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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"

21109 results found.

  1. IceCube Alert 191215.47: Global MASTER-Net observations report
  2. LIGO/Virgo S191213g: Upper limits from Insight-HXMT/HE observations
  3. LIGO/Virgo S191213g: LCOGT photometry of ZTF19acymaru/AT2019wnh
  4. LIGO/Virgo S191213g: Lulin Follow-up Observations of ZTF19acykzsk/AT2019wqj
  5. LIGO/Virgo S191213g: Liverpool Telescope spectroscopy of ZTF candidates
  6. LIGO/Virgo S191213g: Candidates from the Zwicky Transient Facility
  7. LIGO/Virgo S191213g: No transient candidates in CALET observations
  8. Fermi trigger No 597955752: Global MASTER-Net observations report
  9. LIGO/Virgo S191213g: No counterpart candidates in Fermi-LAT observations
  10. LIGO/Virgo S191213ai: Global MASTER-Net observations report
  11. LIGO/Virgo S191213g: no counterpart candidates in the Swift/BAT observations
  12. LIGO/Virgo S191213g: Upper limits from Fermi-GBM Observations
  13. LIGO/Virgo S191213g: upper limits from AGILE-GRID observations
  14. LIGO/Virgo S191213g: upper limits from AGILE-MCAL observations
  15. Fermi trigger No 597909938: Global MASTER-Net observations report
  16. LIGO/Virgo S191213g: Coverage and upper limits from MAXI/GSC observations
  17. LIGO/Virgo S191213g: Global MASTER-Net observations report
  18. LIGO/Virgo S191212q: Global MASTER-Net observations report
  19. Baksan Neutrino Observatory Alert 191211.1: Global MASTER-Net observations report
  20. Possible HAWC-detected GRB 191210A: Fermi-LAT Upper Limits
  21. Possible HAWC-detected GRB 191210A: Swift-XRT observations
  22. Fermi trigger No 597737032: Global MASTER-Net observations report
  23. LIGO/Virgo S191205ah: no counterpart candidate in SVOM/GWAC observations
  24. LIGO/Virgo S191205ah : No significant candidates in FRAM - TAROT – GRANDMA observations
  25. LIGO/Virgo S191205ah: MITSuME Observation of MASTER OT J123123.61-043847.2
  26. LIGO/Virgo S191204r: GRAWITA VST-ESO PARANAL observations.
  27. LIGO/Virgo S191205ah: MASTER OT detection
  28. IceCube-191204A : Upper limits from Insight-HXMT/HE observations
  29. LIGO/Virgo S191205ah: Upper limits from Insight-HXMT/HE observations
  30. LIGO/Virgo S191204r: Upper limits from Insight-HXMT/HE observations
  31. Fermi-LAT Gamma-ray Observations of IceCube-191204A
  32. LIGO/Virgo S191205ah: no counterpart candidates in the Swift/BAT observations
  33. LIGO/Virgo S191205ah: No counterpart candidates in Fermi-LAT observations
  34. LIGO/Virgo S191129u : No significant candidates in FRAM-TAROT-GRANDMA observations.
  35. LIGO/Virgo S191204r: No significant candidates in FRAM-TAROT-GRANDMA observations.
  36. LIGO/Virgo S191205ah: SAGUARO observations and identification of an optical candidate
  37. LIGO/Virgo S191205ah: Upper limits from Fermi-GBM Observations
  38. LIGO/Virgo S191204r: No transient candidates in CALET observations
  39. LIGO/Virgo S191204r: No counterpart candidates in Fermi-LAT observations
  40. LIGO/Virgo S191205ah: Coverage and upper limits from MAXI/GSC observations
  41. LIGO/Virgo S191205ah: upper limits from AGILE-MCAL observations
  42. LIGO/Virgo S191205ah: No counterpart candidates in HAWC observations
  43. LIGO/Virgo S191205ah: Global MASTER-Net observations report
  44. LIGO/Virgo S191204r: no counterpart candidates in the Swift/BAT observations
  45. GRB 191130A: Swift-XRT observations
  46. IceCube-191204A: Upper limits from Fermi-GBM Observations
  47. IceCube Alert 191204.95: Global MASTER-Net observations report
  48. LIGO/Virgo S191204r: Coverage and upper limits from MAXI/GSC observations
