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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').
Advanced Search

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"
  1. Swift Trigger 924641 is an outburst from MAXI J1807+132
  2. LIGO/Virgo S190910d: Coverage and upper limits from MAXI/GSC observations
  3. LIGO/Virgo S190910d : no neutrino counterpart candidate in ANTARES search
  4. LIGO/Virgo S190910d: Upper limits from Fermi-GBM Observations
  5. LIGO/Virgo S190910d: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  6. ZTF19abvizsw: No counterpart candidates from Swift/BAT targeted search
  7. LIGO/Virgo S190910d: No counterpart candidates in HAWC observations
  8. LIGO/Virgo S190910d: Identification of a GW compact binary merger candidate
  9. LIGO/Virgo S190910d Global MASTER-Net observations report
  10. LIGO/Virgo S190910d: Upper limits from IceCube neutrino searches
  11. GRB 190910A: Fermi GBM Final Real-time Localization
  12. LIGO/Virgo S190814bv: ATCA monitoring of ASKAP J005547-270433/AT2019osy
  13. LIGO/Virgo S190814bv: VLA/JAGWAR monitoring of the 50% containment region
  14. LIGO/Virgo S190901ap: Gaia Photometric Alerts transient candidates
  15. LIGO/Virgo S190901ap : No significant candidates found in GRANDMA citizen science observations
  16. GRB 190901A: AstroSat CZTI detection
  17. ZTF19abvizsw/AT2019pim, search for GRB in SPI-ACS/INTEGRAL data
  18. Fermi trigger No 589561732 Global MASTER-Net observations report
  19. ZTF19abvizsw: 15GHz observations with AMI
  20. ZTF19abvizsw: AbAO and CrAO photometry
  21. GRB 190829A observations in CrAO, photometry of the SN
  22. Fermi trigger No 589487114 Global MASTER-Net observations report
  23. GRB 190823A: Swift-XRT afterglow detection
  24. GRB 190906B: Fermi GBM Final Real-time Localization
  25. IPN triangulation of GRB 190906A (short)
  26. GRB 190829A: GTC confirmation of an associated Type Ic-BL Supernova
  27. GRB 190829A: ATCA cm-band detection
  28. LIGO/Virgo S190901ap: ZTF19abwvals is a type-Ia SN near maximum
  29. LIGO/Virgo S190901ap: Second Epoch Hobby-Eberly Telescope observations of ZTF19abvionh
  30. Fermi trigger No 589419513 Global MASTER-Net observations report
  31. GRB 190905A: Fermi GBM Final Real-time Localization
  32. GRB 180620A: SEDM Observations
  33. Fermi GBM GCN 25668 Retraction
  34. LIGO/Virgo S190814bv: GRAWITA VST-ESO PARANAL observations and independent transient candidates discovery.
  35. GRB 190829A optical observation
  36. LIGO/Virgo S190901ap : No significant candidates in TAROT-GRANDMA
  37. LIGO/Virgo S190901ap: NOT spectroscopy of AT2019pjv
  38. GRB190829A: Keck LRIS spectroscopic confirmation of the accompanying supernova
  39. LIGO/Virgo S190901ap: No counterpart candidates in KAIT observations
  40. IPN triangulation of GRB 190903A (short)
  41. LIGO/Virgo S190901ap : GRAWITA spectroscopic observation of candidate MASTER OT J171434.95+280725.6
  42. Konus-Wind observation of GRB 190829A
  43. LIGO/Virgo S190901ap: Dabancheng-0.5m optical observations of AT2019pjv
  44. Swift XRT Detection of X-ray Emission from ZTF19abvizsw
  45. GRB 190829A: Liverpool Telescope observations of a slow supernova rise
  46. LIGO/Virgo S190901ap: Additional candidates from the Zwicky Transient Facility
  47. ZTF19abvizsw: COATLI Optical Observations
  48. LIGO/Virgo S190901ap: GOTO optical coverage and detection of AT2019pjv
  49. LIGO/Virgo S190901ap: GTC follow-up spectroscopic observations of ZTF19abvizsw
  50. GRB 190829A: MASTER confirmation of GROND SN
  51. GRB190829A: GROND detection of the accompanying SN
  52. LIGO/Virgo S190901ap : GRAWITA photometric observation of candidate ZTFabvizsw and GCN 25618 revision
