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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

21103 results found.

  1. Fermi trigger No 590335819: Global MASTER-Net observations report
  2. Alert from the HAWC Burst Monitor HAWC-190917A
  3. LIGO/Virgo S190915ak: no counterpart candidates in the Swift/BAT observations
  4. LIGO/Virgo S190915ak: Upper limits from Fermi-GBM Observations
  5. LIGO/Virgo S190915ak: No counterpart candidates in Fermi-LAT observations
  6. LIGO/Virgo S190915ak: Coverage and upper limits from MAXI/GSC observations
  7. GRB190915A: MASTER optical observation of BALROG Fermi GRB localization
  8. LIGO/Virgo S190915ak: Upper Limits from AGILE-GRID observations
  9. LIGO/Virgo S190915ak: No counterpart candidate in AGILE-MCAL observations
  10. LIGO/Virgo S190915ak: Global MASTER-Net observations report
  11. LIGO/Virgo S190910d : No significant candidates in TAROT-GRANDMA observations
  12. LIGO/Virgo S190814bv: No counterpart candidate after completion of GRAWITA VST-ESO PARANAL transient survey.
  13. Fermi trigger No 590038994: Global MASTER-Net observations report
  14. LIGO/Virgo S190910h: No counterpart candidates in Fermi-LAT observations
  15. Baksan Neutrino Observatory Alert 190913.27: Global MASTER-Net observations report
  16. LIGO/Virgo S190910d: No Counterparts in DDOTI/OAN Optical Observations
  17. LIGO/Virgo S190910h: Upper limits from CALET observations.
  18. LIGO/Virgo S190910d: No transient candidates in CALET observations.
  19. LIGO/Virgo S190910d and S190910h: No counterpart candidates in KAIT observations
  20. LIGO/Virgo S190910h: Four additional candidates from the Zwicky Transient Facility
  21. LIGO/Virgo S190910h: Candidates from the Zwicky Transient Facility
  22. LIGO/Virgo S190910d: Liverpool Telescope spectroscopy of ZTF19abyfazm
  23. LIGO/Virgo S190910h: no counterpart candidates in the Swift/BAT observations
  24. LIGO/Virgo S190910d: No counterpart candidates in Fermi-LAT observations
  25. LIGO/Virgo S190910h: No counterpart candidates in HAWC observations
  26. LIGO/Virgo S190910h: Upper limits from Fermi-GBM Observations
  27. LIGO/Virgo S190910h: No counterpart candidates in AGILE-MCAL observations
  28. LIGO/Virgo S190910h Global MASTER-Net observations report
  29. LIGO/Virgo S190910h: Coverage and upper limits from MAXI/GSC observations
  30. LIGO/Virgo S190910d: Candidates from the Zwicky Transient Facility
  31. LIGO/Virgo S190910d: no counterpart candidates in AGILE-GRID observations
  32. LIGO/Virgo S190910d: no counterpart candidates in the Swift/BAT Observations
  33. LIGO/Virgo S190910d: No counterpart candidates in AGILE-MCAL observations
  34. LIGO/Virgo S190910d: Coverage and upper limits from MAXI/GSC observations
  35. LIGO/Virgo S190910d: Upper limits from Fermi-GBM Observations
  36. LIGO/Virgo S190910d: No counterpart candidates in HAWC observations
  37. LIGO/Virgo S190910d Global MASTER-Net observations report
  38. LIGO/Virgo S190814bv: ATCA monitoring of ASKAP J005547-270433/AT2019osy
  39. LIGO/Virgo S190814bv: VLA/JAGWAR monitoring of the 50% containment region
  40. LIGO/Virgo S190901ap : No significant candidates found in GRANDMA citizen science observations
  41. Fermi trigger No 589561732 Global MASTER-Net observations report
  42. ZTF19abvizsw: 15GHz observations with AMI
  43. GRB 190829A observations in CrAO, photometry of the SN
  44. Fermi trigger No 589487114 Global MASTER-Net observations report
  45. GRB 190823A: Swift-XRT afterglow detection
  46. GRB 190829A: GTC confirmation of an associated Type Ic-BL Supernova
  47. GRB 190829A: ATCA cm-band detection
  48. LIGO/Virgo S190901ap: Second Epoch Hobby-Eberly Telescope observations of ZTF19abvionh
  49. Fermi trigger No 589419513 Global MASTER-Net observations report
  50. GRB 180620A: SEDM Observations
