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"

32541 results found.

  1. GRB 090531B: Swift/BAT spectral lag results
  2. Corrections to GRB 090531B Swift/UVOT Upper Limits
  3. GRB 090531B, RIMOTS optical upper limits
  4. GRB 090531B: Swift/UVOT Upper Limits
  5. GRB 090528B: MASTER-II Kourovka optical limit
  6. GRB 090529: MITSuME optical observation
  7. GRB 090530: GRT Optical Observation
  8. GRB 090531B: Swift-BAT refined analysis
  9. Initial Swift/UVOT observations of GRB 090531B
  10. GRB 090531B: Swift-XRT candidate afterglow position
  11. GRB 090531B: ROTSE-III Optical Limits
  12. GRB 090531: Swift-BAT refined analysis
  13. GRB090530: R-band Observation
  14. GRB 090530: break in light curve
  15. GRB 090529: VLT spectroscopic redshift
  16. GRB 090531: GROND upper limits
  17. GRB 090531: P60 Observations
  18. GRB 090529: NOT optical observations
  19. GRB 090530: NOT optical observations
  20. GRB090530: Swift XRT refined analysis
  21. GRB090530: Swift/UVOT afterglow detection
  22. GRB 090529: Swift-XRT refined analysis
  23. GRB 090529: OSN optical observations
  24. Strong radio emission from SN 2007bg one year after the explosion - detection of spreading, off-axis GRB jet?
  25. GRB 090530: Swift-BAT refined analysis
  26. GRB 090530: GRAS002 refined OA analysis
  27. GRB 090530: GRAS002 optical observations
  28. GRB 090530: PAIRITEL NIR Detections
  29. GRB 090530A: ROTSE-III Detection of Optical Counterpart
  30. GRB 090529: optical observations
  31. GRB 090529: TLS Afterglow Observations
  32. GRB090529: UVOT/Swift detection of a brightening optical afterglow
  33. GRB 090529: Swift-BAT refined analysis
  34. GRB 090529: Preliminary Swift/UVOT Upper Limit
  35. GRB 090529: Xinglong TNT optical observation
  36. GRB 090520B: Fermi GBM detection
  37. GRB 090518 - NOT upper limit
  38. GRB 090516A: Konus-Wind and Swift/BAT joint spectral analysis
  39. GRB 090520: GROND upper limits
  40. GRB 090518: Fermi GBM detection
  41. GRB 090423: Fermi GBM T90 follow-up analysis results
  42. GRB 090516: Fermi GBM observation
  43. GRB 090519: Swift-XRT refined analysis
  44. GRB 090519: NOT refined analysis
  45. GRB 090519: VLT spectroscopic redshift
  46. GRB 090519: GROND observation
  47. GRB 090519: Swift/UVOT Upper Limits
  48. GRB 090519, Swift-BAT refined analysis
  49. GRB 090519: NOT afterglow candidate
  50. GRB 090518: Swift/UVOT Upper Limits
  51. GRB 090516: Observations from Stardome Observatory
  52. GRB090518: GROND upper limits
  53. GRB 090518: P60 Observations
  54. GRB 090518, Swift-BAT refined analysis
  55. GRB 090516, RIMOTS optical upper limits
  56. GRB090518 : Optical upper limit by MOA-II telescope
  57. GRB 090518: Swift-XRT refined analysis
  58. GRB 090515: Swift/BAT spectral lag results
  59. GRB 090516: Swift-BAT refined analysis
  60. GRB 090516: VLT spectrum (correction & update)
  61. GRB 090516: GROND OBSERVATIONS
  62. GRB 090516: VLT redshift
  63. GRB 090516 - Zadko Telescope observations
  64. GRB 090516: NOT optical observations
  65. GRB 090516: Swift XRT refined analysis
  66. GRB 090516: Swift/UVOT Observations
  67. GRB 090516: Faulkes Telescope South optical afterglow
  68. GRB 090515: Lick Upper Limits
  69. GRB 090515: ROVOR Upper Limit
  70. GRB 090515: MMT/MMIRS NIR Upper Limit
  71. GRB 090515: Swift/UVOT Observations
  72. GRB 090515: Swift-XRT refined analysis
  73. GRB 090509: Fermi GBM observation
  74. GRB 090515: Swift-BAT refined spectral analysis
  75. GRB 090515: Swift-BAT refined analysis
  76. GRB 090509 - Zadko Telescope observations
  77. GRB 090515: Gemini-N upper limit
  78. GRB 090515: WIYN NIR Upper Limit
  79. GRB 090515: Super-LOTIS Upper Limits
  80. GRB 090515: PAIRITEL Upper Limits
  81. GRB 090515: KAIT optical upper limits
  82. GRB 090515: ROTSE-III Optical Limits
  83. GRB 090510: Suzaku WAM observation of the prompt emission
  84. GRB 090510, Radio limits
  85. GRB090510: VLT/FORS2 spectroscopic redshift
  86. GRB 090510: GROND observations
  87. GRB 090510: Swift/UVOT host galaxy candidates
  88. GRB 090510: Fermi-LAT follow-up analysis
  89. GRB 090509, further Swift-BAT refined analysis
  90. GRB 090510: correction to GCN 9344
  91. Konus-Wind observation of GRB 090510
  92. AGILE detection of GRB 090510
  93. GRB 090510: UVOT refined analysis
  94. GRB 090510: Swift XRT refined analysis
  95. GRB 090510: correction to coordinates in GCN 9338
  96. GRB 090510: NOT afterglow confirmation
  97. GRB 090510: Swift-BAT refined analysis
  98. GRB 090510: Fermi GBM detection
  99. GRB 090509: Swift-BAT refined analysis
  100. GRB 090509, SMARTS optical/IR afterglow 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