Skip to main content
Passing of Scott Barthelmy, GCN Founder 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"
  1. GRB070714B: TNG NIR observations
  2. Erratum : Suzaku WAM observation of GRB 070704
  3. GRB 070714A: Swift/UVOT Upper limits
  4. GRB 070714B: Swift/UVOT Upper Limits
  5. GRB 070714B: Swift-BAT spectral lag for the SHB
  6. GRB 070714B: confirmation of optical afterglow
  7. GRB 070616: No Evidence for I Band Afterglow
  8. GRB 070714A: Swift XRT refined analysis
  9. GRB070714B: Swift-XRT refined analysis
  10. GRB 070707: Swift-XRT follow-up observations
  11. GRB 070714b ("Bastille"): Optical Pre-Imaging (Clarification)
  12. GRB 070714 ("Bastille"): Optical Pre-Imaging
  13. GRB 070714B, Swift-BAT refined analysis of the short hard burst
  14. GRB 070714A, Swift-BAT refined analysis
  15. GRB 070714 : Liverpool Telescope optical counterpart ?
  16. GRB 070714: Swift detection of a bright burst, possibly short
  17. Swift detection of a possible burst (Trigger 284850)
  18. SN 2007bg - off-axis GRB?
  19. GRB 070704: RTT150 optical observations
  20. GRB 070704: Suzaku/WAM observation of the prompt emission
  21. Konus-Wind observation of GRB 070707
  22. Updated Swift/UVOT calibration
  23. GRB 070707: optical afterglow
  24. GRB 070707: object inside XRT error circle
  25. Swift/UVOT Observations of GRB070707
  26. Swift XRT observation of GRB 070707
  27. GRB 070707: VLT observations
  28. INTEGRAL GRB 070707 is a short hard burst
  29. INTEGRAL GRB 070707 is a short hard burst
  30. GRB 070707: A long GRB detected by INTEGRAL
  31. GRB 070707: A long GRB detected by INTEGRAL
  32. GRB 070429B: NIR Observations
  33. GRB070704: FAVOR optical observations
  34. GRB 070704 : Liverpool Telescope Observations
  35. GRB 070611: VLT observations
  36. VLA detection of GRB 070612A in C Band
  37. Konus-Wind observation of GRB 070626
  38. GRB 070704: Swift-XRT refined analysis
  39. Swift/UVOT Observations of GRB070704
  40. GRB 070704, Swift-BAT refined analysis
  41. GRB 070704: Correction to GCN Circ 6594
  42. GRB 070704: Swift detection of a burst
  43. GRB 070626: Suzaku/WAM observation of the prompt emission
  44. GRB 070626: IPN localization and Konus spectrum of a bright long burst
  45. GRB 070628 Swift-UVOT Refined Analysis
  46. GRB 070628: NIR detection of afterglow
  47. GRB 070628, Swift-BAT refined analysis
  48. GRB 070628: TAROT La Silla observatory optical observations
  49. GRB 070628: Swift XRT refined analysis
  50. GRB 070628: Watcher Observations
  51. Swift UVOT Observations of GRB 070628
  52. GRB 070628: Swift detection of a possible burst
  53. GRB 070612A: Allen Telescope Array Observations
  54. IBAS Alert n. 4638: Not a GRB
  55. OT20050728 was not an optical GRB afterglow
  56. INTEGRAL burst GRB070615: X-ray continued observations
  57. GRB 070616 : WIDGET simultaneous optical observations
  58. GRB 070616: Suzaku/WAM observation of the prompt emission
  59. IBAS Alert n.4637: not a GRB
  60. GRB 070612A: Second Epoch WSRT Radio Observations
  61. GRB070621: RTT150 optical observations
  62. GRB 070621: VLT optical observations
  63. GRB 070621: Swift/UVOT Upper Limits
  64. Keck Laser Guide Star Adaptive Optics Imaging of GRB 070621
  65. GRB 070621: Swift-BAT refined analysis
  66. WHT observations of GRB070621
  67. GRB070621: Swift XRT refined analysis
  68. GRB 070621: Gemini South optical imaging
  69. GRB 070621: UVOT-enhanced XRT position
  70. Observations of GRB070612A at Calar Alto
  71. GRB 070621: NOT observations
  72. GRB070621: OPTIMA-Burst optical upper limit
  73. GRB 070621: TAROT Calern observatory optical observations
  74. GRB 070621: Watcher Observations
  75. GRB 070621: ROTSE-III Prompt Optical Limits
  76. GRB 070621: Swift detection of a burst
  77. GMRT upper limit of GRB 070610/SWIFT J195509.6+261406 in 610 MHz
  78. GRB 070612A: TNG optical observations
  79. Swift/UVOT detection of GRB070616 optical afterglow.
  80. GRB070612A: Gemini Spectroscopic Redshift
  81. GRB 070612A: NOT observations
  82. GRB070616: Optical Observation by MITSuME Akeno
  83. GRB 070612B: Optical Observation by MITSuME Akeno
  84. GRB070616: Optical Observation by MITSuME Okayama
  85. GRB 070616, Swift-BAT further refined analysis
  86. GRB 070616: Swift XRT refined circular
  87. GRB 070612A: Possible WSRT Radio Detection
  88. GRB 070616: BTA astrometry and finding chart
  89. GRB 070616: BTA optical observations
  90. Swift/UVOT observations of GRB070616
  91. GRB 070616: TLS observation
  92. Swift XRT observations of the INTEGRAL burst GRB070615: Possible
  93. GRB 070616, Swift-BAT partial refined analysis
  94. GRB 070616: Swift detection of a burst
  95. GRB 070612B: optical observations
  96. UVOT Observations of INTEGRAL burst GRB070615
  97. VLA upper limit on GRB 070610
  98. GRB 070615
  99. GRB 070615: A long GRB detected by INTEGRAL
  100. SWIFT J195509.6+261406 (GRB 070610): further 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