Skip to main content
New! Super-Kamiokande JSON Notices and Schema v4.5.0. 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"

26368 results found.

  1. GRB 051016: PROMPT Observations
  2. GRB051016: Swift detection of a burst
  3. Photometric calibration of Swift/UVOT and Re-analysis of Swift/UVOT GRB 050922C data
  4. GRB 051012: Swift-BAT detection of burst yesterday
  5. Swift-BAT Trigger 159578 is a possible burst
  6. GRB 051006: Swift/UVOT Upper Limits
  7. GRB051008: optical candidate
  8. GRB 051008 - a low redshift low-luminosity burst?
  9. GRB051011: bright nebulae near error box
  10. GRB051011: MASTER optical observation
  11. GRB051008: Final refined analysis of the Swift-BAT burst
  12. GRB051008: Radio Observation
  13. GRB 051008, optical observations
  14. GRB 051008: early Swift XRT analysis
  15. GRB 051008: Swift UVOT Candidate
  16. GRB 051006: P60 Observations
  17. Swift-BAT trigger 158700 is a probable Cosmic Ray Shower Event
  18. GRB 051006: optical observations at Sierra Nevada
  19. GRB051006: Refined analysis of the Swift-BAT burst
  20. GRB051006: Swift detection of a burst
  21. GRB 050906, summary of radio observations
  22. GRB051001: Swift UVOT Upper Limits
  23. GRB 050925: Second Epoch WSRT Radio Observations
  24. GRB 051001: I-band limit
  25. GRB 051001: AAT infra-red observations
  26. GRB 051001: Swift-BAT refined analysis
  27. GRB 051001: Swift Detection of a Burst
  28. GRB 050820A: NIR photometry at the TNG
  29. GRB050925: Swift/XRT limits
  30. GRB/SGR 050925: IR Observations
  31. GRB 050922C: break in the lightcurve
  32. GRB050925: Swift UVOT upper limits
  33. Refined analysis of the Swift-BAT soft short burst
  34. GRB050925: Faulkes Telescope North R-band limit
  35. GRB050925: Swift-BAT detection of a short burst
  36. GRB050922C: TNG spectroscopic observations
  37. GRB050922B: refined XRT analysis
  38. GRB050922B: Swift UVOT early upper limits.
  39. GRB050922C: Optical Observations
  40. GRB 050922C: Swift XRT refined analysis
  41. HETE Fregate observations of GRB 050922C
  42. GRB 050922C: Swift-BAT refined analysis
  43. GRB 050922B: Swift-BAT refined analysis
  44. GRB 050922C: optical obserations
  45. GRB 050922C: NOT optical observations
  46. GRB 050922C: Swift detection of a bright burst
  47. GRB 050922B: ROTSE-III Optical Limits
  48. GRB 050922B,optical observation
  49. GRB050922B: Swift-BAT detection of a weak long burst
  50. GRB050820B: analysis of the XMM-Newton observation
  51. GRB050916: Swift/UVOT Upper Limits
  52. GRB 050916: Swift-BAT refined analysis
  53. Swift-BAT trigger 155764 is not a GRB
  54. Swift-BAT trigger 155764 is probably not a GRB
  55. Swift trigger 155764: bad XRT centroid
  56. Swift-BAT trigger 155535 is definitely not a GRB
  57. GRB050916 : Swift-XRT refined analysis
  58. GRB 050915B: Swift-BAT refined analysis
  59. GRB 050915B: Swift/UVOT Upper Limits
  60. GRB 050915a: IR Transient
  61. GRB 050915b, SMARTS optical/IR observations
  62. GRB050915B: Swift-BAT detection of a long bright burst
  63. GRB050915: Swift/UVOT upper limits
  64. GRB 050915: IR Observations
  65. GRB 050915: Swift XRT refined analysis
  66. GRB 050915: Swift-BAT refined analysis
  67. GRB 050915: Swift detection of a GRB
  68. GRB050911: Upper limit on X-ray afterglow
  69. Swift-BAT trigger 155072 ground analysis
  70. Swift-BAT trigger 155072 is probably not a GRB
  71. GRB 050908: DEIMOS spectrum and further analysis
  72. GRB 050911, optical content of Swift/XRT error box
  73. GRB 050911: Swift-BAT refined analysis
  74. GRB 050911: z~0.16 cluster in the field
  75. GRB050911: Swift-BAT detection of a long burst
  76. GRB 050910a: TAROT early optical limits
  77. WIRO observations in I of GRB 050908
  78. GRB 050906: Possible X-ray Counterpart
  79. GRB050908: Swift/UVOT Early upper limits
  80. GRB050908 : Swift-XRT refined analysis
  81. GRB 050908: Swift-BAT refined analysis
  82. GRB 050908: Optical observations
  83. GRB 050908: Optical Observations
  84. GRB 050908: Swift detection of a burst
  85. GRB 050906: Optical observations at the Very Large Telescope
  86. GRB 050904 BAT refined analysis of complete data set
  87. GRB 050904: Subaru Optical Spectroscopy
  88. GRB 050906: MARGE Optical Limits
  89. GRB 050906: Swift-BAT refined analysis
  90. GRB 050906: Swift XRT upper limit
  91. GRB 050906: Radio Observations
  92. GRB 050904: Keck I-band Imaging
  93. GRB050906: P60 Observations
  94. GRB 050904: more VLT NIR observations
  95. GRB 050904: photometric redshift
  96. GRB 050904: Swift/UVOT observations
  97. GRB 050904: NIR object inside the XRT error box
  98. GRB 050904: early Swift XRT analysis results
  99. GRB 050904: SOAR YJ and PROMPT Ic Observations
  100. GRB050904: Optical Observations

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