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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"

36188 results found.

  1. GRB050709 : Chandra source optical counterpart
  2. GRB050713: Liverpool Telescope prompt observations
  3. GRB 050712, optical observations
  4. GRB 050713 : Planned XMM-Newton observation
  5. GRB050709: Candidate X-ray Afterglow from Chandra
  6. GRB 050713, R-band observations at NOT
  7. GRB 050713: ARC NIR Detections and Identification of Fading
  8. GRB050713: possible I-band afterglow
  9. GRB 050713: Swift detection of Bright Burst
  10. GRB 050713A: ROTSE-III Optical Limits
  11. GRB 050709: Swift UVOT and XRT observations
  12. GRB 050712: Swift-BAT Refined Analysis
  13. GRB 050712: Swift XRT afterglow position
  14. GRB 050712: Swift detection of a weak burst
  15. GRB 050709: LCO40 Observations
  16. GRB050709: A Possible Short-Hard GRB Localized by HETE
  17. PROMPT Rc Observations of GRB 050709
  18. GRB 050525a: PROMPT VRcIc Detections
  19. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  20. GRB 050525a: ARC 3.5-Meter SPIcam Field Calibration
  21. GRB 050626 optical observations
  22. GRB 050626: Swift XRT observations
  23. GRB 050701
  24. GRB 050701, optical observations
  25. GRB 050408: ARC 3.5-meter NIR Observations
  26. GRB 050701: Refined XRT analysis
  27. Swift UVOT observations of GRB 050701
  28. GRB 050701: Swift XRT afterglow position
  29. Swift trigger 143708 is really GRB 050701
  30. GRB 050607, radio observations
  31. GRB 050626 - Correction to GCN 3552
  32. GRB 050626 - a long GRB detected with INTEGRAL
  33. GRB 050525A: Swift Late-Time Decay Rate
  34. H3804: A Possible New XRB Detected by HETE
  35. XRF 050509c: Optical monitoring
  36. IBAS Alert #2512 is NOT a GRB
  37. GRB 050416(a): Host Galaxy Redshift Determination
  38. GRB 050607: MDM Observation
  39. GRB 050607 optical decay
  40. GRB 050607: RTT150 optical observations
  41. GRB 050607 : Lulin R-band observation
  42. GRB 050607: PROMPT VRcIc Observations
  43. GRB 050607: RAPTOR-S Early Optical Limits
  44. GRB 050525a, Mid-Infrared Observations
  45. GRB 050607: Optical decay and spectral slope
  46. GRB 050607: MDM Observations
  47. GRB050607,optical observation
  48. GRB 050607 - XRT refined data analysis
  49. Optical Afterglow of GRB 050607
  50. GRB050607 optical limit by "Pi of the Sky"
  51. GRB050607: Swift Detection of a long GRB
  52. GRB050607: P60 Observations
  53. GRB 050603: prediction of t_break
  54. Limits on a SN in the field of GRB 050509b
  55. GRB 050603: Redshift
  56. GRB 050603 - XRT data analysis of the first day
  57. Konus-Wind observation of GRB 050603
  58. GRB 050603: Analysis of UVOT data
  59. GRB 050603: Swift XRT Position
  60. GRB050603: Radio Detection
  61. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  62. GRB 050603: Afterglow Identification from LCO
  63. GRB 050603: INTEGRAL shows it is not a short GRB
  64. GRB 050408: jet break in the XRT light curve
  65. GRB 050525a, infrared observations
  66. GRB 050525a, SMARTS optical/IR afterglow observations
  67. Correction to GCN Circ 3502 on GRB 050528
  68. GRB050528: updated Liverpool Telescope limits
  69. Swift-BAT GRB 050528: a soft burst
  70. Update on Swift-BAT GRB 050528 (Trigger 130679)
  71. GRB050528: BOOTES optical candidate (retraction)
  72. GRB050504: Ashra-P2/3 monitor and Ashra-AFT response
  73. GRB050528: BOOTES optical candidate
  74. Possible GRB050528: no candidate from Liverpool Telescope
  75. Swift-BAT detection of possible GRB 050528
  76. GRB050525a: Radio Observations
  77. GRB 050509b: refined XRT/Chandra afterglow position analysis
  78. GRB 050525: RTT150, Optical observations
  79. GRB050525a: optical upper limits
  80. GRB 050525a: SARA Observations
  81. GRB 050525B: Swift-BAT observations
  82. GRB 050525: MITSuME Optical Observation in VRI
  83. GRB 050525a: MDM Observations
  84. GRB050525A,optical observation
  85. GRB 050525 : Lulin optical afterglow observations
  86. GRB050525: Super-LOTIS observations
  87. GRB 050525, spectral lag pseudo-redshift
  88. GRB 050525a: Gemini/GMOS Spectra
  89. GRB050306: optical afterglow not confirmed
  90. GRB 050525: BART optical observation
  91. GRB 050525A: BOOTES simultaneous optical observations
  92. GRB 050525A: Swift-BAT refined analysis
  93. GRB050525: Optical observations
  94. GRB 050525B: INTEGRAL shows it is unrelated to GRB050525A
  95. GRB 050525: pseudo-redshift
  96. Swift/UVOT UV and optical detections of GRB 050525
  97. Konus-Wind observation of GRB 050525
  98. GRB 050525: TAROT observations of the early afterglow
  99. INTEGRAL detection of GRB 050525
  100. GRB 050525, infrared observations

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