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"

36681 results found.

  1. GRB020127: Further VLA Observations of Possible Counterparts
  2. IPN detection of further SGR1900+14 activity
  3. SGR1900+14 activity
  4. IPN/HETE Detection of Bursts from SGR1900+14
  5. IPN Upper Limits to a GRB Associated With SN2002ap
  6. GRB020124 BVRI field photometry
  7. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  8. SN2002ap (SN/GRB?) Echelle spectra
  9. SN2002ap (SN/GRB?) optical spectrographic observations
  10. GRB020127 Optical Observations
  11. SN 2002ap (SN/GRB?)
  12. SN2002ap (SN/GRB?) UBVRI Field Photometry
  13. GRB020127: Chandra Observations and Prospective Counterparts
  14. pre-SN2002ap (SN/GRB?) imaging of M74
  15. SN 2002ap (hypernova / GRB ??): special list on VSNET
  16. Type Ib/c SN2002ap (SN/GRB?)
  17. Type Ib/c SN2002ap (SN/GRB?) Radio Observations
  18. GRB020124, optical observations
  19. GRB020127: Optical observations
  20. GRB 020127, I-band observations starting 3.14-hr after the event
  21. IPN detection of further activity from SGR1806-20
  22. IPN triangulation of GRB020127 (=H1902)
  23. GRB010921 Optical Observations
  24. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  25. GRB020124: Optical observations
  26. VLT observations of GRB 020124: The fading optical/near-infrared afterglow
  27. GRB020124: Optical observations
  28. GRB 020124: Optical observations
  29. GRB 020124 Optical Observations
  30. IPN triangulation of GRB020124 (HETE 1896)
  31. IPN observations of SGR1806-20
  32. GRB 020124: Optical afterglow
  33. GRB020124(=H1896): Localization of a Long GRB by HETE
  34. GRB optical counterpart candidate in GCN 1217 is M dwarf
  35. Possible optical counterpart to a GRB
  36. GRB011212, Optical Observations
  37. GRB 011211: Detection of the Probable Host Galaxy
  38. GRB 011130 and GRB 011212 - Milagro GeV/TeV Observations
  39. GRB 011211, spectrum and optical photometry
  40. GRB 011130: Optical Observations of X-ray and Radio Sources
  41. GRB 011130, Radio/X-ray Comparison
  42. GRB 011212: optical observation at Asiago
  43. GRB 011211: Evidence for an Optical Break
  44. GRB 011211: TNG Spectroscopic Observations
  45. optical follow-up of GRB(XRF) 011211
  46. GRB 011212: optical observation at Oslo (relayed)
  47. GRB 011211: Optical Spectroscopy
  48. GRB 011211, Optical Observations
  49. GRB011212, BVRI field photometry
  50. GRB011211, BVRI field photometry
  51. GRB011212: Optical observations
  52. GRB 011211: BVRi-band photometry
  53. GRB011212 (=H10001): An X-Ray Rich GRB Detected by HETE
  54. Fading of the optical source associated of XRF 011211
  55. GRB 011211 Optical Observations: Likely Afterglow
  56. BeppoSAX Alert: GRB011211(=XRF011211)
  57. GRB 011130: Optical Observations of Chandra Sources
  58. GRB 011130: Optical Observations of Chandra sources
  59. GRB 011130: Magellan spectroscopy
  60. Sub-mm and Centimeter Detections of the Host Galaxy of GRB000418
  61. GRB011130, optical observations
  62. GRB 011130, K band observations
  63. GRB011130, optical observations
  64. GRB 011130 I-band Observation
  65. GRB011130 (XRF011130) optical observations
  66. GRB011130 (XRF011130) SDSS PT i-band observations
  67. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  68. XRF011130: NEAT Optical Observations
  69. GRB011130 (=XRF011130): Revised Localization of an X-ray
  70. GRB001109, Radio Monitoring
  71. GRB 011121: Errata URL
  72. GRB 011121
  73. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  74. GRB 011121: J-band observations
  75. GRB 011121: NIR observations, host galaxy?
  76. GRB 011121: HST Scheduled
  77. GRB011121: fainter still
  78. Correction: GCN1157 (GRB 011121)
  79. GRB 011121: Radio Observations
  80. GRB 011121 J-Band Astrometry
  81. GRB011121: continued decay
  82. GRB 011121: Detection of Bright IR Counterpart
  83. GRB011121: possible redshift, continued decay
  84. IPN triangulation of GRB011121
  85. BEPPOSAX GRB011121
  86. GRB 011030: TNG K-band observation
  87. XRF011030: Chandra Observations
  88. GRB 011030: K-band observations
  89. GRB 011030 R band observations
  90. GRB 011030 I-band Observation
  91. The X-ray Flash 011030 ('GRB 011030')
  92. Non-triggered burst 011030 ("GRB 011030")
  93. The Radio Afterglow from the X-ray Rich GRB 011030
  94. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  95. GRB 970828: HST Observations of the Host Galaxy
  96. GRB 000131: HST Detection of the Host Galaxy
  97. GRB 970828: HST Observations of the Host Galaxy
  98. GRB010921, optical observation
  99. GRB 011019 optical observation
  100. GRB011019: Subaru Optical 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