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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"

28100 results found.

  1. GRB050713: Liverpool Telescope prompt observations
  2. GRB 050712, optical observations
  3. GRB050709: Candidate X-ray Afterglow from Chandra
  4. GRB050713: possible I-band afterglow
  5. GRB050712: XRT refined analysis
  6. GRB050709: Radio Observations
  7. GRB 050709: Swift UVOT and XRT observations
  8. GRB 050712: Swift-BAT Refined Analysis
  9. GRB050712: UVOT candidate optical counterpart
  10. GRB 050709: LCO40 Observations
  11. GRB050709, optical observations
  12. PROMPT Rc Observations of GRB 050709
  13. GRB 050525a: PROMPT VRcIc Detections
  14. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  15. GRB 050525a: ARC 3.5-Meter SPIcam Field Calibration
  16. GRB 050626: Swift XRT observations
  17. GRB 050408: ARC 3.5-meter NIR Observations
  18. GRB 050701: Refined XRT analysis
  19. Swift UVOT observations of GRB 050701
  20. GRB050701: Swift-BAT Refined analysis
  21. Swift trigger 143708 is really GRB 050701
  22. GRB 050607, radio observations
  23. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  24. GRB050525a: HST Observations
  25. H3800 and H3801 on 2005 June 11: two bursts from SGR1806-20 localized by HETE
  26. XRF 050509c: Optical monitoring
  27. Konus-Wind observation of an intermediate burst from SGR 1806-20
  28. XRF050509c: Radio Detection
  29. GRB 050607 optical decay
  30. GRB050607: refined analysis of prompt REM observations
  31. GRB 050607: PROMPT VRcIc Observations
  32. GRB 050607: Optical decay and spectral slope
  33. GRB050607,optical observation
  34. Optical Afterglow of GRB 050607
  35. GRB050607: Swift Detection of a long GRB
  36. GRB050607: prompt REM observations
  37. Limits on a SN in the field of GRB 050509b
  38. GRB 050603 - XRT data analysis of the first day
  39. GRB050603, submillimetre observations
  40. GRB050603: Radio Detection
  41. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  42. GRB 050603: INTEGRAL shows it is not a short GRB
  43. GRB 050525a, infrared observations
  44. GRB050528, XRT observations
  45. GRB050528: updated Liverpool Telescope limits
  46. Swift-BAT GRB 050528: a soft burst
  47. GRB050504: Ashra-P2/3 monitor and Ashra-AFT response
  48. Possible GRB050528: no candidate from Liverpool Telescope
  49. GRB050525a: Radio Observations
  50. GRB 050509b: refined XRT/Chandra afterglow position analysis
  51. GRB 050525: RTT150, Optical observations
  52. GRB 050525a: SARA Observations
  53. GRB 050525B: Swift-BAT observations
  54. GRB 050525: MITSuME Optical Observation in VRI
  55. GRB050525A,optical observation
  56. GRB050525: Super-LOTIS observations
  57. GRB 050525, spectral lag pseudo-redshift
  58. GRB050306: optical afterglow not confirmed
  59. GRB 050525: BART optical observation
  60. GRB 050525A: BOOTES simultaneous optical observations
  61. GRB 050525A: Swift-BAT refined analysis
  62. GRB050525: Optical observations
  63. GRB 050525B: INTEGRAL shows it is unrelated to GRB050525A
  64. Konus-Wind observation of GRB 050525
  65. GRB 050525: TAROT observations of the early afterglow
  66. INTEGRAL detection of GRB 050525
  67. GRB 050525, infrared observations
  68. GRB 050525: observatons of the optical afterglow
  69. GRB050525: ROTSE-III Refined Analysis
  70. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  71. XRF050522: Radio Observations
  72. Swift/UVOT observation of XRF 050522
  73. GRB 050509A: Further I-band imaging
  74. GRB050522,optical observation
  75. GRB050520,optical observation
  76. XRF 050522: Continued NIR P200 Monitoring
  77. RBO Observations of GRB050522
  78. Recent GRB BVRcIc field photometry
  79. GRB050520: Radio Observations
  80. XRF 050522: Swift XRT observation
  81. XRF050522, BVRcIc field photometry
  82. XRF050522: Optical Observations
  83. XRF050522: Near-infrared Observations
  84. GRB 050520: VLT/ULTRACAM observations
  85. GRB 050520: Swift XRT refined analysis
  86. XRF050509C: Chandra Afterglow Detection
  87. XRF050509c: Radio Observations
  88. GRB 050520: P200 Observations
  89. GRB 050520: TAROT optical limit
  90. GRB 050520: VLT/ULTRACAM observations
  91. XRF 050509c optical afterglow
  92. GRB 050509B and short GRB-SN association? (corrected)
  93. GRB 050509B and short GRB-SN association?
  94. GRB050502b: Early Observation
  95. GRB050509b, Bok telescope B-band imaging
  96. Refined Chandra analysis of GRB 050509b
  97. GRB050509b, SDSS pre-burst observations
  98. GRB 050509b: Keck/Chandra Cross-Correlation
  99. GRB 050509b: Keck/Chandra Cross-Correlation
  100. Chandra observation of GRB 050509b

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