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"

27475 results found.

  1. GRB 080409: REM optical/NIR observations
  2. GRB 080409: Swift detection of a burst
  3. GRB 080319B: HST observations
  4. GRB 080330: RAPTOR detection of prompt optical flash
  5. GRB 080319B: Potential Jet Break Observed by Swift-XRT and UVOT
  6. GRB 080405: Swift-XRT position
  7. GRB 080405: Mars Oddysey and Swift-BAT detection, possible host galaxy
  8. GRB 080325: optical upper limit
  9. GRB080330: Improved Swift XRT Position
  10. GRB 080330: Prompt PROMPT Observations
  11. GRB080330: optical observations
  12. GRB080330: optical observations
  13. GRB080330: Swift XRT refined analysis
  14. GRB 080330: REM optical observations
  15. GRB 080330, SMARTS optical/IR afterglow observations
  16. GRB080330: TNT optical observations
  17. GRB 080330: Redshift Confirmation from Hobby-Eberly Telescope Spectroscopy
  18. GRB080330: LOAO R-band Detection
  19. GRB 080330: GROND Observations
  20. GRB 080330: NOT redshift
  21. GRB 080330: TAROT Calern observatory optical observations
  22. GRB 080330A: PAIRITEL Infrared Detections
  23. GRB 080330: error in reported XRT position
  24. GRB 080330: Liverpool Telescope Optical observations
  25. GRB 080330A: ROTSE-III Detection of Optical Counterpart
  26. GRB 080330: Swift detection of a burst with an optical counterpart
  27. GRB 080330: TAROT Calern observatory optical detection
  28. GRB 080319B: Continued Gemini-South followup and possible host galaxy
  29. GRB 080328: BTA optical imaging and spectroscopy
  30. GRB 080328: Swift XRT refined analysis
  31. Swift/UVOT observations of GRB080328
  32. GRB080325 - I and z-band Imaging
  33. GRB 080328: Enhanced Swift-XRT position
  34. GRB080328: Faulkes Telescope North observations
  35. GRB 080328: Swift detection of a burst with an optical counterpart
  36. GRB 080325: Subaru detection of NIR afterglow candidate
  37. GRB080310, late-time photometry with LBT
  38. GRB 080325: MITSuME Akeno optical upper limits
  39. GRB080325: XRT Refined Analysis
  40. GRB 080325: GROND Observations
  41. GRB080319B: optical observations
  42. GRB 080325: Swift/UVOT Upper Limits
  43. GRB 080319C: Gemini-North spectroscopic redshift
  44. GRB 080325: Early observations from OSN
  45. GRB 080325: NIR afterglow candidate
  46. GRB 080319D: GROND Detection of the Optical Counterpart
  47. GRB 080325: Enhanced Swift-XRT position
  48. GRB 080325: Swift detection of a burst
  49. GRB 080319B : Apparent spectral evolution in very early Swift/XRT WT mode data: intrinsic or pile-up effect?
  50. GRB 080319B: Spitzer Mid-infrared Observations
  51. GRB 080319B: Second & Third Epoch WSRT Radio Observations
  52. Radio Detection of GRB 080319B
  53. GRB 080319B: Optical observation (Brno, CZ)
  54. GRB 080319D: GROND Observations
  55. GRB 080319B: optical upper limit
  56. GRB 080319D: optical upper limit
  57. GRB080319B: Time-Independent XRT Spectrum
  58. GRB 080319C: UVOT Observations
  59. GRB 080319B: UVOT Observations
  60. GRB 080319A: UVOT Observations
  61. GRB 080320: Swift XRT refined analysis
  62. GRB 080319B - CARMA mm Observations
  63. GRB 080320: Early Super-LOTIS Observations
  64. GRB 080320: J detection with FLAMINGOS
  65. GRB 080319D: Swift XRT refined analysis
  66. GRB 080320: optical limit
  67. GRB 080320: Gemini-N optical afterglow
  68. GRB 080319B: Gemini-South photometry
  69. GRB 080319B: Allen Telescope Array Observations
  70. GRB 080319B optical observations
  71. GRB 080319B: WSRT Radio Observations
  72. GRB 080320: SDSS source and Gemini-N observations
  73. GRB 080320: Enhanced Swift-XRT position
  74. GRB 080320: optical limit from IAC80
  75. GRB 080319C: KAIT OA observations
  76. GRB 080320: Swift detection of a burst
  77. GRB 080320: ROTSE-III Optical Limits
  78. GRB 080319B : Lulin observation of temporal break at 0.2 days
  79. GRB 080319B: RAPTOR observations of a naked eye burst
  80. GRB 080319A: Swift-XRT Team Refined Analysis
  81. GRB080319B: Prompt PROMPT Detections
  82. GRB 080319C: Swift-XRT Team Refined Analysis
  83. GRB 080319B: Swift-XRT Team Refined Analysis
  84. GRB 080319D: Swift/UVOT Refined Analysis of the Fading Optical Afterglow Candidate
  85. GRB 080319C: AGILE-MCAL observation of the prompt emission
  86. GRB 080319B: Hobby-Eberly Telescope Spectroscopy
  87. GRB 080319D: Swift detection of a burst with a possible optical afterglow
  88. GRB 080319B: TORTORA synchronous observation
  89. VLT/UVES redshift of GRB 080319B from FeII fine-structure lines
  90. GRB 080319B: Enhanced Swift-XRT position
  91. GRB 080319A: Enhanced Swift-XRT position
  92. VLT/UVES redshift of GRB 080319B
  93. GRB 080319C: Early Super-LOTIS Observations
  94. GRB 080319C: Swift detection of a burst with an optical afterglow
  95. GRB 080319C: KAIT OA candidate
  96. GRB 080319A: REM observations
  97. GRB 080319b prompt optical observation by Pi-of-the-Sky
  98. GRB 080319B: Gemini-South Spectroscopy
  99. GRB 080319A: optical observations at the NOT
  100. GRB0 080319B : LOAO optical observation

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