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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"

15714 results found.

  1. GRB051111: XRT preliminary analysis
  2. GRB 051109A Optical Observations
  3. GRB 051111A : Lulin BVRI multi band afterglow observation
  4. GRB 051111A: KAIT optical observations
  5. GRB 051111: ROTSE-III Analysis of Prompt Counterpart
  6. GRB 051109A
  7. GRB 051105a: GETS optical limit
  8. GRB 051109A: KAIT optical observations
  9. Early RAPTOR measurements of GRB 051109a - the movie.
  10. GRB 051109B: ROTSE-III Optical Limits
  11. GRB 051109A: Swift-UVOT Observations
  12. GRB 051109B : Lulin Optical Observations
  13. GRB 051109A : Lulin BVRI Optical afterglow observation
  14. GRB051109A: XRT refined analysis
  15. GRB 051109a: BOOTES R & I-band detection of the early afterglow
  16. GRB 051109B Kiso optical follow-up observation
  17. GRB051105B: REM Optical observation
  18. GRB 051109: HET Optical Spectrum and Absorption Redshift
  19. GRB 051109: Rc and Ic observations
  20. GRB 051109a: IR Photometry and Astrometry
  21. GRB 051109A: ROTSE-III Decline rate for Optical Counterpart
  22. GRB051105B: Swift/XRT upper limit
  23. GRB051103: optical observations
  24. GRB 051103, optical observations
  25. GRB051103: MASTER: OT limit and host galaxy candidates
  26. GRB051028: Swift-XRT refined analysis
  27. GRB 051105a, observation from Naini Tal and OSN
  28. GRB 051105A, 2nd epoch optical observations
  29. GRB 051105A: TNG optical observations
  30. GRB051105A: Swift/UVOT Observations
  31. GRB 051105A, optical observations
  32. GRB 051105b: ART optical limits
  33. GRB 051105B (INTEGRAL 2701): Optical observation
  34. GRB 051105: Optical limit
  35. GRB 051016B host spectroscopy and redshift
  36. GRB051016B: optical observation
  37. Recent GRB UBVRcIc field photometry
  38. GRB 051022: RTT150 optical observations
  39. GRB 051021A: RTT150 optical observations
  40. GRB051028: optical observations
  41. GRB051028: confirmation of the afterglow
  42. GRB051028: WHT optical candidate
  43. GRB 051028 (=H3951): A GRB localized by HETE
  44. GRB051028:MASTER optical observations
  45. GRB 051022: XRT Refined Spectral and Temporal Analysis--Correction
  46. SGR 1806-20: continued moderate activity seen with INTEGRAL
  47. GRB 051021, Optical Observations
  48. GRB 051022: XRT Refined Spectral and Temporal Analysis
  49. GRB 051022, refined optical astrometry
  50. GRB051021B: Swift XRT refined analysis
  51. GRB051021a: optical observations
  52. GRB051021A: Swift XRT refined analysis
  53. GRB051022: Optical Observations
  54. GRB 051022: Spectral Analysis Indicates That The Spectrum Is Absorbed
  55. GRB 051021, SMARTS optical/IR observations
  56. GRB 051022 (=H3950): SXC Flight Localization is Valid
  57. GRB051021: Swift/UVOT Upper Limits
  58. GRB 051022: SSO40 Optical Observations
  59. GRB051022,optical observation
  60. GRB 051022A: ROTSE-III Optical Limits
  61. GRB051022 (=H3590), A GRB Detected By HETE
  62. GRB 051022: Optical observations
  63. GRB 051021,optical observation
  64. GRB051021: Swift XRT analysis
  65. GRB051021 (=H3947): Refined Analysis
  66. GRB 051021 : optical afterglow observation at Lulin
  67. GRB 051021: Optical observations
  68. GRB 051021: ROTSE-III Confirmation of Optical Counterpart
  69. GRB 051021: Optical observations and candidate afterglow
  70. GRB051021.6: MASTER optical observation
  71. GRB051021: A GRB Localized by HETE
  72. GRB 050502b: Optical limit
  73. GRB 051016b: Optical limit
  74. GRB 051016b: Gemini Near IR Observations
  75. GRB 051016B: Swift/UVOT detection
  76. GRB 051016B,optical observation
  77. GRB 051016B : Optical follow-up at Lulin
  78. GRB 051016: LCO optical and near-IR imaging
  79. GRB051006: optical observations
  80. GRB050805A: Rc optical observations
  81. GRB051008: optical candidate
  82. GRB051011: MASTER optical observation
  83. GRB051008: optical observation
  84. GRB 051008, optical observations
  85. GRB 051006: XRT refined analysis
  86. GRB 051006: optical observations at Sierra Nevada
  87. GRB051001: Swift UVOT Upper Limits
  88. GRB 051001, optical observations at Mt. John
  89. GRB 051001: ROTSE-III Optical Limits
  90. GRB050908: optical observations
  91. GRB050922C: optical observation
  92. GRB050922B: optical limit
  93. GRB 050922C: further VLT observations
  94. GRB050922C: UVES/VLT high resolution spectroscopy
  95. GRB050922C - Swift UVOT preliminary analysis
  96. GRB 050922C: break in the lightcurve
  97. GRB050925: Swift UVOT upper limits
  98. GRB050922C: TNG spectroscopic observations
  99. GRB050922B: Swift UVOT early upper limits.
  100. GRB OT observation

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