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"

42784 results found.

  1. GRB 061214(?): Swift detection of a possible burst
  2. GRB 061210: Suzaku WAM observation of the prompt emission
  3. Swift/BAT trigger #250033 is due to a known source during loss of
  4. GRB 061213: MASTER-VWF-Kislovodsk optical candidate
  5. GRB 061213: MASTER-VWF-Kislovodsk observations
  6. GRB 061210: Gemini/GMOS Observations
  7. GRB 061126: Radio Observations
  8. GRB061210: Radio Observations
  9. GRB061201, VLT optical decay: correction
  10. GRB 061126: a GRB detected off-axis by INTEGRAL
  11. GRB 061202: Suzaku WAM observation of the prompt emission
  12. GRB 061210: Swift-BAT detection of a short burst
  13. Optical Afterglow observations of GRB 061126
  14. GRB061126: optical observations
  15. GRB 060926: MASTER: discovery of the optical flare
  16. Corrections for Swift/UVOT Exposure Times for GRBs 061110B and 061121
  17. GRB 061201: UVOT Observations of a Fading Optical Afterglow
  18. GRB 061202: TORTOREM optical upper limits
  19. GRB 061201: VLT optical decay
  20. GRB 061201: SOAR Confirmation of Candidate Afterglow
  21. GRB061126 : NMSU 1.0m observations
  22. GRB 061202: Swift XRT refined analysis
  23. GRB061202: FRAM early follow-up limit
  24. GRB061202 optical limit by "Pi of the Sky"
  25. Konus-Wind observation of GRB 061201
  26. GRB061202: optical/NIR observations with REM
  27. GRB061202: Swift/UVOT Upper Limits
  28. GRB 061202, Swift-BAT refined analysis
  29. GRB 061202: Swift detection of a burst
  30. GRB 061201: Swift XRT Team refined analysis
  31. GRB 061201: VLT optical observations
  32. GRB 061201: Initial UVOT Observations
  33. GRB 061201, Swift-BAT refined analysis of the SHB
  34. GRB 061201: Swift detection of a short hard burst
  35. GRB 061201: Coincidence with a Galaxy Cluster
  36. GRB 061122: GETS observation
  37. GRB 061121, SMARTS optical/IR observations
  38. INT+WFC observations of GRB 061126
  39. GRB 061126: Possible Jet Break
  40. GRB 061121: Second Epoch ATCA Radio Observations
  41. GRB 061126: RAPTOR Optical Detection During Gamma-Ray Emission
  42. Swift XRT on-board boresight update
  43. GRB 061121: ATCA & WSRT Radio Observations
  44. GRB061121: optical observations
  45. GRB 061126: Early Super-LOTIS Observations
  46. GRB 061126: optical observation
  47. RHESSI Spectrum of GRB061126
  48. GRB 061126: Tautenburg afterglow observations
  49. GRB061126: Optical afterglow observations from MIRO
  50. GRB061126: Optical afterglow observations from MIRO
  51. GRB 061126 : SDSS Pre-Burst Observations
  52. GRB 061126: Swift-XRT refined analysis
  53. GRB 061126: Swift/UVOT Observations
  54. GRB 061126: SARA Observations
  55. GRB 061126: Early Detection of the IR Afterglow
  56. GRB 061126: Faulkes Telescope North Optical Observations
  57. GRB 061126: Swift/UVOT Afterglow Detection
  58. GRB 061126: XRT position
  59. GRB 061126: Swift detection of a burst
  60. GRB 061121: MDM Continued Monitoring
  61. GRB 061121: MDM Continuing Optical Decay
  62. GRB061121: optical observations
  63. GRB 061122: Candidate Optical Afterglow
  64. GRB 061121: Ep,i - Eiso correlation
  65. GRB 061121: MDM Optical Decay
  66. GRB061122: Swift/UVOT Optical Observations
  67. GRB061121: P60 Observations
  68. Radio detection of GRB 061121
  69. GRB061122: Swift-XRT position
  70. Konus-Wind observation of GRB 061122
  71. GRB 061121: MDM Optical Observations
  72. GRB 061121 declared "Burst of Interest" by Swift team
  73. RHESSI Spectrum of GRB061121
  74. Konus-Wind and Konus-A observations of GRB 061121
  75. INTEGRAL results on GRB 061122
  76. Swift-BAT trigger 239987 is not a GRB
  77. GRB 061122A: a long GRB detected by INTEGRAL
  78. GRB 061121: Swift/UVOT Observations
  79. GRB 061121: Swift-XRT Team Refined Analysis
  80. GRB 061121, Swift-BAT refined analysis
  81. GRB 061121 : Planned XMM-Newton observation
  82. GRB 061121: Optical observation at the KANATA 1.5m telescope
  83. GRB 061121: Faulkes Telescope North Optical Observation
  84. GRB061121: Spectroscopic Redshift
  85. GRB061121: Keck spectroscopic observations
  86. GRB 061121: Swift detection of a bright burst with an optical counterpart
  87. GRB 060605: NIR Observations
  88. GRB 050915B: optical afterglow
  89. GRB 060111B: Swift UVOT Refined Magnitudes
  90. Swift-BAT triggers 238544 and 238546 are not GRBs
  91. GRB 061110A: refined R-band analysis
  92. GRB 061110B: NIR Observations
  93. Swift TOO observations of GRB061110A
  94. GRB 061110A - VLT tentative redshift
  95. GRB 061110B: Swift XRT refined analysis
  96. GRB 061110B, Swift-BAT refined analysis
  97. GRB 061110B: VLT redshift
  98. GRB061110B: Optical observations at Crni Vrh
  99. GRB 061110B: NOT optical observations
  100. GRB 061110A: Swift XRT refined analysis

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Questions or comments?
Contact GCN directly.
Have you found a bug in GCN?
Open an issue.
Want to contribute code to GCN?
Get involved on GitHub.

gcn.nasa.gov

A service of the Astrophysics Science Division at NASA Goddard Space Flight Center

Looking for U.S. government information and services? Visit USA.gov