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"

25905 results found.

  1. GRB 051221B: Swift-XRT Team Refined Analysis
  2. GRB 060219: Partial refined analysis of the Swift-BAT burst
  3. GRB060218: Radio Afterglow Discovery
  4. GRB 060219: Swift-XRT position typo correction
  5. GRB 060218: MDM Redshift
  6. GRB 060219: Swift-XRT position
  7. GRB 060218: optical/nIR observations at La Palma
  8. GRB 060219: Swift-BAT detection of a weak burst
  9. Oddball GRB 060218, transient or GRB?
  10. GRB060218: Swift/XRT Team preliminary analysis of the possible burst
  11. Brightening of the Optical Counterpart of the Possible GRB 060218
  12. GRB 060218: MDM Observations
  13. GRB 060218: Pre-burst detection of a possible host galaxy
  14. GRB 060218A: ROTSE-III Possible Optical Flare
  15. GRB060218: Swift/XRT refined position of a possible burst
  16. Preliminary refined analysis of the Swift-BAT trigger 191157
  17. Further UVOT Observations of the Candidate Optical Afterglow for GRB 060218
  18. GRB 060211B: Swift/UVOT Upper Limits
  19. GRB 060218: Swift XRT Position
  20. GRB 060218: Swift-BAT detection of a possible burst
  21. GRB 060213: optical afterglow not confirmed
  22. Swift UVOT observations of GRB060213
  23. GRB 060213: optical afterglow candidate
  24. GRB060213: Swift XRT observations and possible afterglow candidate
  25. GRB 060206: Confirmation of Rapid Fading at Optical Wavelengths
  26. GRB 060211b: WIRO NIR Observations
  27. GRB060206: Swift XRT observations of an unbroken powerlaw decay
  28. GRB 060213: IPN localization
  29. GRB 060210: Radio Observations
  30. GRB 060211a: WIRO NIR Observations
  31. GRB060211B: REM optical and NIR observations
  32. GRB 060211B: BAT detects no additional burst emission beyond T + 122 sec
  33. GRB 060211A: Further refined analysis of the Swift burst
  34. GRB060121: optical observations
  35. GRB060105: optical observations
  36. GRB 060210: ARC NIR Detection of Afterglow and Possible Host Galaxy
  37. GRB 060211b: P60 Observations
  38. GRB 060211A: Partial refined analysis on the Swift-BAT burst
  39. GRB 060206: SOAR Detections
  40. GRB 050826: Optical Afterglow and Host Galaxy
  41. GRB 060210: Further refined analysis of the Swift-BAT burst
  42. GRB 060211B: Swift/BAT refined analysis
  43. GRB060210: Swift/UVOT Upper Limits
  44. GRB 060211B: Swift-XRT Team refined analysis
  45. GRB060211b: optical observation
  46. GRB060211B: Swift/XRT position
  47. GRB 060210: Optical Observations
  48. GRB 060211A: Swift XRT Team Refined Analysis
  49. GRB 060211B: Swift-BAT detection of a burst
  50. GRB060211: Faulkes North observation
  51. GRB 060211: Swift detection of a long burst
  52. GRB 060210: Refined analysis of the Swift-BAT burst
  53. GRB060210: Swift XRT Refined Analysis
  54. GRB 060210 : Xinglong and Lulin optical limit
  55. GRB060210: Optical Observations
  56. GRB060210: Gemini absorption spectroscopy
  57. GRB060210: Early Optical Observations
  58. GRB 060210: optical evolution
  59. GRB060210:Faulkes Telescope North Afterglow Confirmation
  60. GRB 060210: candidate afterglow
  61. GRB 060210: Swift detection of a burst
  62. GRB060210: Optical afterglow
  63. GRB 060206: Swift/UVOT Observations
  64. Swift-BAT trigger 180931 is not a GRB
  65. GRB060209: RTT150 optical observations
  66. GRB 060209 : TAROT optical observation
  67. GRB 060209(?): Swift-BAT detection of a possible burst
  68. GRB 060206: near-infrared observations (JK' imaging)
  69. GRB 060206: WSRT Radio Observations
  70. GRB 060203: Swift/UVOT upper limits
  71. GRB 060206: TTT Observations
  72. GRB 060206: More PROMPT Detections
  73. GRB 060121 : WIDGET Pre-trigger limit
  74. GRB 060206: Tenagra II Observations
  75. GRB 060206: PROMPT Detections
  76. Retraction of orphan GRB afterglow candidate
  77. GRB060204a: Swift XRT Source is not GRB Afterglow
  78. GRB 060206: optical observations at Asiago
  79. Orphan GRB Afterglow candidate
  80. GRB 060204b: pseudo-z from spectral parameters of the prompt emission
  81. GRB 060206: Subaru/FOCAS optical spectroscopy
  82. GRB 060206: IR Detection of the Afterglow
  83. GRB 060206: Lick 3m Spectroscopy
  84. GRB 060204A: ROSAT Pointing
  85. GRB 060206: Super-LOTIS observations
  86. GRB060204A: Swift/UVOT observations
  87. GRB 060206: Swift-BAT refined analysis
  88. GRB 060206 : Lulin optical observations
  89. GRB060206: Swift XRT Refined Analysis
  90. GRB060206: Liverpool Telescope observation
  91. GRB 060206: Spectroscopic Redshift
  92. GRB060206: P60 Optical Observations
  93. GRB 060206: KAIT observations
  94. GRB060206: Swift XRT Position
  95. GRB060206: SARA Detection
  96. GRB 060206: RAPTOR observations of afterglow candidate variability.
  97. GRB 060206: High redshift burst
  98. GRB060204a: Swift XRT Detection of an Afterglow Candidate
  99. GRB060206 - Swift UVOT Confirmation of Optical Afterglow
  100. GRB060206: Optical afterglow

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