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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"

27295 results found.

  1. GRB 240101B: Swift-BAT refined analysis
  2. GRB 240101B: Swift-XRT refined Analysis
  3. GRB 240102A: Swift-XRT refined Analysis
  4. GRB 240102B (Fermi GBM trigger 725926335/240102925) is not a GRB
  5. GRB 240102A: LCOGT Optical Upper Limits
  6. Fermi trigger No 725857207: Global MASTER-Net observations report
  7. GRB240102A: BOOTES-6/DPRT optical upper limit
  8. GRB 240102B: Fermi GBM Final Real-time Localization
  9. GRB 240101B: MarSEC Observatory, Vicenza, Italy, UPPER LIMIT
  10. GRB 240102A: Swift detection of a burst
  11. GRB 240101B: Swift/UVOT Upper Limits
  12. GRB 240101A: Swift/UVOT Upper Limits
  13. GRB 240101A: Swift-XRT refined Analysis
  14. GRB 240101C: Fermi GBM Final Localization
  15. Swift GRB240101.85: Global MASTER-Net observations report
  16. GRB 240101B: Swift detection of a burst
  17. GRB 240101A: Swift detection of a burst
  18. Fermi trigger No 725806648: Global MASTER-Net observations report
  19. GRB231230A: Fermi GBM Observation
  20. GRB 231230A: Swift-XRT refined Analysis
  21. GRB 231230A: GOTO optical upper limits
  22. GRB 231230A: Swift/UVOT Upper Limits
  23. Fermi trigger No 725592555: Global MASTER-Net observations report
  24. GRB 231230A: Swift detection of a burst
  25. Swift GRB231230.06: Global MASTER-Net observations report
  26. GRB 231230A: Fermi GBM Final Real-time Localization
  27. GRB 231210B: BOOTES-7 optical upper limit
  28. LIGO/Virgo/KAGRA S231224e: Upper limits from Swift/BAT-GUANO
  29. IPN triangulation of GRB 231224A (short)
  30. Fermi trigger No 725143760: Global MASTER-Net observations report
  31. GRB 231224A: Fermi GBM Final Real-time Localization
  32. Fermi trigger No 724921799: Global MASTER-Net observations report
  33. GRB 231222B: Fermi GBM Detection
  34. LAT GRB231222.31: Global MASTER-Net observations report
  35. GRB 231222B: Fermi-LAT detection
  36. GRID detection of GRB 231215A
  37. GRB 231222A: Fermi GBM Final Real-time Localization
  38. GRB 231220A: Swift/BAT-GUANO arcminute localization of a long burst
  39. Fermi trigger No 724781422: Global MASTER-Net observations report
  40. GRB 231220A: Fermi GBM Final Real-time Localization
  41. Fermi trigger No 724698747: Global MASTER-Net observations report
  42. GRB 231219A: Fermi GBM Final Real-time Localization
  43. GRID detection of GRB 231205B
  44. GRID detection of GRB 231205A
  45. GRB 231216A: GAD Observatory, La Spezia, Italy upper limit
  46. GRB 231214B: Fermi GBM observation
  47. GRB 231216A: 10.4 m GTC optical upper limit
  48. GRB 231216A: Nanshan/HMT optical upper limit
  49. GRB 231216A: LCOGT Optical Upper Limits
  50. GRB 231216A: Osservatorio Astronomico Nastro Verde upper limit
  51. GRB 231215A: Osservatorio Astronomico Nastro Verde upper limit
  52. GRB 231216A: Swift-XRT refined Analysis
  53. GRB 231216A: AST3-3 YaoAn Optical Upper Limit
  54. GRB 231216A: REM NIR upper limits
  55. GRB 231216A: Swift/UVOT Upper Limits
  56. GRB 231216A: Swift-BAT refined analysis
  57. GRB 231215A: Swift-BAT refined analysis
  58. GRB 231214A: Swift-BAT refined analysis
  59. GRB 231216A: R-band observations from T120 at Observatoire de Haute-Provence
  60. GRB 231216A: GIT optical upper limit
  61. GRB 231216A: NOT optical upper limits
  62. GRB 231216A: BOOTES-2/TELMA optical upper limit
  63. Swift GRB231216.77: Global MASTER-Net observations report
  64. GRB 231216A: Swift detection of a burst
  65. Konus-Wind detection of GRB 231215A
  66. GRB 231215A: NOT optical observations
  67. GRB 231214A: Swift/UVOT Upper Limits
  68. GRB 231215A: GAD Observatory, La Spezia, Italy upper limit;
  69. GRB 231215A: Fermi GBM observation
  70. GRB 231215A: CALET Gamma-Ray Burst Monitor detection
  71. GRB 231215A : OHP/T193 optical afterglow detection
  72. GRB 231215A: Swift/UVOT Detection
  73. LIGO/Virgo/KAGRA S231215i: 3 counterpart neutrino candidate events from an IceCube neutrino search
  74. GRB 231215A: Swift-XRT refined Analysis
  75. GRB 231215A: BOOTES-4/MET optical detection
  76. GRB 231215A: AKO Optical Upper Limit
  77. GRB 231214A: Fermi GBM observation
  78. Fermi trigger No 724326442: Global MASTER-Net observations report
  79. GRB 231214A: REM optical/NIR upper limits
  80. GRB 231215A: GROWTH-India optical follow-up
  81. GRB 231215A : Nanshan/HMT optical observations
  82. GRB 231215A : MITSuME Akeno optical afterglow candidate detection
  83. GRB 231214A: Swift-XRT refined Analysis
  84. Swift GRB231215.41: Global MASTER-Net observations report
  85. GRB 231215A: Swift-XRT observations
  86. GRB 231215B: Fermi GBM Final Real-time Localization
  87. GRB 231215A: Swift detection of a burst
  88. GRB 231214A: Fermi-LAT detection
  89. GRB 231214B: Swift/BAT-GUANO detection of a burst
  90. GRB231214A: BOOTES-6/DPRT optical upper limit
  91. Fermi trigger No 724278269: Global MASTER-Net observations report
  92. Fermi trigger No 724233240: Global MASTER-Net observations report
  93. Swift GRB231214.85: Global MASTER-Net observations report
  94. GRB 231214A: Swift detection of a burst
  95. GRB 231214A: Fermi GBM Final Real-time Localization
  96. GRB 231210B: REM optical/NIR upper limits
  97. LIGO/Virgo/KAGRA S231206cc: Upper limits from Swift/BAT-GUANO
  98. LIGO/Virgo/KAGRA S231206ca: Upper limits from Swift/BAT-GUANO
  99. GRB 231212A: GECAM-C detection of a likely short burst
  100. Fermi trigger No 724035412: Global MASTER-Net observations report

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