Skip to main content
JSON Notices via Email, Kafka Cron Jobs, Submitter Profile, GCN is Hiring. 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"

32580 results found.

  1. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  2. Further VLA observations of SGR 1806-20
  3. SGR 1806-20 and extragalactic short-duration GRBs
  4. Fourth Epoch VLA observations of SGR 1806-20
  5. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  6. SGR 1806-20: Temporal and Spectral behavior of radio transient
  7. ATCA observations of SGR 1806-20
  8. SGR 1806-20, RHESSI observations of the 041227 giant flare
  9. Third epoch observations of SGR 1806-20 with VLA
  10. Second Epoch VLA observations of SGR 1806-20
  11. Second-epoch VLA observations of SGR 1806-20
  12. SGR1806: Detection of a Sudden Ionospheric Disturbance
  13. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  14. VLA observations of SGR 1806-20
  15. SGR1806 VLA Observations
  16. VLA observations of SGR 1806-20
  17. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  18. GRB 041217: Optical observations
  19. GRB041219, early time observations
  20. The giant outburst from SGR 1806-20
  21. IPN localization of giant flare from SGR1806-20
  22. GRB041228: ROTSE-III Optical Observations
  23. GRB041219; RXTE ASM Observations
  24. NIR Observations of GRB 041219
  25. GRB041226: ROTSE-III Optical Observations
  26. GRB041223: decay of the afterglow
  27. GRB041224: ROTSE-III Optical Observations
  28. GRB 041224: near-infrared observations with REM
  29. GRB 041223: XRT afterglow spectrum and light curve
  30. GRB 041223 Fluence measured by Swift-BAT
  31. GRB041223: optical and NIR observations with REM
  32. Swift-BAT Time History of GRB041219
  33. GRB 041219: TAROT optical observations
  34. GRB 041223: J-band observations of the afterglow
  35. GRB 041223: Detection of Optical Transient with LCO40
  36. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  37. GRB 041219c: PROMPT Observations
  38. GRB041223: ROTSE-III Optical Observations
  39. GRB 041218: optical observations
  40. Very high activity of SGR 1806-20
  41. GRB 041219: Second Epoch WSRT Radio Observations
  42. GRB 041219: WSRT Radio Afterglow Detection
  43. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  44. GRB 041218: Optical observations
  45. GRB 041219 : optical follow-up observations
  46. Deep RAPTOR observations during GRB 041219
  47. GRB 041218 Optical Observations
  48. GRB 041219 Optical Observations
  49. GRB041219: Optical Afterglow Detection
  50. GRB041219: Continued NIR Observations
  51. GRB 041219: Radio Afterglow Detection
  52. GRB 041218 : Radio Observations
  53. GRB 041218: R-band optical observations
  54. GRB041218: Liverpool Telescope optical observations
  55. GRB041218: optical observations
  56. GRB041219: Confirmed NIR Afterglow
  57. Swift-BAT detection of the bright long burst GRB041219
  58. GRB 041218: Optical Observation
  59. GRB 041219: Infrared Afterglow Candidate
  60. GRB041219, BVRcIc field calibration
  61. GRB 041219: Infrared Afterglow Candidate
  62. GRB041218, BVRcIc field calibration
  63. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  64. GRB 041217: PROMPT Observations
  65. GRB041218: optical observations
  66. GRB041217: optical limit 30 min after GRB
  67. GRB 041218; optical candidate
  68. GRB 041218: Optical observations
  69. GRB 041217: LCO40 Optical Observations and Possible Candidates
  70. GRB041217: Optical Observations
  71. GRB041217: NIR and optical observations with REM
  72. GRB041217: Infrared Observations
  73. GRB041217: The First GRB Located On-Board Swift
  74. GRB041211: Faulkes Telescope continued optical monitoring
  75. Optical Transient in Lynx not a GRB
  76. Optical transient (GRB?) in Lynx
  77. GRB041211: Continued P60 Observations
  78. GRB041211, Faulkes Telescope optical observation
  79. GRB041211, BVRcIc field calibration
  80. GRB 041211: Infrared Observations
  81. GRB 041211: Optical follow-up in East Asian region
  82. GRB 041211(=H3622): A Long GRB Localized by the HETE WXM and SXC
  83. GRB041015: Near-Infrared observations
  84. GRB 040924: Afterglow Color
  85. GRB 041006: GETS Optical Afterglow Observation
  86. Summary of the recent bursts from SGR 1806-20
  87. GRB 041006: Optical Observations
  88. GRB041006, late-time optical photometry
  89. GRB041006: RTT150 Optical Observations
  90. GRB041015 : Multi epoch optical observations
  91. GRB041006: RTT150 Optical Observations
  92. GRB 041016: Optical limits
  93. GRB 041015: Optical Observations at Rikubetsu
  94. GRB041006: Near Infrared observations
  95. GRB040924, BVRcIc field calibration
  96. GRB 041015: Optical limit at Osaka University
  97. GRB041015 : Optical follow-up at Kiso
  98. GRB 041006 R observations in Loiano
  99. GRB041006: VLT observations of the afterglow and host galaxy
  100. GRB041006: Optical observations and Potential host galaxy

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