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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"

38654 results found.

  1. GRB 071010B: Keck/LRIS Photometry
  2. VLA detection of radio afterglow of GRB 071010B
  3. VLA non-detection of GRB 071011
  4. GRB 071013: Optical observations
  5. GRB 071013: optical observations at NOT
  6. GRB071013: optical limit
  7. GRB071010B, BVRcIc field calibration
  8. GRB 20071013: Xinglong TNT optical Upper Limit
  9. GRB 071013: Swift detection of a burst
  10. GRB 071010C Swift-BAT detection of a burst
  11. GRB 071011: Optical Limit after 13.95hrs
  12. GRB 071011: Xinglong TNT Optical afterglow observations
  13. GRB 071010B correction to GCN 6892 optical observations
  14. GRB 071011: Swift-XRT refined analysis
  15. VLA non-detection of GRB 071010A
  16. GRB 071011: NAYUTA Optical Observation, correction to GCN6886
  17. GRB 071011, Optical afterglow
  18. GRB 071010B: Optical Detection
  19. GRB 071011: Kanazawa Optical limits
  20. GRB 071011: P60 Optical Afterglow Candidate
  21. GRB 071011: MARGE Optical Limits
  22. GRB 071010B: Super-LOTIS upper limit
  23. GRB 071010B optical photometry
  24. GRB 071011: XRT afterglow detection
  25. GRB 071010B: Keck/LRIS Spectroscopy
  26. GRB 071010B: Gemini Spectroscopic Observations
  27. GRB 071011: Early Super-LOTIS Observations
  28. GRB 071011: NAYUTA Optical Observation
  29. GRB 071010A: Continued Keck Imaging
  30. GRB 071010B: Bright OT confirmed with TLS
  31. GRB 071011: Swift detection of a burst
  32. Optical Observation: GRB 071010
  33. Optical observations: GRB 071010A
  34. Konus-Wind observation of GRB 071010B
  35. GRB071010B: Swift/XRT detection
  36. GRB 071010B, Swift-BAT refined analysis
  37. GRB 071010A: bright NIR afterglow
  38. GRB 071006, Swift-BAT refined analysis
  39. GRB071008: optical observations
  40. GRB 071010B: Swift detection of a burst
  41. GRB 071010: Swift-XRT observation
  42. Konus-Wind observation of GRB 071006
  43. GRB071008: Swift-XRT observation
  44. GRB 071010 REM NIR observations
  45. GRB 071010: Keck/LRIS Spectroscopy
  46. GRB 071010: Swift detection of a burst
  47. GRB 071006 Swift-BAT detection of a burst
  48. GRB071008: IAC80 observation
  49. GRB 071008: Swift detection of a burst
  50. GRB 071003: XRT refined analysis
  51. GRB070920A: MAGIC telescope GeV observation
  52. Radio detection of GRB 071003 with the VLA
  53. GRB 070810B: further XRT analysis
  54. GRB 071003: VLT spectroscopy
  55. GRB 071003: Keck spectroscopy
  56. Konus-Wind observation of GRB 071003
  57. GRB 071003: Possible rebrightening
  58. GRB 071003 : Lulin R-band observations
  59. GRB 071003: Swift XRT position
  60. GRB 071003: OA power-law decay indices from KAIT
  61. GRB 071003: Keck HIRES spectroscopy
  62. GRB 071003: MARGE Observations
  63. GRB 071003 Optical observations
  64. GRB 071003: P60 Confirmation of Optical Afterglow
  65. GRB 071003: KAIT optical afterglow observations
  66. GRB 071003: Swift detection of a bright burst
  67. GRB 070714B: host galaxy spectroscopic redshift
  68. GRB 071001: Swift-XRT Team refined analysis
  69. Faulkes Telescope South observations of GRB 071001
  70. GRB 071001: Swift detection of a burst
  71. VLA observation of GRB 070923
  72. GRB 070911, SMARTS optical/IR afterglow observations
  73. GRB070925: Swift-XRT Afterglow confirmation
  74. GRB 070925: Gemini South Imaging
  75. GRB070925: Swift-XRT Position
  76. Update on Swift Status
  77. GRB 070920B: ROTSE-III Early Optical Limits
  78. GRB 070925: a long GRB detected by INTEGRAL
  79. Recent SGR1806-20 Activity
  80. GRB 070920B: XRT observations
  81. GRB 070923: Swift detection of a short hard burst
  82. GRB 070917: Suzaku/WAM observation of the prompt emission
  83. INTEGRAL ToO observations of SGR1806-20
  84. GRB 070920b, SMARTS optical observation
  85. GRB 070917: Confirmation of the X-ray afterglow
  86. GRB 070920b: LCO optical observations
  87. GRB 070911: Swift/BAT and Suzaku/WAM joint spectral analysis
  88. GRB 070920B: Swift detection of a burst
  89. GRB 070920: Swift detection of a burst
  90. SGR1806-20: Swift-BAT detection of enhanced activity
  91. GRB070917: Confirmation of optical afterglow
  92. GRB920925C: search for host galaxy
  93. GRB070917: optical observations
  94. GRB 070917: P60 Observations
  95. Konus-Wind observation of GRB 070917
  96. Swift Status and XRT Calibration Uncertainties
  97. GRB 070917: Swift-XRT observations
  98. GRB 070917: KAIT optical limits
  99. GRB 070917: MITSuME Akeno Ic upper limit
  100. GRB 070917: R band observations

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