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"

31728 results found.

  1. GRB 060801: Swift/XRT Astrometry Correction
  2. GRB 061028: Futher P200 Observations
  3. GRB 061028: MDM Observations
  4. GRB 061028: P200 Observations
  5. GRB 061028: SARA upper limit
  6. GRB 061028: z band imaging
  7. GRB061028: XRT refined analysis
  8. GRB 061028: Swift/UVOT Observations
  9. GRB 061028, Swift-BAT refined analysis
  10. GRB 061027, Swift refined analysis of a possible burst
  11. GRB061025: ROTSE-III Confirmation of Optical Counterpart
  12. GRB061025: Swift XRT refined analysis
  13. GRB061025: Swift/UVOT observations
  14. GRB 061019: MITSuME upper limits
  15. GRB 061025: REM observations
  16. GRB 061025: Gemini-S observations
  17. GRB061025: Swift XRT position
  18. GRB 061025: ROTSE-III Optical Limits
  19. Swift XRT boresight update
  20. GRB 061021, Swift-BAT Lag analysis
  21. Konus-Wind observation of GRB 061021
  22. GRB 061021 - VLT spectrum without lines
  23. GRB 061021: Swift-XRT refined analysis
  24. GRB 061021: Swift/UVOT Observation
  25. GRB 061021, Swift-BAT refined analysis
  26. GRB 061019: Super-LOTIS upper limit
  27. GRB060904b: optical observations
  28. GRB061019: optical observations
  29. GRB061019: optical observations
  30. GRB 061019: SARA upper limit
  31. GRB 060930: MARGE Optical Limits
  32. GRB 061019: Swift/UVOT upper limit
  33. GRB 061019: SMARTS afterglow confirmation
  34. GRB061019: Swift XRT refined analysis
  35. GRB 061019, Swift-BAT refined analysis
  36. GRB 061019: REM K-band candidate afterglow
  37. GRB061019: Swift/XRT position
  38. GRB 060825: GORT Observations
  39. GRB 061007: Second Epoch ATCA Radio Observations
  40. GRB 061007: RHESSI Spectral Fit
  41. GRB 061007: Suzaku/WAM observation of the prompt emission
  42. GRB 061006: astrometry-corrected XRT position
  43. Konus-Wind observation of GRB 061007
  44. GRB 060928: Confirmation of the X-ray afterglow detected by Swift
  45. GRB 061007: ATCA Radio Observations
  46. GRB061007: Swift UVOT followup observations
  47. GRB 061006: optical afterglow
  48. GRB 061007: OA fading and VLT redshift
  49. GRB 061007: Magellan Spectroscopy
  50. GRB 061007: Correction to GCN 5712
  51. GRB 061007: Swift-BAT refined analysis
  52. GRB 061007: Swift XRT refined analysis
  53. GRB 061006: Swift/UVOT optical observations
  54. Konus-Wind observation of the short hard GRB 061006
  55. GRB 061007 - FTS early brightening and power law decay
  56. GRB 061007 - Faulkes Telescope South Afterglow Confirmation
  57. GRB 061007: ROTSE-III Detection of Optical Counterpart
  58. GRB 061006: VLT observation
  59. GRB 061006: Swift-BAT refined analysis of the short-hard burst
  60. GRB 061006: Swift-XRT Team Refined Analysis
  61. GRB061006 (Swift 232585) might be a short-hard GRB
  62. GRB061006: Faulkes Telescope South Observations
  63. GRB 061004: Optical afterglow candidate and redshift
  64. GRB 061004: Las Campanas Optical/NIR Observations
  65. GRB061004: Swift/UVOT optical observations
  66. GRB 061004: Swift-XRT Team Refined Analysis
  67. GRB 061004, Swift BAT refined analysis
  68. GRB 061004: Nearby 2MASS Galaxy
  69. GRB 060928: Correction to GCN 5690
  70. Konus-Wind observation of GRB 060928
  71. GRB 060928: Suzaku/WAM observation of the prompt emission
  72. GRB 060928: Swift observations
  73. GRB 060928: RHESSI Spectral Fit
  74. IPN triangulation of GRB060928 (long, exceptionally bright)
  75. GRB061002: Swift UVOT followup observations
  76. GRB 060930: near-IR afterglow candidate
  77. GRB 061002: Swift-XRT Team Refined Analysis
  78. VLA observations of GRB 060926
  79. GRB 061002, Swift-BAT refined analysis
  80. GRB 060908: Detection of a possible host
  81. GRB 060923A: Probable host galaxy in the R-band
  82. GRB 060807: Detection of a possible host galaxy
  83. GRB 060923A: VLA K-band Observations
  84. GRB060930: Faulkes Telescope South observation
  85. GRB 060929: Further XRT Refined Analysis
  86. GRB 060929: Swift/UVOT Optical Observations
  87. GRB 060930: ROTSE-III Optical Limits
  88. GRB 060927 : GAO 150cm telescope optical observation
  89. GRB060929: Swift-XRT refined analysis.
  90. GRB 060929, Swift-BAT further refined analysis - late-time flare
  91. GRB 060929: TNG K-band observations
  92. GRB 060929, Swift-BAT refined analysis
  93. GRB060929: Optical limit
  94. GRB 060929: BART observation
  95. GRB 060929: BOOTES-IR & OSN observations
  96. GRB060908: optical observations
  97. GRB 060729: An update on the late-time Swift observations
  98. GRB060923C: optical limit
  99. GRB060927: optical observations
  100. test of new software, grb

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