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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"

18334 results found.

  1. GRB 080205: Swift/UVOT observations
  2. GRB 080205: Enhanced Swift-XRT position
  3. Swift-BAT Trigger #302454, correction of GCN notice, update on AX J1749.1-2639
  4. GRB 080130: Swift-BAT refined analysis
  5. GRB 080130: further Swift XRT observations confirm fading source
  6. GRB 080129: Swift/UVOT Refined Upper Limits
  7. Swift/UVOT observations of GRB080130
  8. GRB 080130: REM NIR observations
  9. GRB 080130(?): Swift XRT observation
  10. GRB 080129: Swift-XRT refined analysis
  11. GRB 080129: KAIT optical limits
  12. GRB 080129: TAROT La Silla observatory optical observations
  13. GRB 080129: GROND detection in all bands, and fading
  14. GRB 080129: GROND detection of the optical/NIR afterglow, and fading
  15. GRB 080129: Enhanced Swift-XRT position
  16. GRB 080129: Gemini-South Imaging Observations
  17. GRB 080129 (?): UVOT Upper Limits
  18. GRB 080121: Swift/UVOT upper limits
  19. SNe 2008D and 2007uy: Chandra Detections
  20. GRB 080121: Enhanced Swift-XRT position
  21. IPN triangulation of GRB080122
  22. GRB 080121: Nearby SDSS galaxies
  23. GRB 080123: Swift/UVOT refined analysis
  24. GRB 080123: Enhanced Swift-XRT position
  25. GRB 080123: Swift detection of a short burst
  26. GRB 080120: GROND confirmation of the optical afterglow
  27. VLA radio upper limit on GRB 080120
  28. GRB 080120: Swift-XRT refined analysis
  29. GRB080120: Swift XRT position
  30. Transient XRF 080109 / SN 2008D: Mount Abu NIR observations
  31. XRF 080109 / SN 2008D: UKIRT JHK imaging
  32. optical observations, XRT in NGC 2770
  33. Gemini-South observations of XRF 080109 / SN 2008D
  34. Swift observations of the X-ray transient in NGC 2770 (aka SN2008D)
  35. Discovery of Radio Emission from Transient in NGC 2770
  36. XRF 080109 in NGC2770: NIR observations at TNG
  37. XRB 080109/SN 2008D: Early decline in brightness and change in colors
  38. XRB 080109/SN 2008D:PAIRITEL NIR observations and t_0 from Swift
  39. Refined Swift-XRT analysis of the transient in NGC 2770
  40. Swift UVOT Observations of the X-ray transient in NGC 2770
  41. GRB 071227: optical afterglow
  42. Further Swift-BAT analysis of GRB 071227
  43. GRB 071227: Swift-XRT refined analysis
  44. GRB 071227: VLT probable redshift of the candidate host galaxy
  45. GRB071227: Swift/UVOT refined analysis
  46. GRB 071227: REM NIR and Optical observations
  47. GRB 071227: Swift detection of a burst
  48. GRB 070429B: Possible UVOT Detection of an Optical Afterglow
  49. GRB 070429B: Probable host galaxy and redshift
  50. GRB 071126: Enhanced Swift-XRT position
  51. GRB071122: Swift/UVOT Observations
  52. GRB071104: NIR Afterglow Candidate at TNG
  53. GRB 071122 Swift-XRT refined analysis
  54. GRB 071122: P60 Optical Afterglow Candidate
  55. GRB 071122: Swift detection of a burst
  56. GRB 071118: P60 Observations
  57. GRB071118 MITSuME OAO optical observation
  58. GRB 071118: Observations from OSN
  59. GRB 071117: VLT observations and probable redshift
  60. Swift/UVOT observations of GRB071118
  61. Swift XRT follow-up observations of GRB071008
  62. Swift/UVOT upper limits for GRB 071117
  63. GRB071118: Swift XRT refined analysis
  64. GRB 071117: Gemini Optical Afterglow Discovery
  65. GRB 071117: TAROT La Silla observatory optical observations
  66. GRB 071118: Swift detection of a burst
  67. GRB 071117: Gemini Observations
  68. Swift detection of MXB 0656-072
  69. GRB 071112C: Optical and NIR data observed with KANATA
  70. GRB 071112C MITSuME Akeno early optical observation
  71. GRB 071112C: SARA upper limit
  72. GRB 071112C : Second Epoch Lulin R-band observations
  73. GRB071112C MITSuME Okayama Optical Observation
  74. GRB 071112C: Swift-BAT refined analysis
  75. GRB 071112C: Swift XRT refined analysis
  76. Swift UVOT upper limits of GRB071112B
  77. GRB 071112B: Gemini Optical Imaging
  78. GRB 071112B: Swift-XRT preliminary analysis
  79. GRB 071112C : Lulin R-band observation
  80. GRB 071112C: TAROT Calern observatory optical observations
  81. Swift XRT follow-up observations of GRB071028B
  82. GRB071112C Xinglong_TNT_and_EST_afterglow observations
  83. GRB 071112C: Optical and NIR afterglows observed with KANATA
  84. GRB 071112C: Swift detection of a burst with an optical counterpart
  85. GRB 071112: Swift detection of a possible burst
  86. Swift/UVOT initial analysis of GRB071109
  87. GRB 071109: further Swift-XRT analysis
  88. GRB 071109: TAROT Calern observatory optical observations
  89. GRB 071109: Swift-XRT possible X-ray counterpart
  90. GRB 071109: A long GRB detected by INTEGRAL
  91. GRB 071104: Possible Swift UVOT Afterglow Candidate
  92. GRB 071104: Swift-XRT position
  93. Swift XRT and UVOT observations of GRB071028B
  94. GRB071101: Optical and NIR upper limits by KANATA
  95. GRB0711101: Two new source from Xinglong TNT observation
  96. GRB 071101: TAROT Calern observatory optical observations
  97. GRB071101 LOAO B,V,R,I observation
  98. GRB 071031: Swift-XRT Team refined analysis
  99. GRB 071020: MITSuME Akeno optical observations
  100. GRB 071031: REM NIR and Optical observation

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