Skip to main content
JSON Notices via Email, Kafka Cron Jobs, Submitter Profile, GCN is Hiring. See news and announcements

GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

36135 results found.

  1. GRB 011211: Optical Spectroscopy
  2. GRB 011211, Optical Observations
  3. GRB011212, BVRI field photometry
  4. GRB011211, BVRI field photometry
  5. GRB011212: Optical observations
  6. GRB 011211: BVRi-band photometry
  7. GRB011212 (=H10001): An X-Ray Rich GRB Detected by HETE
  8. Fading of the optical source associated of XRF 011211
  9. GRB 011211 Optical Observations: Likely Afterglow
  10. BeppoSAX Alert: GRB011211(=XRF011211)
  11. GRB 011130: Optical Observations of Chandra Sources
  12. GRB 011130: Optical Observations of Chandra sources
  13. GRB 011130: Magellan spectroscopy
  14. Sub-mm and Centimeter Detections of the Host Galaxy of GRB000418
  15. GRB011130, optical observations
  16. GRB 011130, K band observations
  17. GRB011130, optical observations
  18. GRB 011130 I-band Observation
  19. GRB011130 (XRF011130) optical observations
  20. GRB011130 (XRF011130) SDSS PT i-band observations
  21. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  22. XRF011130: NEAT Optical Observations
  23. GRB011130 (=XRF011130): Revised Localization of an X-ray
  24. GRB001109, Radio Monitoring
  25. GRB 011121: Errata URL
  26. GRB 011121
  27. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  28. GRB 011121: J-band observations
  29. GRB 011121: NIR observations, host galaxy?
  30. GRB 011121: HST Scheduled
  31. GRB011121: fainter still
  32. Correction: GCN1157 (GRB 011121)
  33. GRB 011121: Radio Observations
  34. GRB 011121 J-Band Astrometry
  35. GRB011121: continued decay
  36. GRB 011121: Detection of Bright IR Counterpart
  37. GRB011121: possible redshift, continued decay
  38. IPN triangulation of GRB011121
  39. BEPPOSAX GRB011121
  40. GRB 011030: TNG K-band observation
  41. XRF011030: Chandra Observations
  42. GRB 011030: K-band observations
  43. GRB 011030 R band observations
  44. GRB 011030 I-band Observation
  45. The X-ray Flash 011030 ('GRB 011030')
  46. Non-triggered burst 011030 ("GRB 011030")
  47. The Radio Afterglow from the X-ray Rich GRB 011030
  48. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  49. GRB 970828: HST Observations of the Host Galaxy
  50. GRB 000131: HST Detection of the Host Galaxy
  51. GRB 970828: HST Observations of the Host Galaxy
  52. GRB010921, optical observation
  53. GRB 011019 optical observation
  54. GRB011019: Subaru Optical Observations
  55. GRB 011030 I-band Observations
  56. GRB 011030 K-band Observations
  57. GRB010921, optical observations
  58. GRB 011030, WSRT radio observations
  59. GRB011030 - further refinement WFC position
  60. GRB 011030, Radio observations
  61. GRB 011030, R-band observations
  62. BeppoSAX ALERT: Possible X-ray rich GRB011030
  63. GRB 010921: Possible supernova component
  64. GRB011019: NEAT Optical Observations
  65. GRB010921, optical observation at early time
  66. GRB 010921, I-band observations
  67. GRB011019: Optical observations
  68. GRB011019, optical observations
  69. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  70. GRB010921: Spectroscopy of the Host Galaxy
  71. GRB 010921: The afterglow of HETE #1761
  72. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  73. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  74. GRB010923 as seen by BeppoSAX GRBM
  75. GRB010928(=H1770): Localization of a Long GRB by HETE
  76. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  77. GRB010921, negative optical observations
  78. GRB010921 field photometry
  79. GRB010921 Optical Observations
  80. GRB 010921 DPOSS Images Available
  81. IPN triangulation of GRB010921 (=H1761)
  82. H1761: A Bright GRB Detected by HETE
  83. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid
  84. HETE Trigger #1760 (GRB 010920B?): a new optical source
  85. HETE Trigger #1759 (GRB 010920?) optical observations
  86. GRB001109, Host Galaxy Astrometry
  87. GRB000926, Host Galaxy Observations
  88. GRB001109, Host Galaxy Spectroscopic Observations
  89. Probable SGR or Short Duration GRB Detected by HETE
  90. GRB000926 Host Galaxy Observations
  91. GRB 010222: HST observations -- host galaxy and late-time decay
  92. BeppoSAX/GRBM detection of GRB 010801
  93. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  94. GRB 010222 - WHT BVRI images
  95. GRB 010629 Optical Observations
  96. GRB010629: Optical Observations
  97. GRB010629, optical observations
  98. IPN triangulation of GRB010629
  99. GRB010629: A Burst Localized by HETE
  100. Possible burst from SGR1806-20

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