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"

36202 results found.

  1. GRB020305: Properties of the Candidate Optical Afterglow
  2. GRB 011121: HST Observations reveal an intermediate-time multicolor
  3. GRB011121, possible supernova association
  4. GRB011130 (XRF011130) Second Epoch Chandra Observations
  5. GRB020305: Subaru Optical Observations
  6. GRB 020305: Optical observations
  7. XRF/GRB 011030 Images
  8. XRF/GRB 011030: Detection of the Probable Host Galaxy
  9. GRB 020305: Candidate optical afterglow
  10. Type Ic SN2002bl (SN/GRB?) Radio Observations
  11. GRB020305: Optical Observations
  12. IPN triangulation of GRB020305 (HETE 1939)
  13. GRB020305 (=H1939): Localization of a GRB by HETE
  14. GRB 020305: Optical observations
  15. HST Imaging of the afterglow and host of GRB 011121
  16. GRB 010921: HST Observations
  17. IPN detection and localization of Cygnus X-1 flares
  18. GRB020127: Further VLA Observations of Possible Counterparts
  19. IPN detection of further SGR1900+14 activity
  20. SGR1900+14 activity
  21. IPN/HETE Detection of Bursts from SGR1900+14
  22. IPN Upper Limits to a GRB Associated With SN2002ap
  23. GRB020124 BVRI field photometry
  24. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  25. SN2002ap (SN/GRB?) Echelle spectra
  26. SN2002ap (SN/GRB?) optical spectrographic observations
  27. GRB020127 Optical Observations
  28. SN 2002ap (SN/GRB?)
  29. SN2002ap (SN/GRB?) UBVRI Field Photometry
  30. GRB020127: Chandra Observations and Prospective Counterparts
  31. pre-SN2002ap (SN/GRB?) imaging of M74
  32. SN 2002ap (hypernova / GRB ??): special list on VSNET
  33. Type Ib/c SN2002ap (SN/GRB?)
  34. Type Ib/c SN2002ap (SN/GRB?) Radio Observations
  35. GRB020124, optical observations
  36. GRB020127: Optical observations
  37. GRB 020127, I-band observations starting 3.14-hr after the event
  38. IPN detection of further activity from SGR1806-20
  39. IPN triangulation of GRB020127 (=H1902)
  40. GRB010921 Optical Observations
  41. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  42. GRB020124: Optical observations
  43. VLT observations of GRB 020124: The fading optical/near-infrared afterglow
  44. GRB020124: Optical observations
  45. GRB 020124: Optical observations
  46. GRB 020124 Optical Observations
  47. IPN triangulation of GRB020124 (HETE 1896)
  48. IPN observations of SGR1806-20
  49. GRB 020124: Optical afterglow
  50. GRB020124(=H1896): Localization of a Long GRB by HETE
  51. GRB optical counterpart candidate in GCN 1217 is M dwarf
  52. Possible optical counterpart to a GRB
  53. GRB011212, Optical Observations
  54. GRB 011211: Detection of the Probable Host Galaxy
  55. GRB 011130 and GRB 011212 - Milagro GeV/TeV Observations
  56. GRB 011211, spectrum and optical photometry
  57. GRB 011130: Optical Observations of X-ray and Radio Sources
  58. GRB 011130, Radio/X-ray Comparison
  59. GRB 011212: optical observation at Asiago
  60. GRB 011211: Evidence for an Optical Break
  61. GRB 011211: TNG Spectroscopic Observations
  62. optical follow-up of GRB(XRF) 011211
  63. GRB 011212: optical observation at Oslo (relayed)
  64. GRB 011211: Optical Spectroscopy
  65. GRB 011211, Optical Observations
  66. GRB011212, BVRI field photometry
  67. GRB011211, BVRI field photometry
  68. GRB011212: Optical observations
  69. GRB 011211: BVRi-band photometry
  70. GRB011212 (=H10001): An X-Ray Rich GRB Detected by HETE
  71. Fading of the optical source associated of XRF 011211
  72. GRB 011211 Optical Observations: Likely Afterglow
  73. BeppoSAX Alert: GRB011211(=XRF011211)
  74. GRB 011130: Optical Observations of Chandra Sources
  75. GRB 011130: Optical Observations of Chandra sources
  76. GRB 011130: Magellan spectroscopy
  77. Sub-mm and Centimeter Detections of the Host Galaxy of GRB000418
  78. GRB011130, optical observations
  79. GRB 011130, K band observations
  80. GRB011130, optical observations
  81. GRB 011130 I-band Observation
  82. GRB011130 (XRF011130) optical observations
  83. GRB011130 (XRF011130) SDSS PT i-band observations
  84. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  85. XRF011130: NEAT Optical Observations
  86. GRB011130 (=XRF011130): Revised Localization of an X-ray
  87. GRB001109, Radio Monitoring
  88. GRB 011121: Errata URL
  89. GRB 011121
  90. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  91. GRB 011121: J-band observations
  92. GRB 011121: NIR observations, host galaxy?
  93. GRB 011121: HST Scheduled
  94. GRB011121: fainter still
  95. Correction: GCN1157 (GRB 011121)
  96. GRB 011121: Radio Observations
  97. GRB 011121 J-Band Astrometry
  98. GRB011121: continued decay
  99. GRB 011121: Detection of Bright IR Counterpart
  100. GRB011121: possible redshift, continued decay

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