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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').
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"

4179 results found.

  1. GRB 211023A: continued 1.3m DFOT Optical Observations and possible jet break
  2. GRB 211024A: MITSuME Akeno optical observation
  3. GRB 211102B: GECAM detection
  4. Fermi GRB 211102A: Global MASTER-Net observations report
  5. GRB 211023B: MITSuME Akeno optical upper limits
  6. Fermi GRB 211031A: Global MASTER-Net observations report
  7. IPN triangulation of GRB 211022A
  8. GRB 211023A: Terskol optical observations
  9. GECAM detection of a short burst probably from SGR J1555.2-5402
  10. GRB 211024A: GECAM detection
  11. GRB 211022A: GECAM detection
  12. Fermi trigger No 656506979: Global MASTER-Net observations report
  13. GRB 211018A: Detection by GRBAlpha
  14. Fermi trigger No 656288898: Global MASTER-Net observations report
  15. Fermi trigger No 655673024: Global MASTER-Net observations report
  16. Swift Trigger 1078701: Mondy, CrAO, AbAO observations, possible optical counterpart
  17. Fermi trigger No 655646385: Global MASTER-Net observations report
  18. Fermi Gamma-ray Burst Monitor trigger 211008665/655401471 is not a GRB
  19. Fermi trigger No 655401471: Global MASTER-Net observations report
  20. GECAM observation of a burst from SGR J1555.2-5402
  21. SGR 1935+2154: Swift/BAT-GUANO detection and arcminute localization
  22. GRB 210928A: Swift-XRT analysis (replaces GCN 30914)
  23. GRB 210927B: GECAM detection
  24. GRB 210927A: GIT optical follow-up of ZTF21acdwctm.
  25. Fermi GRB 210929B: Global MASTER-Net observations report
  26. GRB 210929B: Fermi GBM Final Real-time Localization
  27. GRB 210929A: Fermi GBM Final Real-time Localization
  28. IPN triangulation of GRB 210925B
  29. GRB 210926A: GECAM detection
  30. GRB 210925A: GECAM detection
  31. GRB 210923B: GECAM detection
  32. GECAM observations of a series of bursts from SGR J1935+2154 (2021-09-15T14 to 2021-09-23T14)
  33. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 September 22
  34. IceCube Alert 210922.76: Global MASTER-Net observations report
  35. GRB 210919A: NOT upper limits
  36. Swift GRB 210919A: Global MASTER-Net observations report
  37. GECAM observations of bursts from SGR J1935+2154 (2021-09-13T01 to 2021-09-15T14)
  38. Konus-Wind observation of the recent SGR 1935+2154 activity
  39. GECAM observations of bursts from SGR J1935+2154 (2021-09-12T05 to 2021-09-13T01)
  40. AGILE observations of two bright bursts from SGR 1935+2154
  41. Fermi GBM observation of another bright burst in the direction of SGR 1935+2154
  42. Fermi trigger No 653151835: Global MASTER-Net observations report
  43. GRB 210912A: Mondy optical afterglow confirmation
  44. Swift GRB 210912A: Global MASTER-Net observations report
  45. GECAM observations of bursts from SGR J1935+2154 (2021-09-11T07 to 2021-09-12T08)
  46. Fermi trigger No 653084584: Global MASTER-Net observations report
  47. Fermi trigger No 653083551: Global MASTER-Net observations report
  48. Fermi trigger No 653066130: Global MASTER-Net observations report
  49. Fermi trigger No 653072474: Global MASTER-Net observations report
  50. Fermi trigger No 653054042: Global MASTER-Net observations report
  51. Fermi trigger No 653022153: Global MASTER-Net observations report
  52. Fermi GBM observation of a bright flare in the direction of SGR 1935+2154
  53. Konus-Wind detection of the second intermediate flare from SGR 1935+2154
  54. IPN triangulation of a bright burst from SGR 1935+2154
  55. GRB 210909B: GECAM detection
  56. GECAM observations of a series of bursts from SGR J1935+2154
  57. Swift detection of a burst from SGR Swift J1555.2-5402
  58. GECAM observation of a burst from SGR J1935+2154
  59. GECAM observation of a burst from SGR J1935+2154
  60. GRB 210619B: Maidanak and Assy optical observations, broken power law parametrization
  61. Fermi trigger No 652911693: Global MASTER-Net observations report
  62. Fermi trigger No 652906639: Global MASTER-Net observations report
  63. GECAM observation of a burst from SGR J1555.2-5402
  64. Fermi GBM trigger 652585475 / 210906073 is not a GRB
  65. Fermi trigger No 652585475: Global MASTER-Net observations report
  66. GRB 210827B: GECAM detection
  67. Fermi GBM observation of a burst from SGR J1555.2-5402
  68. Integral GRB210829.17: Global MASTER-Net observations report
  69. Integral GRB210829.14: Global MASTER-Net observations report
  70. Fermi GRB 210827A: Global MASTER-Net observations report
  71. POLAR detection of a SGR-like burst
  72. GRB 210824A: MITSuME Akeno optical upper limits
  73. Swift detection of an outburst from SGR Swift J1555.2-5402
  74. GRB 210822A: GECAM refined analysis
  75. Konus-Wind detection of GRB 210822A
  76. Fermi GRB 210822B: Global MASTER-Net observations report
  77. GRB 210822A: Nanshan/NEXT optical observations
  78. GRB 210822A: GECAM detection
  79. GRB 210820A: LT optical upper limit
  80. Fermi GRB 210813A: Global MASTER-Net observations report
  81. SGR 1935+2154: SPI INTEGRAL observations on 2021 August 5
  82. Fermi GRB 210807C: Global MASTER-Net observations report
  83. Fermi trigger No 650046564: Global MASTER-Net observations report
  84. Konus-Wind detection of a burst from SGR 1935+2154 on 2021 August 5
  85. IPN Triangulation of a bright burst from SGR 1935+2154
  86. Fermi trigger No 649814537: Global MASTER-Net observations report
  87. Fermi trigger No 649684549: Global MASTER-Net observations report
  88. Swift GRB210731.62: Global MASTER-Net observations report
  89. GRB 210731A: MeerLICHT optical afterglow detection
  90. GRB 210730A: Campo Imperatore optical observations
  91. GRB 210726A: Chandra detection of the X-ray afterglow
  92. GRB 210730A: Swift detection of a burst near M82
  93. Fermi trigger No 648959581: Global MASTER-Net observations report
  94. Fermi trigger No 648868114: Global MASTER-Net observations report
  95. Fermi trigger No 648602917: Global MASTER-Net observations report
  96. GRB 210719A: GECAM detection
  97. IceCube-210717A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  98. GECAM detection of a short burst from SGR J1935+2154
  99. Recent activity of SGR 1935+2154 as observed by CGBM
  100. Fermi trigger No 647805873: Global MASTER-Net observations report

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