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"

10761 results found.

  1. GRB 010214, Optical Observations
  2. J-Band Observation of GRB 010214.
  3. Possible InfraRed Transient of GRB 010214.
  4. GRB010214 Optical Observation
  5. GRB 010214, optical observations
  6. HETE Status
  7. GRB010126 opt. obs.
  8. IPN/RXTE TRIANGULATION OF GRB010126
  9. GRB010126 optical observations
  10. IPN/RXTE TRIANGULATION OF GRB010126
  11. IPN TRIANGULATION OF GRB010115
  12. IPN triangulation of GRB001219
  13. GRB 001212 optical observation
  14. IPN triangulation of GRB001120
  15. GRB 001109 X-ray afterglow with BeppoSAX
  16. GRB001109: Optical observations
  17. GRB001109: BeppoSAX/NFI Observations
  18. XMM-Newton observation of GRB001025
  19. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  20. CORRECTION TO IPN/RXTE ERROR BOX FOR GRB001025
  21. ASM Localization of GRB 001025
  22. GRB001018, Gamma Ray Observations
  23. IPN TRIANGULATION OF GRB001019
  24. GRB 000926 Chandra Observation
  25. IPN triangulation of GRB 001004
  26. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  27. GRB000926 K'-band Observation
  28. IPN triangulation of GRB000925
  29. IPN triangulation of GRB000910
  30. IPN triangulation of GRB000830
  31. HST/STIS observations of the host galaxy of GRB 980329
  32. SGR 1806-20 burst activity
  33. GRB000801 & GRB000730, Gamma Ray Observations
  34. GRB000730, Gamma Ray Observations
  35. GRB000801, Gamma Ray Observations
  36. possible optical counterpart of GRB 000630
  37. IPN triangulation of GRB000630
  38. GRB 000623, optical observations
  39. GRB000620, optical observations
  40. GRB000620: BeppoSAX WFC and GRBM detection
  41. BeppoSAX ALERT: GRB000620
  42. GRB000620: BeppoSAX Alert
  43. GRB000616 [IPN Position]
  44. GRB000615B [IPN Position]
  45. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  46. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  47. GRB000519: Optical observations
  48. IPN triangulation of GRB000516
  49. GRB 000429, optical observation
  50. GRB 000418, UBVRI field photometry
  51. GRB 000418, Optical Observation
  52. GRB 000418, optical observation
  53. GRB 000418, Optical Observation
  54. GRB 000418, Optical Observation
  55. GRB000418, near-infrared observations
  56. IPN error box for GRB000418
  57. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  58. GRB 000408, optical observations
  59. GRB000313, Radio observations
  60. GRB000301C - B and R photometry
  61. GRB 000307, BVRI Field Photometry
  62. IPN error box for GRB000307
  63. GRB 000301C, UBVRI field photometry
  64. GRB 000301C, Optical Observation
  65. GRB 000301A, Radio Observations
  66. GRB 000301C : Optical Candidate
  67. GRB000226 [IPN Position]
  68. GRB 000115 Optical observations
  69. BATSE GRB trigger criterion changed
  70. GRB 000210: BATSE Observations
  71. GRB000210: BeppoSAX GRBM and WFC Detection
  72. GRB000201 Optical Observations
  73. BATSE Observations of GRB000115
  74. GCN resumes full operations
  75. Chandra observation of the X-ray afterglow of GRB991216
  76. GRB 991216 Optical spectroscopy/imaging
  77. GRB 991216 Optical Observation
  78. GRB 991216: Extremely bright BATSE burst
  79. IPN localization of GRB991208
  80. GRB 991105: BATSE Observations
  81. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  82. GRB 990915 optical observations
  83. BATSE GRB trigger criteria
  84. GRB990907: BeppoSAX follow up and X-ray afterglow
  85. GRB990806: BATSE Observations
  86. GRB 990705, R-band observations
  87. Infrared and Optical Observations of GRB990705
  88. GRB990704
  89. Refined BeppoSAX-WFC position of GRB990704
  90. GRB990704: BeppoSAX detection
  91. IPN error box for GRB990527
  92. Late Afterglows of GRBs 990510, 990123
  93. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  94. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  95. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  96. BeppoSAX: A new fast X-ray transient
  97. VLT spectrum of GRB990510
  98. GRB 990510: BATSE Observations
  99. GRB990510
  100. GRB 990506: BATSE Observations

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