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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"

32509 results found.

  1. GRB 071010B: Keck/LRIS Spectroscopy
  2. GRB 071011, Swift-BAT refined analysis
  3. GRB 071010B: Gemini Spectroscopic Observations
  4. GRB 071011: Early Super-LOTIS Observations
  5. GRB 071011: NAYUTA Optical Observation
  6. GRB 071010A: Continued Keck Imaging
  7. GRB 071010B: Bright OT confirmed with TLS
  8. Optical Observation: GRB 071010
  9. Optical observations: GRB 071010A
  10. Konus-Wind observation of GRB 071010B
  11. GRB071010B: Swift/XRT detection
  12. GRB 071010B, Swift-BAT refined analysis
  13. GRB 071010A: bright NIR afterglow
  14. GRB 071006, Swift-BAT refined analysis
  15. GRB071008: optical observations
  16. GRB 071010B possible optical transient
  17. GRB 071010A: Keck/LRIS Photometry
  18. GRB 071010: Swift-XRT observation
  19. GRB 071008, Swift-BAT refined analysis
  20. GRB 071010, Swift-BAT refined analysis
  21. Konus-Wind observation of GRB 071006
  22. GRB071008: Swift-XRT observation
  23. GRB 071010 REM NIR observations
  24. GRB 071010: Keck/LRIS Spectroscopy
  25. GRB 071010: Rapid PROMPT Detections
  26. GRB 071010: Keck Observations of the Afterglow
  27. GRB071008: IAC80 observation
  28. GRB 071003: XRT refined analysis
  29. GRB070920A: MAGIC telescope GeV observation
  30. Radio detection of GRB 071003 with the VLA
  31. GRB 070810B: further XRT analysis
  32. GRB 071003: VLT spectroscopy
  33. GRB 071003: Keck spectroscopy
  34. Konus-Wind observation of GRB 071003
  35. GRB071003: Faulkes Telescope North observations
  36. GRB 071003: Possible rebrightening
  37. GRB 071003 : Lulin R-band observations
  38. GRB 071003: Swift XRT position
  39. GRB 071003: OA power-law decay indices from KAIT
  40. GRB 071003: Keck HIRES spectroscopy
  41. GRB 071003, Swift-BAT refined analysis
  42. GRB 071003: MARGE Observations
  43. GRB 071003 Optical observations
  44. GRB 071003: P60 Confirmation of Optical Afterglow
  45. GRB 071003: KAIT optical afterglow observations
  46. GRB 070714B: host galaxy spectroscopic redshift
  47. GRB 071001: Swift-XRT Team refined analysis
  48. GRB 071001, Swift-BAT refined analysis
  49. Faulkes Telescope South observations of GRB 071001
  50. VLA observation of GRB 070923
  51. Disregard the Swift-XRT Notices today
  52. GRB 070911, SMARTS optical/IR afterglow observations
  53. GRB070925: Swift-XRT Afterglow confirmation
  54. GRB 070925: Gemini South Imaging
  55. GRB070925: Swift-XRT Position
  56. Update on Swift Status
  57. GRB 070920B: ROTSE-III Early Optical Limits
  58. Recent SGR1806-20 Activity
  59. GRB 070923, Swift-BAT refined analysis
  60. GRB 070920B: XRT observations
  61. GRB 070923: Galaxies within BAT localization
  62. GRB 070917: Suzaku/WAM observation of the prompt emission
  63. INTEGRAL ToO observations of SGR1806-20
  64. GRB 070920b, SMARTS optical observation
  65. GRB 070917: Confirmation of the X-ray afterglow
  66. GRB 070920b: LCO optical observations
  67. GRB 070920B, Swift-BAT refined analysis
  68. GRB 070911: Swift/BAT and Suzaku/WAM joint spectral analysis
  69. GRB 070920, Swift-BAT refined analysis
  70. SGR1806-20: Swift-BAT detection of enhanced activity
  71. GRB070917: Confirmation of optical afterglow
  72. GRB920925C: search for host galaxy
  73. GRB070917: optical observations
  74. GRB 070917: P60 Observations
  75. Konus-Wind observation of GRB 070917
  76. Swift Status and XRT Calibration Uncertainties
  77. GRB 070917: Swift-XRT observations
  78. GRB 070917: KAIT optical limits
  79. GRB 070917: MITSuME Akeno Ic upper limit
  80. GRB 070917: R band observations
  81. GRB 070917, Swift-BAT refined analysis
  82. GRB 070911: Suzaku WAM observation of the prompt emission
  83. GRB 070913: Swift-XRT detection of the possible X-ray afterglow
  84. GRB 070809: The Swift evidence for the SHB nature of this burst
  85. GRB 070913: Swift-BAT refined analysis
  86. GRB 070913: Corrected BAT position
  87. GRB 070913: SMARTS optical/IR observations
  88. GRB 070911: PAIRITEL IR Observations
  89. GRB 070911: Swift XRT refined analysis
  90. GRB 070911, Swift-BAT refined analysis
  91. IPN search for a GRB associated with TAROT transient on August 31
  92. Intense burst from SGR 1806-20 detected on September 7
  93. GRB 070809: Confirmation of optical transient
  94. Observations of possible TAROT GRB transient near IC 4779
  95. GRB 070810b: Image Subtraction of Multiple Keck Observations
  96. Las Campanas observations of possible TAROT GRB transient near IC
  97. Konus-Wind observation of GRB 070824
  98. Konus-Wind observation of very bright GRB 070821
  99. GRB 070731: Swift/UVOT Upper Limit
  100. GRB 070805: UVOT afterglow candidate retraction

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