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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"

39458 results found.

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

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