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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"

36129 results found.

  1. GRB 240101B: Swift detection of a burst
  2. GRB 240101A: Swift detection of a burst
  3. GRB231230A: Fermi GBM Observation
  4. GRB 231230A: Swift-XRT refined Analysis
  5. GRB 231230A: GOTO optical upper limits
  6. GRB 231230A: Enhanced Swift-XRT position
  7. GRB 231230A: Swift/UVOT Upper Limits
  8. GRB 231230A: NOT optical upper limits
  9. GRB 231230A: Prompt enhanced Swift-XRT position
  10. GRB 231230A: Swift detection of a burst
  11. GRB 231230A: Fermi GBM Final Real-time Localization
  12. GRB 231210B: BOOTES-7 optical upper limit
  13. LIGO/Virgo/KAGRA S231224e: Upper limits from Swift/BAT-GUANO
  14. IPN triangulation of GRB 231224A (short)
  15. GRB 231224A: Fermi GBM Final Real-time Localization
  16. GRB 231222B: GRBAlpha detection
  17. GRB 231222B: Swift-XRT afterglow detection
  18. GRB 231222B: Fermi GBM Detection
  19. GRB 231222B: Fermi-LAT detection
  20. GRB 231222A: Tiled Swift observations
  21. GRID detection of GRB 231215A
  22. GRB 231222A: Fermi GBM Final Real-time Localization
  23. GRB 231220A: Swift-XRT follow-up observations
  24. GRB 231220A: Swift ToO observations
  25. GRB 231220A: Swift/BAT-GUANO arcminute localization of a long burst
  26. GRB 231220A: Fermi GBM Final Real-time Localization
  27. GRB 231210B: new optical transient detected with the Greenhill Observatory University of Tasmania within the BAT-Swift enhanced position
  28. GRB 231219A: Fermi GBM Final Real-time Localization
  29. GRID detection of GRB 231205B
  30. GRID detection of GRB 231205A
  31. GRB 231216A: GAD Observatory, La Spezia, Italy upper limit
  32. GRB 231214B: Fermi GBM observation
  33. GRB 231216A: optical upper limits from the INAF Asiago Observatory
  34. GRB 231216A: 10.4 m GTC optical upper limit
  35. GRB 231215A: AMI-LA radio detection
  36. GRB 231216A: Nanshan/HMT optical upper limit
  37. GRB 231216A: LCOGT Optical Upper Limits
  38. GRB 231216A: Osservatorio Astronomico Nastro Verde upper limit
  39. GRB 231216A: Swift-XRT refined analysis correction
  40. GRB 231215A: Osservatorio Astronomico Nastro Verde upper limit
  41. GRB 231216A: Swift-XRT refined Analysis
  42. GRB 231216A: AST3-3 YaoAn Optical Upper Limit
  43. GRB 231216A: REM NIR upper limits
  44. GRB 231216A: Swift/UVOT Upper Limits
  45. GRB 231216A: Swift-BAT refined analysis
  46. GRB 231215A: Swift-BAT refined analysis
  47. GRB 231214A: Swift-BAT refined analysis
  48. GRB 231216A: R-band observations from T120 at Observatoire de Haute-Provence
  49. GRB 231216A: GIT optical upper limit
  50. GRB 231216A: NOT optical upper limits
  51. GRB 231216A: BOOTES-2/TELMA optical upper limit
  52. GRB 231215A: GRBAlpha detection
  53. GRB 231216A: Swift detection of a burst
  54. Konus-Wind detection of GRB 231215A
  55. GRB 231215A: optical afterglow detection from the INAF Asiago Observatory
  56. GRB 231215A: NOT optical observations
  57. GRB 231214A: Swift/UVOT Upper Limits
  58. GRB 231215A: Redshift from OSIRIS+ / GTC
  59. GRB 231205B: VZLUSAT-2 detection
  60. GRB 231204A: VZLUSAT-2 detection
  61. GRB 231215A: GAD Observatory, La Spezia, Italy upper limit;
  62. GRB 231215A: Fermi GBM observation
  63. GRB 231215A: CALET Gamma-Ray Burst Monitor detection
  64. GRB 231215A : OHP/T193 optical afterglow detection
  65. GRB 231215A: Swift/UVOT Detection
  66. GRB 231215A: Swift-XRT refined Analysis
  67. GRB 231215A: BOOTES-4/MET optical detection
  68. GRB 231215A: AKO Optical Upper Limit
  69. GRB 231215A: AGILE detection
  70. GRB 231214A: Fermi GBM observation
  71. Konus-Wind detection of GRB 231210B
  72. ATCA observations of GRB 231210B
  73. GRB 231215A: Enhanced Swift-XRT position
  74. GRB 231214A: REM optical/NIR upper limits
  75. GRB 231215A: GROWTH-India optical follow-up
  76. GRB 231215A : Nanshan/HMT optical observations
  77. GRB 231215A: AstroSat CZTI detection
  78. GRB 231215A : MITSuME Akeno optical afterglow candidate detection
  79. GRB 231214A: Swift-XRT refined Analysis
  80. GRB 231215A: Mondy optical bright afterglow detection
  81. GRB 231214A: AstroSat CZTI detection
  82. GRB 231215C: MASTER OT detection
  83. GRB 231215A: Swift-XRT observations
  84. GRB 231215B: Fermi GBM Final Real-time Localization
  85. GRB 231215A: Swift detection of a burst
  86. GRB 231214A: Fermi-LAT detection
  87. GRB 231214A: Enhanced Swift-XRT position
  88. GRB 231214B: Swift/BAT-GUANO detection of a burst
  89. GRB231214A: BOOTES-6/DPRT optical upper limit
  90. GRB 231214A: Swift detection of a burst
  91. GRB 231214A: Fermi GBM Final Real-time Localization
  92. GRB 231210B: REM optical/NIR upper limits
  93. LIGO/Virgo/KAGRA S231206cc: Upper limits from Swift/BAT-GUANO
  94. LIGO/Virgo/KAGRA S231206ca: Upper limits from Swift/BAT-GUANO
  95. GRB 231212A: GECAM-C detection of a likely short burst
  96. GRB 231210B: MeerLICHT afterglow observations
  97. GRB 231210B: Swift-BAT refined analysis
  98. GRB 231210B: Swift-XRT refined Analysis
  99. GRB 231210B: Enhanced Swift-XRT position
  100. GRB 231210B: VLT/X-shooter redshift

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