  53. LIGO/Virgo S190901ap: MASTER OT J171434.95+280725.6/AT2019pjv detection
  54. LIGO/Virgo S190901ap: no counterpart candidate in the SVOM/GWAC observations
  55. LIGO/Virgo S190901ap: Upper limits from CALET observations.
  56. GRB 190901A: Insight-HXMT/HE detection
  57. LIGO/Virgo S190901ap: Upper limits from Insight-HXMT/HE observations
  58. Fermi trigger No 589263065 Global MASTER-Net observations report
  59. Liverpool Telescope observations of ZTF19abvizsw, a candidate untriggered GRB afterglow
  60. GRB 190904A: Fermi GBM Final Real-time Localization
  61. GRB 190829A: LCO Optical Afterglow Detection
  62. LIGO/Virgo S190901ap : SVOM/GWAC-F60A observation of transient ZTFabvizsw
  63. LIGO/Virgo S190901ap: Keck I LRIS spectroscopy of ZTF19abvizsw
  64. LIGO/Virgo S190901ap: Keck I LRIS spectroscopy of ZTF19abvionh
  65. Fermi trigger No 589223981 Global MASTER-Net observations report
  66. GRB 190903A: Fermi GBM detection
  67. GRB 190829A: MeerKAT radio observation
  68. LIGO/Virgo S190901ap: Additional observations from the Zwicky Transient Facility
  69. GRB 190903A: Fermi GBM Final Real-time Localization
  70. LIGO/Virgo S190901ap: GROWTH-India follow-up of ZTF19abvionh
  71. Chandra observations of GW170817 ~740-743 days since merger
  72. LIGO/Virgo S190901ap: Upper limits from AGILE-GRID observations
  73. LIGO/Virgo S190828l: no counterpart candidate in the SVOM/GWAC observations
  74. LIGO/Virgo S190828j: no counterpart candidate in the SVOM/GWAC observations
  75. GRB 190829A: Detection of radio afterglow with the uGMRT
  76. LIGO/Virgo S190901ap: No neutrino candidates at Pierre Auger Observatory
  77. LIGO/Virgo S190901ap: No counterpart candidates in Fermi-LAT observations
  78. LIGO/Virgo S190901ap: Hobby-Eberly Telescope VIRUS observations of ZTF19abvionh [correction on the peak]
  79. GRB 190829A: Flattening of optical light curve from continued Liverpool Telescope photometry
  80. LIGO/Virgo S190901ap: Hobby-Eberly Telescope VIRUS observations of ZTF19abvionh
  81. LIGO/Virgo S190814bv: ATCA observation of ASKAP J005547-270433/AT2019osy
  82. LIGO/Virgo S190901ap: Hobby-Eberly Telescope VIRUS observations of target galaxy; no obvious optical counterpart.
  83. LIGO/Virgo S190901ap : GRAWITA spectroscopic observation of candidate ZTFabvixoy
  84. LIGO/Virgo S190901ap : GRAWITA spectroscopic observation of candidate ZTFabvizsw
  85. LIGO/Virgo S190901ap: no counterpart candidates in the Swift/BAT Observations
  86. LIGO/Virgo S190901ap: Candidates from the Zwicky Transient Facility
  87. GRB 190831B: CALET Gamma-Ray Burst Monitor detection of a short burst
  88. LIGO/Virgo S190901ap: Updated Sky Localization
  89. LIGO/Virgo S190901ap: No counterpart candidates in AGILE-MCAL observations
  90. LIGO/Virgo S190901ap: Coverage and upper limits from MAXI/GSC observations
  91. LIGO/Virgo S190901ap : no neutrino counterpart candidate in ANTARES search
  92. LIGO/Virgo S190901ap: Upper limits from Fermi-GBM Observations
  93. LIGO/Virgo S190901ap Global MASTER-Net observations report
  94. Fermi GBM trigger 589060361/190901828 is not a GRB
  95. LIGO/Virgo S190901ap: No counterpart candidates in HAWC observations
  96. LIGO/Virgo S190901ap: Identification of a GW compact binary merger candidate
  97. LIGO/Virgo S190901ap: No counterpart candidates in INTEGRAL SPI-ACS,prompt observation
  98. LIGO/Virgo S190901ap: Upper limits from IceCube neutrino searches
  99. Fermi trigger No 589065714 Global MASTER-Net observations report
  100. GRB 190901A: BALROG localization (Fermi Trigger 589065714 / GRB 190901890)

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