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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"

21526 results found.

  1. GRB 240101B: KAIT Optical Upper Limit
  2. GRB 240101A: KAIT Optical Upper Limit
  3. GRB 240101A: Enhanced Swift-XRT position
  4. Swift GRB240101.85: Global MASTER-Net observations report
  5. GRB 240101B: Swift detection of a burst
  6. GRB 240101A: Swift detection of a burst
  7. GRB231230A: Fermi GBM Observation
  8. GRB 231230A: Swift-XRT refined Analysis
  9. GRB 231230A: GOTO optical upper limits
  10. GRB 231230A: Enhanced Swift-XRT position
  11. GRB 231230A: Swift/UVOT Upper Limits
  12. GRB 231230A: NOT optical upper limits
  13. GRB 231230A: Prompt enhanced Swift-XRT position
  14. GRB 231230A: Swift detection of a burst
  15. Swift GRB231230.06: Global MASTER-Net observations report
  16. GRB 231210B: BOOTES-7 optical upper limit
  17. Swift Triggers 1205103, 1205104, 1205107 and 1205110 are not astrophysical events
  18. LIGO/Virgo/KAGRA S231224e: Upper limits from Swift/BAT-GUANO
  19. GRB 231222B: Swift-XRT afterglow detection
  20. GRB 231222B: Fermi-LAT detection
  21. GRB 231222A: Tiled Swift observations
  22. GRID detection of GRB 231215A
  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 231210B: new optical transient detected with the Greenhill Observatory University of Tasmania within the BAT-Swift enhanced position
  27. GRID detection of GRB 231205B
  28. GRB 231216A: GAD Observatory, La Spezia, Italy upper limit
  29. GRB 231214B: Fermi GBM observation
  30. GRB 231216A: optical upper limits from the INAF Asiago Observatory
  31. GRB 231216A: 10.4 m GTC optical upper limit
  32. GRB 231216A: Nanshan/HMT optical upper limit
  33. GRB 231216A: LCOGT Optical Upper Limits
  34. GRB 231216A: Osservatorio Astronomico Nastro Verde upper limit
  35. GRB 231216A: Swift-XRT refined analysis correction
  36. GRB 231215A: Osservatorio Astronomico Nastro Verde upper limit
  37. GRB 231216A: Swift-XRT refined Analysis
  38. GRB 231216A: AST3-3 YaoAn Optical Upper Limit
  39. GRB 231216A: REM NIR upper limits
  40. GRB 231216A: Swift/UVOT Upper Limits
  41. GRB 231216A: Swift-BAT refined analysis
  42. GRB 231215A: Swift-BAT refined analysis
  43. GRB 231214A: Swift-BAT refined analysis
  44. GRB 231216A: R-band observations from T120 at Observatoire de Haute-Provence
  45. GRB 231216A: GIT optical upper limit
  46. GRB 231216A: NOT optical upper limits
  47. GRB 231216A: BOOTES-2/TELMA optical upper limit
  48. GRB 231215A: GRBAlpha detection
  49. Swift GRB231216.77: Global MASTER-Net observations report
  50. GRB 231216A: Swift detection of a burst
  51. Konus-Wind detection of GRB 231215A
  52. GRB 231215A: NOT optical observations
  53. GRB 231214A: Swift/UVOT Upper Limits
  54. GRB 231205B: VZLUSAT-2 detection
  55. GRB 231215A: GAD Observatory, La Spezia, Italy upper limit;
  56. GRB 231215A: Fermi GBM observation
  57. GRB 231215A: CALET Gamma-Ray Burst Monitor detection
  58. GRB 231215A: Swift/UVOT Detection
  59. GRB 231215A: Swift-XRT refined Analysis
  60. GRB 231215A: BOOTES-4/MET optical detection
  61. GRB 231215A: AKO Optical Upper Limit
  62. GRB 231215A: AGILE detection
  63. GRB 231214A: Fermi GBM observation
  64. Konus-Wind detection of GRB 231210B
  65. GRB 231215A: Enhanced Swift-XRT position
  66. GRB 231214A: REM optical/NIR upper limits
  67. GRB 231215A: GROWTH-India optical follow-up
  68. GRB 231215A : Nanshan/HMT optical observations
  69. GRB 231215A: AstroSat CZTI detection
  70. GRB 231215A : MITSuME Akeno optical afterglow candidate detection
  71. GRB 231214A: Swift-XRT refined Analysis
  72. GRB 231215A: Mondy optical bright afterglow detection
  73. GRB 231214A: AstroSat CZTI detection
  74. GRB 231215C: MASTER OT detection
  75. Swift GRB231215.41: Global MASTER-Net observations report
  76. GRB 231215A: Swift-XRT observations
  77. GRB 231215A: Swift detection of a burst
  78. GRB 231214A: Fermi-LAT detection
  79. GRB 231214A: Enhanced Swift-XRT position
  80. GRB 231214B: Swift/BAT-GUANO detection of a burst
  81. GRB231214A: BOOTES-6/DPRT optical upper limit
  82. Swift GRB231214.85: Global MASTER-Net observations report
  83. GRB 231214A: Swift detection of a burst
  84. GRB 231210B: REM optical/NIR upper limits
  85. LIGO/Virgo/KAGRA S231206cc: Upper limits from Swift/BAT-GUANO
  86. LIGO/Virgo/KAGRA S231206ca: Upper limits from Swift/BAT-GUANO
  87. GRB 231210B: MeerLICHT afterglow observations
  88. GRB 231210B: Swift-BAT refined analysis
  89. GRB 231210B: Swift-XRT refined Analysis
  90. GRB 231210B: Enhanced Swift-XRT position
  91. GRB 231210B: VLT/X-shooter redshift
  92. GRB 231210B: detection of the optical counterpart with the LCOGT 40cm telescope at Sutherland Observatory
  93. GRB 231210B: Swift detection of a burst with optical counterpart
  94. Swift GRB231210.90: Global MASTER-Net OT detection
  95. Swift GRB231210.90: Global MASTER-Net observations report
  96. IPN triangulation of GRB 231129C
  97. GRB231205B: Swift/UVOT Upper Limits
  98. GRB 231205B: Swift-BAT refined analysis
  99. GRB 231205B: 1.3m DFOT Optical upper limit
  100. GRB 231205B: optical upper limit in TSHAOand AbAO

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