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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.

Advanced Search Examples (click to copy):

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

5557 results found.

  1. Konus-Wind detection of the intermediate flare from SGR 1935+2154
  2. Swift GRB211227.98: Global MASTER-Net observations report
  3. GRB 211225A: MITSuME Akeno optical upper limits
  4. Swift GRB 211225B: Global MASTER-Net observations report
  5. Fermi GRB 211225C: Global MASTER-Net observations report
  6. GRB 211225A/MAXI J0827-071: MAXI/GSC detection
  7. AGILE observations of a bright burst from SGR 1935+2154
  8. GRB 211218A: MITSuME Akeno optical upper limits
  9. GRB 211221A: MeerLICHT optical limits
  10. Fermi GRB 211219B: Global MASTER-Net observations report
  11. GRB 211218A, MAXI J0909-041: MAXI/GSC detection
  12. MAXI GRB211218.04: Global MASTER-Net observations report
  13. Fermi GRB 211216A: Global MASTER-Net observations report
  14. GRB 211211A: SAO RAS optical observations
  15. Swift GRB 211211A: Global MASTER-Net observations report
  16. GRB 211212A: Fermi GBM Final Real-time Localization
  17. Fermi GRB 211211B: Global MASTER-Net observations report
  18. Fermi trigger No 660868196: Global MASTER-Net observations report
  19. Fermi trigger No 660736561: Global MASTER-Net observations report
  20. Fermi GRB 211204B: Global MASTER-Net observations report
  21. Fermi GRB 211204A: Global MASTER-Net observations report
  22. GRB 211204A: Fermi GBM Final Real-time Localization
  23. Swift GRB 211203A: Global MASTER-Net observations report
  24. GRB 211203A: Swift detection of a burst
  25. Fermi GRB 211130A: Global MASTER-Net observations report
  26. GRB 211120548: Fermi GBM observation
  27. GRB 211118A: Fermi GBM detection
  28. HAWC-211123A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  29. Alert from the HAWC Burst Monitor HAWC-211123A
  30. Fermi trigger No 659106591: Global MASTER-Net observations report
  31. Fermi-LAT Gamma-ray Observations of IceCube-211117A
  32. IceCube-211117A : IceCube observation of a high-energy neutrino candidate track-like event
  33. Fermi trigger No 658755664: Global MASTER-Net observations report
  34. Fermi GRB 211112A: Global MASTER-Net observations report
  35. GRB 211110A: AstroSat CZTI detection
  36. Fermi trigger No 658214822: Global MASTER-Net observations report
  37. Fermi GRB 211109B: Global MASTER-Net observations report
  38. GRB 211102A: BALROG localization (Fermi Trigger 657533168 / GRB 211102338)
  39. GRB 211102A: Fermi GBM Final Real-time Localization
  40. Fermi GRB 211031A: Global MASTER-Net observations report
  41. GRB 211018A: Swift-XRT observations
  42. GRB 210610B: Sintesz-Newton/CrAO optical observations
  43. GRB 211023B: BOOTES-4/MET and 1.5m OSN optical upper limit
  44. Fermi GRB 211024A: Global MASTER-Net observations report
  45. IPN Triangulation of GRB 210927B
  46. Fermi GRB 211019A: Global MASTER-Net observations report
  47. Fermi trigger No 655673024: Global MASTER-Net observations report
  48. Fermi trigger No 655401471: Global MASTER-Net observations report
  49. Fermi trigger No 654854799: Global MASTER-Net observations report
  50. Fermi GRB 210929B: Global MASTER-Net observations report
  51. GRB 210929A: Fermi GBM Final Real-time Localization
  52. IPN triangulation of GRB 210925B
  53. GRB 210919A OSN 1.5m Source Confirmation
  54. GRB 210919A CAHA 2.2m Observations: Afterglow/Host Galaxy Candidate
  55. GRB 210919A: NOT upper limits
  56. GRB 210917A: Fermi GBM Final Real-time Localization
  57. Fermi GBM observation of another bright burst in the direction of SGR 1935+2154
  58. Fermi trigger No 653066776: Global MASTER-Net observations report
  59. Fermi trigger No 653084584: Global MASTER-Net observations report
  60. Fermi trigger No 653083551: Global MASTER-Net observations report
  61. Fermi trigger No 653072474: Global MASTER-Net observations report
  62. Fermi trigger No 653054042: Global MASTER-Net observations report
  63. Fermi trigger No 653049776: Global MASTER-Net observations report
  64. Fermi trigger No 653022153: Global MASTER-Net observations report
  65. Swift detection of a burst from SGR Swift J1555.2-5402
  66. Fermi trigger No 652927551: Global MASTER-Net observations report
  67. Fermi trigger No 652911693: Global MASTER-Net observations report
  68. Fermi trigger No 652906639: Global MASTER-Net observations report
  69. Fermi GRB 210909A: Global MASTER-Net observations report
  70. Fermi GRB 210904A: Global MASTER-Net observations report
  71. Swift GRB210903.59: Global MASTER-Net observations report
  72. Swift GRB210903.58: Global MASTER-Net observations report
  73. Fermi GRB 210903A: Global MASTER-Net observations report
  74. Fermi GRB 210903B: Global MASTER-Net observations report
  75. Integral GRB210829.14: Global MASTER-Net observations report
  76. Fermi GRB 210827A: Global MASTER-Net observations report
  77. GRB 210826A: Swift-XRT observations
  78. Swift detection of an outburst from SGR Swift J1555.2-5402
  79. GRB 210824A: Fermi GBM Observation
  80. GRB 210822A: GROND observations
  81. GRB 210824A: Fermi GBM Final Real-time Localization
  82. GRB 210820A: GROND observations
  83. Fermi GRB 210822B: Global MASTER-Net observations report
  84. Fermi GRB 210821A: Global MASTER-Net observations report
  85. GRB 210820A: LT optical upper limit
  86. GRB 210818A: Swift detection of a burst with an optical counterpart
  87. Swift GRB210807.74: Global MASTER-Net observations report
  88. Fermi GRB 210807C: Global MASTER-Net observations report
  89. GRB 210807A: Swift detection of a burst with an optical counterpart
  90. Fermi trigger No 649814537: Global MASTER-Net observations report
  91. GRB 210802A: MITSuME Okayama optical upper limits
  92. GRB 210802A: DDOTI Upper Limits
  93. GRB 210802A: BOOTES-2/TELMA optical upper limit
  94. GRB 210803A: BALROG localization (Fermi Trigger 649684549 / GRB 210803497)
  95. Fermi trigger No 649627691: Global MASTER-Net observations report
  96. GRB 210731A: Swift-BAT refined analysis
  97. GRB 210731A: Swift-XRT refined Analysis
  98. Fermi trigger No 649519043: Global MASTER-Net observations report
  99. GRB 210731A: MeerLICHT optical afterglow detection
  100. GRB210731A: Enhanced Swift-XRT position

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