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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"

37733 results found.

  1. GRB 231230A: Swift-BAT refined analysis
  2. GRB 240101A: Swift-BAT refined analysis
  3. GRB 240101B: Swift-BAT refined analysis
  4. GRB 240102A: Enhanced Swift-XRT position
  5. GRB 240101B: Swift-XRT refined Analysis
  6. GRB 240102A: Swift-XRT refined Analysis
  7. GRB 240102B (Fermi GBM trigger 725926335/240102925) is not a GRB
  8. GRB 240102A: LCOGT Optical Upper Limits
  9. Fermi trigger No 725857207: Global MASTER-Net observations report
  10. GRB240102A: BOOTES-6/DPRT optical upper limit
  11. GRB 240102B: Fermi GBM Final Real-time Localization
  12. GRB 240101B: MarSEC Observatory, Vicenza, Italy, UPPER LIMIT
  13. GRB 240102A: Swift detection of a burst
  14. GRB 240101A: Terskol Zeiss-2000 optical observations
  15. GRB 240101C: GRBAlpha detection
  16. GRB 240101B: Swift/UVOT Upper Limits
  17. GRB 240101A: Swift/UVOT Upper Limits
  18. GRB 240101A: Swift-XRT refined Analysis
  19. GRB 240101B: Enhanced Swift-XRT position
  20. GRB 240101B: KAIT Optical Upper Limit
  21. GRB 240101A: KAIT Optical Upper Limit
  22. GRB 240101A: Enhanced Swift-XRT position
  23. GRB 240101C: Fermi GBM Final Localization
  24. GRB 240101B: Swift detection of a burst
  25. GRB 240101A: Swift detection of a burst
  26. Fermi trigger No 725806648: Global MASTER-Net observations report
  27. GRB231230A: Fermi GBM Observation
  28. GRB 231230A: Swift-XRT refined Analysis
  29. GRB 231230A: GOTO optical upper limits
  30. GRB 231230A: Enhanced Swift-XRT position
  31. GRB 231230A: Swift/UVOT Upper Limits
  32. GRB 231230A: NOT optical upper limits
  33. Fermi trigger No 725592555: Global MASTER-Net observations report
  34. GRB 231230A: Prompt enhanced Swift-XRT position
  35. GRB 231230A: Swift detection of a burst
  36. GRB 231230A: Fermi GBM Final Real-time Localization
  37. GRB 231210B: BOOTES-7 optical upper limit
  38. LIGO/Virgo/KAGRA S231224e: Upper limits from Swift/BAT-GUANO
  39. IPN triangulation of GRB 231224A (short)
  40. Fermi trigger No 725143760: Global MASTER-Net observations report
  41. GRB 231224A: Fermi GBM Final Real-time Localization
  42. GRB 231222B: GRBAlpha detection
  43. GRB 231222B: Swift-XRT afterglow detection
  44. Fermi trigger No 724921799: Global MASTER-Net observations report
  45. GRB 231222B: Fermi GBM Detection
  46. GRB 231222B: Fermi-LAT detection
  47. GRB 231222A: Tiled Swift observations
  48. IceCube-231211A: GRANDMA observations of PKS2047+098
  49. GRID detection of GRB 231215A
  50. GRB 231222A: Fermi GBM Final Real-time Localization
  51. GRB 231220A: Swift-XRT follow-up observations
  52. GRB 231220A: Swift ToO observations
  53. GRB 231220A: Swift/BAT-GUANO arcminute localization of a long burst
  54. Fermi trigger No 724781422: Global MASTER-Net observations report
  55. GRB 231220A: Fermi GBM Final Real-time Localization
  56. GRB 231210B: new optical transient detected with the Greenhill Observatory University of Tasmania within the BAT-Swift enhanced position
  57. Fermi trigger No 724698747: Global MASTER-Net observations report
  58. GRB 231219A: Fermi GBM Final Real-time Localization
  59. GRID detection of GRB 231205B
  60. GRID detection of GRB 231205A
  61. GRB 231216A: GAD Observatory, La Spezia, Italy upper limit
  62. GRB 231214B: Fermi GBM observation
  63. GRB 231216A: optical upper limits from the INAF Asiago Observatory
  64. GRB 231216A: 10.4 m GTC optical upper limit
  65. GRB 231215A: AMI-LA radio detection
  66. GRB 231216A: Nanshan/HMT optical upper limit
  67. GRB 231216A: LCOGT Optical Upper Limits
  68. GRB 231216A: Osservatorio Astronomico Nastro Verde upper limit
  69. GRB 231216A: Swift-XRT refined analysis correction
  70. GRB 231215A: Osservatorio Astronomico Nastro Verde upper limit
  71. GRB 231216A: Swift-XRT refined Analysis
  72. GRB 231216A: AST3-3 YaoAn Optical Upper Limit
  73. GRB 231216A: REM NIR upper limits
  74. GRB 231216A: Swift/UVOT Upper Limits
  75. GRB 231216A: Swift-BAT refined analysis
  76. GRB 231215A: Swift-BAT refined analysis
  77. GRB 231214A: Swift-BAT refined analysis
  78. GRB 231216A: R-band observations from T120 at Observatoire de Haute-Provence
  79. GRB 231216A: GIT optical upper limit
  80. GRB 231216A: NOT optical upper limits
  81. GRB 231216A: BOOTES-2/TELMA optical upper limit
  82. GRB 231215A: GRBAlpha detection
  83. GRB 231216A: Swift detection of a burst
  84. Konus-Wind detection of GRB 231215A
  85. GRB 231215A: optical afterglow detection from the INAF Asiago Observatory
  86. GRB 231215A: NOT optical observations
  87. GRB 231214A: Swift/UVOT Upper Limits
  88. GRB 231215A: Redshift from OSIRIS+ / GTC
  89. GRB 231205B: VZLUSAT-2 detection
  90. GRB 231204A: VZLUSAT-2 detection
  91. GRB 231215A: GAD Observatory, La Spezia, Italy upper limit;
  92. GRB 231215A: Fermi GBM observation
  93. GRB 231215A: CALET Gamma-Ray Burst Monitor detection
  94. GRB 231215A : OHP/T193 optical afterglow detection
  95. GRB 231215A: Swift/UVOT Detection
  96. GRB 231215A: Swift-XRT refined Analysis
  97. GRB 231215A: BOOTES-4/MET optical detection
  98. GRB 231215A: AKO Optical Upper Limit
  99. GRB 231215A: AGILE detection
  100. GRB 231214A: Fermi GBM observation

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