Skip to main content
New! BOOM Notices and Schema v7.0.0. 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"

41203 results found.

  1. GRB 090618: Lick/KAST Spectroscopy
  2. GRB 090618: OA behavior from KAIT
  3. GRB 090618: planned XMM-Newton observation
  4. GRB 090618: ROTSE-III Detection of Optical Counterpart
  5. GRB 090618: KAIT optical afterglow
  6. GRB090618: P60 Optical Afterglow
  7. GRB 090618: Swift detection of a bright burst with optical afterglow
  8. GRB 090616: Fermi GBM detection
  9. GRB 090612: Fermi GBM detection
  10. GRB 090610C: Fermi GBM detection
  11. GRB 090610B: Fermi GBM detection
  12. GRB 090610: Fermi GBM detection
  13. SGR 0418+5729 Fermi/GBM Detection of Pulsations
  14. GRB 090602: Suzaku WAM observation of the prompt emission
  15. GRB 090424: WSRT Radio Observations
  16. GRB 090423: WSRT Radio Observations
  17. RXTE Discovery of Pulsations from SGR 0418+5729
  18. GRB 090531B: Fermi GBM detection
  19. Konus-RF observation of SGR burst 090605A
  20. Discovery of a new soft gamma repeater source, SGR 0418+5729
  21. GRB 090608: Fermi GBM detection
  22. GRB 090606: Fermi GBM detection
  23. GRB 090607: XRT Team Refined Analysis
  24. GRB 090607: Swift/UVOT Upper Limits
  25. GRB 090607: Swift-BAT refined analysis of the SHB
  26. GRB 090607: GRAS001 optical observations
  27. GRB 090607: Faulkes Telescope North observations
  28. GRB 090607: Swift detection of a burst
  29. Ignore GCN/Swift-BAT Lightcurve Notices for trigger 353567
  30. GRB 090530B: Suzaku WAM observation of the prompt emission
  31. GRB 090530: Further NOT optical observations
  32. GRB 090530: RTT150 Optical Observation
  33. GRB 090602: Fermi GBM detection
  34. GRB 090529A: RTT150 Optical Observations
  35. GRB 090528: Suzaku WAM observation of the prompt emission
  36. GRB090529: Further NOT optical observations
  37. GRB 090531b, SMARTS optical/IR observations
  38. GRB 090531B: GROND observation
  39. GRB 090528B: Suzaku WAM observation of the prompt emission
  40. GRB 090530: Early RAPTOR Optical Observations
  41. GRB090529B: ROVOR Upper Limits
  42. GRB 090531A: SARA upper limit
  43. GRB 090531B: Swift/BAT spectral lag results
  44. GRB 090529C: Fermi GBM detection
  45. GRB 090529B: Fermi GBM detection
  46. GRB 090530B: Fermi GBM detection
  47. GRB 090531B, RIMOTS optical upper limits
  48. GRB 090531B: Swift/UVOT Upper Limits
  49. GRB 090528B: MASTER-II Kourovka optical limit
  50. GRB 090529: MITSuME optical observation
  51. GRB 090530: GRT Optical Observation
  52. GRB 090531B: Swift-BAT refined analysis
  53. Initial Swift/UVOT observations of GRB 090531B
  54. GRB 090531B: Swift-XRT candidate afterglow position
  55. GRB 090531B: ROTSE-III Optical Limits
  56. GRB 090531B: Swift detection of a burst
  57. GRB 090531: Swift-BAT refined analysis
  58. GRB090530: R-band Observation
  59. GRB 090530: break in light curve
  60. GRB 090529: VLT spectroscopic redshift
  61. GRB 090531: GROND upper limits
  62. GRB 090531: P60 Observations
  63. GRB 090531: Swift detection of a burst
  64. GRB 090529: NOT optical observations
  65. GRB 090530: NOT optical observations
  66. GRB090530: Swift XRT refined analysis
  67. GRB090530: Swift/UVOT afterglow detection
  68. GRB 090529: Swift-XRT refined analysis
  69. GRB 090529: OSN optical observations
  70. GRB 090528B: Fermi GBM detection
  71. GRB 090528: Fermi GBM detection
  72. GRB 090530: Enhanced Swift-XRT position
  73. Strong radio emission from SN 2007bg one year after the explosion - detection of spreading, off-axis GRB jet?
  74. GRB 090530: Swift-BAT refined analysis
  75. GRB 090530: GRAS002 refined OA analysis
  76. GRB 090530: GRAS002 optical observations
  77. GRB 090530: PAIRITEL NIR Detections
  78. GRB 090530A: ROTSE-III Detection of Optical Counterpart
  79. GRB 090530: Swift detection of a burst with an optical counterpart
  80. GRB 090529: optical observations
  81. GRB 090529: TLS Afterglow Observations
  82. GRB090529: UVOT/Swift detection of a brightening optical afterglow
  83. GRB 090529: Swift-BAT refined analysis
  84. GRB 090529: Enhanced Swift-XRT position
  85. GRB 090529: Preliminary Swift/UVOT Upper Limit
  86. GRB 090529: Xinglong TNT optical observation
  87. GRB 090529: Swift detection of a burst
  88. GRB 090520D: Fermi GBM detection
  89. GRB 090520C: Fermi GBM detection
  90. GRB 090520B: Fermi GBM detection
  91. GRB090518B optical limit by "Pi of the Sky"
  92. GRB 090522 : Fermi GBM detection
  93. GRB 090524: Fermi GBM detection
  94. GRB 090518 - NOT upper limit
  95. GRB 090516A: Konus-Wind and Swift/BAT joint spectral analysis
  96. GRB 090513B: Fermi GBM detection
  97. GRB 090518: Fermi GBM detection
  98. GRB 090516C: Fermi GBM detection
  99. GRB 090520 Swift-BAT detection of a burst in ground analysis
  100. GRB 090423: Fermi GBM T90 follow-up analysis results

Advanced

Download all Circulars as a .tar.gz archive:
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