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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"

19663 results found.

  1. Trigger 1236151: Swift detection of EXO 0748-676
  2. IPN triangulation of GRB 240607A
  3. Konus-Wind detection of GRB 240606B
  4. GRB 240606B: Fermi GBM Observation
  5. Swift Trigger 1235109: consistent with noise and not astrophysical
  6. GRB 240606B: GECAM-B detection a long burst
  7. GRB 240606B: Swift-XRT afterglow detection
  8. Swift GRB240606.15: Global MASTER-Net observations report
  9. GRB 240606B: Swift ToO observations
  10. GRB 240606B: Swift/BAT-GUANO arcminute localization of a burst
  11. Swift Trigger 1235109: a possible GRB 240606A
  12. IPN triangulation of GRB 240531A (short)
  13. Swift Trigger 1232755: likely consistent with noise and not astrophysical
  14. LIGO/Virgo/KAGRA S240601co: Upper limits from Swift/BAT-GUANO
  15. LIGO/Virgo/KAGRA S240530a: Upper limits from Swift/BAT-GUANO
  16. Swift Trigger 1232465: consistent with noise
  17. GRB 240603B: Swift detection of a possible burst
  18. GRB 240529A: MASTER prompt OT detection
  19. GRB 240529A: OSN optical detection
  20. Swift Trigger 1232465 is not a GRB
  21. GRB 240529A: 1.3m DFOT Optical observations
  22. Konus-Wind detection of GRB 240529A
  23. IPN triangulation of the initial episode of GRB 240529A
  24. GRB 240529A: MAAO 0.7m telescope optical afterglow detection
  25. GRB 240529A: Insight-HXMT/HE detection
  26. GRB 240529A: GROWTH-India optical follow-up
  27. LIGO/Virgo/KAGRA S240527fv: Upper limits from Swift/BAT-GUANO
  28. LIGO/Virgo/KAGRA S240525p: Upper limits from Swift/BAT-GUANO
  29. GRB 240529A: Skynet Optical Observations
  30. GRB 240529A: Swift-BAT refined analysis
  31. GRB 240529A: Swift-XRT refined Analysis
  32. GRB240529A: BOOTES-6/DPRT optical detection
  33. GRB 240529A: Swift/UVOT Detection
  34. GRB 240529A: NOT optical observations
  35. GRB 240529A: AstroSat CZTI detection
  36. GRB 240529A: GOTO optical afterglow detection
  37. GRB 240527B: Swift-XRT afterglow detection
  38. GRB 240529A: Enhanced Swift-XRT position
  39. GRB 240529A: Swift detection of a burst with an optical counterpart
  40. Swift GRB240529.12: Global MASTER-Net observations report
  41. GRB 240527B: Fermi-LAT detection
  42. GRB 240523A: Swift-BAT refined analysis
  43. GRB 240523A: Swift-XRT refined Analysis
  44. GRB 240523A: Enhanced Swift-XRT position
  45. GRB 240523A: Swift detection of a burst
  46. GRB 240521B: Fermi GBM Observation
  47. GRB 240513A: Swift-XRT afterglow detection
  48. GRB 240521B: Swift/BAT-GUANO arcminute localization of a long burst
  49. LIGO/Virgo/KAGRA S240515m: Upper limits from Swift/BAT-GUANO
  50. LIGO/Virgo/KAGRA S240514x: Upper limits from Swift/BAT-GUANO
  51. LIGO/Virgo/KAGRA S240513ei: Upper limits from Swift/BAT-GUANO
  52. GRB 240504A: VZLUSAT-2 detection
  53. GRB 240516A: Swift/UVOT Upper Limits
  54. GRB 240516A: Swift-BAT refined analysis
  55. GRB 240516A ATCA radio observations
  56. IPN triangulation of GRB 240514B (short)
  57. GRB 240513A: Swift ToO observations
  58. GRB 240516A: AstroSat CZTI detection
  59. GRB 240516A: Swift-XRT refined Analysis
  60. GRB 240514E: A possible candidate BD-21 1074
  61. GRB 240516A: Fermi GBM Observation
  62. GRB 240516A: GOTO optical upper limit
  63. GRB 240516A: Swift detection of a burst
  64. Swift GRB240516.15: Global MASTER-Net observations report
  65. GRB 240513A: Swift-XRT observations
  66. LIGO/Virgo/KAGRA S240507p: Upper limits from Swift/BAT-GUANO
  67. LIGO/Virgo/KAGRA S240505av: Upper limits from Swift/BAT-GUANO
  68. LIGO/Virgo/KAGRA S240505av: Upper limits from Swift/BAT-GUANO
  69. GRB 240513A: Tiled Swift observations
  70. GRB 240513A: Fermi-LAT detection
  71. GRB 240511A: Fermi GBM Observation
  72. GRB 240511A: Swift-BAT refined analysis
  73. GRB 240511A: J-band observations with WINTER
  74. GRB 240511A: Enhanced Swift-XRT position
  75. GRB 240511A : MITSuME Akeno optical upper limits
  76. GRB 240511A: Swift-XRT refined Analysis
  77. Swift GRB 240511A: Global MASTER-Net observations report
  78. GRB 240511A: Prompt enhanced Swift-XRT position
  79. GRB 240511A: Swift detection of a burst
  80. GRB 240504A: Fermi GBM Observation
  81. IPN triangulation of GRB 240504A
  82. GRB 240504A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  83. GRB 240415A 1.3m DFOT Optical upper limit
  84. LIGO/Virgo S240422ed: Swift XRT observation of EP240426a
  85. LVK S240422ed: Further Swift-XRT followup of three sources
  86. LIGO/Virgo/KAGRA S240422ed: Magellan Follow-up Observations of Swift/XRT candidates
  87. LIGO/Virgo/KAGRA S240422ed: 2.5m PRL Telescope follow-up of the Swift/XRT source S240422ed_X190
  88. LIGO/Virgo/KAGRA S240422ed: X-ray Upper Limits from EP-FXT for the Potential Electromagnetic Counterparts Reported by Swift and DECam
  89. LIGO/Virgo/KAGRA S240422ed: SRG/eROSITA archival upper limits for Swift/XRT candidates
  90. GRB 240419B: Swift-BAT refined analysis
  91. GRB 240421B: Swift-BAT refined analysis
  92. LIGO/Virgo/KAGRA S240422ed: Himalayan Chandra Telescope follow-up of the Swift/XRT source S240422ed_X101
  93. IceCube-240424A - IceCube observation of a high-energy neutrino candidate track-like event
  94. LIGO/Virgo/KAGRA S240422ed: X-ray Upper Limits from EP-WXT for the Potential Electromagnetic Counterparts Reported by Swift and DECam
  95. LIGO/Virgo S240422ed: Swift-XRT detection of 3 possible counterparts
  96. LIGO/Virgo/KAGRA S240422ed: NOT J-band upper limit on the Swift/XRT source S240422ed_X61
  97. LIGO/Virgo/KAGRA S240422ed: X-ray Upper Limits from EP-WXT for the Three Potential Electromagnetic Counterparts Reported So Far
  98. GRB 240421B: GRBAlpha detection
  99. LIGO/Virgo/KAGRA S240422ed: WINTER J-band upper limits on the Swift/XRT source S240422ed_X61
  100. LIGO/Virgo/KAGRA S240422ed: GW-MMADS DECam upper limits on the Swift/XRT source S240422ed_X61

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