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"

45517 results found.

  1. GRB 070612: Swift detection of a burst
  2. GRB 070610: OPTIMA-Burst detection of continued strong flaring activity
  3. GRB 070610: SARA upper limit
  4. GRB 070610: Swift-XRT refined analysis
  5. GRB 070610: TLS RRM sees flaring behaviour - Galactic transient?
  6. GRB 070611: Swift/UVOT Observations
  7. GRB 070611: Swift-XRT refined analysis
  8. GRB 070611, Swift-BAT refined analysis
  9. GRB 070610: Optical observations from OSN
  10. GRB 070610: Watcher Observations
  11. GRB 070611: VLT redshift
  12. GRB 060121 : pseudo-z = 1.9 ('intermediate-duration' burst)
  13. GRB 070611: ROTSE-III Detection of Late Rising Optical Counterpart
  14. GRB 070611; Swift-XRT position
  15. GRB 070611: ROTSE-III Optical Limits
  16. GRB 070611: Swift detection of a burst
  17. GRB 070610: Swift-UVOT Upper Limits
  18. GRB 070610: OPTIMA-Burst high-time-resolution optical observations
  19. GRB 070610, Swift-BAT refined analysis
  20. GRB 070610; Swift-XRT position
  21. GRB 070610: Swift detection of a burst
  22. GRB 070412: TAROT Calern observatory optical observations
  23. GRB 070411: TAROT Calern observatory optical observations
  24. GRB 070419A, deep LBT photometry and possible supernova detection
  25. GRB070520B: optical observations
  26. GRB070520: optical observation
  27. GRB070518: optical observation
  28. GRB070521: optical observation
  29. Swift/UVOT refined analysis of GRB070531
  30. GRB 070531: NOT nIR observations
  31. GRB 070531: Swift-BAT refined analysis
  32. GRB 070531: I-band observations from IAC80
  33. GRB 070531: Swift-XRT position
  34. GRB 070531: Liverpool Telescope Optical Observations
  35. GRB 070531: Swift detection of a burst
  36. GRB 070529: SARA upper limit
  37. Swift/UVOT refined analysis of GRB070529
  38. GRB 070529: MARGE Observations
  39. GRB 070529: Optical aterglow from MIRO
  40. GRB 070529: Gemini Redshift
  41. GRB 070529: Swift-XRT refined analysis
  42. GRB 070529, Swift-BAT refined analysis
  43. GRB 070529: Xinglong TNT Optical Upper Limit
  44. GRB 070529: Swift detection of a burst with an optical aterglow
  45. GRB 070412: Deep Keck imaging
  46. Swift Triggers 280447, 280450 and 280451 are invalid
  47. Swift trigger 280447 is probably a Galactic transient
  48. GRB 070518, deep LBT photometry
  49. GRB 070518: MARGE Observations
  50. GRB 070521: pseudo-z ~ 2.28 from prompt emission spectrum
  51. Konus-Wind observation of GRB 070521
  52. GRB 070518: optical observation
  53. GRB070521: Second Epoch Gemini Imaging
  54. GRB070521: NIR observations
  55. GRB070520B: NIR observations
  56. GRB 070521: Swift/UVOT Upper Limits
  57. GRB 070521, optical observation
  58. GRB 070521: Swift-XRT refined analysis
  59. GRB 070521: Keck imaging
  60. GRB070521: Gemini Observations
  61. GROND upper limits of GRB 070521
  62. GRB 070521 Milagro GeV/TeV Observations
  63. GRB 070520B: SARA upper limit
  64. GRB 070520A: SARA upper limit
  65. GRB 070521: SARA upper limit
  66. GRB 070521: Subaru observations and possible host detection
  67. GRB070518: Optical/NIR observation
  68. GRB 070520B: Swift/UVOT Upper Limits
  69. GRB 070520A: Subaru Observations
  70. GRB 070521, Swift-BAT refined analysis
  71. GRB 070520A: Swift UVOT Upper Limits
  72. GRB 070520B: Swift-XRT refined analysis
  73. GRB 070521: optical limit by Pi of the Sky
  74. GRB070521: P200 Observations
  75. GRB070521 : Faulkes Telescope North Observations
  76. GRB 070521: TAROT La Silla observatory optical observations
  77. GRB070521: Bright SDSS Galaxy Near XRT Error Circle
  78. GRB070521 - SDSS Pre-Burst Observations
  79. GRB 070521: Swift detection of a burst
  80. GRB 070520A: MITSuME Akeno optical upper limits
  81. GRB 070520B, Swift-BAT refined analysis
  82. GRB 070520A, Swift-BAT refined analysis
  83. GRB 070520A: Swift-XRT refined analysis
  84. GRB 070518: TNG observations
  85. GRB 070520B: Swift detection of a burst
  86. GRB 070520: Xinglong EST optical Upper Limit
  87. GRB 070520: Swift detection of a burst
  88. VLA observation of GRB 070518
  89. GRB 070518: Swift-XRT refined analysis
  90. GRB 070517: Gemini optical imaging
  91. GRB070518: UVOT refined analysis
  92. GRB070518: OSN observation
  93. GRB 070518, Swift-BAT refined analysis
  94. GRB 070518: OT confirmed form Xinglong TNT observation
  95. GRB 070518: Swift detection of a burst with optical afterglow
  96. GRB070517: Swift-XRT Refined Analysis
  97. GRB 070517, Swift-BAT refined analysis
  98. GRB 070517: Optical search
  99. GRB 070517: Swift detection of a burst
  100. GRB 070509: objects inside XRT error circle

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