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"

35440 results found.

  1. Possible burst from SGR1806-20
  2. IPN detection of SGR1900+14
  3. GRB 00630: Host Galaxy
  4. IPN triangulation of GRB010613
  5. IPN triangulation of GRB010612
  6. HETE Fully-Automated GCN Notices
  7. GRB000301C: Late-time HST/STIS observation
  8. GRB010518: a faint BeppoSAX detection
  9. GRB000418: HST/STIS Second-epoch Observations
  10. GRB010427, Gamma Ray Observations
  11. SGR1900+14
  12. GRB 010222 /corrections to VBT data
  13. Possible precursor to the SGR1900+14 giant burst
  14. IPN Triangulation of the Giant Flare from SGR1900+14
  15. GRB010412, field photometry
  16. GRB 010326b Optical Observations
  17. GRB010412: Optical observations
  18. GRB010412: Optical observations
  19. IPN Triangulation of GRB010412
  20. BeppoSAX GRB: extension of BSAX operations upto April 30, 2002
  21. BeppoSAX GRB ALERT: GRB010412
  22. GRB Observation Report
  23. GRB010324, revised field photometry
  24. REVISED LOCATION OF GRB010326A
  25. GRB 980326: Late-time HST/STIS observations
  26. GRB010324, field photometry
  27. GRB010326B, field photometry
  28. GRB010326, field photometry
  29. GRB010220, field photometry
  30. Further Optical Observations of GRB 010324
  31. GRB 010326A: Further optical observations
  32. GRB010324: BeppoSAX/GRBM data
  33. GRB 010326B: Optical observations
  34. GRB010324, optical observations
  35. GRB010326B: Localization by HETE (2nd GRB for this date)
  36. GRB 010326: Optical observations
  37. GRB 010326 optical observations
  38. GRB010326: Refined Localization by HETE
  39. GRB010326: Localization by HETE
  40. Duration, ECT, peak flux and fluence of GRB010324
  41. Optical Observations of GRB 010324
  42. IPN TRIANGULATION OF GRB010324
  43. GRB990705, VLT-FORS1 observations of the host galaxy
  44. GRB010222, late-time optical observation
  45. Support extension to the BeppoSAX mission
  46. GRB 010222 - HEGRA GeV/TeV Observations
  47. Congratulate Scott on the 1000th GRB Coordinates Network Circular!
  48. GRB010222: Chandra X-ray Observatory Observation
  49. GRB010222: Sub-millimeter vanishing act
  50. GRB 010222, Optical Observations
  51. GRB 010222: High-Resolution Keck Spectroscopy
  52. GRB 010214, I-band data
  53. Sub-millimeter Excess/GRB 010222
  54. GRB 010222
  55. GRB 010222 HST/Chandra TOO
  56. GRB 010222
  57. GRB010222 further R-band photometry
  58. GRB010222: R-band data
  59. GRB010222 Optical observations
  60. GRB 010222: Keck Spectroscopy
  61. GRB010214, field photometry
  62. GRB010222, field photometry
  63. GRB010222 further R-band photometry
  64. GRB010222, possible increase of optical decay slope
  65. GRB 010222 Kyoto optical observation
  66. GRB010222: fading behavior
  67. GRB 010222 BV optical observations
  68. GRB 010220: Near-IR Observations
  69. GRB010214 follow-up from Hanle
  70. GRB 010222: Near-IR Observations
  71. GRB 010222: Optical Observations
  72. GRB 010222, Decay Slope Confirmed
  73. GRB010222: Another absorption line system
  74. GRB010222: Optical decay slope
  75. GRB 010214, Optical Observations
  76. GRB010222: Sub-millimeter detection
  77. GRB010222: R-band fading behavior
  78. GRB010222: Optical Observations
  79. GRB010222, optical observations
  80. GRB010222: BeppoSAX/NFI Observations
  81. Redshift of the Optical Transient of GRB010222
  82. GRB010214B,Gamma Ray Observations
  83. GRB010222
  84. ALERT: GRB010222: the brightest GRB observed by BeppoSAX
  85. GRB 010220, simultaneous optical observations
  86. GRB010220: BeppoSAX WFC and GRBM preliminary data
  87. BeppoSAX ALERT: GRB010220
  88. GRB010214: BeppoSAX WFC and GRBM preliminary data
  89. GRB 010214: X-Ray afterglow
  90. GRB 010214, Optical Observations
  91. GRB 010214 optical observation
  92. GRB010213 Optical Observation
  93. J-Band Observation of GRB 010214.
  94. GRB010213, Near-IR observations
  95. Possible InfraRed Transient of GRB 010214.
  96. GRB010214 Optical Observation
  97. GRB010214: BeppoSAX/NFI Observations
  98. GRB010213 (HETE) TAROT observations
  99. GRB 010214, optical observations
  100. BeppoSAX ALERT: GRB010214

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