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"

23460 results found.

  1. GRB100628A : MOA optical upper limit
  2. GRB 090709A: Host galaxy detection
  3. GRB 100628A: Swift/UVOT Upper Limits
  4. GRB100628A: RTT150 optical observations
  5. GRB 100628A: Swift XRT detection of a possible X-ray afterglow
  6. GRB 100628A: Swift detection of a short hard burst
  7. GRB 100614A: CrAO optical limit
  8. GRB 100625A: Swift/UVOT Upper Limits
  9. GRB 100625A : IRSF/SIRIUS NIR upper limit
  10. GRB 100625A: Enhanced Swift-XRT position
  11. GRB100625A : MOA optical upper limit
  12. GRB 100625A: Swift detection of a short hard burst
  13. GRB 100418A: late time optical observations
  14. GRB 100621A: IRSF/SIRIUS NIR Observation
  15. GRB 100621A MOA-II optical limit
  16. GRB 100621A: Swift/UVOT observations
  17. GRB 100621A: GROND observation of bright NIR afterglow
  18. GRB 100621A: Enhanced Swift-XRT position
  19. GRB 100621A: ROTSE-III Optical Limits
  20. GRB 100621A: Swift detection of a burst
  21. GRB 100606A: Optical Limits
  22. GRB 100619A: Swift/UVOT Upper Limits
  23. GRB 100619A: Enhanced Swift-XRT position
  24. GRB 100619A: Swift-BAT refined analysis
  25. GRB 100619A: Swift detection of a burst
  26. GRB 100614A: Gemini/NIRI Observations
  27. GRB 100615A: Gemini/NIRI Observations
  28. GRB 100615A: Swift/UVOT Upper Limits
  29. GRB 100614A: Swift/UVOT Upper Limits
  30. GRB 100614A: NOT optical upper limits
  31. GRB 100614A: MASTER-Net optical alert observations
  32. GRB 100615A: Fermi GBM detection
  33. GRB 100615A: Swift-BAT refined analysis
  34. GRB 100614A: Enhanced Swift-XRT position
  35. GRB 100615A: Enhanced Swift-XRT position
  36. GRB 100615A: GROND observations, upper limits
  37. GRB 100615A: PAIRITEL NIR Upper Limits
  38. GRB 100615A: NTT/Ultracam imaging
  39. GRB 100615A: Swift detection of a burst
  40. GRB 100614A: BOOTES-2/TELMA optical observations
  41. GRB 100614A: Swift detection of a burst
  42. GRB 100606A: GROND observations
  43. Trigger 424161: Swift/BAT trigger on XTE J1946+274/GRO J1944+26
  44. Radio detection of GRB100418a with ATCA
  45. GRB 100606A: Swift/UVOT Upper Limits
  46. GRB 100606A: Enhanced Swift-XRT position
  47. Swift Trigger 424040 is not a GRB
  48. GRB 100606A: Swift detection of a burst
  49. Swift detection of outburst from the SFXT IGR J18410-0535
  50. GRB 100111A: Maidanak optical observations
  51. GRB 100418A: Maidanak optical observations
  52. GRB 100513A: CrAO optical observations
  53. GRB 100514A: CrAO optical observations
  54. GRB 100526A: optical upper limit
  55. GRB 100528A: Faulkes Telescope North Detection
  56. GRB 100528A: GROND detection in all bands
  57. GRB 100528A: NOT optical observation
  58. Swift UVOT and UVOT-enhanced XRT position for GRB 100528A
  59. GRB100526B: GROND Upper limits
  60. GRB 100526B: Swift-XRT confirmation of fading afterglow
  61. GRB 100526B: Swift/UVOT Upper Limits
  62. GRB 100526A: Swift/UVOT Upper Limits
  63. GRB 100526A: Gemini/NIRI infrared afterglow candidate
  64. GRB 100526A: NOT optical upper limit
  65. GRB 100526B: Swift XRT/UVOT observations
  66. GRB 100526A: Enhanced Swift-XRT position
  67. GRB 100526B: Swift detection of a probable GRB
  68. GRB 100526A: MASTER-Net optical alert observations
  69. GRB 100526A: Swift detection of a burst
  70. GRB100522A: Suzaku WAM observation of the prompt emission
  71. GRB 100418A: Subaru late-time optical imaging and spectroscopy
  72. GRB 100522A: GROND observations, upper limits
  73. Swift/UVOT observations of GRB100522A.
  74. GRB 100522A: Enhanced Swift-XRT position
  75. GRB 100522A: NIR observations from CAHA
  76. GRB 100522A: Swift detection of a burst
  77. GRB 100418A: CrAO optical observations
  78. GRB 100518A: GROND afterglow observation and photo-z
  79. GRB 100518A: Swift/UVOT Upper Limits
  80. GRB 100518A: Swift-XRT refined analysis
  81. GRB 100518A: BOOTES-3 optical observations
  82. Update to the configuration of the Fermi-LAT onboard GRB search
  83. GRB 100518A: Swift target of opportunity observation of the INTEGRAL burst
  84. GRB 100513A: MITSuME Akeno Optical Observation
  85. Swift Trigger 422437 is probably not a GRB
  86. GRB 100517A: MASTER-Net wide field camera prompt optical observations
  87. GRB 100513A: EVLA radio observation
  88. GRB 100514A: optical afterglow confirmation
  89. GRB 100514A: Swift/UVOT Observations
  90. GRB 100514A: YNAO-GMG observations
  91. GRB 100514A: Swift XRT refined analysis
  92. GRB 100514A: Enhanced Swift-XRT position
  93. GRB 100514A: Swift detection of a burst
  94. GRB 100513A: Swift/UVOT upper limits
  95. GRB 100513A, RIMOTS optical upper limits
  96. GRB 100513A: Enhanced Swift-XRT position
  97. GRB 100513A: SARA-N Upper Limit
  98. GRB 100513A: Swift detection of a burst
  99. GRB 100511A: Fermi GBM detection/observation
  100. GRB 100511A: Super-LOTIS early observations

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