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"

39059 results found.

  1. GRB 070521: Keck imaging
  2. GROND upper limits of GRB 070521
  3. GRB 070521 Milagro GeV/TeV Observations
  4. GRB 070520B: SARA upper limit
  5. GRB 070520A: SARA upper limit
  6. GRB 070521: SARA upper limit
  7. GRB 070521: Subaru observations and possible host detection
  8. GRB 070520B: Swift/UVOT Upper Limits
  9. GRB 070520A: Subaru Observations
  10. GRB 070521, Swift-BAT refined analysis
  11. GRB 070520A: Swift UVOT Upper Limits
  12. GRB 070520B: Swift-XRT refined analysis
  13. GRB 070521: optical limit by Pi of the Sky
  14. GRB070521 : Faulkes Telescope North Observations
  15. GRB 070521: TAROT La Silla observatory optical observations
  16. GRB070521: Bright SDSS Galaxy Near XRT Error Circle
  17. GRB070521 - SDSS Pre-Burst Observations
  18. GRB 070521: Swift detection of a burst
  19. GRB 070520A: MITSuME Akeno optical upper limits
  20. GRB 070520B, Swift-BAT refined analysis
  21. GRB 070520A, Swift-BAT refined analysis
  22. GRB 070520A: Swift-XRT refined analysis
  23. GRB 070518: TNG observations
  24. GRB 070520B: Swift detection of a burst
  25. GRB 070520: Xinglong EST optical Upper Limit
  26. GRB 070520: Swift detection of a burst
  27. VLA observation of GRB 070518
  28. GRB 070518: Swift-XRT refined analysis
  29. GRB 070517: Gemini optical imaging
  30. GRB070518: OSN observation
  31. GRB 070518, Swift-BAT refined analysis
  32. GRB 070518: OT confirmed form Xinglong TNT observation
  33. GRB 070518: Swift detection of a burst with optical afterglow
  34. GRB 070517, Swift-BAT refined analysis
  35. GRB 070517: Optical search
  36. GRB 070517: Swift detection of a burst
  37. GRB 070509: objects inside XRT error circle
  38. GRB 070512: pseudo-z ~ 1.39 from prompt emission spectrum
  39. GRB 070512: IPN localization and Konus spectrum of a bright burst
  40. GRB070419A: optical observations
  41. GRB 070419A, Deep LBT photometry
  42. GRB 070508: pseudo-z from 4 different spectral analyses
  43. GRB 070509: Swift/UVOT Upper Limits
  44. Konus-Wind and Konus-A observation of GRB 070508
  45. Swift-BAT trigger 278987 is not a GRB
  46. GRB 070510: Swift detection of a possible burst
  47. GRB070509: Swift-XRT Refined Analysis
  48. GRB 070508: OA fading and tentative redshift
  49. GRB 070509, Swift-BAT refined analysis
  50. GRB 070508: Suzaku/WAM observation of the prompt emission
  51. GRB 070509: REM observations
  52. GRB 070509: Swift detection of a burst
  53. GRB 070509: ROTSE-III Optical Limits
  54. GRB070508: Swift/UVOT Observations
  55. GRB 070508, SMARTS optical afterglow observation
  56. GRB 070508, Swift-BAT refined analysis
  57. GRB 070508: Multicolor optical observations and possible redshift limit
  58. GRB 070508: Swift-XRT refined analysis
  59. GRB 070508: Optical observation limiting magnitude
  60. GRB 070508: Optical afterglow detection
  61. GRB 070508: REM observations
  62. GRB 070508: TAROT La Silla observatory optical observations
  63. GRB 070508: Swift detection of an intense burst with an optical counterpart
  64. Swift-BAT trigger 278809 is not a GRB
  65. GRB 070507: Swift detection of a possible cosmic ray shower event or a possible burst
  66. GRB 070506: VLT redshift
  67. GRB070506: Swift XRT refined analysis
  68. GRB 070506, Swift-BAT Refined Analysis
  69. GRB 070506: Swift detection of a burst with optical afterglow
  70. GRB 070412, deep LBT imaging
  71. GRB 070429A: Swift XRT further analysis
  72. GRB070429B: VLT observations
  73. GRB 070429A: optical observations
  74. GRB 070309: Swift-XRT afterglow confirmation
  75. GRB070429B: possible host galaxy detection
  76. VLA observation of GRB 070429B
  77. Swift/UVOT observations of GRB070429B
  78. GRB 070429B, Swift-BAT refined analysis
  79. Swift/UVOT observations of GRB070429A
  80. GRB 070429A: Swift XRT refined analysis
  81. GRB 070429A, Swift-BAT refined analysis
  82. GRB 070429A: optical and NIR observations
  83. GRB 070429B: Swift XRT refined analysis
  84. GRB 070429B: ROTSE-III Optical Limits
  85. GRB 070429B: Swift detection of a short burst
  86. GRB 070429: What's the temperature?
  87. GRB 070429: ROTSE-III Optical Limits
  88. GRB 070429: Swift detection of a burst
  89. GRB 070427, Swift-BAT Refined Analysis
  90. LT monitoring of GRB070412
  91. GRB 070427: Swift detection of a burst
  92. GRB 070411, further deep LBT photometry
  93. GRB 070411: Late-time Keck imaging
  94. GRB 070411 : Planned XMM-Newton observation
  95. GRB070419B: Suzaku WAM observation of the prompt emission
  96. GRB 070420, SMARTS optical/IR afterglow observations
  97. GRB 070411, deep LBT photometry
  98. GRB 070420: pseudo-z~1.56 from spectral parameters of the prompt
  99. Konus-Wind observation of GRB 070420
  100. GRB 070411: break in the optical light curve

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Looking for U.S. government information and services? Visit USA.gov