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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"
  1. GRB 070805: Swift/UVOT initial analysis
  2. GRB 070805: Swift detection of a burst
  3. UVOT observations of SAXJ1810.8-2609
  4. Swift detection of a outburst from SAX J1810.8-2609
  5. VLA non-detection of GRB 070721B
  6. GRB 070802: REM optical observations
  7. GRB 070724B: Swift-XRT afterglow confirmation
  8. GRB 070802: Swift-XRT refined analysis
  9. GRB070802: Swift/UVOT upper limits
  10. GRB 070802: Confirmation of the optical afterglow
  11. GRB 070802, Swift-BAT refined analysis
  12. GRB 070802: VLT redshift
  13. GRB 070802: refined Swift XRT position
  14. GRB 070802: V-band detection of the candidate afterglow
  15. GRB 070802: LCO I-band candidate
  16. GRB 070802: GROND J band candidate
  17. GRB 070802: LCO optical observations
  18. GRB 070802: Swift detection of a burst
  19. GRB 070731, Swift-BAT refined analysis
  20. Konus-A observation of GRB 070729
  21. Swift/UVOT detection of GRB070714B
  22. AGILE-ACS position for the SGR 1806-20 July 27 burst
  23. GRB 070724B: pseudo-z ~ 1.10 from prompt emission spectrum
  24. GRB 070729: LCO optical imaging
  25. VLA upper limit on short hard burst GRB 070714B
  26. Intense burst from SGR 1806-20 detected on July 27
  27. GRB070729: Swift/UVOT upper limits
  28. GRB 070729: Swift-XRT refined analysis
  29. GRB 070729, Swift-BAT refined analysis
  30. GRB 070729: Magellan NIR Observations
  31. GRB 070724B: P60 Observations
  32. GRB 070729: Swift detection of a short hard burst
  33. GRB 070724B: Swift/UVOT Upper limits
  34. GRB070721A: Swift/UVOT Detection of a Weak Afterglow
  35. GRB 070724B: Swift-XRT afterglow likely candidate
  36. GRB 070721A: optical observations
  37. GRB 070724A: further VLT observations
  38. GRB 070724B: Suzaku WAM observation of the prompt emission
  39. Konus-Wind observation of GRB 070724B
  40. GRB 070724B: Analysis of AGILE gamma-ray data
  41. GRB 070724B: Swift-XRT afterglow candidates
  42. GRB 070724b: First Gamma Ray Burst Localization by SuperAGILE onboard
  43. Four radio sources in Swift-XRT error box of GRB 070724
  44. GRB 070724: optical observations
  45. GRB070724: Host galaxy redshift
  46. GRB 070724: P60 and Gemini Observations
  47. GRB 060814 - Keck host detection and redshift
  48. GRB 070724: IR observations
  49. GRB 070724: Closer association with DSS source
  50. Swift/UVOT refined analysis of GRB070724
  51. GRB 070724: Swift-XRT Team refined analysis
  52. GRB 070724: Pre-Imaging Shows a Source in the XRT Error Circle
  53. Short-Hard GRB070714B: PROMPT Observations
  54. GRB 070724, Swift-BAT refined analysis of a short burst
  55. GRB 070721B: further observations and analysis
  56. GRB 070724: Swift detection of a burst
  57. GRB 070326: Detection of first burst from BAT Slew Survey (BATSS)
  58. GRB 070714B: Keck observations
  59. GRB 070721B: optical observations and proposed redshift
  60. Swift/UVOT observations of GRB070721B optical afterglow.
  61. GRB 070721B, Further Swift-BAT refined analysis
  62. Swift/UVOT Observations of GRB070721A
  63. GRB 070721B : Faulkes Telescope South observations
  64. GRB 070721B: Swift-XRT refined analysis
  65. GRB 070721A : Faulkes Telescope South optical limit
  66. GRB 070721A: Swift/XRT refined analysis
  67. GRB 070721B, Swift-BAT refined analysis
  68. GRB 070721A, Swift-BAT refined analysis
  69. GRB070721B: A bright UVOT candidate
  70. GRB 070721B: Swift detection of a burst
  71. GRB 070721: Swift detection of a possible burst
  72. GRB 070714B: Swift/BAT and Suzaku/WAM joint spectral analysis
  73. GRB 070714B : Suzaku WAM observation of the prompt emission
  74. GRB 070714A: Swift-BAT T_zero
  75. GRB070714B: TNG NIR observations
  76. Erratum : Suzaku WAM observation of GRB 070704
  77. GRB 070714A: Swift/UVOT Upper limits
  78. GRB 070714B: Swift/UVOT Upper Limits
  79. GRB 070714B: Swift-BAT spectral lag for the SHB
  80. GRB 070714B: confirmation of optical afterglow
  81. GRB 070616: No Evidence for I Band Afterglow
  82. GRB 070714A: Swift XRT refined analysis
  83. GRB070714B: Swift-XRT refined analysis
  84. GRB 070707: Swift-XRT follow-up observations
  85. GRB 070714b ("Bastille"): Optical Pre-Imaging (Clarification)
  86. GRB 070714 ("Bastille"): Optical Pre-Imaging
  87. GRB 070714B, Swift-BAT refined analysis of the short hard burst
  88. GRB 070714A, Swift-BAT refined analysis
  89. GRB 070714 : Liverpool Telescope optical counterpart ?
  90. GRB 070714: Swift detection of a bright burst, possibly short
  91. Swift detection of a possible burst (Trigger 284850)
  92. SN 2007bg - off-axis GRB?
  93. GRB 070704: RTT150 optical observations
  94. GRB 070704: Suzaku/WAM observation of the prompt emission
  95. Konus-Wind observation of GRB 070707
  96. Updated Swift/UVOT calibration
  97. GRB 070707: optical afterglow
  98. GRB 070707: object inside XRT error circle
  99. Swift/UVOT Observations of GRB070707
  100. Swift XRT observation of GRB 070707

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