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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"
  1. GRB080310: Super-LOTIS suggestion of brightening
  2. GRB 080310, SMARTS optical/IR afterglow observations
  3. GRB 080310: REM observations
  4. GRB 080310: Magellan redshift
  5. GRB 080310 afterglow candidate (correction to UT time)
  6. GRB 080310: Swift detection of a burst with optical afterglow
  7. GRB 080310 afterglow candidate
  8. GRB080229, optical upper limit (Correction)
  9. GRB080307, optical upper limit
  10. GRB080307 BOAO optical afterglow observation - detection of a possible OT
  11. GRB080229, optical upper limit
  12. GRB 080307: Swift-XRT Team refined analysis
  13. GRB 080307: Swift/UVOT Upper Limits
  14. GRB 080307: Early RAPTOR Limits
  15. GRB 080307, Swift-BAT refined analysis
  16. GRB080307 - SDSS Pre-Burst Observations
  17. GRB 080307: TNT optical observation
  18. GRB080307: Optical upper limits
  19. GRB 080307: Gemini-N i-band observations - candidate afterglow
  20. GRB 080307: BOAO imaging - retraction and new limit
  21. GRB 080307: retraction of UVOT candidate
  22. GRB 080307: Enhanced Swift-XRT position
  23. GRB 080307, Preliminary Swift-BAT refined analysis
  24. GRB 080307 : BOAO optical afterglow observation
  25. GRB 080307: Optical observation with DMC/KANATA
  26. GRB 080307: Swift detection of a burst
  27. VLA possible radio detection of GRB 080229
  28. GRB 080303: Swift/UVOT follow-up of afterglow detection
  29. GRB 080303, Swift-BAT refined analysis
  30. GRB 080303: Rapid PROMPT Detections
  31. GRB080303: Swift XRT refined analysis
  32. GRB 080303: Enhanced Swift-XRT position
  33. Swift UVOT observations of GRB080229B
  34. GRB080229B: Swift XRT afterglow observation
  35. GRB 080303A: Faulkes Telescope South optical afterglow observations
  36. GRB 080303
  37. GRB 080303: Swift detection of a burst with optical afterglow
  38. GRB 080303: REM NIR afterglow candidate
  39. GRB 080303A: ROTSE-III Optical Limits
  40. GRB 080229: I-band observations from OSN
  41. GRB 080229: VLT NIR observations
  42. GRB080229: Swift XRT refined analysis
  43. GRB 080229: TNG NIR observations
  44. GRB 080229: Deep Gemini/GMOS optical observations
  45. GRB 080229: Enhanced Swift-XRT position
  46. GRB 080229: REM NIR observations
  47. GRB080229: Possible optical afterglow
  48. GRB 080229B: Gamma Ray Burst Localization by SuperAGILE
  49. UVOT analysis for GRB080229
  50. GRB 080229, Swift-BAT refined analysis
  51. GRB 080229: Faulkes Telescope South optical limit
  52. GRB 080229A: ROTSE-III Optical Limits
  53. GRB 080229: Swift detection of a bright burst
  54. Early optical shallow decay in GRB 071112C
  55. GRB080207: optical observations
  56. GRB080205: optical observations
  57. GRB080211: optical observations
  58. XRF 080109/SN2008D : GMRT upper limit at 1.28 GHz
  59. GRB 071010B : Early optical brightening detected by TAOS
  60. Swift-XRT improved positions, and new redshift limits.
  61. ESO optical and NIR observations of GRB 080218B
  62. GRB 080204: Suzaku WAM observation of the prompt emission
  63. GRB 080218B, Swift-BAT refined analysis
  64. GRB 080218B: Swift-XRT refined analysis
  65. Swift/UVOT observations of GRB080218B
  66. GRB 080218B: REM NIR early upper limits
  67. GRB 080212: Mount Abu NIR observations
  68. GRB 080218B: Enhanced Swift-XRT position
  69. GRB 080218B: GROND upper limits
  70. GRB 080218b, SMARTS optical/IR limits
  71. GRB 080218A, Swift-BAT refined analysis
  72. GRB080218B: Watcher prompt limit
  73. GRB 080211: Suzaku WAM observation of the prompt emission
  74. GRB 080218B: Swift detection of a burst
  75. GRB 080218: Swift detection of a burst
  76. Swift-XRT and UVOT observations of the IPN burst GRB 080211
  77. GRB 080212: VLT optical rapid decay
  78. GRB 080212: REM refined analysis
  79. Konus-Wind observation of GRB 080211
  80. VLA radio upper limit on GRB 080212
  81. Swift/UVOT refined analysis of GRB080212
  82. GRB 080212, Swift-BAT refined analysis
  83. GRB080212: Optical afterglow candidate observed by MITSuME Telescope
  84. GRB 080212: Gemini-South optical observations
  85. GRB 080212: GROND detects afterglow
  86. GRB 080212: REM NIR afterglow?
  87. GRB 080212: optical observations
  88. GRB 080212: Enhanced Swift-XRT position
  89. GRB 080212: Swift-XRT Team refined analysis
  90. GRB 080210: Keck photometry
  91. VLA non-detection of GRB 080210
  92. GRB 080212: Swift detection of a burst
  93. IPN localization of GRB 080211
  94. GRB 080212: DSS/2MASS Galaxy at XRT position
  95. GRB 080207: VLT NIR early upper limits
  96. GRB 080210: Swift/UVOT Refined Analysis
  97. GRB 080207: optical observations.
  98. GRB 080210: Hobby-Eberly Telescope Absorption Spectroscopy
  99. GRB 080210, Swift-BAT refined analysis
  100. GRB 080210: Super-LOTIS observations

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