTS:        This is a rate trigger.  
COMMENTS:        A point_source was found.  
COMMENTS:        This does not match any source in the on-board catalog.  
COMMENTS:        This does not match any source in the ground catalog.  
COMMENTS:        This is a GRB.  
COMMENTS:        This trigger occurred at longitude,latitude = 66.52,4.33 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 30 Jun 19 23:58:35 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     912239,   Seg_Num: 0
POINT_RA:        293.850d {+19h 35m 24s} (J2000)
POINT_DEC:       -32.792d {-32d 47' 31"} (J2000)
POINT_ROLL:      123.949d
IMG_START_DATE:  18664 TJD;   181 DOY;   19/06/30
IMG_START_TIME:  86136.93 SOD {23:55:36.93} UT,   157.4 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        3.001
N_STARS:         190
X_OFFSET:        376 [pixels]
Y_OFFSET:        96 [pixels]
X_MAX:           1335 [pixels]
Y_MAX:           1055 [pixels]
DET_THRESH:      14
PHOTO_THRESH:    8
SL_URL:          sw00912239000msufc0157.fits
SUN_POSTN:        99.69d {+06h 38m 46s}  +23.14d {+23d 08' 13"}
SUN_DIST:        164.04 [deg]   Sun_angle= 11.0 [hr] (West of Sun)
MOON_POSTN:       74.21d {+04h 56m 50s}  +19.78d {+19d 46' 56"}
MOON_DIST:       142.16 [deg]
MOON_ILLUM:      4 [%]
GAL_COORDS:        6.57,-22.93 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      290.26,-11.02 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sun 30 Jun 19 23:58:59 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     912239,   Seg_Num: 0
POINT_RA:        293.850d {+19h 35m 24s} (J2000)
POINT_DEC:       -32.792d {-32d 47' 31"} (J2000)
POINT_ROLL:      123.949d
IMG_START_DATE:  18664 TJD;   181 DOY;   19/06/30
IMG_START_TIME:  86136.93 SOD {23:55:36.93} UT,   157.4 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        3.001
N_STARS:         190
X_OFFSET:        376 [pixels]
Y_OFFSET:        96 [pixels]
X_MAX:           1335 [pixels]
Y_MAX:           1055 [pixels]
DET_THRESH:      14
PHOTO_THRESH:    8
SL_URL:          sw00912239000msufc0157.fits
SUN_POSTN:        99.69d {+06h 38m 46s}  +23.14d {+23d 08' 13"}
SUN_DIST:        164.04 [deg]   Sun_angle= 11.0 [hr] (West of Sun)
MOON_POSTN:       74.21d {+04h 56m 51s}  +19.78d {+19d 46' 59"}
MOON_DIST:       142.17 [deg]
MOON_ILLUM:      4 [%]
GAL_COORDS:        6.57,-22.93 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      290.26,-11.02 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        All 4 attachments are included.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 01 Jul 19 00:01:16 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     912239,   Seg_Num: 0
POINT_RA:        293.850d {+19h 35m 24s} (J2000)
POINT_DEC:       -32.792d {-32d 47' 31"} (J2000)
ROLL:            123.949d
IMG_START_DATE:  18664 TJD;   181 DOY;   19/06/30
IMG_START_TIME:  86136.93 SOD {23:55:36.93} UT,   157.4 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     583631760
X_OFFSET:        569 [pixels]
Y_OFFSET:        548 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       729
Y_GRB_POS:       708
BINNING_INDEX:   1
IM_URL:          sw00912239000msuni0181.fits
SUN_POSTN:        99.70d {+06h 38m 47s}  +23.14d {+23d 08' 12"}
SUN_DIST:        164.04 [deg]   Sun_angle= 11.0 [hr] (West of Sun)
MOON_POSTN:       74.24d {+04h 56m 56s}  +19.79d {+19d 47' 13"}
MOON_DIST:       142.19 [deg]
MOON_ILLUM:      4 [%]
GAL_COORDS:        6.57,-22.93 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      290.26,-11.02 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Image.  
COMMENTS:        The GRB Position came from the XRT Position Command.  
COMMENTS:        The image has 2x2 binning (compression).

