Skip to main content
Updates to LVK & CHIME Notices, Schema v7.2.3! 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"

28077 results found.

  1. GRB 070808: Xinglong TNT optical Upper Limit
  2. GRB 070808: ROTSE-III Optical Limits
  3. GRB 070808: Swift detection of a burst
  4. GRB061121A: PROMPT Observations
  5. GRB070805 XRT and UVOT afterglow candidate
  6. GRB070612A: Radio upper limit from GMRT
  7. GRB 070721B: correct afterglow position
  8. GRB 070805: Swift XRT initial analysis.
  9. GRB 070805: Swift/UVOT initial analysis
  10. GRB 070805: Swift detection of a burst
  11. Swift detection of a outburst from SAX J1810.8-2609
  12. VLA non-detection of GRB 070721B
  13. GRB 070802: REM optical observations
  14. GRB 070724B: Swift-XRT afterglow confirmation
  15. GRB 070802: Swift-XRT refined analysis
  16. GRB070802: Swift/UVOT upper limits
  17. GRB 070802: Confirmation of the optical afterglow
  18. GRB 070802: VLT redshift
  19. GRB 070802: refined Swift XRT position
  20. GRB 070802: V-band detection of the candidate afterglow
  21. GRB 070802: LCO I-band candidate
  22. GRB 070802: GROND J band candidate
  23. GRB 070802: LCO optical observations
  24. GRB 070802: Swift detection of a burst
  25. Swift/UVOT detection of GRB070714B
  26. AGILE-ACS position for the SGR 1806-20 July 27 burst
  27. GRB 070729: LCO optical imaging
  28. VLA upper limit on short hard burst GRB 070714B
  29. GRB070729: Swift/UVOT upper limits
  30. GRB 070729: Swift-XRT refined analysis
  31. GRB 070729: Magellan NIR Observations
  32. GRB 070724B: P60 Observations
  33. GRB 070729: Swift detection of a short hard burst
  34. GRB 070724B: Swift/UVOT Upper limits
  35. GRB070721A: Swift/UVOT Detection of a Weak Afterglow
  36. GRB 070724B: Swift-XRT afterglow likely candidate
  37. GRB 070721A: optical observations
  38. GRB 070724B: Swift-XRT afterglow candidates
  39. Four radio sources in Swift-XRT error box of GRB 070724
  40. GRB 070724: optical observations
  41. GRB 070724: P60 and Gemini Observations
  42. GRB 060814 - Keck host detection and redshift
  43. GRB 070724: IR observations
  44. GRB 070724: Closer association with DSS source
  45. Swift/UVOT refined analysis of GRB070724
  46. GRB 070724: Swift-XRT Team refined analysis
  47. GRB 070724: Pre-Imaging Shows a Source in the XRT Error Circle
  48. Short-Hard GRB070714B: PROMPT Observations
  49. GRB 070721B: further observations and analysis
  50. GRB 070724: Swift detection of a burst
  51. GRB 070326: Detection of first burst from BAT Slew Survey (BATSS)
  52. GRB 070714B: Keck observations
  53. GRB 070721B: optical observations and proposed redshift
  54. Swift/UVOT observations of GRB070721B optical afterglow.
  55. Swift/UVOT Observations of GRB070721A
  56. GRB 070721B : Faulkes Telescope South observations
  57. GRB 070721B: Swift-XRT refined analysis
  58. GRB 070721A : Faulkes Telescope South optical limit
  59. GRB 070721A: Swift/XRT refined analysis
  60. GRB070721B: A bright UVOT candidate
  61. GRB 070721B: Swift detection of a burst
  62. GRB 070721: Swift detection of a possible burst
  63. GRB070714B: TNG NIR observations
  64. GRB 070714A: Swift/UVOT Upper limits
  65. GRB 070714B: Swift/UVOT Upper Limits
  66. GRB 070714B: confirmation of optical afterglow
  67. GRB 070616: No Evidence for I Band Afterglow
  68. GRB 070714A: Swift XRT refined analysis
  69. GRB070714B: Swift-XRT refined analysis
  70. GRB 070707: Swift-XRT follow-up observations
  71. GRB 070714b ("Bastille"): Optical Pre-Imaging (Clarification)
  72. GRB 070714 ("Bastille"): Optical Pre-Imaging
  73. GRB 070714 : Liverpool Telescope optical counterpart ?
  74. GRB 070714: Swift detection of a bright burst, possibly short
  75. Swift detection of a possible burst (Trigger 284850)
  76. GRB 070704: RTT150 optical observations
  77. GRB 070707: optical afterglow
  78. GRB 070707: object inside XRT error circle
  79. Swift/UVOT Observations of GRB070707
  80. Swift XRT observation of GRB 070707
  81. GRB 070707: VLT observations
  82. GRB 070429B: NIR Observations
  83. GRB070704: FAVOR optical observations
  84. GRB 070704 : Liverpool Telescope Observations
  85. GRB 070611: VLT observations
  86. VLA detection of GRB 070612A in C Band
  87. GRB 070704: Swift-XRT refined analysis
  88. Swift/UVOT Observations of GRB070704
  89. GRB 070704: Correction to GCN Circ 6594
  90. GRB 070704: Swift detection of a burst
  91. GRB 070628 Swift-UVOT Refined Analysis
  92. GRB 070628: NIR detection of afterglow
  93. GRB 070628: Swift XRT refined analysis
  94. Swift UVOT Observations of GRB 070628
  95. GRB 070628: Swift detection of a possible burst
  96. GRB 070612A: Allen Telescope Array Observations
  97. OT20050728 was not an optical GRB afterglow
  98. INTEGRAL burst GRB070615: X-ray continued observations
  99. GRB 070616 : WIDGET simultaneous optical observations
  100. GRB 070612A: Second Epoch WSRT Radio Observations

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