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"

42554 results found.

  1. GRB010222, CXO X-ray observations
  2. GRB 010326A: Further optical observations
  3. GRB010324: BeppoSAX/GRBM data
  4. GRB 010326B: Optical observations
  5. GRB010324, optical observations
  6. GRB010326B: Localization by HETE (2nd GRB for this date)
  7. GRB 010326: Optical observations
  8. GRB 010326 optical observations
  9. GRB010326: Refined Localization by HETE
  10. GRB010326: Localization by HETE
  11. Duration, ECT, peak flux and fluence of GRB010324
  12. Optical Observations of GRB 010324
  13. IPN TRIANGULATION OF GRB010324
  14. GRB990705, VLT-FORS1 observations of the host galaxy
  15. GRB010222, late-time optical observation
  16. Support extension to the BeppoSAX mission
  17. GRB 010222 - HEGRA GeV/TeV Observations
  18. Congratulate Scott on the 1000th GRB Coordinates Network Circular!
  19. GRB010222: Chandra X-ray Observatory Observation
  20. GRB010222: Sub-millimeter vanishing act
  21. GRB010222 - Optical observation
  22. GRB 010222, Optical Observations
  23. GRB010220 optical obsercations
  24. GRB010222 - Optical observation
  25. GRB 010222: High-Resolution Keck Spectroscopy
  26. GRB010222: Optical observation and decay
  27. GRB 010214, I-band data
  28. Sub-millimeter Excess/GRB 010222
  29. GRB 010222
  30. GRB 010222 HST/Chandra TOO
  31. GRB010222 further R-band photometry
  32. GRB010222: R-band data
  33. GRB010222 Optical observations
  34. GRB 010222: Keck Spectroscopy
  35. GRB010214, field photometry
  36. GRB010222, field photometry
  37. GRB010222 further R-band photometry
  38. GRB010222, possible increase of optical decay slope
  39. GRB 010222 Kyoto optical observation
  40. GRB010222: fading behavior
  41. GRB 010222 BV optical observations
  42. GRB010222 R-BAND OBSERVATION
  43. GRB 010220: Near-IR Observations
  44. GRB 010222: Near-IR Observations
  45. GRB 010222: Optical Observations
  46. GRB 010222, Decay Slope Confirmed
  47. GRB010222: Another absorption line system
  48. GRB010222: Optical decay slope
  49. GRB 010214, Optical Observations
  50. GRB010222: Sub-millimeter detection
  51. GRB010222: R-band fading behavior
  52. GRB010222: Optical Observations
  53. GRB010222, radio observations
  54. GRB010222, optical observations
  55. GRB010222: BeppoSAX/NFI Observations
  56. Redshift of the Optical Transient of GRB010222
  57. GRB010214B,Gamma Ray Observations
  58. GRB010222: possible optical counterpart
  59. GRB010222
  60. GRB010222
  61. GRB010222: BeppoSAX refined position
  62. ALERT: GRB010222: the brightest GRB observed by BeppoSAX
  63. GRB010220, Radio and Optical Observations
  64. GRB 010220, simultaneous optical observations
  65. GRB010220: BeppoSAX WFC and GRBM preliminary data
  66. GRB010214, candidate optical afterglow
  67. GRB010214, optical observations
  68. BeppoSAX ALERT: GRB010220
  69. GRB010214: BeppoSAX WFC and GRBM preliminary data
  70. GRB 010214: X-Ray afterglow
  71. GRB 010214, Optical Observations
  72. GRB010213, Radio Observations
  73. GRB010213 Optical Observation
  74. GRB010213, Radio Observations
  75. J-Band Observation of GRB 010214.
  76. GRB010214, Radio Observations
  77. GRB010214, optical observations
  78. GRB010213, optical observations
  79. GRB010213, Near-IR observations
  80. Possible InfraRed Transient of GRB 010214.
  81. GRB010214 Optical Observation
  82. GRB010214: BeppoSAX/NFI Observations
  83. GRB010213 (HETE) TAROT observations
  84. GRB 010214, optical observations
  85. GRB010213 detected by HETE
  86. BeppoSAX ALERT: GRB010214
  87. IPN Status Report
  88. HETE Status
  89. GRB010126 opt. obs.
  90. IPN/RXTE TRIANGULATION OF GRB010126
  91. GRB010126: CONCAM crude optical limits during GRB
  92. GRB010126, TNG R-band observations
  93. GRB010126 Optical Observations
  94. GRB010126 optical observations
  95. GRB010126: Optical observations
  96. IPN TRIANGULATION OF GRB010126
  97. IPN/RXTE TRIANGULATION OF GRB010126
  98. GRB 010119, optical observations
  99. GRB010119: Optical observations
  100. Optical Observations of GRB 001018 at Keck

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