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 01 Jul 19 00:01:31 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     912239,   Seg_Num: 0
POINT_RA:        293.850d {+19h 35m 24s} (J2000)
POINT_DEC:       -32.792d {-32d 47' 31"} (J2000)
ROLL:            123.949d
IMG_START_DATE:  18664 TJD;   181 DOY;   19/06/30
IMG_START_TIME:  86136.93 SOD {23:55:36.93} UT,   157.4 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     583631760
X_OFFSET:        569 [pixels]
Y_OFFSET:        548 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       729
Y_GRB_POS:       708
BINNING_INDEX:   1
IM_URL:          sw00912239000msuni0181.fits
SUN_POSTN:        99.70d {+06h 38m 47s}  +23.14d {+23d 08' 12"}
SUN_DIST:        164.04 [deg]   Sun_angle= 11.0 [hr] (West of Sun)
MOON_POSTN:       74.24d {+04h 56m 57s}  +19.79d {+19d 47' 15"}
MOON_DIST:       142.19 [deg]
MOON_ILLUM:      4 [%]
GAL_COORDS:        6.57,-22.93 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      290.26,-11.02 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Image.  
COMMENTS:        The GRB Position came from the XRT Position Command.  
COMMENTS:        The image has 2x2 binning (compression).  
COMMENTS:        All 4 attachments are included.

GCN Circular #24927
T. N. Ukwatta (LANL), J.D. Gropp (PSU), H. A. Krimm (NSF), F. E. Marshall (NASA/GSFC), K. L. Page (U Leicester), D. M. Palmer (LANL) and A. Tohuvavohu (PSU) report on behalf of the Neil Gehrels Swift Observatory Team:
At 23:52:59 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 190630C (trigger=912239). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 293.908, -32.751 which is
```
   RA(J2000) = 19h 35m 38s
   Dec(J2000) = -32d 45' 03"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a single-peaked structure with a duration of about 120 sec. The peak count rate was ~2000 counts/sec (15-350 keV), at ~0 sec after the trigger.
The XRT began observing the field at 23:55:28.8 UT, 149.3 seconds after the BAT trigger. Using promptly downlinked data we find a bright, fading, uncatalogued X-ray source located at RA, Dec 293.87874, -32.74273 which is equivalent to:
```
   RA(J2000)  = 19h 35m 30.90s
   Dec(J2000) = -32d 44' 33.8"
```
with an uncertainty of 3.8 arcseconds (radius, 90% containment). This location is 93 arcseconds from the BAT onboard position, within the BAT error circle. This position may be improved as more data are received; the latest position is available at http://www.swift.ac.uk/sper. No spectrum from the promptly downlinked event data is yet available to determine the column density.
The initial flux in the 2.5 s image was 1.02e-09 erg cm^-2 s^-1 (0.2-10 keV). UVOT took a finding chart exposure of 150 seconds with the White filter starting 157 seconds after the BAT trigger. No credible afterglow candidate has been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of the XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. The 8'x8' region for the list of sources generated on-board covers 100% of the XRT error circle. The list of sources is typically complete to about 18 mag. No correction has been made for the expected extinction corresponding to E(B-V) of 0.11.
This source lies within the current (Sector 13) field-of-view of TESS camera 1.
Burst Advocate for this burst is T. N. Ukwatta (tilan.ukwatta AT gmail.com). Please contact the BA by email if you require additional information regarding Swift followup of this burst. In extremely urgent cases, after trying the Burst Advocate, you can contact the Swift PI by phone (see Swift TOO web site for information: http://www.swift.psu.edu/)
GCN Circular #24929
V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, F.Balakin, V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva, D.Kuvshinov (Lomonosov Moscow State University, SAI, Physics Department),
R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar OAFA),
H.Levato (Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE),
R. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias)
D. Buckley (South African Astronomical Observatory),
O.A. Gres, N.M. Budnev, O.Ershova (Irkutsk State University, API),
A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),
V. Yurkov, A. Gabovich, Yu. Sergienko (Blagoveschensk Educational State University)
MASTER-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) was pointed to the Swift GRB190631. (trigger No 912239, 19h 35m 37.92s , -32d 45m 03.60s, R=0.05) errorbox 50 sec after trigger time at 2019-06-30 23:53:49 UT, with upper limit up to 17.8 mag. Observations started at twilight. The observations began at zenit distance = 78 deg. The sun altitude is -16.8 deg.
MASTER-OAFA robotic telescope located in Argentina (OAFA observatory of San Juan National University) was pointed to the Swift GRB190631. errorbox 56 sec after trigger time at 2019-06-30 23:53:55 UT, with upper limit up to 17.6 mag. The observations began at zenit distance = 71 deg. The sun altitude is -27.2 deg.
