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"

26518 results found.

  1. GRB050916: Swift/UVOT Upper Limits
  2. GRB 050916: Swift-BAT refined analysis
  3. Swift-BAT trigger 155764 is not a GRB
  4. Swift-BAT trigger 155764 is probably not a GRB
  5. Swift trigger 155764: bad XRT centroid
  6. Swift-BAT trigger 155535 is definitely not a GRB
  7. GRB050916 : Swift-XRT refined analysis
  8. GRB 050915B: Swift-BAT refined analysis
  9. GRB 050915B: Swift/UVOT Upper Limits
  10. GRB 050915a: IR Transient
  11. GRB 050915b, SMARTS optical/IR observations
  12. GRB050915B: Swift-BAT detection of a long bright burst
  13. GRB050915: Swift/UVOT upper limits
  14. GRB 050915: IR Observations
  15. GRB 050915: Swift XRT refined analysis
  16. GRB 050915: Swift-BAT refined analysis
  17. GRB 050915: Swift detection of a GRB
  18. GRB050911: Upper limit on X-ray afterglow
  19. Swift-BAT trigger 155072 ground analysis
  20. Swift-BAT trigger 155072 is probably not a GRB
  21. GRB 050908: DEIMOS spectrum and further analysis
  22. GRB 050911, optical content of Swift/XRT error box
  23. GRB 050911: Swift-BAT refined analysis
  24. GRB 050911: z~0.16 cluster in the field
  25. GRB050911: Swift-BAT detection of a long burst
  26. GRB 050910a: TAROT early optical limits
  27. WIRO observations in I of GRB 050908
  28. GRB 050906: Possible X-ray Counterpart
  29. GRB050908: Swift/UVOT Early upper limits
  30. GRB050908 : Swift-XRT refined analysis
  31. GRB 050908: Swift-BAT refined analysis
  32. GRB 050908: Optical observations
  33. GRB 050908: Optical Observations
  34. GRB 050908: Swift detection of a burst
  35. GRB 050906: Optical observations at the Very Large Telescope
  36. GRB 050904 BAT refined analysis of complete data set
  37. GRB 050904: Subaru Optical Spectroscopy
  38. GRB 050906: MARGE Optical Limits
  39. GRB 050906: Swift-BAT refined analysis
  40. GRB 050906: Swift XRT upper limit
  41. GRB 050906: Radio Observations
  42. GRB 050904: Keck I-band Imaging
  43. GRB050906: P60 Observations
  44. GRB 050904: more VLT NIR observations
  45. GRB 050904: photometric redshift
  46. GRB 050904: Swift/UVOT observations
  47. GRB 050904: NIR object inside the XRT error box
  48. GRB 050904: early Swift XRT analysis results
  49. GRB 050904: SOAR YJ and PROMPT Ic Observations
  50. GRB050904: Optical Observations
  51. GRB050904: P60 Observations
  52. GRB 050904: TAROT optical limits
  53. GRB 050827 : OSN 1.5m optical observations
  54. GRB 050827: P200 NIR Observations
  55. GRB050827: Swift/UVOT upper limits
  56. GRB 050827: Optical Limit
  57. GRB 050827: XRT possible afterglow detection
  58. GRB 050826 : Lulin R band observation
  59. GRB050824: Maidanak optical limits
  60. GRB 050827: Swift-BAT refined analysis
  61. Subaru Observations of GRB050724
  62. GRB 050826: Optical Candidate
  63. GRB 050826: Swift XRT preliminary analysis results
  64. GRB 050826: BAT refined analysis
  65. GRB050826: Swift/UVOT early upper limits
  66. GRB050826: Swift-BAT detection of a long burst
  67. GRB050824: MASTER final analysis of the OT observations
  68. Swift-BAT trigger 152038 is probably not a GRB
  69. GRB 050824: XRT refined analysis and possible afterglow detection
  70. GRB 050824: BAT refined analysis of a soft weak burst
  71. GRB050824: MASTER:OT decay
  72. GRB050824: MASTER observation OT
  73. GRB050805a: MASTER optical candidat
  74. XRF050509c: Radio upper limits from GMRT
  75. GRB050822: Swift/UVOT upper limits
  76. GRB 050820A BAT observations of second, larger episode of emission
  77. GRB050813: Maidanak I-band observations
  78. GRB 050822: Swift-BAT refined analysis
  79. GRB050525, GRB050607, GRB050802 BVRcIc field photometry
  80. GRB050820B at FRAM
  81. Swift/UVOT UV Photometry of GRB 050820B
  82. GRB 050822: Swift detection of a long burst
  83. GRB050820a BVRcIc field photometry
  84. GRB050820B XMM-Newton observation
  85. GRB 050820a: NIR Observations by WIRO
  86. GRB 050820B: Swift XRT position
  87. GRB050820B: Refined analysis of the Swift-BAT burst
  88. GRB050820: refined XRT analysis
  89. GRB 050820 Swift-BAT refined analysis
  90. GRB050819: refined XRT analysis
  91. GRB 050820: Swift detection of a GRB
  92. GRB 050819 Swift-BAT refined analysis
  93. GRB050819: Swift-BAT detection of a weak burst
  94. GRB 050817: Optical observations
  95. GRB050817: Negative Optical Observations
  96. GRB 050814: continued fading
  97. GRB050815: Optical afterglow detection by Swift UVOT
  98. GRB050815: XRT refined analysis
  99. GRB050815: Refined analysis of the Swift-BAT burst
  100. GRB 050815: ROTSE-III Optical Limits

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