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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"

39457 results found.

  1. IceCube-211216A: Upper limits from Fermi-GBM Observations
  2. Fermi trigger No 661417475: Global MASTER-Net observations report
  3. GRB 211217A: GECAM detection
  4. GRB 211216A: Swift/BAT-GUANO detection outside the coded FOV
  5. IceCube-211216B - IceCube observation of a high-energy neutrino candidate track-like event
  6. IceCube Alert 211216.99: Global MASTER-Net observations report
  7. Fermi GRB 211216B: Global MASTER-Net observations report
  8. GRB 211216B: GECAM detection
  9. IceCube Alert 211216.30: Global MASTER-Net observations report
  10. GRB 211216B: Fermi GBM Final Real-time Localization
  11. IceCube-211216A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  12. GRB 211211A: TNG NIR observations
  13. IceCube-211216A - IceCube observation of a high-energy neutrino candidate track-like event
  14. GRB 211216A: GECAM detection
  15. GRB 211216A: BALROG localization (Fermi Trigger 661329957 / GRB 211216282)
  16. Fermi GRB 211216A: Global MASTER-Net observations report
  17. GRB 211216A: Fermi GBM Final Real-time Localization
  18. GRB 211211A: Insight-HXMT/HE detection
  19. GRB 211211A - Gemini K-band detection
  20. GRB 211211A: SAO RAS optical observations
  21. GRB 211211A: AbAO optical observations
  22. GRB 211211A: GMG upper limit
  23. GRB 211211A: redshift estimation and SPI-ACS/INTEGRAL detection
  24. GRB 211211A: Very fast decay observed from CAFOS/2.2mCAHA
  25. GRB 211211A: Further observations from CAFOS/2.2m CAHA
  26. GRB 211211A: HCT and GIT optical follow up observations
  27. GRB 211211A: CALET Gamma-Ray Burst Monitor detection
  28. Fermi GRB 211212A: Global MASTER-Net observations report
  29. GRB 211211A: incorrect E_iso value in GCN 31221
  30. GRB 211211A: Swift/UVOT detection
  31. GRB 211211A: NOT optical spectroscopy
  32. GRB 211211B: GECAM detection
  33. Fermi GRB 211212B: Global MASTER-Net observations report
  34. GRB 211211A: Afterglow detection from CAFOS/2.2m CAHA
  35. GRB 211211A: MITSuME Akeno optical observation
  36. Swift GRB 211211A: Global MASTER-Net observations report
  37. GRB 211212B: Fermi GBM Final Real-time Localization
  38. GRB 211211A: LCO Optical Observations
  39. GRB 211211A: Nanshan/NEXT optical observations
  40. GRB 211211A: Swift-XRT refined Analysis
  41. GRB 211212A: Fermi GBM Final Real-time Localization
  42. GRB 211211A: Fermi GBM observation
  43. GRB 211211A: Swift-BAT refined analysis
  44. Fermi GRB 211211B: Global MASTER-Net observations report
  45. GRB 211211B: Fermi GBM Final Real-time Localization
  46. Fermi GRB 211211A: Global MASTER-Net observations report
  47. GRB 211211A: Enhanced Swift-XRT position
  48. GRB 211207A: Swift/UVOT Detection
  49. GRB 211211A: KAIT Optical Afterglow Candidate
  50. GRB 211211A: Swift detection of a bright burst
  51. GRB 211211A: Fermi GBM Final Real-time Localization
  52. Fermi trigger No 660868196: Global MASTER-Net observations report
  53. Fermi trigger No 660736561: Global MASTER-Net observations report
  54. GRB 211130A: MeerLICHT identification of possible afterglow candidate
  55. Fermi-LAT Gamma-ray Observations of IceCube-211208A
  56. IceCube-211208A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  57. IceCube-211208A - IceCube observation of a high-energy neutrino candidate track-like event
  58. IceCube Alert 211208.84: Global MASTER-Net observations report
  59. GRB 211207A: Swift-BAT refined analysis
  60. GRB 211207A: VLT/X-shooter redshift
  61. GRB 211204C: Fermi GBM detection
  62. GRB 211207A: Swift-XRT refined Analysis
  63. GRB 211207A: Enhanced Swift-XRT position
  64. Swift GRB 211207A: Global MASTER-Net observations report
  65. GRB 211207A: Swift detection of a burst with an optical counterpart
  66. GRB 211206A: Not observable by Fermi-GBM
  67. GRB 211206A: AstroSat CZTI detection
  68. GRB 211206B: AstroSat CZTI detection
  69. GRB 211204C: AstroSat CZTI detection
  70. IPN triangulation of GRB 211204C
  71. GRB 211206A: Swift/BAT-GUANO detection outside the coded FOV
  72. GRB 211206A: AGILE/MCAL detection of a burst
  73. GRB 211204C: Swift/BAT-GUANO detection outside the coded FOV
  74. GRB 211204C: GECAM detection
  75. Fermi GRB 211204C: Global MASTER-Net observations report
  76. GRB 211204C: Fermi GBM Final Real-time Localization
  77. Fermi GRB 211204B: Global MASTER-Net observations report
  78. GRB 211204B: Fermi GBM Final Real-time Localization
  79. Fermi GRB 211204A: Global MASTER-Net observations report
  80. GRB 211204A: Fermi GBM Final Real-time Localization
  81. GRB 211124A: Fermi GBM Observation
  82. Swift Trigger 1086826 (possible GRB 211203A) is likely not an astrophysical event
  83. Swift GRB 211203A: Global MASTER-Net observations report
  84. Fermi GBM Upper limits for GRB 211203A
  85. Konus-Wind detection of GRB 211130A
  86. IPN triangulation of GRB 211130A
  87. GRB 211203A: Swift detection of a burst
  88. GRB 211201A: GECAM detection
  89. GRB 211201A: Swift/BAT-GUANO detection likely outside the coded FOV
  90. GRB 211106A: Second HST Observation
  91. Fermi GRB 211201A: Global MASTER-Net observations report
  92. GRB 211201A: Fermi GBM Final Real-time Localization
  93. Fermi GRB 211130A: Global MASTER-Net observations report
  94. GRB 211130A: BALROG localization (Fermi Trigger 659978192 / GRB 211130636)
  95. GRB 211130A: Fermi GBM Final Real-time Localization
  96. GRB 211106A: GECAM detection
  97. GRB 211129A: Swift-BAT refined analysis
  98. GRB 211129A: Swift-XRT refined Analysis
  99. GRB 211129A: Swift/UVOT Upper Limits
  100. GRB 211106A: HST Observations

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