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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"

23572 results found.

  1. Opticall follow-ups for the X-ray transient in NGC 2770
  2. Optical Spectroscopy of the Transient in NGC 2770
  3. Early OT detection of XRF in NGC 2770 in Asiago frames
  4. Bright X-ray transient / possible XRF in NGC 2770: TNG R imaging
  5. Bright X-ray Transient in NGC 2770 - A low-luminosity XRF?
  6. GRB 071227: Suzaku WAM observation of the prompt emission
  7. Further Swift-BAT analysis of GRB 071227
  8. Konus-Wind observation of GRB 071227
  9. GRB 071227: Magellan redshift confirmation
  10. GRB 071227: Magellan observations
  11. Swift-BAT refined analysis of short GRB 071227
  12. GRB 071227: Swift detection of a burst
  13. GRB 070429B: Possible UVOT Detection of an Optical Afterglow
  14. GRB 071208?: Swift detection of a possible burst
  15. GRB 071125: Suzaku WAM observation of the prompt emission
  16. GRB 070429B: Probable host galaxy and redshift
  17. GRB 071129, Swift-BAT refined analysis
  18. GRB 071129: Swift detection of a burst
  19. Konus-Wind and Konus-A observations of GRB 071125
  20. IPN triangulation of very bright GRB 071125
  21. GRB071122: Swift/UVOT Observations
  22. GRB071104: NIR Afterglow Candidate at TNG
  23. GRB 071122: MASTER optical observation
  24. GRB 071122, Swift-BAT refined analysis
  25. GRB 071122 Swift-XRT refined analysis
  26. GRB 071122: Swift detection of a burst
  27. GRB071118 MITSuME OAO optical observation
  28. Swift/UVOT observations of GRB071118
  29. Konus-Wind and Konus-A observations of GRB 071117
  30. GRB 071118, Swift-BAT refined analysis
  31. GRB 071117: TAROT La Silla observatory optical observations
  32. GRB 071118: Swift detection of a burst
  33. GRB 071117, Swift-BAT refined analysis
  34. GRB 071117: Swift detection of a bright burst
  35. Swift detection of MXB 0656-072
  36. GRB 071112C: Optical and NIR data observed with KANATA
  37. GRB071112C: Errata of MITSuME Ic band photometry
  38. GRB 071112C: emission lines and refined VLT redshift
  39. GRB 071112B: 2nd epoch of Magellan i-band imaging
  40. GRB 071112C : Second Epoch Lulin R-band observations
  41. GRB071112C MITSuME Okayama Optical Observation
  42. GRB 071112C: Swift-BAT refined analysis
  43. GRB 071112C: Swift XRT refined analysis
  44. Swift UVOT upper limits of GRB071112B
  45. GRB 071112C: VLT redshift
  46. GRB 071112B: Swift-XRT preliminary analysis
  47. GRB 071112B, Swift-BAT partial refined analysis of the SHB
  48. GRB 071112C : Lulin R-band observation
  49. GRB 071112C: RTT150 optical observations
  50. GRB 071112C: TAROT Calern observatory optical observations
  51. GRB071112C Xinglong_TNT_and_EST_afterglow observations
  52. GRB 071112C: Optical and NIR afterglows observed with KANATA
  53. GRB 071112C: ROTSE-III Confirmation of Optical Counterpart
  54. GRB 071112C: Swift detection of a burst with an optical counterpart
  55. GRB 071112B: Swift detection of a short hard burst
  56. GRB 071112: Swift detection of a possible burst
  57. Swift/UVOT initial analysis of GRB071109
  58. GRB 071109: further Swift-XRT analysis
  59. GRB 071109: TAROT Calern observatory optical observations
  60. GRB 071109: Swift-XRT possible X-ray counterpart
  61. GRB 071109: A long GRB detected by INTEGRAL
  62. GRB 071104: Gamma Ray Burst Localization by SuperAGILE
  63. GRB 071101, Swift-BAT refined analysis
  64. GRB071101: Optical and NIR upper limits by KANATA
  65. GRB0711101: Two new source from Xinglong TNT observation
  66. GRB 071101: TAROT Calern observatory optical observations
  67. GRB071101 LOAO B,V,R,I observation
  68. GRB 071101: Swift detection of a burst
  69. GRB 071031, Swift-BAT refined analysis
  70. GRB 071031: Swift/UVOT detection of afterglow
  71. GRB 071031: Swift-XRT Team refined analysis
  72. GRB 071020: MITSuME Akeno optical observations
  73. GRB071031: Rapid PROMPT Detections
  74. GRB 071031: Swift detection of a burst with an optical counterpart
  75. GRB071028: Xinglong EST V-band upper limit
  76. GRB 071028, Swift-BAT refined analysis
  77. GRB 071028: Swift detection of a burst
  78. GRB 071003: Infrared Photometry with Keck Adaptive Optics
  79. GRB071021: MARGE Optical Limits
  80. GRB 071025 Milagro GeV/TeV Observations
  81. GRB071025: Xinglong TNT I-band upper limit
  82. GRB 060602A: host redshift
  83. GRB 071025, Swift-BAT refined analysis
  84. GRB 071025: Early Super-LOTIS Observations
  85. GRB 071025: R/I-band update
  86. GRB 071025: I-detection, R-dropout?
  87. GRB 071020: BTA spectroscopy
  88. GRB 071021: (Relatively shallow) IR non-detections; motivation for optical spectroscopy
  89. GRB071021: MITSuME Okayama Optical Upper Limits
  90. GRB 071021: Magellan i-band observation
  91. GRB 071021: correction to GCNC 6968
  92. GRB 071020: Fading slowly?
  93. GRB 071010B: Fading quickly
  94. GRB 071021: optical and NIR observations
  95. GRB 071021, Swift-BAT refined analysis
  96. GRB071018: 2nd epoch obsevations of Xinglong TNT
  97. GRB 071021: Xinglong TNT optical Upper Limit
  98. GRB 071021 : Lulin R-band limit
  99. Konus-Wind observation of GRB 071020
  100. GRB 071021: Faulkes Telescope South optical candidate

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