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"

15557 results found.

  1. GRB 020331: Candidate Optical Afterglow
  2. GRB 020405: Decay index
  3. GRB020405, Radio Observations
  4. Fading Optical Afterglow and Possible Host Galaxy of GRB 020405
  5. GRB 020405, U-band observations
  6. GRB 020405: Optical afterglow candidate
  7. GRB011212: Optical Observations
  8. GRB 020331 Optical Observations
  9. GRB 020331: Optical observations
  10. GRB020331(=H1963): The "Easter" Burst Detected by HETE
  11. GRB011211: HST Observations of Optical Afterglow and Host Galaxy
  12. GRB 020322, Radio observations
  13. Near-Infrared Observations of GRB020322 at TIRGO
  14. GRB 020322: Optical Observations
  15. GRB 020321: Optical observations
  16. GRB020317 BVRI field photometry
  17. GRB011211 revised BVRI field photometry
  18. GRB020305 BVRI field photometry
  19. GRB020322 BVRI field photometry
  20. GRB 020322 optical observations
  21. GRB020322: Candidate Optical Afterglow
  22. GRB 020322 optical observation
  23. GRB 020322: Optical Sources and Improved Astrometry
  24. GRB020322, optical observations
  25. GRB 020322: Optical candidate
  26. GRB020322: Optical Observations
  27. GRB 020321: Optical observations
  28. GRB020317: optical observations
  29. GRB020321 optical observations
  30. GRB 020317 : KISO Optical Observations
  31. GRB020317 (=H1959): Localization by HETE of a Low Fluence GRB
  32. GRB 020305: Optical Observations
  33. GRB020317, optical observations
  34. GRB 020317: Optical observations
  35. GRB020305: Properties of the Candidate Optical Afterglow
  36. GRB 011121: HST Observations reveal an intermediate-time multicolor
  37. GRB020305: Subaru Optical Observations
  38. GRB 020305: Optical observations
  39. XRF/GRB 011030: Detection of the Probable Host Galaxy
  40. GRB 020305: Candidate optical afterglow
  41. Type Ic SN2002bl (SN/GRB?) Radio Observations
  42. GRB020305, optical observations
  43. GRB020305: Optical Observations
  44. IPN triangulation of GRB020305 (HETE 1939)
  45. GRB020305 (=H1939): Localization of a GRB by HETE
  46. GRB 020305: Optical observations
  47. HST Imaging of the afterglow and host of GRB 011121
  48. GRB020124 BVRI field photometry
  49. GRB020127: Palomar and VLA Observations of Possible Counterparts
  50. SN2002ap (SN/GRB?) optical spectrographic observations
  51. GRB020127 Optical Observations
  52. Type Ib/c SN2002ap (SN/GRB?)
  53. Type Ib/c SN2002ap (SN/GRB?) Radio Observations
  54. GRB020124, optical observations
  55. GRB020127: Optical observations
  56. IPN triangulation of GRB020127 (=H1902)
  57. GRB020127 Optical Observations -- Erratum to GCN 1230
  58. GRB010921 Optical Observations
  59. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  60. GRB020124: Optical observations
  61. VLT observations of GRB 020124: The fading optical/near-infrared afterglow
  62. GRB020124: Optical observations
  63. GRB 020124: Optical observations
  64. GRB 020124 Optical Observations
  65. IPN triangulation of GRB020124 (HETE 1896)
  66. GRB 020124: Optical afterglow
  67. GRB020124(=H1896): Localization of a Long GRB by HETE
  68. HETE 1896: Optical observations
  69. GRB optical counterpart candidate in GCN 1217 is M dwarf
  70. Possible optical counterpart to a GRB
  71. GRB011212, Optical Observations
  72. Optical polarization observations for GRB011211
  73. Color indices of the afterglow of GRB011211
  74. GRB011212: Optical observations at Gunma
  75. GRB 011211, spectrum and optical photometry
  76. GRB 011130: Optical Observations of X-ray and Radio Sources
  77. GRB011212: Optical observations
  78. GRB 011212: optical observation at Asiago
  79. GRB 011211: Evidence for an Optical Break
  80. optical follow-up of GRB(XRF) 011211
  81. GRB 011212: optical observation at Oslo (relayed)
  82. GRB 011211: Optical Spectroscopy
  83. GRB 011211, Optical Observations
  84. GRB011212, BVRI field photometry
  85. GRB011211, BVRI field photometry
  86. GRB011212: Optical observations
  87. GRB011212 (=H10001): An X-Ray Rich GRB Detected by HETE
  88. Fading of the optical source associated of XRF 011211
  89. GRB 011211 Optical Observations: Likely Afterglow
  90. GRB 011130: Optical Observations of Chandra Sources
  91. GRB 011130: Optical Observations of Chandra sources
  92. GRB 011130: Magellan spectroscopy
  93. GRB011130, optical observations
  94. GRB 011130, K band observations
  95. GRB011130, optical observations
  96. GRB011130 (=XRF011130): Second Revised Localization by HETE
  97. GRB 011130 I-band Observation
  98. GRB011130 (XRF011130) optical observations
  99. XRF011130: Infrared Observations
  100. Detection of the X-ray afterglow of GRB011121 by BeppoSAX

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