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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"

32766 results found.

  1. GRB 220107A: AbAO and Terskol optical observations
  2. GRB 220107B: MITSuME Akeno optical upper limits
  3. GRB 220107B: Nanshan/NEXT optical upper limits and host galaxy candidate
  4. GRB 220107A: Nanshan/NEXT optical observations
  5. GRB 220107A: Swift/UVOT Detection
  6. GRB 220107B: Fermi GBM observations
  7. GRB 220107A: MITSuME Akeno optical observation
  8. GRB 220107B: AstroSat CZTI detection
  9. GRB 220107B: Swift-XRT afterglow detection
  10. GRB 220107A: Swift-XRT afterglow detection
  11. GRB 220107A: AstroSat CZTI detection
  12. GRB 220107B: Tiled Swift observations
  13. GRB 220107A: Fermi GBM observations
  14. GRB 220107A: Swift ToO observations
  15. Fermi GRB 220107A: Global MASTER-Net observations report
  16. GRB 220107A: Swift/BAT-GUANO arcminute localization
  17. GRB 220101A: Tautenburg observations
  18. GRB 220101A: Continued Mondy optical observations
  19. GRB 220101A: further TNG NIR observations
  20. GRB 220101A: continued 1.3m DFOT Optical Observations
  21. GRB 220104A: Fermi GBM Observation
  22. GRB 220101A: Mondy optical observations
  23. GRB 220101A: 3rd LCO Optical Observation
  24. GRB 220101A: iTelescope optical observations
  25. GRB 211227A: Lijiang 2.4m Telescope Optical Observations
  26. GRB 220101A: VLA detection
  27. GRB 220101A: 1.3m DFOT observations
  28. GRB 220101A: LCO Continued Optical Observations
  29. GRB 220104A：GECAM detection
  30. Fermi GRB 220104A: Global MASTER-Net observations report
  31. GRB 211229B: Fermi GBM observation
  32. Fermi GRB 220103A: Global MASTER-Net observations report
  33. GRB 211227A: Gemini South Optical Observations
  34. GRB 211229B: Swift/BAT-GUANO detection outside the coded FOV
  35. GRB 220101A: TNG NIR afterglow detection
  36. GRB 220101A: ALMA detection
  37. GRB 220101A: LCO Optical Observations
  38. GRB 220101A: Tautenburg observations
  39. GRB 220101A: Swift-BAT refined analysis
  40. GRB 220101A: GMG observation (2nd epoch)
  41. GRB 211231A: AstroSat CZTI detection
  42. GRB 220101A: OASDG optical observations
  43. GRB 220101A : Eiso equals the maximum isotropic GRB energy
  44. GRB 220101A: GMG observation
  45. GRB 220101A: Asiago spectroscopic and photometric detection
  46. GRB220101A: optical afterglow detection from Konkoly Observatory
  47. GRB 220101A: Fermi GBM Detection
  48. GRB 220101A: NOT redshift confirmation
  49. GRB 220101A: CAHA 2.2m/CAFOS detection
  50. GRB 220101A: Liverpool telescope imaging of a high-redshift afterglow
  51. GRB 220101A: Swift-XRT refined Analysis
  52. GRB 220101A: AGILE detection
  53. GRB 220101A: Xinglong-2.16m photometry and spectroscopy
  54. GRB 220101: Swift/UVOT Detection
  55. GRB 220101A: Fermi-LAT detection
  56. GRB 220101A: Correction to GCN 31347
  57. IPN triangulation of GRB 211219A
  58. GRB 211231A: GECAM detection
  59. GRB 211229B: AGILE detection
  60. GRB 211229A: Swift-XRT and UVOT observations
  61. GRB 211227A: Deep early CAHA 2.2m/CAFOS observation
  62. GRB 211229A: Fermi GBM observation
  63. GRB 211229B: GECAM detection
  64. Fermi GRB 211229B: Global MASTER-Net observations report
  65. GRB 211229A: Swift ToO observations
  66. GRB 211229A: Swift/BAT-GUANO arcminute localization
  67. GRB 211227A: CALET Gamma-Ray Burst Monitor detection
  68. GRB 211225B: CALET Gamma-Ray Burst Monitor detection
  69. GRB 211229A: GECAM detection
  70. Fermi GRB 211229A: Global MASTER-Net observations report
  71. GRB 211227A: Swift/UVOT Upper Limits
  72. GRB 211227A: Swift-XRT refined Analysis
  73. GRB 211227A: Swift-BAT refined analysis
  74. Konus-Wind detection of the intermediate flare from SGR 1935+2154
  75. GRB 211227A: A possible short GRB with extended emission at z = 0.228?
  76. GRB 211227A: Liverpool Telescope upper limits
  77. GRB 211227A: LCO Optical Observations
  78. GRB 211227A: Nanshan/NEXT optical observations and host galaxy candidate
  79. GRB 211227A: MAXI/GSC detection
  80. GRB 211221A: Swift/UVOT Upper Limits
  81. GRB 211226A: Swift/BAT-GUANO detection outside the coded FOV
  82. GRB 211225B: Swift-BAT refined analysis
  83. GRB 211225A: MITSuME Akeno optical upper limits
  84. Swift GRB 211225B: Global MASTER-Net observations report
  85. Fermi GRB 211225C: Global MASTER-Net observations report
  86. GRB 211211A: observations with the 3.6m Devasthal Optical Telescope
  87. GRB 211223C: Swift-BAT refined analysis
  88. Swift GRB 211223C: Global MASTER-Net observations report
  89. GRB 211223A: Insight-HXMT/HE detection
  90. Fermi GRB 211223B: Global MASTER-Net observations report
  91. Fermi GBM Sub-Threshold Detection of GRB 211221A
  92. Fermi GBM Sub-Threshold Detection of GRB 211207A
  93. GRB 211221A: Swift-BAT refined analysis
  94. GRB 211221A: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  95. GRB 211219B: AstroSat CZTI detection
  96. GRB 211219A: AstroSat CZTI detection
  97. Fermi GRB 211222A: Global MASTER-Net observations report
  98. GRB 211221A: Swift-XRT refined Analysis
  99. GRB 211218A: MITSuME Akeno optical upper limits
  100. GRB 211221A: MeerLICHT optical limits

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