Gamma-ray Burst 181030A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

• none

• GCN/BACODINE POSITION NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Tue 30 Oct 18 01:28:41 UT
  NOTICE_TYPE:     Swift-BAT GRB Position
  TRIGGER_NUM:     869494,   Seg_Num: 0
  GRB_RA:          146.922d {+09h 47m 41s} (J2000),
                   147.178d {+09h 48m 43s} (current),
                   146.241d {+09h 44m 58s} (1950)
  GRB_DEC:         +14.658d {+14d 39' 28"} (J2000),
                   +14.570d {+14d 34' 12"} (current),
                   +14.890d {+14d 53' 25"} (1950)
  GRB_ERROR:       3.00 [arcmin radius, statistical only]
  GRB_INTEN:       0 [cnts]    Image_Peak=3135 [image_cnts]
  TRIGGER_DUR:     64.000 [sec] 
  TRIGGER_INDEX:   20000     E_range: 15-50 keV
  BKG_INTEN:       0 [cnts]
  BKG_TIME:        0.00 SOD {00:00:00.00} UT
  BKG_DUR:         0 [sec]
  GRB_DATE:        18421 TJD;   303 DOY;   18/10/30
  GRB_TIME:        5242.16 SOD {01:27:22.16} UT
  GRB_PHI:          -6.49 [deg]
  GRB_THETA:        35.76 [deg]
  SOLN_STATUS:     0x13
  RATE_SIGNIF:     0.00 [sigma]
  IMAGE_SIGNIF:    17.58 [sigma]
  MERIT_PARAMS:     +1  +0  +0  +6  +1  +5  +0  +0 -30  +0 
  SUN_POSTN:       214.25d {+14h 16m 59s}  -13.71d {-13d 42' 33"}
  SUN_DIST:         72.14 [deg]   Sun_angle= 4.5 [hr] (West of Sun)
  MOON_POSTN:      106.27d {+07h 05m 06s}  +21.20d {+21d 11' 52"}
  MOON_DIST:        39.38 [deg]
  MOON_ILLUM:      68 [%]
  GAL_COORDS:      219.63, 45.58 [deg] galactic lon,lat of the burst (or transient)
  ECL_COORDS:      144.18,  1.27 [deg] ecliptic lon,lat of the burst (or transient)
  COMMENTS:        SWIFT-BAT GRB Coordinates.  
  COMMENTS:        This is an image trigger.  (The RATE_SIGNIF & BKG_{INTEN, TIME, DUR} are undefined.)  
  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 = 157.18,-7.51 [deg].  
  

• red DSS finding chart ps-file
  
  
• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Tue 30 Oct 18 01:30:20 UT
  NOTICE_TYPE:     Swift-XRT Image
  TRIGGER_NUM:     869494,   Seg_Num: 0
  GRB_RA:          146.9251d {+09h 47m 42.0s} (J2000),
                   147.1812d {+09h 48m 43.4s} (current),
                   146.2441d {+09h 44m 58.5s} (1950)
  GRB_DEC:         +14.6582d {+14d 39' 29.5"} (J2000),
                   +14.5702d {+14d 34' 12.8"} (current),
                   +14.8906d {+14d 53' 26.1"} (1950)
  GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
  GRB_INTEN:       135 [cnts]
  IMG_START_DATE:  18421 TJD;   303 DOY;   18/10/30
  IMG_START_TIME:  5384.25 SOD {01:29:44.25} UT,   142.1 [sec] since BAT Trigger Time
  CENTROID_X:      334.95,  raw= 335  [pixels]
  CENTROID_Y:      304.21,  raw= 304  [pixels]
  ROLL:            109.86 [deg]
  GAIN:            2
  MODE:            3, Long Image mode
  WAVEFORM:        134
  EXPO_TIME:       2.50 [sec]
  GRB_POS_XRT_Y:   13.69
  GRB_POS_XRT_Z:   67.31
  IMAGE_URL:       sw00869494000msxps_rw.img
  SUN_POSTN:       214.25d {+14h 16m 59s}  -13.71d {-13d 42' 34"}
  SUN_DIST:         72.13 [deg]   Sun_angle= 4.5 [hr] (West of Sun)
  MOON_POSTN:      106.29d {+07h 05m 10s}  +21.20d {+21d 11' 50"}
  MOON_DIST:        39.36 [deg]
  MOON_ILLUM:      68 [%]
  GAL_COORDS:      219.63, 45.58 [deg] galactic lon,lat of the burst
  ECL_COORDS:      144.18,  1.27 [deg] ecliptic lon,lat of the burst
  COMMENTS:        SWIFT-XRT Image.  
  COMMENTS:        The object found at this position is either a very bright burst or a cosmic ray hit.  
  COMMENTS:        Examine the XRT Image to differentiate (CRs are much more compact); see examples at: 
  COMMENTS:        http://www.swift.psu.edu/xrt/XRT_Postage_Stamp_Image_Photo_Gallery.htm .  
  

• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Tue 30 Oct 18 01:30:10 UT
  NOTICE_TYPE:     Swift-XRT Position
  TRIGGER_NUM:     869494,   Seg_Num: 0
  GRB_RA:          146.9251d {+09h 47m 42.02s} (J2000),
                   147.1812d {+09h 48m 43.48s} (current),
                   146.2441d {+09h 44m 58.59s} (1950)
  GRB_DEC:         +14.6582d {+14d 39' 29.5"} (J2000),
                   +14.5702d {+14d 34' 12.8"} (current),
                   +14.8906d {+14d 53' 26.1"} (1950)
  GRB_ERROR:       4.8 [arcsec radius, statistical plus systematic, 90% containment]
  GRB_INTEN:       5.25e-09 [erg/cm2/sec]
  GRB_SIGNIF:      11.61 [sigma]
  IMG_START_DATE:  18421 TJD;   303 DOY;   18/10/30
  IMG_START_TIME:  5384.25 SOD {01:29:44.25} UT,   142.1 [sec] since BAT Trigger Time
  TAM[0-3]:        327.65 237.20 261.63 243.30
  AMPLIFIER:       2
  WAVEFORM:        134
  SUN_POSTN:       214.25d {+14h 16m 59s}  -13.71d {-13d 42' 34"}
  SUN_DIST:         72.13 [deg]   Sun_angle= 4.5 [hr] (West of Sun)
  MOON_POSTN:      106.29d {+07h 05m 10s}  +21.20d {+21d 11' 51"}
  MOON_DIST:        39.37 [deg]
  MOON_ILLUM:      68 [%]
  GAL_COORDS:      219.63, 45.58 [deg] galactic lon,lat of the burst
  ECL_COORDS:      144.18,  1.27 [deg] ecliptic lon,lat of the burst
  COMMENTS:        SWIFT-XRT Coordinates.  
  COMMENTS:        The XRT position is 0.17 arcmin from the BAT position.  
  COMMENTS:        The object found at this position is either a very bright burst or a cosmic ray hit.  
  COMMENTS:        Examine the XRT Image to differentiate (CRs are much more compact); see examples at:  
  COMMENTS:        http://www.swift.psu.edu/xrt/XRT_Postage_Stamp_Image_Photo_Gallery.htm .  
  

• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Tue 30 Oct 18 01:30:22 UT
  NOTICE_TYPE:     Swift-XRT Processed Image
  TRIGGER_NUM:     869494,   Seg_Num: 0
  GRB_RA:          146.9251d {+09h 47m 42.0s} (J2000),
                   147.1812d {+09h 48m 43.4s} (current),
                   146.2441d {+09h 44m 58.5s} (1950)
  GRB_DEC:         +14.6582d {+14d 39' 29.5"} (J2000),
                   +14.5702d {+14d 34' 12.8"} (current),
                   +14.8906d {+14d 53' 26.1"} (1950)
  GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
  GRB_INTEN:       135 [cnts]
  IMG_START_DATE:  18421 TJD;   303 DOY;   18/10/30
  IMG_START_TIME:  5384.25 SOD {01:29:44.25} UT,   142.1 [sec] since BAT Trigger Time
  CENTROID_X:      334.95,  raw= 335  [pixels]
  CENTROID_Y:      304.21,  raw= 304  [pixels]
  ROLL:            109.86 [deg]
  GAIN:            2
  MODE:            3, Long Image mode
  WAVEFORM:        134
  EXPO_TIME:       2.50 [sec]
  GRB_POS_XRT_Y:   13.69
  GRB_POS_XRT_Z:   67.31
  IMAGE_URL:       sw00869494000msxps_rw.img
  SUN_POSTN:       214.25d {+14h 16m 59s}  -13.71d {-13d 42' 34"}
  SUN_DIST:         72.13 [deg]   Sun_angle= 4.5 [hr] (West of Sun)
  MOON_POSTN:      106.29d {+07h 05m 10s}  +21.20d {+21d 11' 50"}
  MOON_DIST:        39.36 [deg]
  MOON_ILLUM:      68 [%]
  GAL_COORDS:      219.63, 45.58 [deg] galactic lon,lat of the burst
  ECL_COORDS:      144.18,  1.27 [deg] ecliptic lon,lat of the burst
  COMMENTS:        SWIFT-XRT Processed Image.  
  COMMENTS:        The object found at this position is either a very bright burst or a cosmic ray hit.  
  COMMENTS:        Examine the XRT Image to differentiate (CRs are much more compact); see examples at:  
  COMMENTS:        http://www.swift.psu.edu/xrt/XRT_Postage_Stamp_Image_Photo_Gallery.htm .  
  

  
• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Tue 30 Oct 18 01:31:14 UT
  NOTICE_TYPE:     Swift-BAT GRB Lightcurve
  TRIGGER_NUM:     869494,   Seg_Num: 0
  GRB_RA:          146.922d {+09h 47m 41s} (J2000),
                   147.178d {+09h 48m 43s} (current),
                   146.241d {+09h 44m 58s} (1950)
  GRB_DEC:         +14.658d {+14d 39' 28"} (J2000),
                   +14.570d {+14d 34' 12"} (current),
                   +14.890d {+14d 53' 25"} (1950)
  GRB_DATE:        18421 TJD;   303 DOY;   18/10/30
  GRB_TIME:        5242.16 SOD {01:27:22.16} UT
  TRIGGER_INDEX:   20000
  GRB_PHI:          -6.49 [deg]
  GRB_THETA:        35.76 [deg]
  DELTA_TIME:      0.00 [sec]
  TRIGGER_DUR:     64.000 [sec] 
  SOLN_STATUS:     0x13
  RATE_SIGNIF:     0.00 [sigma]
  IMAGE_SIGNIF:    17.58 [sigma]
  LC_URL:          sw00869494000msb.lc
  SUN_POSTN:       214.25d {+14h 16m 59s}  -13.71d {-13d 42' 35"}
  SUN_DIST:         72.14 [deg]   Sun_angle= 4.5 [hr] (West of Sun)
  MOON_POSTN:      106.30d {+07h 05m 12s}  +21.20d {+21d 11' 50"}
  MOON_DIST:        39.35 [deg]
  MOON_ILLUM:      68 [%]
  GAL_COORDS:      219.63, 45.58 [deg] galactic lon,lat of the burst (or transient)
  ECL_COORDS:      144.18,  1.27 [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 an image 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 = 157.18,-7.51 [deg].  
  

  
• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Tue 30 Oct 18 01:36:40 UT
  NOTICE_TYPE:     Swift-UVOT Source List
  TRIGGER_NUM:     869494,   Seg_Num: 0
  POINT_RA:        146.942d {+09h 47m 46s} (J2000)
  POINT_DEC:       +14.649d {+14d 38' 55"} (J2000)
  POINT_ROLL:      109.854d
  IMG_START_DATE:  18421 TJD;   303 DOY;   18/10/30
  IMG_START_TIME:  5393.93 SOD {01:29:53.93} UT,   151.8 [sec] since BAT Trigger Time
  FILTER:          10, White
  BKG_MEAN:        1.392
  N_STARS:         190
  X_OFFSET:        344 [pixels]
  Y_OFFSET:        624 [pixels]
  X_MAX:           1303 [pixels]
  Y_MAX:           1583 [pixels]
  DET_THRESH:      10
  PHOTO_THRESH:    5
  SL_URL:          sw00869494000msufc0151.fits
  SUN_POSTN:       214.25d {+14h 17m 00s}  -13.71d {-13d 42' 39"}
  SUN_DIST:         72.12 [deg]   Sun_angle= 4.5 [hr] (West of Sun)
  MOON_POSTN:      106.36d {+07h 05m 26s}  +21.20d {+21d 11' 45"}
  MOON_DIST:        39.32 [deg]
  MOON_ILLUM:      68 [%]
  GAL_COORDS:      219.65, 45.59 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      144.20,  1.27 [deg] ecliptic lon,lat of the pointing direction
  COMMENTS:        SWIFT-UVOT Source List.  
  

• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Tue 30 Oct 18 01:36:51 UT
  NOTICE_TYPE:     Swift-UVOT Processed Source List
  TRIGGER_NUM:     869494,   Seg_Num: 0
  POINT_RA:        146.942d {+09h 47m 46s} (J2000)
  POINT_DEC:       +14.649d {+14d 38' 55"} (J2000)
  POINT_ROLL:      109.854d
  IMG_START_DATE:  18421 TJD;   303 DOY;   18/10/30
  IMG_START_TIME:  5393.93 SOD {01:29:53.93} UT,   151.8 [sec] since BAT Trigger Time
  FILTER:          10, White
  BKG_MEAN:        1.392
  N_STARS:         190
  X_OFFSET:        344 [pixels]
  Y_OFFSET:        624 [pixels]
  X_MAX:           1303 [pixels]
  Y_MAX:           1583 [pixels]
  DET_THRESH:      10
  PHOTO_THRESH:    5
  SL_URL:          sw00869494000msufc0151.fits
  SUN_POSTN:       214.25d {+14h 17m 00s}  -13.71d {-13d 42' 40"}
  SUN_DIST:         72.12 [deg]   Sun_angle= 4.5 [hr] (West of Sun)
  MOON_POSTN:      106.36d {+07h 05m 27s}  +21.20d {+21d 11' 45"}
  MOON_DIST:        39.32 [deg]
  MOON_ILLUM:      68 [%]
  GAL_COORDS:      219.65, 45.59 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      144.20,  1.27 [deg] ecliptic lon,lat of the pointing direction
  COMMENTS:        SWIFT-UVOT Processed Source List.  
  COMMENTS:        If you have elected to receive attachments:  
  COMMENTS:        The uvot_catalog_srclist.fits.gz file does not exist; skipping the attachment.  
  

  
• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Tue 30 Oct 18 01:39:06 UT
  NOTICE_TYPE:     Swift-UVOT Image
  TRIGGER_NUM:     869494,   Seg_Num: 0
  POINT_RA:        146.942d {+09h 47m 46s} (J2000)
  POINT_DEC:       +14.649d {+14d 38' 55"} (J2000)
  ROLL:            109.854d
  IMG_START_DATE:  18421 TJD;   303 DOY;   18/10/30
  IMG_START_TIME:  5393.93 SOD {01:29:53.93} UT,   151.8 [sec] since BAT Trigger Time
  FILTER:          10, White
  EXPOSURE_ID:     562555815
  X_OFFSET:        669 [pixels]
  Y_OFFSET:        929 [pixels]
  WIDTH:           160 [pixels]
  HEIGHT:          160 [pixels]
  X_GRB_POS:       829
  Y_GRB_POS:       1089
  BINNING_INDEX:   1
  IM_URL:          sw00869494000msuni0173.fits
  SUN_POSTN:       214.25d {+14h 17m 01s}  -13.71d {-13d 42' 41"}
  SUN_DIST:         72.12 [deg]   Sun_angle= 4.5 [hr] (West of Sun)
  MOON_POSTN:      106.38d {+07h 05m 32s}  +21.20d {+21d 11' 42"}
  MOON_DIST:        39.30 [deg]
  MOON_ILLUM:      68 [%]
  GAL_COORDS:      219.65, 45.59 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      144.20,  1.27 [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:     Tue 30 Oct 18 01:39:17 UT
  NOTICE_TYPE:     Swift-UVOT Processed Image
  TRIGGER_NUM:     869494,   Seg_Num: 0
  POINT_RA:        146.942d {+09h 47m 46s} (J2000)
  POINT_DEC:       +14.649d {+14d 38' 55"} (J2000)
  ROLL:            109.854d
  IMG_START_DATE:  18421 TJD;   303 DOY;   18/10/30
  IMG_START_TIME:  5393.93 SOD {01:29:53.93} UT,   151.8 [sec] since BAT Trigger Time
  FILTER:          10, White
  EXPOSURE_ID:     562555815
  X_OFFSET:        669 [pixels]
  Y_OFFSET:        929 [pixels]
  WIDTH:           160 [pixels]
  HEIGHT:          160 [pixels]
  X_GRB_POS:       829
  Y_GRB_POS:       1089
  BINNING_INDEX:   1
  IM_URL:          sw00869494000msuni0173.fits
  SUN_POSTN:       214.25d {+14h 17m 01s}  -13.71d {-13d 42' 42"}
  SUN_DIST:         72.12 [deg]   Sun_angle= 4.5 [hr] (West of Sun)
  MOON_POSTN:      106.39d {+07h 05m 33s}  +21.20d {+21d 11' 42"}
  MOON_DIST:        39.30 [deg]
  MOON_ILLUM:      68 [%]
  GAL_COORDS:      219.65, 45.59 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      144.20,  1.27 [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:        If you have elected to receive attachments:  
  COMMENTS:        The uvot_catalog_image.fits.gz file does not exist; skipping the attachment.  
  

