Skip to main content
New! Browse Circulars by Event, Advanced Search, Sample Codes, Schema Release. 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"

2679 results found.

  1. GRB 130907A: MASTER early OT observations
  2. GRB 130907A: Swift detection of a burst with an optical counterpart
  3. GRB 130831A : Xinglong 60cm optical observation
  4. IPN triangulation of GRB 130828A
  5. GRB 130812A: Swift detection of a burst
  6. GRB 130623A: GROND detection of the optical/NIR afterglow
  7. GRB 130702A : Xinglong TNT continue optical observation
  8. GRB 130627B, Swift-BAT refined analysis
  9. GRB 130627B: Possible Swift-XRT afterglow detection
  10. GRB 130623A: Fermi GBM detection
  11. GRB 130625A: Swift detection of a burst
  12. GRB 130623A detected in ground analysis of Swift-BAT data
  13. GRB 130612A: Swift detection of a burst with an optical counterpart
  14. GRB 130608A: ISON-Kislovodsk optical upper limit
  15. GRB 130605A: Swift detection of a burst
  16. GRB 130603B: AMI-LA 15GHz observations
  17. GRB 130603A: SON optical observations
  18. GRB 130603B: Swift detection of a bright short burst
  19. GRB 130528A: Swift detection of a burst
  20. GRB 130514A: Konus-Wind and Swift/BAT joint spectral analysis
  21. GRB 130511A, Swift-BAT refined analysis
  22. GRB 130511A: Enhanced Swift-XRT position
  23. GRB 130511A: Swift detection of a burst with an optical counterpart
  24. GRB 130508A, Swift-BAT refined analysis
  25. GRB 130505B: Swift Candidate Afterglow
  26. GRB 130504A: Bassano Bresciano Observatory optical upper limit
  27. GRB 130427A: MITSuME Ishigakijima Optical Observation after 5 days
  28. GRB 130427B: MITSuME Ishigakijima upper limits
  29. GRB 130427A: Nishi-Harima NIR Observations
  30. GRB 130427A: T100 observations
  31. GRB 130427A: Swift-BAT refined analysis
  32. GRB 130427A: Optical Observations
  33. GRB 130427A: MAXI/GSC detection
  34. GRB 130427A: Swift detection of a very bright burst with a likely bright optical counterpart
  35. GRB 130420A: Redshift from 10.4m GTC
  36. GRB 130327A: Gemini Observations
  37. GRB 130327A: ISON-NM optical upper limit
  38. GRB 130327A: Enhanced Swift-XRT position
  39. GRB 130327A: Swift detection of a burst
  40. GRB 130325A: Fermi GBM detection
  41. GRB 130315A, Swift-BAT refined analysis
  42. GRB 130305A: Gemini-North upper limit
  43. GRB 121128A: optical observations in Mondy observatory
  44. GRB 130211A: Swift-XRT refined Analysis
  45. GRB 130211A: GROND detection of the afterglow
  46. GRB 130206A: GROND Observations
  47. GRB 130102B: MAXI/GSC detection
  48. GRB 121201A: Swift/UVOT Detection
  49. GRB 121201A: a GRB with an optical counterpart
  50. GRB 121108A: MITSuME Ishigakijima upper limits
  51. GRB 121027A - Gemini South spectroscopy
  52. GRB 121011A: MASTER-Net bell light curve
  53. Trigger 535733: Swift possible detection of SAX J1828.5-1037
  54. IPN Triangulation of long GRB 120919B
  55. IPN Triangulation of long GRB 120919A
  56. Swift Trigger 534017 is probably not real.
  57. IPN Triangulation of long GRB 120916A
  58. GRB 120913A: Swift-BAT refined analysis
  59. GRB 120911A: optical upper limit ISON-NM
  60. IPN Triangulation of GRB 120911B (long/bright)
  61. GRB 120908A: MAXI/GSC detection
  62. GRB 120909A: Swift detection of a burst
  63. GRB 120830A: Swift-XRT and UVOT observations
  64. GRB 120817A: FTN and FTS observations
  65. GRB 120817A: Swift detection of a burst
  66. GRB 120811A: Swift/XRT-UVOT Obseravations
  67. Improved IPN error box for short hard GRB 120811B
  68. GRB 120803A: Swift detection of a possible burst
  69. GRB 120802A: MASTER optical observations
  70. Trigger 529076: Swift possible detection of SwJ1910.2-0546
  71. GRB 120724A: FTN optical afterglow candidate
  72. GRB 120712A: Fermi GBM observation
  73. GRB 120712A: Swift detection of a burst with optical afterglow
  74. GRB 120709A: optical afterglow limits
  75. GRB 120703A: NOT optical observation
  76. GRB 120630A: Swift-BAT/-XRT/-UVOT refined analysis
  77. Watcher follow-up observations of IGR J17062-6143 (Swift trigger 525148)
  78. Skynet/PROMPT observations of IGR J17062-6143 (Swift trigger 525148)
  79. Swift detection of IGR J17062-6143
  80. GRB 120622A: MAXI/GSC detection
  81. GRB 120528B: MAXI/GSC detection
  82. GRB 120521C: EVLA Localization of Afterglow
  83. GRB 120521C: Early Tautenburg limits
  84. GRB 120521A: Swift detection of a short burst
  85. GRB 120510A: MAXI/GSC detection of a burst
  86. GRB 120422A: Additional Gemini observations and Keck/LRIS spectroscopy
  87. GRB 120404A: optical observations in Mondy observatory
  88. GRB 120404A: MITSuME Okayama Optical Observation
  89. Konus-Wind observation of GRB 120323A
  90. GRB 120324A: Liverpool Telescope optical candidate
  91. GRB 120320A , optical observations
  92. IPN Triangulation of GRB 120316A
  93. GRB 120308A: Swift detection of a burst
  94. Konus-Wind observation of GRB 120226A
  95. GRB 120215A: MITSuME Okayama Optical upper limits
  96. Skynet/PROMPT observations of GRB120215A
  97. GRB 120212A: MITSuME Ishigakijima Optical Observation
  98. GRB 120211A: Swift-BAT refined analysis
  99. GRB 120119A: GRT detection of early afterglow
  100. GRB 120121A: Swift detection of a burst

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