Skip to main content
Testing. You are viewing the public testing version of GCN. For the production version, go to https://gcn.nasa.gov.
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"
  1. GRB050814: SWIFT/UVOT observation
  2. GRB050814: Refined analysis of the Swift-BAT burst
  3. GRB050813: Gemini Imaging
  4. GRB 050813: Gemini spectroscopy and redshifts of galaxies B and C
  5. GRB 050814: Swift XRT Afterglow Localization
  6. GRB 050814: Swift detection of a burst
  7. GRB 050813: Magellan detection of a high redshift galaxy cluster
  8. GRB050813: RTT150 optical observations
  9. GRB 050813: I-band observations
  10. GRB050813, SDSS pre-burst observations
  11. GRB 050813: KAIT optical limit
  12. GRB 050813: Swift-BAT refined analysis
  13. GRB 050813: Photometry of object in XRT error circle
  14. GRB050813: SWIFT/UVOT observation
  15. GRB 050813: Swift XRT afterglow localization
  16. RBO GRB 050714A and GRB 050716 observations
  17. GRB 050813: Possible Short Swift-BAT GRB
  18. GRB050813 (Swift 150139): P60 Observations
  19. Swift-BAT trigger 150131 is not a GRB
  20. GRB050807(=H3889): An X-Ray Rich GRB Localized by HETE
  21. Ongoing activity of SGR 1806-20: an intermediate burst 050811
  22. GRB050803: CrAO optical observations, no OT candidate
  23. Detection of an intermediate burst from SGR 1806-20 on August 8
  24. GRB 050730: WSRT Radio Observations
  25. GRB 050803: PROMPT BVRcIc Observations
  26. GRB 050807: ROTSE-III Optical Limits
  27. GRB 050730, optical observation
  28. GRB050805b: CrAO optical limit
  29. GRB050805a : Null detection report
  30. GRB050730, optical observations
  31. GRB050803, optical observations
  32. Swift-BAT trigger 149118 is very likely not a GRB
  33. Retraction of Swift Trigger 149131 (GRB 050805B)
  34. GRB 050805b: OHP optical limits
  35. GRB 050805b: TAROT optical limits
  36. GRB050805b: MASTER optical observations
  37. Possible GRB 050805B: Swift-BAT trigger 149131 may be a burst
  38. GRB050805a: MASTER optical candidat
  39. Swift-BAT trigger 149118 is probably not a GRB
  40. GRB050802: TNG optical observations
  41. GRB050803: Radio Observation
  42. GRB 050803: RTT150 optical observations
  43. GRB050801: Radio Observation
  44. GRB050730: Radio Detection
  45. GRB050803: CrAO optical observations, possible OT candidate
  46. GRB050803: Optical/UV Upper Limits from Swift-UVOT
  47. GRB 050803: Keck Observations
  48. GRB 050803: Swift-BAT refined analysis
  49. GRB 050802.422: Fading of the afterglow and detection of the host
  50. GRB050803: MASTER further analys
  51. GRB 050803, optical observations
  52. GRB 050803: Magellan Observations
  53. GRB 050803: early Swift XRT analysis results
  54. GRB 050803: TAROT optical limits
  55. GRB050803: MASTER optical observations
  56. GRB050802: Tentative absorption redshift
  57. GRB050803: Swift-BAT detection of a very long burst
  58. GCN GRB observation 050713A
  59. GRB050730: FORS1 and UVES/VLT low- and high-resolution spectroscopy
  60. GRB 050802: Swift/UVOT optical and UV detections
  61. GRB050802: CrAO optical observations
  62. GRB050801: Unchanged decay slope
  63. GRB050802 radio non-detection
  64. GRB 050730: OHP optical observations
  65. GRB 050802: early Swift XRT analysis results
  66. GRB 050802: Swift/UVOT observations
  67. GRB 050802 : Lulin Optical follow-up observation
  68. GRB 050802: Swift-BAT refined analysis
  69. GRB050801: Optical photometry and decay index
  70. GRB 050802: XRT position
  71. GRB 050802: Swift Gamma-ray Burst
  72. GRB050801: Swift/UVOT Optical and UV detections
  73. GRB 050730: Preliminary Analysis of MIKE Spectrum
  74. GCN 050801: early Swift XRT analysis results
  75. GRB 050801: Swift-BAT refined analysis
  76. GRB 050801, SMARTS optical/IR afterglow observations
  77. GRB 050801, afterglow observations
  78. GRB 050730, corrected photometry and break?
  79. GRB 050801: ROTSE-III Early Afterglow Break
  80. GRB050801: Swift-BAT detection of a burst
  81. GRB050801: GCN XRT position is incorrect
  82. GRB 050801: ROTSE-III Detection of Possible Counterpart
  83. GRB 050730: XRT refined analysis
  84. Correction to GCN Circ 3476 on GRB050525A
  85. GRB 050730: early TAROT optical observations
  86. GRB 050726: PROMPT Rc Observations
  87. GRB 050730: RTT150 optical observations
  88. Swift/UVOT photometry of GRB050730
  89. GRB 050730, spectra and optical photometry
  90. GRB050730: Refined BAT analysis of the Swift-BAT burst
  91. GRB 050730: Swift XRT afterglow observations
  92. GRB 050730 XMM-Newton observation
  93. GRB 050730: PROMPT VRcIc Observations
  94. GRB050730, afterglow observations
  95. GRB050730: confirmation of redshift
  96. GRB 050730: Redshift Measurement based on Magellan/MIKE Observations
  97. GRB 050730, SMARTS optical/IR afterglow observations
  98. GRB 050730 : Planned XMM-Newton observation
  99. GRB050730: Liverpool Telescope optical observations
  100. GRB 050730, optical candidate

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