  
• GCN Circular #23389
  E. Sonbas (Adiyaman Univ.), J.D. Gropp (PSU), J. A. Kennea (PSU), A. Y. Lien (GSFC/UMBC), M. J. Moss (George Washington University), K. L. Page (U Leicester), M. H. Siegel (PSU) and A. Tohuvavohu (PSU) report on behalf of the Neil Gehrels Swift Observatory Team:
  At 01:27:22 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 181030A (trigger=869494). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 146.922, +14.658 which is

     RA(J2000) = 09h 47m 41s
     Dec(J2000) = +14d 39' 28"
  

  with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). As is usual with an image trigger, the available BAT light curve shows no significant structure.
  The XRT began observing the field at 01:29:44.2 UT, 142.1 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 146.9251, 14.6582 which is equivalent to:

     RA(J2000)  = 09h 47m 42.02s
     Dec(J2000) = +14d 39' 29.5"
  

  with an uncertainty of 4.8 arcseconds (radius, 90% containment). This location is 10 arcseconds from the BAT onboard position, within the BAT error circle. No event data are yet available to determine the column density using X-ray spectroscopy.
  The initial flux in the 2.5 s image was 5.25e-09 erg cm^-2 s^-1 (0.2-10 keV).
  UVOT took a finding chart exposure of 118 seconds with the White filter starting 151 seconds after the BAT trigger. There is a possible afterglow in the rapidly available 2.7'x2.7' sub-image near the position of the XRT afterglow. A precise position is unavailable due to a failed aspect correction. The estimated magnitude is 18.94 with a 1-sigma error of about 0.22.
  Burst Advocate for this burst is E. Sonbas (edasonbas AT yahoo.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/too.html.)
• GCN Circular #23390
  A. S. Moskvitin and O. I. Spiridonova (SAO RAS) report on behalf of larger collaboration.
  We observed the field of GRB 181030A (Sonbas et al., GCNC #23389) with the Zeiss-1000 telescope of SAO RAS (+ CCD photometer) on the October, 30.
  The observations started since 10 minutes after the trigger (UT_start = 01:37:35, UT_end = 02:49:36). We obtained 12 x 300 sec. images in Rc band. We detect the OT discovered by the Swift/UVOT at the position (+/- 1"):

  R. A. (2000) =  09:47:42.3
  Decl. (2000) = +14:39:25.8
  

  The OT magnitude is R = 19.12 +/- 0.03 (UT_mid = 02:13:35).
  Calibrations were made against the nearby SDSS stars (magnitudes transformed to Rc according to the Lupton, 2005).
• GCN Circular #23391
  A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) report on behalf of the Swift-XRT team.
  Using 2439 s of XRT Photon Counting mode data and 6 UVOT images for GRB 181030A, 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 = 146.92603, +14.65731 which is equivalent to:

