Skip to main content
Updates to LVK & CHIME Notices, Schema v7.2.3! See news and announcements

GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

28039 results found.

  1. GRB070125: Swift-XRT Refined Analysis
  2. GRB 070125: SARA detection in R
  3. GRB 070125: P60 Optical Afterglow Candidate
  4. GRB 070126?: Swift detection of a possible burst
  5. GRB070125 redshift request
  6. IPN localization of GRB070124 (short duration, hard spectrum)
  7. GRB 070110: Ep,i - Eiso correlation
  8. GRB 070107: Suzaku WAM observation of the prompt emission
  9. GRB070110: Swift XRT Team refined analysis
  10. GRB 070110, Swift-BAT refined analysis
  11. GRB070107 Swift/UVOT Observations of a Fading Optical Afterglow
  12. GRB 070110: Swift detection of a burst with a possible optical afterglow
  13. GRB 070107: Possible UVOT Afterglow
  14. GRB 070107, Swift-BAT refined analysis
  15. GRB 070107: Swift detection of a burst
  16. VLA observation of GRB 061222B
  17. VLA detection of GRB 061222A
  18. GRB070103: APO SPIcam i' and z' limits
  19. GRB070103: KPNO 4m+FLAMINGOS J limit
  20. GRB 070103: Swift/UVOT Upper limits
  21. GRB070103: Swift XRT refined analysis
  22. GRB 070103, Swift-BAT refined analysis
  23. GRB 070103: NOT observations
  24. GRB 070103: TAROT Calern observatory optical observations
  25. Retractions of previous Swift-BAT triggers
  26. erratum : SDSS Pre-burst Observations of GRB061126
  27. GRB 061210: Swift/XRT Astrometry Correction
  28. GRB 050826: MDM Redshift
  29. GRB 061222A: Confirmation of Gemini Afterglow Candidate
  30. GRB 061222A: Xinglong Optical Limit
  31. GRB 061222A: Gemini Afterglow Candidate
  32. GRB 061222B, Swift-BAT refined analysis
  33. GRB061222A Swift/UVOT: Upper Limits
  34. GRB 061222B: Swift/UVOT Upper limits
  35. GRB 061222B: Observation with the KANATA 1.5m telescope
  36. GRB 061222A: Observation with the KANATA 1.5m telescope
  37. GRB 061222B: BOOTES-IR optical observations
  38. GRB 061222B: SARA upper limit
  39. GRB 061217: Magellan host galaxy redshift
  40. GRB 061222A, Swift-BAT refined analysis
  41. GRB 061222B: REM NIR/optical observations
  42. GRB 061222B: TAROT La Silla observatory optical observations
  43. GRB 061222B: Swift detection of a burst
  44. GRB 061222b: optical afterglow
  45. GRB 061222A: Prompt ROTSE-III Optical Limits
  46. GRB 061222: Swift detection of a burst
  47. GRB 061218: TAROT La Silla observatory optical observations
  48. GRB 061217: TAROT Calern observatory optical observations
  49. GRB 061218: TORTOREM optical upper limits
  50. GRB 061218, Swift-BAT refined analysis
  51. GRB061217: VLT NIR observations
  52. GRB 061218, SMARTS optical/IR observations
  53. GRB 061218: REM prompt observations
  54. Swift triggers (#251863) on a possible burst
  55. GRB061217: Swift/UVOT refined analysis.
  56. GRB 061217: optical observations at Calar Alto
  57. GRB061217 - Swift/XRT refined analysis
  58. GRB 061217, Swift-BAT refined analysis
  59. GRB 061217: Magellan Observations
  60. GRB 061217: REM prompt observations
  61. GRB 061217: ROTSE-III Optical Limits
  62. GRB061210: Swift/UVOT observations
  63. GRB 061210: Swift XRT analysis - Possible counterparts
  64. GRB 061210: Gemini/GMOS Observations
  65. GRB 061126: Radio Observations
  66. GRB061210: Radio Observations
  67. GRB 061202: Suzaku WAM observation of the prompt emission
  68. GRB 061210, Swift-BAT refined analysis of the SHB
  69. Optical Afterglow observations of GRB 061126
  70. GRB 060926: MASTER: discovery of the optical flare
  71. GRB 061201: UVOT Observations of a Fading Optical Afterglow
  72. GRB 061202: TORTOREM optical upper limits
  73. GRB 061201: VLT optical decay
  74. GRB 061201: SOAR Confirmation of Candidate Afterglow
  75. GRB061202: FRAM early follow-up limit
  76. GRB061202 optical limit by "Pi of the Sky"
  77. GRB061202: optical/NIR observations with REM
  78. GRB061202: Swift/UVOT Upper Limits
  79. GRB 061202, Swift-BAT refined analysis
  80. GRB 061202: Swift detection of a burst
  81. GRB 061201: VLT optical observations
  82. GRB 061201: Initial UVOT Observations
  83. GRB 061201, Swift-BAT refined analysis of the SHB
  84. GRB 061201: Swift detection of a short hard burst
  85. INT+WFC observations of GRB 061126
  86. Swift XRT on-board boresight update
  87. GRB 061126: optical observation
  88. GRB 061126: Tautenburg afterglow observations
  89. GRB061126: Optical afterglow observations from MIRO
  90. GRB061126: Optical afterglow observations from MIRO
  91. GRB 061126 : SDSS Pre-Burst Observations
  92. GRB 061126: Swift-XRT refined analysis
  93. GRB 061126: Swift/UVOT Observations
  94. GRB 061126, Swift-BAT refined analysis
  95. GRB 061126: Early Detection of the IR Afterglow
  96. GRB 061126: Swift/UVOT Afterglow Detection
  97. GRB 061122: Candidate Optical Afterglow
  98. GRB 061121: Ep,i - Eiso correlation
  99. GRB061122: Swift/UVOT Optical Observations
  100. GRB061121: P60 Observations

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Looking for U.S. government information and services? Visit USA.gov