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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"

27296 results found.

  1. GRB 240101A: Swift-BAT refined analysis
  2. GRB 240101B: Swift-BAT refined analysis
  3. GRB 240101B: Swift-XRT refined Analysis
  4. GRB 240102A: Swift-XRT refined Analysis
  5. GRB 240102B (Fermi GBM trigger 725926335/240102925) is not a GRB
  6. GRB 240102A: LCOGT Optical Upper Limits
  7. Fermi trigger No 725857207: Global MASTER-Net observations report
  8. GRB240102A: BOOTES-6/DPRT optical upper limit
  9. GRB 240102B: Fermi GBM Final Real-time Localization
  10. GRB 240101B: MarSEC Observatory, Vicenza, Italy, UPPER LIMIT
  11. GRB 240102A: Swift detection of a burst
  12. GRB 240101B: Swift/UVOT Upper Limits
  13. GRB 240101A: Swift/UVOT Upper Limits
  14. GRB 240101A: Swift-XRT refined Analysis
  15. GRB 240101C: Fermi GBM Final Localization
  16. Swift GRB240101.85: Global MASTER-Net observations report
  17. GRB 240101B: Swift detection of a burst
  18. GRB 240101A: Swift detection of a burst
  19. Fermi trigger No 725806648: Global MASTER-Net observations report
  20. GRB231230A: Fermi GBM Observation
  21. GRB 231230A: Swift-XRT refined Analysis
  22. GRB 231230A: GOTO optical upper limits
  23. GRB 231230A: Swift/UVOT Upper Limits
  24. Fermi trigger No 725592555: Global MASTER-Net observations report
  25. GRB 231230A: Swift detection of a burst
  26. Swift GRB231230.06: Global MASTER-Net observations report
  27. GRB 231230A: Fermi GBM Final Real-time Localization
  28. GRB 231210B: BOOTES-7 optical upper limit
  29. LIGO/Virgo/KAGRA S231224e: Upper limits from Swift/BAT-GUANO
  30. IPN triangulation of GRB 231224A (short)
  31. Fermi trigger No 725143760: Global MASTER-Net observations report
  32. GRB 231224A: Fermi GBM Final Real-time Localization
  33. Fermi trigger No 724921799: Global MASTER-Net observations report
  34. GRB 231222B: Fermi GBM Detection
  35. LAT GRB231222.31: Global MASTER-Net observations report
  36. GRB 231222B: Fermi-LAT detection
  37. GRID detection of GRB 231215A
  38. GRB 231222A: Fermi GBM Final Real-time Localization
  39. GRB 231220A: Swift/BAT-GUANO arcminute localization of a long burst
  40. Fermi trigger No 724781422: Global MASTER-Net observations report
  41. GRB 231220A: Fermi GBM Final Real-time Localization
  42. Fermi trigger No 724698747: Global MASTER-Net observations report
  43. GRB 231219A: Fermi GBM Final Real-time Localization
  44. GRID detection of GRB 231205B
  45. GRID detection of GRB 231205A
  46. GRB 231216A: GAD Observatory, La Spezia, Italy upper limit
  47. GRB 231214B: Fermi GBM observation
  48. GRB 231216A: 10.4 m GTC optical upper limit
  49. GRB 231216A: Nanshan/HMT optical upper limit
  50. GRB 231216A: LCOGT Optical Upper Limits
  51. GRB 231216A: Osservatorio Astronomico Nastro Verde upper limit
  52. GRB 231215A: Osservatorio Astronomico Nastro Verde upper limit
  53. GRB 231216A: Swift-XRT refined Analysis
  54. GRB 231216A: AST3-3 YaoAn Optical Upper Limit
  55. GRB 231216A: REM NIR upper limits
  56. GRB 231216A: Swift/UVOT Upper Limits
  57. GRB 231216A: Swift-BAT refined analysis
  58. GRB 231215A: Swift-BAT refined analysis
  59. GRB 231214A: Swift-BAT refined analysis
  60. GRB 231216A: R-band observations from T120 at Observatoire de Haute-Provence
  61. GRB 231216A: GIT optical upper limit
  62. GRB 231216A: NOT optical upper limits
  63. GRB 231216A: BOOTES-2/TELMA optical upper limit
  64. Swift GRB231216.77: Global MASTER-Net observations report
  65. GRB 231216A: Swift detection of a burst
  66. Konus-Wind detection of GRB 231215A
  67. GRB 231215A: NOT optical observations
  68. GRB 231214A: Swift/UVOT Upper Limits
  69. GRB 231215A: GAD Observatory, La Spezia, Italy upper limit;
  70. GRB 231215A: Fermi GBM observation
  71. GRB 231215A: CALET Gamma-Ray Burst Monitor detection
  72. GRB 231215A : OHP/T193 optical afterglow detection
  73. GRB 231215A: Swift/UVOT Detection
  74. LIGO/Virgo/KAGRA S231215i: 3 counterpart neutrino candidate events from an IceCube neutrino search
  75. GRB 231215A: Swift-XRT refined Analysis
  76. GRB 231215A: BOOTES-4/MET optical detection
  77. GRB 231215A: AKO Optical Upper Limit
  78. GRB 231214A: Fermi GBM observation
  79. Fermi trigger No 724326442: Global MASTER-Net observations report
  80. GRB 231214A: REM optical/NIR upper limits
  81. GRB 231215A: GROWTH-India optical follow-up
  82. GRB 231215A : Nanshan/HMT optical observations
  83. GRB 231215A : MITSuME Akeno optical afterglow candidate detection
  84. GRB 231214A: Swift-XRT refined Analysis
  85. Swift GRB231215.41: Global MASTER-Net observations report
  86. GRB 231215A: Swift-XRT observations
  87. GRB 231215B: Fermi GBM Final Real-time Localization
  88. GRB 231215A: Swift detection of a burst
  89. GRB 231214A: Fermi-LAT detection
  90. GRB 231214B: Swift/BAT-GUANO detection of a burst
  91. GRB231214A: BOOTES-6/DPRT optical upper limit
  92. Fermi trigger No 724278269: Global MASTER-Net observations report
  93. Fermi trigger No 724233240: Global MASTER-Net observations report
  94. Swift GRB231214.85: Global MASTER-Net observations report
  95. GRB 231214A: Swift detection of a burst
  96. GRB 231214A: Fermi GBM Final Real-time Localization
  97. GRB 231210B: REM optical/NIR upper limits
  98. LIGO/Virgo/KAGRA S231206cc: Upper limits from Swift/BAT-GUANO
  99. LIGO/Virgo/KAGRA S231206ca: Upper limits from Swift/BAT-GUANO
  100. GRB 231212A: GECAM-C detection of a likely short burst

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