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"

19549 results found.

  1. GRB010921 field photometry
  2. H1761: A Bright GRB Detected by HETE
  3. GRB000926, Host Galaxy Observations
  4. GRB001109, Host Galaxy Spectroscopic Observations
  5. Probable SGR or Short Duration GRB Detected by HETE
  6. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  7. BeppoSAX/GRBM detection of GRB010728
  8. GRB 010222 - WHT BVRI images
  9. GRB 010629 Optical Observations
  10. SGR1900+14: High Fluence Burst Localized by HETE
  11. GRB010629, optical observations
  12. GRB010629: A Burst Localized by HETE
  13. SGR1900+14: Second Burst Localized by HETE
  14. SGR1900+14: A Burst Localized by HETE
  15. SGR1806-20: A Second, Intense Burst Localized by HETE
  16. SGR1806-20: Localization by HETE
  17. HETE Fully-Automated GCN Notices
  18. GRB000301C: Late-time HST/STIS observation
  19. GRB010518: a faint BeppoSAX detection
  20. GRB000418: HST/STIS Second-epoch Observations
  21. X-ray precursors to the large flare from SGR 1900+14
  22. GRB010427, Gamma Ray Observations
  23. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  24. Millimeter observation of SGR 1900+14
  25. SGR1900+14, I-band observations
  26. GRB010412, field photometry
  27. Giant flare from SGR1900+14
  28. GRB 010326b Optical Observations
  29. GRB010412: BeppoSAX GRBM and WFC observations
  30. GRB010324, revised field photometry
  31. GRB 980326: Late-time HST/STIS observations
  32. GRB010324, field photometry
  33. GRB010326B, field photometry
  34. GRB010326, field photometry
  35. GRB010220, field photometry
  36. Further Optical Observations of GRB 010324
  37. GRB010222, CXO X-ray observations
  38. GRB010324: BeppoSAX/GRBM data
  39. GRB010324, optical observations
  40. GRB010326B: Localization by HETE (2nd GRB for this date)
  41. GRB 010326 optical observations
  42. GRB010326: Refined Localization by HETE
  43. GRB010326: Localization by HETE
  44. Optical Observations of GRB 010324
  45. IPN TRIANGULATION OF GRB010324
  46. GRB010222, late-time optical observation
  47. Support extension to the BeppoSAX mission
  48. GRB 010222, Optical Observations
  49. GRB010220 optical obsercations
  50. GRB010222 - Optical observation
  51. GRB010222 further R-band photometry
  52. GRB 010222: Keck Spectroscopy
  53. GRB010214, field photometry
  54. GRB010222, field photometry
  55. GRB010222 further R-band photometry
  56. GRB 010222 Kyoto optical observation
  57. GRB010222 R-BAND OBSERVATION
  58. GRB010214 follow-up from Hanle
  59. GRB 010222: Near-IR Observations
  60. GRB 010222: Optical Observations
  61. GRB 010222, Decay Slope Confirmed
  62. GRB010222, radio observations
  63. GRB010222, optical observations
  64. GRB 010220, simultaneous optical observations
  65. GRB010220: BeppoSAX WFC and GRBM preliminary data
  66. GRB010214, optical observations
  67. GRB010214: BeppoSAX WFC and GRBM preliminary data
  68. GRB 010214: X-Ray afterglow
  69. GRB 010214 optical observation
  70. J-Band Observation of GRB 010214.
  71. GRB010214, optical observations
  72. GRB010213, optical observations
  73. GRB010213, Near-IR observations
  74. Possible InfraRed Transient of GRB 010214.
  75. GRB010214 Optical Observation
  76. GRB010213 detected by HETE
  77. HETE Status
  78. Optical Observations of GRB 001018 at Keck
  79. Optical observations of GRB 001018 with JCAM
  80. IPN TRIANGULATION OF GRB010109
  81. IPN triangulation of GRB010104
  82. IPN triangulation of GRB010103
  83. IPN triangulation of GRB001219
  84. GRB 001212 Optical Observation
  85. GRB 001212 Optical Observation
  86. GRB001120, optical observations
  87. GRB 001109: deep JHK upper limits
  88. GRB 001109 X-ray afterglow with BeppoSAX
  89. CORRECTION to XMM-Newton observation of GRB001025
  90. GRB001109, Radio observations
  91. GRB001105 BVRI field photometry correction
  92. GRB001105, BVRI field photometry
  93. GRB 001025B, Optical obervations
  94. GRB 991208: HST Imaging of the Host Galaxy
  95. GRB 001025B, I-band observations
  96. GRB 001025A, optical observation
  97. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  98. GRB001007: Optical observations
  99. GRB001007, Radio observations
  100. IPN TRIANGULATION OF GRB001020

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