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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"

26121 results found.

  1. IPN triangulation of GRB 240627A
  2. GRB 240619A: Host galaxy redshift from VLT/X-shooter
  3. EP240703b: EP-WXT detection of a fast X-ray transient
  4. EP240702a: Swift/XRT upper limit
  5. EP240703a: EP-WXT detection of a fast X-ray transient
  6. EP240702a: EP-WXT detection of a fast X-ray transient
  7. LIGO/Virgo/KAGRA S240627by: Upper limits from Swift/BAT-GUANO
  8. IPN triangulation of GRB 240619C
  9. GRB 240615A: SAI CMO J- band observations
  10. GRB 240624A: Swift-BAT refined analysis
  11. Konus-Wind detection of GRB 240619A
  12. GRB240624A: Fermi GBM Observation
  13. LIGO/Virgo/KAGRA S240622h: Upper limits from Swift/BAT-GUANO
  14. LIGO/Virgo/KAGRA S240621dy: Upper limits from Swift/BAT-GUANO
  15. LIGO/Virgo/KAGRA S240618ah: Upper limits from Swift/BAT-GUANO
  16. Swift GRB 240624A: Global MASTER-Net observations report
  17. GRB240615A: Gemini-North observations of the BAT and XRT positions
  18. GRB240615A: Gemini-North observations of the BAT and XRT positions
  19. GRB 240619A: detection of a radio counterpart with AMI-LA
  20. GRB 240624A: Swift detection of a burst
  21. GRB 240529A: JinShan optical observations
  22. IPN triangulation of GRB 240615A (short)
  23. EP240618a: Swift/XRT upper limit
  24. EP240617a: tentative Swift/XRT detection of the afterglow
  25. GRB 240619A: Swift-XRT probable afterglow detection
  26. GRB 240619A: Swift ToO observations
  27. GRB 240619A: GOTO candidate optical afterglow
  28. GRB 240615A: NOT optical observations
  29. GRB 240615A: possible transient detection from Wendelstein observations
  30. LIGO/Virgo S240615dg: Swift XRT observations, 39 X-ray sources
  31. GRB240615A: 1.3m DFOT optical upper limit
  32. LIGO/Virgo/KAGRA S240615ea: Upper limits from Swift/BAT-GUANO
  33. LIGO/Virgo/KAGRA S240615dg: Upper limits from Swift/BAT-GUANO
  34. GRB 240615A: J-band upper limits from WINTER
  35. GRB 240615A: Fermi GBM Observation
  36. GRB 240615A: Swift-XRT observations
  37. GRB 240615A: GECAM detection
  38. GRB 240615A: FLWO-1.2m optical upper limits
  39. Konus-Wind detection of GRB 240615A (short/hard)
  40. GRB 240615A: GOTO optical upper limits
  41. GRB 240615A: Swift ToO observations
  42. GRB 240615A: Swift/BAT-GUANO arcminute localization of a short burst
  43. EXO 0748-676: Swift-BAT refined analysis
  44. GRB240529A: 3.6m TNG NIR detection 8d after the burst
  45. GRB 240529A: LBT optical detection and late temporal decay
  46. GRB 240529A : MITSuME Akeno optical afterglow detection
  47. Trigger 1236151: Swift detection of EXO 0748-676
  48. IPN triangulation of GRB 240607A
  49. Konus-Wind detection of GRB 240606B
  50. GRB 240529A: NOEMA detection
  51. GRB 240606B: Fermi GBM Observation
  52. Swift Trigger 1235109: consistent with noise and not astrophysical
  53. GRB 240529A: radio detection with AMI-LA
  54. GRB 240606B: GECAM-B detection a long burst
  55. GRB 240606B: Swift-XRT afterglow detection
  56. Swift GRB240606.15: Global MASTER-Net observations report
  57. GRB 240606B: Swift ToO observations
  58. GRB 240606B: Swift/BAT-GUANO arcminute localization of a burst
  59. Swift Trigger 1235109: a possible GRB 240606A
  60. IPN triangulation of GRB 240531A (short)
  61. Swift Trigger 1232755: likely consistent with noise and not astrophysical
  62. LIGO/Virgo/KAGRA S240601co: Upper limits from Swift/BAT-GUANO
  63. LIGO/Virgo/KAGRA S240530a: Upper limits from Swift/BAT-GUANO
  64. Swift Trigger 1232465: consistent with noise
  65. GRB 240603B: Swift detection of a possible burst
  66. GRB 240529A: MASTER prompt OT detection
  67. GRB 240529A: OSN optical detection
  68. Swift Trigger 1232465 is not a GRB
  69. GRB 240529A: AKO Optical Afterglow Follow-Up Observations
  70. GRB 240529A: 1.3m DFOT Optical observations
  71. GRB 240529A : Mondy optical observations
  72. Konus-Wind detection of GRB 240529A
  73. IPN triangulation of the initial episode of GRB 240529A
  74. GRB 240529A: MAAO 0.7m telescope optical afterglow detection
  75. GRB 240529A: Insight-HXMT/HE detection
  76. GRB 240529A: optical photometry from Konkoly
  77. GRB 240529A: GROWTH-India optical follow-up
  78. GRB 240529A: T193/MISTRAL observations
  79. GRB 240529A: Redshift from GTC/OSIRIS+
  80. GRB 240529A: AKO Optical Afterglow Detection
  81. LIGO/Virgo/KAGRA S240527fv: Upper limits from Swift/BAT-GUANO
  82. LIGO/Virgo/KAGRA S240525p: Upper limits from Swift/BAT-GUANO
  83. GRB 240529A: Skynet Optical Observations
  84. GRB 240529A: Swift-BAT refined analysis
  85. GRB 240529A: Swift-XRT refined Analysis
  86. GRB240529A: BOOTES-6/DPRT optical detection
  87. GRB 240529A: Swift/UVOT Detection
  88. GRB 240529A: NOT optical observations
  89. GRB 240529A: AstroSat CZTI detection
  90. GRB 240529A: GOTO optical afterglow detection
  91. GRB 240527B: Swift-XRT afterglow detection
  92. GRB 240529A: Enhanced Swift-XRT position
  93. GRB 240529A: Swift detection of a burst with an optical counterpart
  94. Swift GRB240529.12: Global MASTER-Net observations report
  95. GRB 240527B: Fermi-LAT detection
  96. GRB 240523A: Swift-BAT refined analysis
  97. GRB 240523A: Swift-XRT refined Analysis
  98. GRB 240523A: Enhanced Swift-XRT position
  99. GRB 240523A: Swift detection of a burst
  100. GRB 240521B: Fermi GBM Observation

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