Skip to main content
End of Swift Science Operations, CHIME Notices Unavailable During Upgrade. See news and announcements

GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

38655 results found.

  1. GRB 050904 BAT refined analysis of complete data set
  2. GRB 050904: Subaru Optical Spectroscopy
  3. GRB 050906: MARGE Optical Limits
  4. GRB 050906: Swift-BAT refined analysis
  5. GRB 050906: Swift XRT upper limit
  6. GRB 050906: Radio Observations
  7. GRB 050904: Keck I-band Imaging
  8. GRB050906: P60 Observations
  9. GRB 050904: more VLT NIR observations
  10. GRB 050904: Did SWIFT/XRT see the prompt GRB emission ?
  11. GRB 050906: Swift/BAT Detection of a possible burst
  12. GRB 050904: More SOAR
  13. GRB 050904: photometric redshift
  14. GRB 050904: Swift/UVOT observations
  15. GRB 050904: Afterglow Astrometry
  16. GRB 050904: NIR object inside the XRT error box
  17. GRB 050904: early Swift XRT analysis results
  18. GRB 050904: SOAR YJ and PROMPT Ic Observations
  19. GRB 050904: BAT refined analysis of partial data set
  20. GRB050904: Optical Observations
  21. GRB 050904: Environmental Constraints
  22. GRB 050904: Possible High-Redshift GRB
  23. GRB 050904: SOAR/PROMPT Observations
  24. GRB050904: P60 Observations
  25. GRB050904: Swift-BAT detection of a probable burst
  26. Swift-BAT triggers 153461-153465 are not GRBs
  27. Retraction of Swift-BAT trigger #153355
  28. GRB 050824: MDM Observations
  29. GRB 050827: Swift XRT preliminary analysis results
  30. IBAS Alerts 2641 and 2642: not a real GRB
  31. Swift Trigger #152652 is not a GRB
  32. GRB 050827 : OSN 1.5m optical observations
  33. GRB 050827: P200 NIR Observations
  34. GRB050827: Swift/UVOT upper limits
  35. GRB 050827: Optical Limit
  36. GRB 050827: XRT possible afterglow detection
  37. GRB 050826 : Lulin R band observation
  38. GRB050824: Maidanak optical limits
  39. GRB 050827: Swift-BAT refined analysis
  40. GRB050827: Swift-BAT detection of a burst
  41. Subaru Observations of GRB050724
  42. GRB 050826: Optical Candidate
  43. GRB050824, HETE-2 Observation
  44. GRB 050826: Swift XRT preliminary analysis results
  45. GRB 050826: BAT refined analysis
  46. GRB050826: Swift/UVOT early upper limits
  47. GRB 050826: Swift XRT position
  48. GRB050826: Swift-BAT detection of a long burst
  49. Possible GRB050825:MASTER optical observations
  50. Swift-BAT trigger 152038 is definitely not a GRB
  51. GRB050824: CORRECTION to UVOT observing times
  52. Swift-BAT trigger 152038 is probably not a GRB
  53. GRB050824: Swift/UVOT detection of fading afterglow
  54. GRB050824, I-band imaging
  55. GRB050824: Radio Observations
  56. GRB 050824: Spectroscopic redshift from the VLT
  57. GRB 050822: refined XRT analysis
  58. GRB 050824: XRT refined analysis and possible afterglow detection
  59. GRB 050824: BAT refined analysis of a soft weak burst
  60. GRB050824: MASTER:OT decay
  61. GRB050824: MASTER observation OT
  62. GRB050805a: MASTER optical candidat
  63. GRB 050824: ROTSE-III Optical Limits
  64. GRB050824: Swift-BAT detection of a burst
  65. GRB 050824 optical candidate
  66. GRB050820A: RTT150 optical observations
  67. GRB050820a: PROMPT RcIc Observations
  68. GRB050815: Maidanak optical observation
  69. XRF050509c: Radio upper limits from GMRT
  70. GRB050822: Swift/UVOT upper limits
  71. GRB 050820A BAT observations of second, larger episode of emission
  72. GRB050813: Maidanak I-band observations
  73. GRB 050822: Swift-BAT refined analysis
  74. GRB050525, GRB050607, GRB050802 BVRcIc field photometry
  75. GRB050820A: RTT150 optical observations
  76. GRB 050820a - corrections to GCN 3846
  77. Swift/UVOT UV Photometry of GRB 050820B
  78. GRB 050822: ROTSE-III Prompt Optical Limits
  79. GRB 050822: Swift detection of a long burst
  80. Correction to Eiso calculation in GCN 3835 on GRB 050820A
  81. GRB050820A: Radio Observation
  82. GRB050825a - very long GRB like GRB041219a? (Konus-Wind observation)
  83. GRB050820a BVRcIc field photometry
  84. GRB050820B XMM-Newton observation
  85. GRB 050820B: Swift XRT position
  86. GRB050820B: Planned XMM-Newton observation
  87. GRB050820B: Refined analysis of the Swift-BAT burst
  88. GRB050820B: BAT-Swift detection of a bright GRB
  89. Swift/UVOT photometry of GRB050820
  90. GRB050820: refined XRT analysis
  91. GRB 050820: Early RAPTOR detections
  92. GRB 050820 Swift-BAT refined analysis
  93. GRB 050820: P60 Temporal Decay Index
  94. GRB 050820: High Resolution Spectroscopy from Keck
  95. GRB050819: refined XRT analysis
  96. GRB 050820: Swift detection of a GRB
  97. GRB050820: Optical afterglow from P60
  98. GRB 050819 Swift-BAT refined analysis
  99. GRB050819: Swift XRT position
  100. GRB050819: Swift-BAT detection of a weak 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