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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

4254 results found.

  1. GRB 210929B: Fermi GBM Final Real-time Localization
  2. GRB 210929A: Fermi GBM Final Real-time Localization
  3. IPN triangulation of GRB 210925B
  4. GRB 210926A: GECAM detection
  5. GRB 210925A: GECAM detection
  6. GRB 210923B: GECAM detection
  7. GECAM observations of a series of bursts from SGR J1935+2154 (2021-09-15T14 to 2021-09-23T14)
  8. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 September 22
  9. IceCube Alert 210922.76: Global MASTER-Net observations report
  10. GRB 210919A: NOT upper limits
  11. Swift GRB 210919A: Global MASTER-Net observations report
  12. GECAM observations of bursts from SGR J1935+2154 (2021-09-13T01 to 2021-09-15T14)
  13. Konus-Wind observation of the recent SGR 1935+2154 activity
  14. GECAM observations of bursts from SGR J1935+2154 (2021-09-12T05 to 2021-09-13T01)
  15. AGILE observations of two bright bursts from SGR 1935+2154
  16. Fermi GBM observation of another bright burst in the direction of SGR 1935+2154
  17. Fermi trigger No 653151835: Global MASTER-Net observations report
  18. GRB 210912A: Mondy optical afterglow confirmation
  19. Swift GRB 210912A: Global MASTER-Net observations report
  20. GECAM observations of bursts from SGR J1935+2154 (2021-09-11T07 to 2021-09-12T08)
  21. Fermi trigger No 653084584: Global MASTER-Net observations report
  22. Fermi trigger No 653083551: Global MASTER-Net observations report
  23. Fermi trigger No 653066130: Global MASTER-Net observations report
  24. Fermi trigger No 653072474: Global MASTER-Net observations report
  25. Fermi trigger No 653054042: Global MASTER-Net observations report
  26. Fermi trigger No 653022153: Global MASTER-Net observations report
  27. Fermi GBM observation of a bright flare in the direction of SGR 1935+2154
  28. Konus-Wind detection of the second intermediate flare from SGR 1935+2154
  29. IPN triangulation of a bright burst from SGR 1935+2154
  30. GRB 210909B: GECAM detection
  31. GECAM observations of a series of bursts from SGR J1935+2154
  32. Swift detection of a burst from SGR Swift J1555.2-5402
  33. GECAM observation of a burst from SGR J1935+2154
  34. GECAM observation of a burst from SGR J1935+2154
  35. GRB 210619B: Maidanak and Assy optical observations, broken power law parametrization
  36. Fermi trigger No 652911693: Global MASTER-Net observations report
  37. Fermi trigger No 652906639: Global MASTER-Net observations report
  38. GECAM observation of a burst from SGR J1555.2-5402
  39. Fermi GBM trigger 652585475 / 210906073 is not a GRB
  40. Fermi trigger No 652585475: Global MASTER-Net observations report
  41. GRB 210827B: GECAM detection
  42. Fermi GBM observation of a burst from SGR J1555.2-5402
  43. Integral GRB210829.17: Global MASTER-Net observations report
  44. Integral GRB210829.14: Global MASTER-Net observations report
  45. Fermi GRB 210827A: Global MASTER-Net observations report
  46. POLAR detection of a SGR-like burst
  47. GRB 210824A: MITSuME Akeno optical upper limits
  48. Swift detection of an outburst from SGR Swift J1555.2-5402
  49. GRB 210822A: GECAM refined analysis
  50. Konus-Wind detection of GRB 210822A
  51. Fermi GRB 210822B: Global MASTER-Net observations report
  52. GRB 210822A: Nanshan/NEXT optical observations
  53. GRB 210822A: GECAM detection
  54. GRB 210820A: LT optical upper limit
  55. Fermi GRB 210813A: Global MASTER-Net observations report
  56. SGR 1935+2154: SPI INTEGRAL observations on 2021 August 5
  57. Fermi GRB 210807C: Global MASTER-Net observations report
  58. Fermi trigger No 650046564: Global MASTER-Net observations report
  59. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 August 5
  60. IPN Triangulation of a bright burst from SGR 1935+2154
  61. Fermi trigger No 649814537: Global MASTER-Net observations report
  62. Fermi trigger No 649684549: Global MASTER-Net observations report
  63. Swift GRB210731.62: Global MASTER-Net observations report
  64. GRB 210731A: MeerLICHT optical afterglow detection
  65. GRB 210730A: Campo Imperatore optical observations
  66. GRB 210726A: Chandra detection of the X-ray afterglow
  67. GRB 210730A: Swift detection of a burst near M82
  68. Fermi trigger No 648959581: Global MASTER-Net observations report
  69. Fermi trigger No 648868114: Global MASTER-Net observations report
  70. Fermi trigger No 648602917: Global MASTER-Net observations report
  71. GRB 210719A: GECAM detection
  72. IceCube-210717A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  73. GECAM detection of a short burst from SGR J1935+2154
  74. Recent activity of SGR 1935+2154 as observed by CGBM
  75. Fermi trigger No 647805873: Global MASTER-Net observations report
  76. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 10
  77. GECAM detection of a short burst from SGR J1935+2154
  78. Fermi trigger No 647641569: Global MASTER-Net observations report
  79. Fermi trigger No 647624281: Global MASTER-Net observations report
  80. GECAM detection of a short burst from SGR J1935+2154
  81. GECAM detection of a short burst from SGR 1935+2154
  82. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 7
  83. GECAM detection of a short burst from SGR 1935+2154
  84. Fermi trigger No 647365516: Global MASTER-Net observations report
  85. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 6
  86. Fermi GBM Observations of SGR J1935+2154
  87. Swift-BAT detection of a burst from SGR 1935+2154
  88. GECAM detection of a bright short burst from SGR 1935+2154
  89. Integral GRB210707.02: Global MASTER-Net observations report
  90. INTEGRAL detection of a burst from SGR 1935+2154
  91. IceCube-210629A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  92. Fermi-LAT Gamma-ray Observations of IceCube-210629A
  93. GRB 210627B: GECAM detection
  94. IceCube Alert 210629.76: Global MASTER-Net observations report
  95. IceCube-210629A - IceCube observation of a high-energy neutrino candidate track-like event
  96. Fermi trigger No 646443989: Global MASTER-Net observations report
  97. Fermi GRB 210627A: Global MASTER-Net observations report
  98. GRB 210627A: Fermi GBM Final Real-time Localization
  99. Fermi GRB 210626A: Global MASTER-Net observations report
  100. Fermi GRB 210625A: Global MASTER-Net observations report

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