  49. LIGO/Virgo S191204r: upper limits from AGILE-GRID observations
  50. LIGO/Virgo S191204r: upper limits from AGILE-MCAL observations
  51. LIGO/Virgo S191204r: Global MASTER-Net observations report
  52. GRB 191130A: Swift ToO observations
  53. Fermi trigger No 597049044: Global MASTER-Net observations report
  54. LIGO/Virgo S191129u: No transient candidates in CALET observations
  55. Fermi trigger No 596786686: Global MASTER-Net observations report
  56. Fermi trigger No 596808579: Global MASTER-Net observations report
  57. LIGO/Virgo S191129u: Upper limits from Insight-HXMT/HE observations
  58. LIGO/Virgo S191129u: No counterpart candidates in Fermi-LAT observations
  59. LIGO/Virgo S191129u: No counterpart candidates in HAWC observations
  60. LIGO/Virgo S191129u: Coverage and upper limits from MAXI/GSC observations
  61. LIGO/Virgo S191129u: upper limits from AGILE/GRID observations
  62. LIGO/Virgo S191129u: upper limits from AGILE/MCAL observations
  63. LIGO/Virgo S191129u: Global MASTER-Net observations report
  64. Fermi trigger No 596690552: Global MASTER-Net observations report
  65. Baksan Neutrino Observatory Alert 191128.17: Global MASTER-Net observations report
  66. Baksan Neutrino Observatory Alert 191127.25: Global MASTER-Net observations report
  67. IceCube-191122A: Not observable by Fermi-GBM
  68. Fermi trigger No 596387570: Global MASTER-Net observations report
  69. Baksan Neutrino Observatory Alert 191124.13: Global MASTER-Net observations report
  70. Fermi-LAT Gamma-ray Observations of IceCube-191122A
  71. LIGO/Virgo S191124be: Global MASTER-Net observations report
  72. GRB 191123A: Swift/UVOT further analysis
  73. GRB 191123A: Swift/UVOT detection
  74. IceCube-191122A: INTEGRAL was inactive at the time of the event
  75. IceCube-191122A: Global MASTER-Net observations report
  76. GRB 191122A: Swift/UVOT Upper Limits
  77. GRB 191122A: BOOTES-4/MET optical limit
  78. GRB 191122A: CHES Optical Observations
  79. LIGO/Virgo S191120aj: Global MASTER-Net observations report
  80. Fermi-LAT Gamma-ray Observations of IceCube-191119A
  81. IceCube-191119A: Upper limits from Fermi-GBM Observations
  82. Swift GRB191115A: Global MASTER-Net observations report
  83. LIGO/Virgo S191110af: Upper limits from Konus-Wind observations
  84. Announcing the GW Treasure Map
  85. LIGO/Virgo S191110af: Potential pulsar counterparts
  86. GRB 191031D: CALET Gamma-Ray Burst Monitor detection
  87. LIGO/Virgo S191110af: Swift XRT observations, no secure afterglow found
  88. LIGO/Virgo S191110af: Upper limits from CALET observations.
  89. LIGO/Virgo S191110af: no counterpart candidates in the Swift/BAT observations
  90. LIGO/Virgo S191110af: No counterpart candidates in Fermi-LAT observations
  91. LIGO/Virgo S191110af: upper limits from AGILE/MCAL observations
  92. LIGO/Virgo S191110af: Upper limits from Fermi-GBM Observations
  93. LIGO/Virgo S191110af: Coverage and upper limits from MAXI/GSC observations
  94. LIGO/Virgo S191110af: Global MASTER-Net observations report
  95. LIGO/Virgo S191109d: No significant candidates in FRAM-TAROT-GRANDMA observations
  96. LIGO/Virgo S191110x: Global MASTER-Net observations report
  97. LIGO/Virgo S191109d: No counterpart candidates in Fermi-LAT observations
  98. LIGO/Virgo S191105e: No significant candidates in FRAM-TAROT-GRANDMA observations
  99. LIGO/Virgo S191105e: Upper limits from Insight-HXMT/HE observations
  100. LIGO/Virgo S191109d: no counterpart candidates in the Swift/BAT observations

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