  51. LIGO/Virgo S190814bv: GRAWITA VST-ESO PARANAL observations and independent transient candidates discovery.
  52. LIGO/Virgo S190901ap : No significant candidates in TAROT-GRANDMA
  53. LIGO/Virgo S190901ap: NOT spectroscopy of AT2019pjv
  54. LIGO/Virgo S190901ap: No counterpart candidates in KAIT observations
  55. LIGO/Virgo S190901ap: Dabancheng-0.5m optical observations of AT2019pjv
  56. Swift XRT Detection of X-ray Emission from ZTF19abvizsw
  57. GRB 190829A: Liverpool Telescope observations of a slow supernova rise
  58. LIGO/Virgo S190901ap: Additional candidates from the Zwicky Transient Facility
  59. ZTF19abvizsw: COATLI Optical Observations
  60. LIGO/Virgo S190901ap: GOTO optical coverage and detection of AT2019pjv
  61. LIGO/Virgo S190901ap: GTC follow-up spectroscopic observations of ZTF19abvizsw
  62. LIGO/Virgo S190901ap: MASTER OT J171434.95+280725.6/AT2019pjv detection
  63. LIGO/Virgo S190901ap: no counterpart candidate in the SVOM/GWAC observations
  64. LIGO/Virgo S190901ap: Upper limits from CALET observations.
  65. LIGO/Virgo S190901ap: Upper limits from Insight-HXMT/HE observations
  66. Fermi trigger No 589263065 Global MASTER-Net observations report
  67. Liverpool Telescope observations of ZTF19abvizsw, a candidate untriggered GRB afterglow
  68. GRB 190829A: LCO Optical Afterglow Detection
  69. Fermi trigger No 589223981 Global MASTER-Net observations report
  70. GRB 190829A: MeerKAT radio observation
  71. LIGO/Virgo S190901ap: Additional observations from the Zwicky Transient Facility
  72. LIGO/Virgo S190901ap: GROWTH-India follow-up of ZTF19abvionh
  73. Chandra observations of GW170817 ~740-743 days since merger
  74. LIGO/Virgo S190901ap: Upper limits from AGILE-GRID observations
  75. LIGO/Virgo S190828l: no counterpart candidate in the SVOM/GWAC observations
  76. LIGO/Virgo S190828j: no counterpart candidate in the SVOM/GWAC observations
  77. GRB 190829A: Detection of radio afterglow with the uGMRT
  78. LIGO/Virgo S190901ap: No counterpart candidates in Fermi-LAT observations
  79. LIGO/Virgo S190901ap: Hobby-Eberly Telescope VIRUS observations of ZTF19abvionh [correction on the peak]
  80. GRB 190829A: Flattening of optical light curve from continued Liverpool Telescope photometry
  81. LIGO/Virgo S190901ap: Hobby-Eberly Telescope VIRUS observations of ZTF19abvionh
  82. LIGO/Virgo S190814bv: ATCA observation of ASKAP J005547-270433/AT2019osy
  83. LIGO/Virgo S190901ap: Hobby-Eberly Telescope VIRUS observations of target galaxy; no obvious optical counterpart.
  84. LIGO/Virgo S190901ap: no counterpart candidates in the Swift/BAT Observations
  85. LIGO/Virgo S190901ap: Candidates from the Zwicky Transient Facility
  86. LIGO/Virgo S190901ap: No counterpart candidates in AGILE-MCAL observations
  87. LIGO/Virgo S190901ap: Coverage and upper limits from MAXI/GSC observations
  88. LIGO/Virgo S190901ap: Upper limits from Fermi-GBM Observations
  89. LIGO/Virgo S190901ap Global MASTER-Net observations report
  90. LIGO/Virgo S190901ap: No counterpart candidates in HAWC observations
  91. Fermi trigger No 589065714 Global MASTER-Net observations report
  92. Fermi trigger No 589060361 Global MASTER-Net observations report
  93. LIGO/Virgo S190814bv : No significant candidates in TAROT-GRANDMA observations
  94. GRB 190829A: Continued fading inferred from Liverpool Telescope photometry
  95. LIGO/Virgo S190814bv: SOAR spectroscopy of DECam candidate AT2019ntp
  96. GRB 190829A: Keck LRIS spectroscopy of the optical afterglow
  97. LIGO/Virgo S190828j : No significant candidates in TAROT-GRANDMA observations
  98. LIGO/Virgo S190828l: No significant candidates in TAROT-GRANDMA observations
  99. GRB 190829A: Liverpool Telescope observations
  100. Fermi trigger No 588962322 Global MASTER-Net observations report

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