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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"

19662 results found.

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

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