  RA (J2000): 09h 47m 42.25s
  Dec (J2000): +14d 39' 26.3"
  

  with an uncertainty of 1.7 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 #23392
  V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Vladimirov, D. Vlasenko Lomonosov Moscow State University, SAI, Physics Department
  A. Tlatov, V.Senik, D. Dormidontov Kislovodsk Solar Station of the Pulkovo Observatory
  D. Buckley, South African Astronomical Observatory
  R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres The Instituto de Astrofisica de Canarias
  O. Gres, N.M. Budnev, O.Ershova, Yu.Ishmuhametov Applied Physics Institute, Irkutsk State University
  V. Yurkov, A. Gabovich, Yu. Sergienko Blagoveschensk Educational State University, Blagoveschensk
  R. Podesta, Carlos Lopez, F. Podesta, C.Francile Observatorio Astronomico Felix Aguilar (OAFA)
  H. Levato Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)
  MASTER Global Robotic Net (http://observ.pereplet.ru , Lipunov et al. Advances in Astronomy, 2010, 30L http://adsabs.harvard.edu/abs/2010AdAst2010E..30L) started Swift GRB 181030A (Sonbas et al. GCN23389, Beardmore et al. GCN23391) optical alert observations 21 sec after notice time at 2018-10-30 01:29:03 UT
  MASTER-Kislovodsk robotic telescope, located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) was pointed to the GRB181030A 21 sec after notice time and 101 sec after trigger time at 2018-10-30 01:29:03 UT. On our first 20s expos. set , started at 2018-10-30 01:29:03 UT, we found optical transient within SWIFT error-box MASTER OT J094742.25+143925.73 (also detected by Sonbas et al SwiftUVOT GCN23389 and by Moskvitin et al. GCN 23390) with m_OT=16.5 and falling light curve in both polarization filters.
  The galactic latitude b = 46 deg., longitude l = 220 deg. The observations made on zenit distance = 47 deg. The moon (68 % bright part) was 67 deg. above the horizon.The distance between moon and object was 39 deg The sun altitude was -24.2 deg.
  MASTER-Tavrida robotic telescope located in Russia (Lomonosov MSU, SAI Crimea astronomical station) was pointed to the GRB181030A 31 sec after notice time and 105 sec after trigger time at 2018-10-30 01:29:13 UT. The observations started on zenit distance = 51 deg. The moon (68 % bright part) was 66 deg. above the horizon. The distance between moon and object was 39 The sun altitude was -27.9 deg.
• GCN Circular #23394
  P. D'Avanzo (INAF-OAB), S. J. LaPorte (PSU), J.A. Kennea (PSU), B. Sbarufatti (INAF-OAB/PSU), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), V. D'Elia (ASDC), A. D'Ai (INAF-IASFPA) and E. Sonbas report on behalf of the Swift-XRT team:
  We have analysed 7.2 ks of XRT data for GRB 181030A (Sonbas et al. GCN Circ. 23389), from 148 s to 32.8 ks after the BAT trigger. The data comprise 121 s in Windowed Timing (WT) mode with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Beardmore et al. (GCN Circ. 23391).
  The light curve can be modelled with an initial power-law decay with an index of alpha=0.3 (+0.5, -0.7), followed by a break at T+179 s to an alpha of 1.815 (+0.024, -0.023).
  A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.06 (+0.05, -0.04). The best-fitting absorption column is 5.3 (+1.9, -1.8) x 10^20 cm^-2, in excess of the Galactic value of 3.5 x 10^20 cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index of 1.54 (+0.17, -0.14) and a best-fitting absorption column of 5.2 (+4.9, -1.7) x 10^20 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 4.2 x 10^-11 (4.5 x 10^-11) erg cm^-2 count^-1.
  A summary of the PC-mode spectrum is thus:

  Total column:	     5.2 (+4.9, -1.7) x 10^20 cm^-2
  Galactic foreground: 3.5 x 10^20 cm^-2
  Excess significance: <1.6 sigma
  Photon index:	     1.54 (+0.17, -0.14)
  