MASTER-IAC robotic telescope located in Spain (IAC Teide Observatory) was pointed to the Swift GRB190631. errorbox 83 sec after trigger time at 2019-06-30 23:54:22 UT, with upper limit up to 18.8 mag. The observations began at zenit distance = 68 deg. The sun altitude is -36.0 deg.
The galactic latitude b = -60 deg., longitude l = 98 deg.
Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1061706
We obtain a following upper limits.
```
Tmid-T0  |          Site       |Filt.| Expt. | Limit| Comment
_________|_____________________|_____|_______|______|________

      55 |      MASTER-Tavrida |   C |    10 | 16.5 | 
      61 |         MASTER-OAFA |   C |    10 | 16.5 | 
      94 |          MASTER-IAC |  P| |    20 | 17.5 |
      94 |          MASTER-IAC |  P- |    20 | 17.2 |
      94 |      MASTER-Tavrida |   C |    20 | 17.2 | 
     117 |         MASTER-OAFA |   C |    20 | 17.0 |
     143 |      MASTER-Tavrida |   C |    30 | 17.4 |
     150 |          MASTER-IAC |  P| |    30 | 17.8 |
     150 |          MASTER-IAC |  P- |    30 | 17.5 |
     184 |         MASTER-OAFA |   C |    30 | 17.2 |
     202 |      MASTER-Tavrida |   C |    40 | 17.6 |
     204 |          MASTER-IAC |  P- |    40 | 17.6 |
     204 |          MASTER-IAC |  P| |    40 | 18.1 |
     267 |         MASTER-OAFA |   C |    50 | 17.5 |
     269 |          MASTER-IAC |  P| |    50 | 18.3 | 
     269 |          MASTER-IAC |  P- |    50 | 17.9 | 
     271 |      MASTER-Tavrida |   C |    50 | 17.8 |
     343 |          MASTER-IAC |  P| |    60 | 18.5 |
     343 |          MASTER-IAC |  P- |    60 | 18.1 |
     368 |         MASTER-OAFA |   C |    70 | 17.6 |
     434 |          MASTER-IAC |  P- |    80 | 18.3 |
     435 |          MASTER-IAC |  P| |    80 | 18.7 |
     544 |          MASTER-IAC |  P- |   100 | 18.5 |
     544 |          MASTER-IAC |  P| |   100 | 18.8 |
```
Filter C is a clear (unfiltred) band.
The observation and reduction will continue. The message may be cited.
GCN Circular #24930
M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team.
Using 195 s of XRT Photon Counting mode data and 1 UVOT images for GRB 190630C, we find an astrometrically corrected X-ray position (using the XRT-UVOT alignment and matching UVOT field sources to the USNO-B1 catalogue): RA, Dec = 293.88034, -32.74405 which is equivalent to:
```
RA (J2000): 19h 35m 31.28s
Dec (J2000): -32d 44' 38.6"
```
with an uncertainty of 1.9 arcsec (radius, 90% confidence).
This position may be improved as more data are received. The latest position can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans et al. (2009, MNRAS, 397, 1177).
This circular was automatically generated, and is an official product of the Swift-XRT team.
GCN Circular #24939
V. Sharma, R. Gaikwad, D. Bhattacharya and A. Vibhute (IUCAA), V. Bhalerao (IIT-B), A. R. Rao (TIFR) and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:
Analysis of AstroSat CZTI data showed the detection of a long GRB 190630C, which +was also detected by Swift (Ukwatta T. N. et al., GCN # 24927) and Swift-XRT (Goad M. R. et al., GCN # 24930).
The source was clearly detected in the 40-200 keV energy range. The light curve shows single pulse of emission with strongest peak at 23:53:01 UT. The measured peak count rate associated with the burst is 153 cts/s above the background in the combined data of four quadrants, with a total of 1301 cts. The local mean background count rate was 571 cts/s. Using cumulative rates, we measure a T90 of 21.3 s.
It was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range.
CZTI GRB detections are reported regularly on the payload site at http://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC and PRL. The Indian Space Research Organisation funded, managed and facilitated the project.
GCN Circular #24941
H. A. Krimm (NSF), S. D. Barthelmy (GSFC), J. R. Cummings (CPI), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):
Using the data set from T-240 to T+962 sec from the recent telemetry downlink, we report further analysis of BAT GRB 190630C (trigger #912239) (Ukwatta, et al., GCN Circ. 24927). The BAT ground-calculated position is RA, Dec = 293.890, -32.759 deg which is
```
  RA(J2000)  =  19h 35m 33.6s
  Dec(J2000) = -32d 45' 32.5"
```
with an uncertainty of 1.1 arcmin, (radius, sys+stat, 90% containment). The partial coding was 57%.
