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"

37549 results found.

  1. GRB 131018B: Fermi GBM observation
  2. GRB 131018A: RATIR Optical and NIR Observations
  3. GRB 131018A: Swift/UVOT Upper Limits
  4. GRB 131018B: Fermi-LAT detection of a burst
  5. GRB 131018A: Swift-XRT refined Analysis
  6. GRB 131018A: KAIT Optical Upper Limit
  7. GRB 131018A, Swift-BAT refined analysis
  8. GRB 131018A: P60 Observations
  9. GRB 131018A: Enhanced Swift-XRT position
  10. GRB 131014A: XRT position information
  11. GRB131018A, optical observations
  12. GRB 131018A: Swift detection of a burst
  13. GRB 131014A: Suzaku WAM observation of the prompt emission
  14. GRB 131014A: GROND observations
  15. GRB 131014A: RATIR Optical/NIR Afterglow Confirmation
  16. Fermi GBM data availability during U.S. government shutdown
  17. GRB 131014A: Swift-XRT refined Analysis
  18. GRB 131011A: Swift/UVOT Upper Limits
  19. GRB 131014A: Swift/UVOT Upper Limits
  20. Fermi 403206457 / GRB 131011A: AAO optical observations
  21. GRB 131014A: RATIR Optical and NIR Observations
  22. GRB 131014A: Enhanced XRT position
  23. Konus-Wind observation of GRB 131014A
  24. GRB 131014A: NOT afterglow candidate
  25. GRB 131014A: Nanshan optical observations
  26. GRB 131014A: Swift detection of a possible X-ray afterglow
  27. GRB 131014A Tiled Swift observations
  28. GRB 131014A: Fermi-LAT detection
  29. GRB 131014A: Fermi GBM detection
  30. GRB 131011A: Fermi GBM detection
  31. iPTF 13dsw/Fermi403206457: X-Shooter redshift
  32. Swift-XRT detection of iPTF 13dsw/Fermi403206457
  33. GRB 131011A: GROND afterglow observations
  34. Fermi403206457: continued P60 observations and fading behavior
  35. Fermi403206457: Weihai optical upper limit
  36. Fermi403206457: NOT optical observations
  37. Fermi403206457: iPTF detection of a possible optical afterglow
  38. Trigger 574266 is not a Swift detection of a known source
  39. GRB 130925A: Possible signatures of binary nature in the afterglow - Request for observations
  40. GRB 130831A: Continued RATIR Optical and NIR Observations
  41. GRB 130831A: VLT/FORS2 spectroscopic detection of a supernova
  42. GRB 131004A: MOSFIRE NIR imaging
  43. GRB 131004A: Correction to XRT refined analysis
  44. GRB 131004A: Skynet PROMPT/DSO-14 upper limits
  45. GRB 131004A, Swift-BAT refined analysis
  46. GRB 131004A: Fermi GBM observation
  47. GRB 131004A: CARMA 93 GHz upper limit
  48. GRB 131004A: Swift/UVOT Detection
  49. GRB 131004A: RATIR Optical and NIR Upper Limits
  50. GRB 131004A: Swift-XRT refined Analysis
  51. GRB131004A: TNG Redshift confirmation
  52. GRB 131004A: GROND observations of the afterglow
  53. GRB 131004A: Enhanced Swift-XRT position
  54. GRB131004A: Magellan Redshift
  55. GRB 131004A: Liverpool Telescope optical afterglow observations
  56. GRB 131004A: TNG optical afterglow confirmation
  57. GRB 131004A: optical afterglow from the NOT
  58. GRB 131004A: Swift detection of a burst (may be short)
  59. GRB 131002A, Swift-BAT refined analysis
  60. GRB 130925A: 3mm observations with CARMA
  61. GRB 131002A: Fermi GBM observation
  62. GRB 130925A/Sw J0244-2609: mm observations at PdBI
  63. GRB 131002B, Swift-BAT refined analysis
  64. GRB 131002B: GROND upper limits
  65. GRB 131002B: Swift-XRT Refined Analysis
  66. GRB 131002B: Swift/UVOT Upper Limits
  67. GRB 131002A: Swift/UVOT Detection
  68. GRB 131001A, Swift-BAT refined analysis
  69. GRB 131002A: Swift-XRT refined Analysis
  70. GRB 131002B: Enhanced Swift-XRT position
  71. GRB 131002A: ISON-NM optical observations
  72. Swift J1242.9-3530, Swift-BAT refined analysis
  73. GRB 131001A: Swift UVOT and XRT Upper Limits
  74. GRB 131002A: Enhanced Swift-XRT position
  75. NuSTAR observations of GRB 130925A
  76. Fermi Gamma-ray Burst Monitor trigger 402405063 / 131002466 is not a GRB
  77. GRB 131002B: Swift detection of a burst
  78. GRB 131002A: Swift detection of a burst
  79. GRB 131002A: Faulkes Telescope North optical afterglow
  80. GRB 131001A detected in ground analysis of Swift-BAT data
  81. GRB 130925A: continuing Swift/XRT monitoring
  82. Swift Operations in the event of a US Government shutdown
  83. IPN Observations of GRB 130925A
  84. US Government shutdown may impact GRB operation of GCN
  85. GRB 130930A: Swift detection of a burst
  86. GRB 130929A: Swift/UVOT Upper Limits
  87. GRB 130831A: Continued RATIR Optical and NIR Observations
  88. GRB 130929A: Swift-XRT refined Analysis
  89. GRB 130929A, Swift-BAT refined analysis
  90. GRB 130929A: Enhanced Swift-XRT position
  91. GRB 130929A: TAROT La Silla observatory optical observations
  92. GRB 130929A: Swift detection of a burst
  93. Fermi LAT Upper Limits on GRB 130925A
  94. GRB 130925A: Swift/UVOT Detection of the Host Galaxy
  95. GRB 130925A: Swift/UVOT Upper Limits
  96. GRB 130925A: sub-mm non-detection with SMA
  97. GRB 130925A: optical upper limit
  98. GRB 130925A: Continued RATIR Optical and NIR Observations
  99. GRB 130925A: Fermi GBM Detection
  100. Konus-Wind observation of GRB 130925A

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