  If the light curve continues to decay with a power-law decay index of 1.815, the count rate at T+24 hours will be 1.0 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 4.4 x 10^-14 (4.7 x 10^-14) erg cm^-2 s^-1.
  The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00869494.
  This circular is an official product of the Swift-XRT team.
• GCN Circular #23396
  Alan M. Watson (UNAM), Nat Butler (ASU), Alexander Kutyrev (GSFC), William H. Lee (UNAM), Michael G. Richer (UNAM), Ori Fox (STScI), J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (UVI), Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC), Jesús González (UNAM), Carlos Román-Zúñiga (UNAM), Harvey Moseley (GSFC), John Capone (UMD), V. Zach Golkhou (U. Wash.), and Vicki Toy (UMD) report:
  We observed the field of GRB 181030A (Sonbas et al., GCN Circ. 23389) with the Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on the 1.5m Harold Johnson Telescope at the Observatorio Astronómico Nacional on Sierra San Pedro Mártir from 2018/10 30.41 to 2018/10 30.53 UTC (8.40 to 11.29 hours after the BAT trigger), obtaining a total of 0.82 hours exposure in the r and i bands and 0.39 hours exposure in the Z, Y, J, and H bands.
  For a source within the XRT error circle, in comparison with the SDSS DR9 and 2MASS catalogs, we obtain the following upper limits (3-sigma):

    r	> 22.25
    i	> 22.11
    Z	> 21.07
    Y	> 20.80
    J	> 20.31
    H	> 19.61
  

  These magnitudes are in the AB system and are not corrected for Galactic extinction in the direction of the GRB.
  The afterglow has clearly faded since the early observations of Sonbas et al. (GCN Circ. 23389), Moskvitin & Spiridonova (GCN Circ. 23390), and Lipunov et al. (GCN Circ. 23392).
  We thank the staff of the Observatorio Astronómico Nacional in San Pedro Mártir.
• GCN Circular #23397
  J. R. Cummings (CPI), S. D. Barthelmy (GSFC), H. A. Krimm (NSF/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), E. Sonbas (Adiyaman Univ.), M. Stamatikos (OSU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):
  Using the data set from T-239 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 181030A (trigger #869494) (Sonbas et al., GCN Circ. 23389). The BAT ground-calculated position is RA, Dec = 146.916, 14.657 deg which is

    RA(J2000)  =  09h 47m 39.8s
    Dec(J2000) = +14d 39' 26.5"
  

  with an uncertainty of 1.1 arcmin, (radius, sys+stat, 90% containment). The partial coding was 71%.
  The mask-weighted light curve shows a long pulse that starts at ~T0 and peaks at ~T+70 s. The main pulse emission ends at ~T+200 s, with some weak emission lasting till ~T+400 s. T90 (15-350 keV) is 304.7 +- 76.9 sec (estimated error including systematics).
  The time-averaged spectrum from T+3.2 to T+443.0 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.77 +- 0.09. The fluence in the 15-150 keV band is 6.2 +- 0.3 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+71.33 sec in the 15-150 keV band is 0.8 +- 0.2 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/869494/BA/
• GCN Circular #23400
  S.W.K. Emery (UCL-MSSL) and E. Sonbas (Adiyaman Univ.) report on behalf of the Swift/UVOT team:
  The Swift/UVOT began settled observations of the field of GRB 181030A 152 s after the BAT trigger (Sonbas et al., GCN Circ. 23389). A fading source is detected in the initial UVOT exposures at a position consistent with the XRT position (Beardmore et al., GCN Circ. 23391) and also with SAO RAS (Moskvitin et al., GCN Circ. 23390) and MASTER Net (Lipunov et al., GCN Circ. 23392).
  Preliminary detections and 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           152          270          116        19.34 +/- 0.30
  white             3978         5614          393        >20.7
  v                 4389         6009          378        >18.9
  b                 3774        17487          635        >20.1
  u                 3569        17236         1278        >20.3
  uvw1              4799        11747          852        >20.2
  uvm2              4594        22498         1201        >20.7
  uvw2              4184         5819          393        >20.1
  

  The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.03 in the direction of the burst (Schlegel et al. 1998).