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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

36402 results found.

  1. GRB(?)060421:MASTER optical limit
  2. GRB(?)060421 : XRT position
  3. GRB(?) 060421: Swift detection of a burst
  4. Erratum of GCN 4983 for GRB 060418 IR follow-up
  5. GRB 060418 : IR afterglow observations
  6. GRB 060418 : Lulin Optical follow-up
  7. GRB 060418: JHKs PAIRITEL Observations of Afterglow
  8. GRB 060418: Radio Observations
  9. GRB060418, BVRcIc field calibration
  10. GRB060418: Optical Observations
  11. GRB 060418: FRAM early afterglow observation
  12. GRB 060418: Refined Analysis of the Swift-BAT burst
  13. GRB060418: Swift XRT Team Refined Analysis
  14. GRB 060418, SMARTS continuing afterglow observations
  15. GRB 060418: PROMPT Detections
  16. GRB 060418, SMARTS optical/IR afterglow observations
  17. GRB060418: Magellan/MIKE Spectroscopic Redshift
  18. GRB060418 : LT optical afterglow observation
  19. GRB 060418: REM candidate afterglow
  20. GRB 060418: Swift detection of a burst with bright x-ray and optical afterglow
  21. GRB 060413: REM NIR Observations
  22. GRB 060413: Refined analysis of the Swift-BAT burst
  23. GRB 060413: Watcher UBVR observations
  24. GRB 060413: XRT refined analysis
  25. GRB 060413: No Optical Afterglow in Swift/UVOT TDRSS Data
  26. GRB 060413: Swift detection of a burst
  27. GRB060403: optical observations
  28. GRB 060403 Optical observations
  29. GRB 060403: MITSuME optical observation
  30. GRB060403: XRT refined analysis
  31. GRB 060403: Swift/UVOT upper limits
  32. GRB 060403: Refined analysis of the Swift-BAT burst
  33. GRB 060403: Swift detection of a burst
  34. GRB 060322: LNA optical limit
  35. GRB 060218SN 2006aj: optical observations at Rozhen Observatory
  36. GRB 060323 : WIDGET simultaneous optical observations
  37. GRB 060323: Early optical observation at Xinglong
  38. GRB060218, optical observations
  39. GRB 060322: Confirmation of Swift XRT afterglow
  40. GRB 060211A: optical observation
  41. GRB060323: optical limit
  42. GRB060211B: optical observation
  43. GRB060323: NOT optical observations
  44. GRB 060322: IAC80 optical observations
  45. GRB 060322: Swift XRT afterglow candidate
  46. GRB 060323: Swift/UVOT Observations
  47. GRB 060323: optical afterglow confirmed
  48. GRB060323: NOT observations
  49. GRB 060323: Optical Observations
  50. GRB 060323: Tautenburg OT candidate retraction
  51. GRB 060323: Refined analysis of the Swift-BAT burst
  52. GRB 060323: optical observations at TNG
  53. GRB 060323: Swift XRT refined analysis
  54. GRB 060323: BVRI observations at Tautenburg, aftreglow candidate
  55. GRB 060323: Swift/XRT position
  56. GRB 060322: Refined analysis of the Swift-BAT burst
  57. GRB060323 - SDSS Pre-Burst Observations
  58. GRB 060323: Swift detection of a burst with a possible optical afterglow
  59. GRB 060322: Swift-BAT detection of a 200-sec burst
  60. GRB060219: optical observation
  61. GRB060206: optical observation
  62. GRB060218/SN2006aj: optical observations
  63. GRB 060218/SN 2006aj, LNA optical observation
  64. GRB060218: Refined photometric calibration of comparison stars
  65. GRB 060319: WHT K-band candidate afterglow
  66. GRB 060319: IAC-80 optical observations
  67. GRB060319: Swift XRT refined analysis
  68. GRB 060319: Re-analysis of TNG data
  69. GRB060319: MASTER limit
  70. GRB 060319: Swift-BAT refined analysis
  71. GRB 060319 optical observations at TNG
  72. GRB060319 : Liverpool Telescope optical limit
  73. GRB060319: MASTER optical observation
  74. GRB060319 - SDSS Pre-burst Observations
  75. GRB 060319: Swift detection of a burst
  76. GRB060313: Radio Observations
  77. GRB 060313: early afterglow NIR upper limits with REM
  78. IBAS Alert n. 3221: not a GRB
  79. Konus-Wind observation of GRB 060313
  80. GRB060313: SSO 40inch Observations
  81. GRB 060313: Further analysis of the Swift-BAT bright short hard burst
  82. GRB 060313: PROMPT Observations
  83. GRB 060313: Swift/UVOT Observations
  84. GRB060313:Gemini South Observations
  85. GRB 060313: Swift-XRT team refined analysis
  86. GRB060313: optical observations of the afterglow candidate
  87. GRB 060313: Refined analysis of the Swift-BAT bright short hard burst
  88. GRB 060313, SMARTS optical counterpart?
  89. GRB 060313: Possible optical counterpart
  90. GRB 060313: Swift XRT position
  91. GRB 060313, SMARTS optical/IR observations
  92. GRB060313: optical and near infrared observations with REM
  93. GRB 060313: Swift-BAT detection of a bright short hard burst
  94. GRB060218: SARA Observations of SN2006aj
  95. GRB 060312: Refined analysis of the Swift-BAT burst
  96. GRB 060218/SN 2006aj, high resolution spectra
  97. GRB 060312: Swift XRT team refined analysis
  98. GRB060306: APO Ks-band Imaging Observations
  99. GRB 060312: ROTSE-III Optical Limits
  100. GRB 060312: Swift detection of a burst

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