The mask-weighted light curve shows a single FRED-shaped burst, beginning at ~T-5 sec, peaking at T+0 sec, and declining to background by ~T+40 sec. A spacecraft slew took the burst position out of the BAT field of view just before T+500 sec. T90 (15-350 keV) is 38.4 +- 9.3 sec (estimated error including systematics).
The time-averaged spectrum from T-1.92 to T+50.23 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.96 +- 0.11. The fluence in the 15-150 keV band is 2.3 +- 0.2 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T-0.12 sec in the 15-150 keV band is 2.0 +- 0.3 ph/cm2/sec. All the quoted errors are at the 90% confidence level.
The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/912239/BA/
GCN Circular #24944
WeiKang Zheng and Alexei V. Filippenko (UC Berkeley) report on behalf of the KAIT GRB team:
The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at Lick Observatory, responded to Swift GRB 190630C (Ukwatta et al., GCN 24927) starting at ~0.379 days after the burst. Observations were performed in the clear (roughly R) filters, a total of 31 images were obtained and the exposure time was 60 s per image. We do not detect any optical afterglow candidate within the Enhanced XRT position error circle (Goad et al., GCN 24930), neither in single image, nor in the co-add images. We estimate our limiting magnitude of our co-added image is ~19.0 mag calibrated to the APASS catalog.
GCN Circular #24945
GRB 190630C: Swift/UVOT Upper Limits
K. K. Simpson (PSU) and T. N. Ukwatta (LANL) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 190630C 136 s after the BAT trigger (Ukwatta et al., GCN Circ. 24927). No optical afterglow consistent with the XRT position (Goad et al. GCN Circ. 24930) is detected in the initial UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first finding chart (FC) exposure and subsequent exposures are:
```
Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white_FC           157          307          147         >20.5
white              157          307          147         >20.5
v                  136          412           32         >18.1
w2                 367          387           19         >20.1
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.11 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #24947
S. Belkin (IKI), S. Schmalz (KIAM), A. Pozanenko (IKI), A. Volnova (IKI), E. Mazaeva (IKI), I. Molotov (KIAM) report on behalf of larger GRB IKI FuN collaboration:
We observed the field of GRB 190630C (Ukwatta et al., GCN 24927) with ORI-22 (22 cm) telescope of ISON-Castelgrande observatory in Clear filter starting on July 01 (UT) 00:03:42. We do not detect any object within enhanced Swift-XRT position (Goad et al., GCN 24930). Preliminary photometry of the field is following
```
  
Date       UT start t-T0    Filter Exp.   OT    Err. UL  
                     (mid, days) (s)
  
2019-07-01 00:03:42 0.02584  CR    53*60  n/d   n/d 18.8
```
The photometry is based on nearby USNO-B1.0 (R2) stars.
GCN Circular #24958
M.G. Bernardini (INAF-OAB), E. Ambrosi (INAF-IASFPA) , V. D'Elia (ASDC), B. Sbarufatti (PSU), D.N. Burrows (PSU), J. D. Gropp (PSU), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester) and T.N. Ukwatta report on behalf of the Swift-XRT team:
We have analysed 5.7 ks of XRT data for GRB 190630C (Ukwatta et al. GCN Circ. 24927), from 155 s to 57.3 ks after the BAT trigger. The data comprise 56 s in Windowed Timing (WT) mode with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Goad et al. (GCN Circ. 24930).
The light curve can be modelled with an initial power-law decay with an index of alpha=4.3 (+0.7, -0.5), followed by a break at T+310 s to an alpha of 1.06 (+0.12, -0.23).
A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 3.09 (+0.33, -0.29). The best-fitting absorption column is 2.7 (+/-0.7) x 10^21 cm^-2, in excess of the Galactic value of 1.1 x 10^21 cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index of 2.2 (+/-0.3) and a best-fitting absorption column of 2.0 (+1.0, -0.9) x 10^21 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.2 x 10^-11 (4.8 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:        2.0 (+1.0, -0.9) x 10^21 cm^-2
Galactic foreground: 1.1 x 10^21 cm^-2
Excess significance: 1.7 sigma 
Photon index:        2.2 (+/-0.3) 
```
If the light curve continues to decay with a power-law decay index of 1.06, the count rate at T+24 hours will be 3.0 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 9.7 x 10^-14 (1.4 x 10^-13) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00912239.
This circular is an official product of the Swift-XRT team.

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Jochen Greiner, last update: 01-Jul-2019 [Disclaimer]