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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

21267 results found.

  1. GRB 071010B: Photometry after 1.6 days
  2. GRB 071010B: Keck/LRIS Photometry
  3. GRB 071013: TLS Upper Limit
  4. VLA non-detection of GRB 071011
  5. GRB 071013: Optical observations
  6. GRB 071013: optical observations at NOT
  7. GRB 071013, Swift-BAT refined analysis
  8. GRB071010B, BVRcIc field calibration
  9. GRB 20071013: Xinglong TNT optical Upper Limit
  10. GRB 071010C Swift-BAT detection of a burst
  11. GRB 071011: Optical Limit after 13.95hrs
  12. GRB 071010B correction to GCN 6892 optical observations
  13. GRB 071011: Swift-XRT refined analysis
  14. VLA non-detection of GRB 071010A
  15. GRB 071011: NAYUTA Optical Observation, correction to GCN6886
  16. GRB 071011: Confirmation of P60 optical afterglow
  17. GRB 071010B: Optical Detection
  18. GRB 071011: Kanazawa Optical limits
  19. GRB 071011: P60 Optical Afterglow Candidate
  20. GRB 071011: MARGE Optical Limits
  21. GRB 071010B: Super-LOTIS upper limit
  22. GRB 071010B optical photometry
  23. GRB 071011: XRT afterglow detection
  24. GRB 071011: Early Super-LOTIS Observations
  25. GRB 071011: NAYUTA Optical Observation
  26. GRB 071010A: Continued Keck Imaging
  27. GRB 071010B: Bright OT confirmed with TLS
  28. Optical Observation: GRB 071010
  29. Optical observations: GRB 071010A
  30. GRB071010B: Swift/XRT detection
  31. GRB 071010A: Keck/LRIS Photometry
  32. Konus-Wind observation of GRB 071006
  33. GRB 071010 REM NIR observations
  34. GRB 071010: TAROT La Silla observatory detection of the afterglow
  35. Radio detection of GRB 071003 with the VLA
  36. Konus-Wind observation of GRB 071003
  37. GRB 071003: Possible rebrightening
  38. GRB 071003 : Lulin R-band observations
  39. GRB 071003: OA power-law decay indices from KAIT
  40. GRB 071003: P60 Confirmation of Optical Afterglow
  41. Faulkes Telescope South observations of GRB 071001
  42. GRB 071001: Swift detection of a burst
  43. VLA observation of GRB 070923
  44. GRB 070911, SMARTS optical/IR afterglow observations
  45. GRB 070925: Gemini South Imaging
  46. GRB 070920B: ROTSE-III Early Optical Limits
  47. Recent SGR1806-20 Activity
  48. GRB 070917: Suzaku/WAM observation of the prompt emission
  49. GRB 070920B: TAROT La Silla observatory optical observations
  50. GRB 070911: Swift/BAT and Suzaku/WAM joint spectral analysis
  51. GRB 070920B: NOT optical observations
  52. GRB 070920: TAROT Calern observatory optical observations
  53. SGR1806-20: Swift-BAT detection of enhanced activity
  54. GRB 070917: P60 Observations
  55. Swift Status and XRT Calibration Uncertainties
  56. GRB 070917: MITSuME Akeno Ic upper limit
  57. GRB 070917: R band observations
  58. GRB 070917, Swift-BAT refined analysis
  59. GRB 070917: Swift detection of a bright burst
  60. GRB 070911: Suzaku WAM observation of the prompt emission
  61. GRB 070913: Swift-XRT detection of the possible X-ray afterglow
  62. GRB 070913: SMARTS optical/IR observations
  63. GRB 070913: TAROT La Silla observatory optical observations
  64. GRB 070913: Swift detection of a burst
  65. GRB 070911: PAIRITEL IR Observations
  66. GRB 070911, Swift-BAT refined analysis
  67. Intense burst from SGR 1806-20 detected on September 7
  68. GRB 070809: Confirmation of optical transient
  69. Candidate Orphan GRB Optical Transient in IC 4779
  70. Las Campanas observations of possible TAROT GRB transient near IC
  71. Orphan GRB candidate in IC 4779 at TAROT La Silla observatory
  72. Konus-Wind observation of GRB 070824
  73. GRB 070824 - Combined SuperAGILE/IPN Localization
  74. Konus-Wind observation of very bright GRB 070821
  75. GRB 070731: Swift/UVOT Upper Limit
  76. GRB 070805: UVOT afterglow candidate retraction
  77. GRB 070810B : Faulkes Telescope South Observations
  78. GRB 070810A: Continued Keck Imaging
  79. GRB 070810B: Keck spectroscopy of possible host galaxies
  80. GRB070810B: Swift/UVOT Upper Limits
  81. GRB 070810B: Xinglong TNT optical Upper Limit
  82. GRB070810B: Optical observations with KANATA
  83. GRB 070809: Swift/UVOT Upper Limits
  84. VLA upper limit on the short hard burst GRB 070729
  85. No radio detection in superAGILE burst 070724B
  86. GRB 070809: Keck Imaging
  87. GRB 070810: enhanced Swift-XRT position
  88. GRB 070810: Swift/UVOT Optical Counterpart
  89. GRB 070808: Swift/UVOT upper limits
  90. GRB 070809: ROTSE-III Optical Limits
  91. GRB 070809: Swift detection of a short burst
  92. GRB 070808 : Faulkes Telescope South Observations
  93. GCN Swift XRT update position notices and enhanced position circulars
  94. GRB 070808: Swift XRT refined analysis
  95. GRB 070808: Xinglong TNT optical Upper Limit
  96. GRB070808: Optical observations with KANATA
  97. GRB070808 - SDSS Pre-Burst Observations
  98. GRB 070808: ROTSE-III Optical Limits
  99. GRB070805 XRT and UVOT afterglow candidate
  100. GRB070612A: Radio upper limit from GMRT

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