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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').
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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"
  1. GRB 071010B: TLS 2nd Epoch, refined analysis
  2. GRB 071013: TLS Upper Limit
  3. Correction to GCN circular no. # 6915 for GRB 071010B
  4. VLA detection of radio afterglow of GRB 071010B
  5. VLA non-detection of GRB 071011
  6. GRB 071013: Optical observations
  7. GRB 071013: optical observations at NOT
  8. GRB 071013, Swift-BAT refined analysis
  9. GRB071013: optical limit
  10. GRB071010B, BVRcIc field calibration
  11. GRB 20071013: Xinglong TNT optical Upper Limit
  12. GRB 071013: Swift detection of a burst
  13. GRB 071010C Swift-BAT detection of a burst
  14. GRB 071011: Optical Limit after 13.95hrs
  15. GRB 071011: Xinglong TNT Optical afterglow observations
  16. GRB 071010B correction to GCN 6892 optical observations
  17. GRB 071011: Swift-XRT refined analysis
  18. VLA non-detection of GRB 071010A
  19. GRB 071011: NAYUTA Optical Observation, correction to GCN6886
  20. GRB 071011, Optical afterglow
  21. GRB 071011: Confirmation of P60 optical afterglow
  22. GRB 071010B: Optical Detection
  23. GRB 071011: Kanazawa Optical limits
  24. GRB 071011: P60 Optical Afterglow Candidate
  25. GRB 071011: MARGE Optical Limits
  26. GRB 071010B: Super-LOTIS upper limit
  27. GRB 071010B optical photometry
  28. GRB 071011: XRT afterglow detection
  29. GRB 071010B: Keck/LRIS Spectroscopy
  30. GRB 071011, Swift-BAT refined analysis
  31. GRB 071010B: Gemini Spectroscopic Observations
  32. GRB 071011: Early Super-LOTIS Observations
  33. GRB 071011: NAYUTA Optical Observation
  34. GRB 071010A: Continued Keck Imaging
  35. GRB 071010B: Bright OT confirmed with TLS
  36. GRB 071011: Optical afterglow candidate
  37. GRB 071011: Swift detection of a burst
  38. Optical Observation: GRB 071010
  39. Optical observations: GRB 071010A
  40. Konus-Wind observation of GRB 071010B
  41. GRB071010B: Swift/XRT detection
  42. GRB 071010B, Swift-BAT refined analysis
  43. GRB 071010A: bright NIR afterglow
  44. GRB 071006, Swift-BAT refined analysis
  45. GRB071008: optical observations
  46. GRB 071010B possible optical transient
  47. GRB 071010A: Keck/LRIS Photometry
  48. GRB 071010B: Swift detection of a burst
  49. GRB 071010: Swift-XRT observation
  50. GRB 071008, Swift-BAT refined analysis
  51. GRB 071010, Swift-BAT refined analysis
  52. Konus-Wind observation of GRB 071006
  53. GRB071008: Swift-XRT observation
  54. GRB 071010 REM NIR observations
  55. GRB 071010: Keck/LRIS Spectroscopy
  56. GRB 071010: TAROT La Silla observatory photometry of the afterglow
  57. GRB 071010: Rapid PROMPT Detections
  58. GRB 071010: Keck Observations of the Afterglow
  59. GRB 071010: TAROT La Silla observatory detection of the afterglow
  60. GRB 071010: Swift detection of a burst
  61. GRB 071006 Swift-BAT detection of a burst
  62. GRB071008: IAC80 observation
  63. GRB 071008: Swift detection of a burst
  64. GRB 071003: XRT refined analysis
  65. GRB070920A: MAGIC telescope GeV observation
  66. Radio detection of GRB 071003 with the VLA
  67. GRB 070810B: further XRT analysis
  68. GRB 071003: VLT spectroscopy
  69. GRB 071003: Keck spectroscopy
  70. Konus-Wind observation of GRB 071003
  71. GRB071003: Faulkes Telescope North observations
  72. GRB 071003: Possible rebrightening
  73. GRB 071003 : Lulin R-band observations
  74. GRB 071003: Swift XRT position
  75. GRB 071003: OA power-law decay indices from KAIT
  76. GRB 071003: Keck HIRES spectroscopy
  77. GRB 071003, Swift-BAT refined analysis
  78. GRB 071003: MARGE Observations
  79. GRB 071003 Optical observations
  80. GRB 071003: P60 Confirmation of Optical Afterglow
  81. GRB 071003: KAIT optical afterglow observations
  82. GRB 071003: Swift detection of a bright burst
  83. GRB 070714B: host galaxy spectroscopic redshift
  84. GRB 071001: Swift-XRT Team refined analysis
  85. GRB 071001, Swift-BAT refined analysis
  86. Faulkes Telescope South observations of GRB 071001
  87. GRB 071001: Swift detection of a burst
  88. VLA observation of GRB 070923
  89. Disregard the Swift-XRT Notices today
  90. GRB 070911, SMARTS optical/IR afterglow observations
  91. GRB070925: Swift-XRT Afterglow confirmation
  92. GRB 070925: Gemini South Imaging
  93. GRB070925: Swift-XRT Position
  94. Update on Swift Status
  95. GRB 070920B: ROTSE-III Early Optical Limits
  96. GRB 070925: a long GRB detected by INTEGRAL
  97. Recent SGR1806-20 Activity
  98. GRB 070923, Swift-BAT refined analysis
  99. GRB 070920B: XRT observations
  100. GRB 070923: Galaxies within BAT localization

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