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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"

27478 results found.

  1. Errartum: VLA upper limit on GRB 080507
  2. VLA upper limit on GRB 080705
  3. GRB 080514B : redshift estimation
  4. GRB 080514B: KPNO 4m IR observations
  5. GRB 080514B: slow fading behaviour ?
  6. GRB 080514B: Swift-XRT analysis
  7. GRB 080514B, GROND observations
  8. GRB 080515: Swift detection of a burst
  9. GRB 080514B: Afterglow candidate
  10. GRB 080430
  11. GRB 080514B: possible AGILE detection at E>50 MeV
  12. Swift detection of a possible galactic transient
  13. GRB080514: REM NIR & Optical Observations
  14. GRB 080319B: Further HST observations and underlying host
  15. GRB 080506: NAYUTA Optical Observation
  16. GRB 080507: Swift XRT analysis confirms the X-ray afterglow
  17. GRB 080507: Keck photometry
  18. GRB 080507: E Pur Si Muove!
  19. GRB 080503: Chandra Observation of X-ray Rebrightening or Flattening
  20. GRB 080503: Hubble Space Telescope Imaging
  21. GRB080507: Swift/UVOT followup observations
  22. GRB 080507: Optical Afterglow
  23. GRB 080507: Swift-XRT position of a possible afterglow
  24. GRB 080506: VLA radio upper limit
  25. GRB 080507: GRB localization by SuperAGILE
  26. GRB 080506: TLS 2nd Epoch - possible light curve break
  27. GRB 080506: Swift XRT refined analysis
  28. GRB080506: Swift/UVOT observations
  29. GRB 080506: TLS afterglow detection in VRIZ
  30. GRB 080506: Enhanced Swift-XRT position
  31. GRB 080506: Swift detection of a burst with optical afterglow
  32. GRB 080503: VLA radio upper limit
  33. GRB 080503: Slow-rise optical AG ?
  34. GRB 080430: TLS imaging one day after the GRB
  35. GRB 080503: Late-time Optical rebrightening (possible mini-SN)
  36. GRB 080503: MITSuME Ishigakijima optical upper limits
  37. GRB080503: Swift/UVOT Upper Limits
  38. GRB080503 XRT refined analysis
  39. GRB 080430
  40. GRB 080430
  41. GRB 080503: Enhanced Swift-XRT position
  42. GRB 080503: MITSuME Akeno optical upper limits
  43. GRB 080503: New candidate afterglow/host in Gemini imaging
  44. GRB 080503: Optical afterglow candidate and LRIS spectroscopy of the short burst
  45. GRB 080503: Swift detection of a short burst
  46. GRB 080411: Continued Swift Monitoring
  47. GRB 080430: Shallow decay
  48. GRB080430: RTT150 Optical Observations
  49. GRB080430: Swift/UVOT observations
  50. VLA radio upper limit on GRB 080430
  51. GRB 080430 - multicolor observations of the afterglow
  52. GRB 080430 optical observations
  53. GRB080430: optical observations
  54. GRB 080430: Hobby-Eberly Telescope Absorption Redshift
  55. GRB 080430: Swift-XRT refined analysis
  56. GRB 080430: Enhanced Swift-XRT position
  57. GRB 080430: Swift detection of a burst with optical afterglow
  58. GRB080426: Observations from CAHA
  59. GRB 080426: Swift-XRT refined analysis
  60. GRB080426: Swift/UVOT upper limits
  61. GRB 080426: Enhanced Swift-XRT position
  62. GRB 080426: Swift detection of a possibly short burst
  63. Possible GRB 080315: XRT non-detection of afterglow
  64. GRB 080320 : Faulkes Telescope North Observations
  65. GRB 080319A : Liverpool and Faulkes Telescopes Observations
  66. GRB 080420?: Swift detection of a possible short burst
  67. GRB 080413B: Rapid PROMPT Observations
  68. Swift XRT and UVOT observations of GRB080414
  69. GRB 080319B: Jet Break, Energetics, Supernova
  70. GRB 080413B: Faulkes Telescope South optical afterglow observations
  71. GRB 080413A: Liverpool Telescope and Faulkes Telescope South optical observations
  72. GRB 080413A: MOA-II optical afterglow observations
  73. GRB 080319B: Continued Gemini-N monitoring
  74. VLA radio observations of GRB 080413B
  75. VLA radio observations of GRB 080413A
  76. GRB080413B
  77. GRB 080413a, SMARTS optical/IR afterglow observations
  78. GRB 080413B: Swift XRT refined analysis
  79. GRB080413A: Swift/UVOT observations
  80. GRB 080413A: Swift-XRT refined analysis
  81. GRB 080413A: VLT/UVES redshift
  82. GRB 080413B: VLT redshift
  83. GRB080413B: REM NIR & Optical Observation
  84. GRB 080413B: GROND detection of afterglow in all bands
  85. GRB 080413B: Swift detection of a possibly short burst with optical counterpart
  86. GRB 080413A: REM detection of the NIR Afterglow
  87. GRB 080413: Enhanced Swift-XRT position
  88. GRB 080413: Swift detection of a burst with an optical afterglow
  89. GRB 080413: ROTSE-III Detection of Optical Counterpart
  90. GRB 080411: Swift/UVOT refined analysis
  91. GRB 080411: Swift-XRT Refined Analysis
  92. GRB 080411: Enhanced Swift-XRT position
  93. GRB 080411: VLT redshift
  94. GRB 080411: GROND detection of optical afterglow candidate
  95. GRB 080411: Swift detection of a bright burst
  96. GRB 080330: Swift-XRT refined position retraction
  97. GRB 080408: GROND detection of optical/NIR afterglow candidate
  98. GRB 080330 optical observations
  99. Swift/UVOT observations of GRB080409
  100. GRB 080409: Swift XRT refined analysis

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