Skip to main content
New! CHIME and DSA-110 FRB Notices, IceCube Notices and Schema v6.1.1. 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"
  1. GRB060602A: Swift/UVOT upper limits
  2. GRB 060607B: Swift detection of a burst
  3. GCN 060607: Swift-UVOT obswervations.
  4. GRB 060607: Swift-BAT Refined Analysis
  5. GRB 060607: optical limit by "Pi of the Sky"
  6. GRB 060607: Swift-XRT Team refined analysis
  7. GRB 060607: IR observations
  8. GRB 060502B: A Bright Early-type Galaxy as Putative Host of the Short Burst
  9. VLT/UVES observations of GRB 060607
  10. GRB 060607: PROMPT Observations
  11. GRB 060605: RTT150 optical observations
  12. GRB 060607: REM NIR afterglow
  13. GRB 060607: Swift detection of a burst with bright optical counterpart
  14. GRB 060522: PROMPT Optical Limits
  15. GRB 060605 BAT refined analysis
  16. GRB 060605: Xinglong TNT optical observations
  17. GRB060602B : REM infrared observations
  18. GRB060605: Swift/UVOT detections
  19. GRB 060605: Swift-XRT Team refined analysis
  20. SALT spectroscopy of GRB 060605
  21. GRB 060605: TNG optical observations
  22. GRB 060605: RTT150 optical observations
  23. GRB060605: Spectral Observations and Redshift
  24. GRB 060605: ROTSE-III Optical Counterpart
  25. GRB 060605: Swift detection of a burst with optical counterpart
  26. GRB 060605: ROTSE-III Detection of Optical Counterpart
  27. GRB060604: Swift/UVOT detections
  28. GRB 060604: redshift
  29. GRB 060512: Keck Redshift
  30. GRB 060604 optical photometry
  31. GRB 060604: Swift-XRT Team refined analysis
  32. GRB 060604: BAT refined analysis
  33. GRB 060604A: ROTSE-III Optical Limits
  34. GRB 060604: Swift detection of a burst with possible optical counterpart
  35. GRB 060602A: Swift-BAT Refined Analysis: Correction
  36. GRB 060602B: XMM-Newton Survey Source
  37. GRB 060602B: Swift-XRT Refined Analysis
  38. GRB 060602B: Swift-BAT Refined Analysis
  39. GRB 060602B: Swift/UVOT observations
  40. GRB 060602A: Swift-BAT Refined Analysis
  41. GRB 060602B: RTT150 optical observations
  42. GRB 060211A : WIDGET simultaneous optical observations
  43. GRB060602A: optical observations(/transient?)
  44. GRB 060526: Tautenburg Second Epoch Observations
  45. GRB060602A: Bootes-IR observations
  46. GRB 060602B: Swift detection of a burst
  47. GRB060602B: Watcher observations - no OT candidate
  48. GRB060602B: BOOTES-IR candidate afterglow
  49. GRB060602 - SDSS Pre-Burst Observations
  50. GRB 060602: Swift detection of a burst
  51. GRB 060502A: Optical afterglow observations
  52. GRB 060526: Break in X-ray light curve
  53. GRB 060526: RTT150 optical observations
  54. GRB060526, optical observations
  55. GRB 051227 : WIDGET simultaneous optical observations
  56. GRB 051028 : WIDGET pre-trigger limit
  57. GRB 060526: RTT150 optical observations
  58. GRB 060526: Multiple Optical Flares
  59. GRB060526: afterglow fitting and probable jet break
  60. GRB 060526: RTT150 optical observations
  61. GRB060526: Optical counterpart from MIRO
  62. GRB060502b: optical observations
  63. GRB 060526: RTT150 optical observations
  64. GRB 060526: Tautenburg OT observation and light curve fitting
  65. GRB060526: optical observations
  66. GRB 060526: SMARTS optical/IR afterglow observations
  67. GRB060526: possible break in the optical light curve
  68. GRB 060526: REM observations
  69. GRB 060526: RTT150 optical observations, afterglow flattening
  70. GRB 060526: Optical Flare
  71. GRB 060526: MDM-2.4m Observations
  72. GRB 060526: Refined analysis of the Swift-BAT burst
  73. GRB 060526: RTT150 optical observations
  74. GRB060526: Further Swift-UVOT Observations
  75. GRB060526, optical observations
  76. GRB 060526: Magellan Redshift
  77. GRB 060526 Lulin optical observation
  78. GRB 060526: Swift/XRT Team refined analysis
  79. GRB 060526: TNG optical observations
  80. GRB 060526: ROTSE-III Observations of Optical Counterpart
  81. GRB 060526: Watcher Observations
  82. GRB060526 - SDSS Pre-burst Observations
  83. GRB 060526: Continued emission for the Swift burst
  84. GRB 060526: Swift detection of a burst with x-ray and optical afterglow
  85. GRB060505: VLT observations of the optical afterglow
  86. GRB 060413 : WIDGET simultaneous optical observations
  87. GRB 060522: Swift/UVOT Observations: Correction
  88. GRB 060522: Swift/UVOT Observations of the Optical Afterglow
  89. XMM-Newton observation of GRB060510b
  90. GRB060512: Late-Time P200 Observations
  91. GRB060522: z = 5.11 Keck-LRIS Redshift
  92. GRB 060522: Swift/XRT Team refined analysis
  93. GRB 060522: Swift-BAT Refined Analysis
  94. GRB 060522: REM NIR observations
  95. GRB 060522: TNG optical observations
  96. GRB 060522: Swift detection of a burst with possible optical afterglow
  97. GRB 060512: reanalysis of optical spectra
  98. GRB 060515: NIR observation
  99. GRB 060210: Jet Break in the XRT light curve
  100. GRB 060516: Refined analysis of the Swift-BAT burst

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