Skip to main content
JSON Notices via Email, Kafka Cron Jobs, Submitter Profile, GCN is Hiring. See news and announcements

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"

19666 results found.

  1. GRB 121123A: Swift detection of a burst with optical counterpart
  2. GRB 121108A: optical upper limit
  3. IPN Triangulation of GRB 121118B (long/intense)
  4. GRB 121117A: GROND confirmation of the UVOT afterglow candidate
  5. Swift-BAT trigger 538575 is not astrophysical
  6. GRB 121117A: Swift/UVOT Observations
  7. GRB 121117A: Swift-XRT refined Analysis
  8. GRB 121117A: MASTER prompt optical limit
  9. GRB 121117A, Swift-BAT refined analysis
  10. GRB 121117A: ROTSE-III Optical Limits
  11. GRB 121117A: BOOTES-3 early optical upper limit
  12. GRB 121117A: Swift detection of a burst
  13. Swift trigger 538575: Magellan Observations
  14. Trigger 538084: Swift detection of XTE J1739-302
  15. GRB 121108A: Swift-XRT refined Analysis
  16. GRB 121108A: Swift/UVOT Upper Limits
  17. GRB 121108A, Swift-BAT refined analysis
  18. GRB 121108A: Enhanced Swift-XRT position
  19. GRB 121108A: Optical observations
  20. GRB 121108A: MASTER early prompt optical limit
  21. GRB 121108A: TAROT Calern observatory optical observations
  22. GRB 121108A: Swift detection of a burst
  23. GRB 121031A: Fermi GBM detection
  24. GRB 121028A: Swift/UVOT Upper Limits
  25. GRB 121031A, Early peak observed with Swift-BAT
  26. GRB 121102A: Swift/UVOT Upper Limits
  27. GRB 121031A: Swift/UVOT Upper Limits
  28. GRB 121031A: Swift-XRT refined Analysis
  29. GRB 121102A: Enhanced Swift-XRT position
  30. GRB 121031A: Enhanced Swift-XRT position
  31. GRB 121102A: Swift-XRT refined Analysis
  32. GRB 121102A: Swift-BAT refined analysis
  33. GRB 121025A: Confirmation of the X-ray afterglow
  34. GRB 121102A: Swift detection of a burst
  35. GRB 121027A: sub-mm upper limit
  36. GRB 121031A: Swift-BAT refined analysis
  37. GRB 121031A: Prompt enhanced Swift-XRT position
  38. GRB 121031A: Swift detection of a burst
  39. Swift Quick-look and HEASARC are back online
  40. GRB 121027A: Swift/UVOT Possible Detection
  41. GRB 121028A: near-IR observations at Calar Alto
  42. GRB 121028A: RAPTOR Limits During Gamma-Ray Emitting Interval
  43. Swift Quick-look and HEASARC will be offline for due to hurricane Sandy
  44. GRB 121027A: MASTER early prompt optical limit
  45. GRB 121027A: Swift-XRT refined Analysis
  46. GRB 121027A: Brightening IR counterpart
  47. GRB 121028A: Swift-XRT refined Analysis
  48. GRB 121028A: Enhanced Swift-XRT position
  49. GRB 121028A: Swift-BAT refined analysis
  50. GRB 121027A: Enhanced Swift-XRT position
  51. GRB 121028A: Swift detection of a burst
  52. GRB 121011A: optical observations
  53. GRB 121027A: nIR afterglow candidate with AAT
  54. GRB 121027A: Swift-BAT refined analysis
  55. GRB 121025A: Swift-XRT observation
  56. GRB 121027A: MAXI/GSC detection 40 minutes after the Swift Trigger
  57. GRB 121027A: Swift detection of a burst
  58. Swift Quick-look and HEASARC will be offline for 24 hours this weekend
  59. Swift-BAT trigger 536502 is not astrophysical
  60. GRB 121024A: Swift/UVOT Observations
  61. GRB 121024A: Swift-BAT refined analysis
  62. GRB 121024A: Enhanced Swift-XRT position
  63. GRB 121024A: PAIRITEL NIR Detection
  64. GRB 121024A: Swift-XRT refined Analysis
  65. GRB 121024A: GROND Detection of the Optical/NIR Afterglow
  66. Skynet PROMPT/Dolomiti observations of GRB121024A
  67. GRB 121024A: TAROT Calern observatory optical detection of a bright counterpart
  68. GRB 121024A: Swift detection of a burst with an optical counterpart
  69. Swift Trigger 536502 is likely a noise fluctuation in coincidence with SAX J1818.6-1703
  70. GRB 121011A: early optical light curve
  71. GRB 121017A: Swift/UVOT Upper Limits
  72. GRB 121017A: Swift-XRT refined Analysis
  73. GRB 121017A: GROND Observations
  74. GRB 121017A: Swift-BAT refined analysis
  75. GRB 121017A: Enhanced Swift-XRT position
  76. GRB 121017A: 1.23m CAHA R-band observations
  77. GRB 121017A: BOOTES-2/TELMA observations
  78. GRB 121017A: Swift detection of a burst
  79. GRB 121011A Suzaku WAM observation of the prompt emission
  80. GRB 121014A: Swift-BAT refined analysis
  81. GRB 121014A: Swift detection of a burst
  82. GRB 121011A: Swift/UVOT Detection
  83. GRB 121011A: Fermi GBM observation
  84. GRB 121011A: Fermi-LAT detection of a burst
  85. Swift-BAT trigger 535733 is not astrophysical
  86. GRB 121011A: Swift-XRT refined Analysis
  87. GRB 121011A: optical observations
  88. GRB 121011A, Swift-BAT refined analysis
  89. Swift-BAT refined analysis of the SGR 1806-20 outburst (trigger 535747)
  90. GRB 121011A: Enhanced Swift-XRT position
  91. GRB 121011A: MASTER-Net early OT light curve
  92. GRB 121011A: Swift detection of a burst with optical afterglow
  93. Trigger 535747: Swift detection of an outburst from SGR1806-20
  94. Trigger 535733: Swift possible detection of SAX J1828.5-1037
  95. GRB 120927A: optical upper limit
  96. GRB 120804A: Late-time Chandra observation
  97. GRB 121001A: GROND Afterglow Confirmation
  98. GRB 121001A: Swift/UVOT Upper Limits
  99. GRB 121001A: Swift-XRT refined Analysis
  100. GRB 121001A: Enhanced Swift-XRT Position

Advanced

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