Skip to main content
Updates to LVK & CHIME Notices, Schema v7.2.3! 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"

42185 results found.

  1. GRB 060108: VLT K-band observations
  2. GRB 060111: TAROT optical observation
  3. GRB 060111: possible UVOT counterpart
  4. GRB060111 : XRT refined analysis
  5. GRB 060111: ROTSE-III Optical Limits
  6. GRB 060111: Swift detection of a burst
  7. GRB 060110: Mitsume optical observations
  8. GRB 060108: z-band imaging from Gemini-North
  9. GRB 060110a: RAPTOR detection of early optical emission.
  10. GRB 060110: UKIRT K-band observations
  11. GRB 060110: ROTSE-III Confirmation of Optical Counterpart
  12. GRB060110, optical observation
  13. GRB 060110: Super-LOTIS observations
  14. GRB 060110: Optical observation
  15. GRB 060110: Correction
  16. GRB 060110: Optical limit
  17. GRB 060110: Swift-BAT detection of a burst
  18. GRB 060109: Refined Swift-XRT analysis
  19. GRB 060109: Swift/UVOT upper limits
  20. GRB060109, optical observation
  21. GRB 060108: ISAS early observations and near IR upper limit
  22. GRB060108: P200 Ks Observations
  23. GRB 060108: early UKIRT K-band observations
  24. GRB 060109: Swift Detection of a long burst
  25. GRB 060108: a dark burst?
  26. GRB 060108: Refined XRT analysis
  27. GRB 060108: VLT J-band observations
  28. GRB 060108: Mitsume optical observations
  29. GRB 060108: Swift/UVOT upper limits
  30. GRB060108: SDSS pre-burst observations
  31. GRB060108: Faulkes Telescope observation
  32. GRB060108, optical observation
  33. GRB 060108: Refined analysis of the Swift-BAT burst
  34. GRB 060108: Swift XRT position
  35. GRB060108: Swift detection of its 100th GRB
  36. GRB 060105: Radio observations
  37. GRB 060105: MDM Observation
  38. Konus-Wind observation of GRB 060105
  39. GRB 060105: ISAS observations and near IR upper limit
  40. GRB 060105: Mitsume optical observations
  41. GRB 060105: BAT refined analysis
  42. GRB 060102 - no XRT afterglow
  43. GRB 060105: XRT refined analysis
  44. GRB060105: Suzaku-XIS and -HXD observation plan
  45. GRB060105, optical observation
  46. GRB060105 : Kiso optical observation
  47. GRB060105: Swift detection of a bright long burst
  48. Swift-BAT trigger 175653 is not an astrophysical source
  49. GRB 060102: MDM Observation
  50. Swift-BAT trigger 175653 is probably not a GRB
  51. GRB 060102: Swift-BAT refined analysis
  52. GRB 060102: Swift-BAT detection of a burst
  53. GRB051211B: optical observations
  54. GRB051227: SARA Observations
  55. GRB 051221B: Optical Observations with Kuiper 1.54m
  56. GRB 051227: Likely host galaxy underlying afterglow position
  57. GRB 051227: optical observation
  58. GRB 051221A: VLA Radio Observations
  59. GRB051227: Radio Observations
  60. GRB 051227: Confirmed fading from Gemini observations
  61. GRB051227: further analysis of VLT images
  62. GRB 051227: optical afterglow
  63. GRB 051227: Swift/UVOT Upper Limits (Possible U-band
  64. GRB 051227: Gemini observations
  65. GRB 051227: Keck Spectroscopy
  66. GRB 051227: Magellan r'-band Imaging/Astrometry
  67. GRB 051227: refined analysis of VLT images
  68. GRB 051227: P60 Observations
  69. GRB 051227: MDM Observation
  70. GRB 051227: R-band object in the XRT error circle
  71. GRB 051227: Joint Swift-HETE Spectral Analysis
  72. GRB 051227: XRT refined analysis
  73. GRB 051227: Further analysis of the Swift-BAT burst
  74. GRB 051227: Refined analysis of the Swift-BAT burst
  75. GRB051227: SDSS pre-burst observations
  76. GRB 051227, optical observation
  77. GRB 051227: Swift detection of a burst
  78. GRB051117B: optical observation
  79. Konus-Wind observation of GRB 051221A
  80. GRB051221A: Suzaku WAM observation of the prompt emission
  81. GRB 051221A: MDM Optical Observations
  82. GRB051016: analysis of the XMM-Newton observation
  83. GRB 051221A: Detection at 251nm with Swift UVOT
  84. GRB 051221A: Chandra Afterglow Position
  85. GRB 051221A: Refined spectral and temporal analysis of the Swift-BAT short hard burst
  86. GRB 051221B: ROTSE-III Optical Limits
  87. GRB 051221B: TAROT optical limits
  88. GRB 051221A: WSRT Radio Observations
  89. GRB 051221: Redshift from Gemini
  90. GRB 051221: Continued fading of optical afterglow
  91. GRB 051221B: Refined analysis of the Swift-BAT burst
  92. Possible GRB 051221B: MDM Optical Detection
  93. GRB 051221A: RAPTOR Fading Counterpart Constraint
  94. GRB 051221B: BOOTES optical observations.
  95. Possible GRB 051221B: Swift XRT position
  96. GRB 051211A: Evidence This Is a Short Burst from Analysis of Spectral
  97. Swift-BAT detection of a possible burst
  98. GRB 051221: Discovery of fading optical afterglow
  99. GRB 051221: Swift XRT refined analysis
  100. GRB 051221: Possible nearby cluster

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