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"

26499 results found.

  1. GRB070506: Swift/UVOT Observations
  2. GRB070506: Swift XRT refined analysis
  3. GRB 070506, Swift-BAT Refined Analysis
  4. GRB 070506: Swift detection of a burst with optical afterglow
  5. GRB 070429A: Swift XRT further analysis
  6. GRB070429B: VLT observations
  7. GRB070429B: position correction
  8. GRB 070309: Swift-XRT afterglow confirmation
  9. VLA observation of GRB 070429B
  10. Swift/UVOT observations of GRB070429B
  11. Swift/UVOT observations of GRB070429A
  12. GRB 070429A: Swift XRT refined analysis
  13. GRB 070429A: optical and NIR observations
  14. GRB 070429B: Swift XRT refined analysis
  15. GRB 070429B: ROTSE-III Optical Limits
  16. GRB 070429: ROTSE-III Optical Limits
  17. GRB 070429: Swift detection of a burst
  18. GRB 070427, Swift-BAT Refined Analysis
  19. LT monitoring of GRB070412
  20. GRB 070411: Late-time Keck imaging
  21. GRB070419B: Suzaku WAM observation of the prompt emission
  22. Konus-Wind observation of GRB 070420
  23. GRB 070411: break in the optical light curve
  24. GRB 070420 Swift-BAT Refined Analysis
  25. GRB 070420: Swift XRT refined analysis
  26. GRB070420: Swift UVOT continuing observations
  27. GRB 070420: Faulkes Telescope South Observations
  28. GBR 070419A: Swift/XRT refined analysis
  29. GRB 070420: TAROT La Silla observatory optical observations
  30. GRB 070420: NIR and optical afterglow confirmed
  31. GRB 070420: Swift detection of a burst with optical afterglow
  32. GRB 070419A: MITSuME Okayama Observations
  33. GRB 070419A Swift-BAT Refined Analysis
  34. GRB 070419B: Swift XRT refined analysis
  35. GRB 070419: Keck/LRIS Absorption Redshift
  36. GRB070419 - SDSS Pre-Burst Observations
  37. GRB 070419A: SARA observations
  38. GRB 070419A: NAYUTA Optical Observation
  39. GRB 070419A: Faulkes Telescope North Optical Observations
  40. GRB 070419B optical afterglow candidate
  41. GRB 070419A: Optical and IR observations with KANATA
  42. GRB 070419B: optical afterglow candidate
  43. GRB070419A, optical observation
  44. Infrared detection of GRB070419A with UKIRT
  45. GRB 070419A: Kiso Optical observation
  46. GRB 070419: P60 Confirmation of Optical Afterglow
  47. GRB 070419B: Swift detection of a burst
  48. GRB 070419A: ROTSE-III Optical Limits
  49. GRB 070419: Swift detection of a burst
  50. GRB 070418: Optical and IR observations with KANATA
  51. Trigger 276045: Swift detection of a possible burst
  52. GRB 070406: Swift XRT refined analysis
  53. GRB070412: UKIRT-WFCAM JHK upper limits
  54. GRB070412: Swift UVOT observations
  55. GRB 070411: Swift/UVOT observations
  56. GRB 070412, Swift-BAT refined analysis
  57. GRB 070412 Liverpool Telescope optical limit
  58. GRB 070412: Swift-XRT refined analysis
  59. GRB 070411: Swift-XRT refined analysis
  60. GRB 070412: Optical observations at Crni Vrh
  61. GRB 070411: OA redshift
  62. GRB 070412: further NOT observations
  63. GRB 070412: IAC80 optical afterglow candidate
  64. GRB 070412: NOT observations
  65. GRB 070412: Swift detection of a burst
  66. GRB 070411: IAC80 optical observations
  67. GRB 070411 : Liverpool Telescope Observations
  68. GRB 070411: Swift detection of a burst with optical afterglow
  69. GRB 070406: Swift XRT team further analysis
  70. Suzaku ToO observation of SGR 1806-20
  71. GRB 070406: Astrometrically Refined XRT Position, Unfading Source
  72. GRB 070406: Correction to the optical candidate in GCN6253
  73. GRB 070406: Gemini South Imaging and XRT analysis
  74. GRB070406: Swift UVOT observations
  75. GRB 070406: NOT observations
  76. GRB 070406: SARA upper limit
  77. GRB 070406: Xinglong TNT optical Upper Limit
  78. GRB 070402: Suzaku WAM observation of the prompt emission
  79. Konus-Wind and Konus-A observations of GRB 070402
  80. IPN triangulation of GRB070402
  81. GRB 070328: Suzaku WAM observation of the prompt emission
  82. UVOT observations of GRB070330
  83. GRB 070330: TAROT La Silla observatory optical observations
  84. GRB 070330: Swift-XRT refined analysis
  85. GRB 070330 - Watcher Observations
  86. Konus-Wind observation of GRB 070328
  87. GRB 070328: Swift/UVOT Upper Limits
  88. GRB 070328: Swift/XRT Refined Analysis
  89. GRB 070328 : Suzaku ToO follow up starts
  90. GRB 070328: Swift detection of a burst
  91. GRB 070311, deep optical photometry
  92. Short-Hard GRB 070209: PROMPT Observations
  93. GRB 070318: absorption-line redshift
  94. GRB070318: Swift UVOT continuing observations
  95. GRB070318: Swift-XRT refined analysis
  96. GRB 070318: Swift/UVOT Continued Observations
  97. GRB 070318, Swift-BAT refined analysis
  98. GRB 070318: Swift detection of a burst with an optical afterglow
  99. GRB 070311: Late Central Engine Activity Optical Flare??
  100. GRB 070311: MDM Optical Monitoring

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