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"

20387 results found.

  1. GRB 050915B: optical afterglow
  2. Swift/UVOT Upper Limits for GRB061110b
  3. Swift/UVOT Upper Limits for GRB061110a
  4. GRB 061110B: Swift XRT refined analysis
  5. GRB061110B: Optical observations at Crni Vrh
  6. GRB 061110B: TAROT Calern observatory optical observations
  7. GRB 061110B: Swift detection of a burst
  8. GRB 061110: Candidate confirmed
  9. GRB 061110: ROTSE-III Optical Limits
  10. GRB 061110: Swift detection of a burst
  11. GRB061110A - Optical Non-detection
  12. GRB 061109: TAROT Calern observatory optical observations
  13. GRB 061027: TAROT La Silla observatory optical observations
  14. GRB 061028: Swift/XRT Astrometry Correction
  15. GRB 061102: Swift/UVOT Magnitude Upper Limits
  16. GRB 061102, XRT refined analysis
  17. GRB061102B: Super-LOTIS observations
  18. GRB 061028: Optical R passband observations
  19. GRB 061102B: Swift detection of a possible burst
  20. GRB 061102: Swift detection of a burst
  21. GRB 061028: VLA Observation
  22. GRB 061004: Swift/XRT Astrometry Correction
  23. GRB 060801: Swift/XRT Astrometry Correction
  24. GRB 061028: Futher P200 Observations
  25. GRB 061028: P200 Observations
  26. GRB 061028: SARA upper limit
  27. GRB 061028: z band imaging
  28. GRB061028: XRT refined analysis
  29. GRB 061028: Swift/UVOT Observations
  30. GRB 061028: TAROT Calern observatory optical observations
  31. GRB 061028: Swift detection of a burst
  32. GRB 061027, Swift refined analysis of a possible burst
  33. GRB 061027: Swift detection of a possible burst
  34. GRB061025: Swift XRT refined analysis
  35. GRB061025: Swift/UVOT observations
  36. GRB 061025: REM observations
  37. GRB 061025: ROTSE-III Optical Limits
  38. Swift XRT boresight update
  39. GRB 061021: Swift/UVOT Observation
  40. GRB 061021: Swift detection of a burst
  41. GRB 061019: Super-LOTIS upper limit
  42. GRB060904b: optical observations
  43. GRB 061019: SARA upper limit
  44. GRB 061019: Swift/UVOT upper limit
  45. GRB061019: Swift XRT refined analysis
  46. GRB 061019, Swift-BAT refined analysis
  47. GRB 061019: TAROT La Silla observatory optical observations
  48. GRB 061019: REM K-band candidate afterglow
  49. GRB 061007: RHESSI Spectral Fit
  50. GRB 061007: Suzaku/WAM observation of the prompt emission
  51. GRB 061006: astrometry-corrected XRT position
  52. Konus-Wind observation of GRB 061007
  53. GRB061007: Swift UVOT followup observations
  54. GRB 061006: optical afterglow
  55. GRB 061007: OA fading and VLT redshift
  56. GRB 061007: Swift XRT refined analysis
  57. GRB 061006: Swift/UVOT optical observations
  58. GRB 061007: Swift detection of a burst with an optical counterpart
  59. GRB 061006: VLT observation
  60. GRB 061006: Swift-XRT Team Refined Analysis
  61. GRB 060930: near-IR afterglow candidate retraction
  62. GRB 061004: Optical afterglow candidate and redshift
  63. GRB 061004: Swift detection of a burst
  64. Konus-Wind observation of GRB 060928
  65. IGR J08408-4503 (= V* LM Vel): Swift detection of a transient
  66. GRB 060928: Swift observations
  67. GRB 060928: RHESSI Spectral Fit
  68. IPN triangulation of GRB060928 (long, exceptionally bright)
  69. GRB 060930: near-IR afterglow candidate
  70. GRB 061002: Swift-XRT Team Refined Analysis
  71. VLA observations of GRB 060926
  72. GRB061002 - SDSS Pre-Burst Observations
  73. GRB 060908: Detection of a possible host
  74. GRB 060807: Detection of a possible host galaxy
  75. GRB 060923A: VLA K-band Observations
  76. GRB 060930: Xinglong TNT optical observations
  77. GRB 060929: Swift/UVOT Optical Observations
  78. GRB 060929: TNG K-band observations
  79. GRB060929: Optical limit
  80. Liverpool Telescope observations of GRB 060929
  81. GRB060908: optical observations
  82. GRB 060927: Swift/UVOT Optical Observations
  83. GRB 060927: Swift XRT Team refined analysis
  84. GRB 060927 optical limit
  85. GRB 060927: Xinglong TNT optical observations
  86. GRB 060927, optical observation
  87. GRB 060926: MASTER: first minutes decay
  88. GRB060927 - SDSS Pre-Burst Observations
  89. GRB 060926: Swift-UVOT Detections
  90. GRB 060926: OPTIMA-Burst -- further observations
  91. GRB 060923A: Radio Observations
  92. GRB 060926: RTT150, UVOT afterglow candidate confirmation
  93. GRB 060923C: VLA Observation
  94. GRB 060923C: NIR afterglow confirmed
  95. GRB060923C: AROMA optical obsevation
  96. GRB 060923C, optical observation
  97. GRB 060923C: VLT J-band observations
  98. GRB 060923A: Keck and Gemini Observations
  99. GRB 060923C: Xinglong TNT optical observations
  100. GRB 060923C: Swift detection of a burst

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