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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"

36194 results found.

  1. GRB 050713A : Lulin R-band observation
  2. GRB 050713A XMM-Newton observation
  3. GRB 050713b : Lulin R-band observations
  4. GRB050713B: Faulkes North Telescope observation
  5. RBO RI observations of GRB 050713A
  6. GRB 050713B
  7. GRB050709 : Chandra source optical counterpart
  8. GRB050713: Liverpool Telescope prompt observations
  9. GRB 050712, optical observations
  10. GRB 050713 : Planned XMM-Newton observation
  11. GRB050709: Candidate X-ray Afterglow from Chandra
  12. GRB 050713, R-band observations at NOT
  13. GRB 050713: ARC NIR Detections and Identification of Fading
  14. GRB050713: possible I-band afterglow
  15. GRB 050713: Swift detection of Bright Burst
  16. GRB 050713A: ROTSE-III Optical Limits
  17. GRB 050709: Swift UVOT and XRT observations
  18. GRB 050712: Swift-BAT Refined Analysis
  19. GRB 050712: Swift XRT afterglow position
  20. GRB 050712: Swift detection of a weak burst
  21. GRB 050709: LCO40 Observations
  22. GRB050709: A Possible Short-Hard GRB Localized by HETE
  23. PROMPT Rc Observations of GRB 050709
  24. GRB 050525a: PROMPT VRcIc Detections
  25. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  26. GRB 050525a: ARC 3.5-Meter SPIcam Field Calibration
  27. GRB 050626 optical observations
  28. GRB 050626: Swift XRT observations
  29. GRB 050701
  30. GRB 050701, optical observations
  31. GRB 050408: ARC 3.5-meter NIR Observations
  32. GRB 050701: Refined XRT analysis
  33. Swift UVOT observations of GRB 050701
  34. GRB 050701: Swift XRT afterglow position
  35. Swift trigger 143708 is really GRB 050701
  36. GRB 050607, radio observations
  37. GRB 050626 - Correction to GCN 3552
  38. GRB 050626 - a long GRB detected with INTEGRAL
  39. GRB 050525A: Swift Late-Time Decay Rate
  40. H3804: A Possible New XRB Detected by HETE
  41. XRF 050509c: Optical monitoring
  42. IBAS Alert #2512 is NOT a GRB
  43. GRB 050416(a): Host Galaxy Redshift Determination
  44. GRB 050607: MDM Observation
  45. GRB 050607 optical decay
  46. GRB 050607: RTT150 optical observations
  47. GRB 050607 : Lulin R-band observation
  48. GRB 050607: PROMPT VRcIc Observations
  49. GRB 050607: RAPTOR-S Early Optical Limits
  50. GRB 050525a, Mid-Infrared Observations
  51. GRB 050607: Optical decay and spectral slope
  52. GRB 050607: MDM Observations
  53. GRB050607,optical observation
  54. GRB 050607 - XRT refined data analysis
  55. Optical Afterglow of GRB 050607
  56. GRB050607 optical limit by "Pi of the Sky"
  57. GRB050607: Swift Detection of a long GRB
  58. GRB050607: P60 Observations
  59. GRB 050603: prediction of t_break
  60. Limits on a SN in the field of GRB 050509b
  61. GRB 050603: Redshift
  62. GRB 050603 - XRT data analysis of the first day
  63. Konus-Wind observation of GRB 050603
  64. GRB 050603: Analysis of UVOT data
  65. GRB 050603: Swift XRT Position
  66. GRB050603: Radio Detection
  67. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  68. GRB 050603: Afterglow Identification from LCO
  69. GRB 050603: INTEGRAL shows it is not a short GRB
  70. GRB 050408: jet break in the XRT light curve
  71. GRB 050525a, infrared observations
  72. GRB 050525a, SMARTS optical/IR afterglow observations
  73. Correction to GCN Circ 3502 on GRB 050528
  74. GRB050528: updated Liverpool Telescope limits
  75. Swift-BAT GRB 050528: a soft burst
  76. Update on Swift-BAT GRB 050528 (Trigger 130679)
  77. GRB050528: BOOTES optical candidate (retraction)
  78. GRB050504: Ashra-P2/3 monitor and Ashra-AFT response
  79. GRB050528: BOOTES optical candidate
  80. Possible GRB050528: no candidate from Liverpool Telescope
  81. Swift-BAT detection of possible GRB 050528
  82. GRB050525a: Radio Observations
  83. GRB 050509b: refined XRT/Chandra afterglow position analysis
  84. GRB 050525: RTT150, Optical observations
  85. GRB050525a: optical upper limits
  86. GRB 050525a: SARA Observations
  87. GRB 050525B: Swift-BAT observations
  88. GRB 050525: MITSuME Optical Observation in VRI
  89. GRB 050525a: MDM Observations
  90. GRB050525A,optical observation
  91. GRB 050525 : Lulin optical afterglow observations
  92. GRB050525: Super-LOTIS observations
  93. GRB 050525, spectral lag pseudo-redshift
  94. GRB 050525a: Gemini/GMOS Spectra
  95. GRB050306: optical afterglow not confirmed
  96. GRB 050525: BART optical observation
  97. GRB 050525A: BOOTES simultaneous optical observations
  98. GRB 050525A: Swift-BAT refined analysis
  99. GRB050525: Optical observations
  100. GRB 050525B: INTEGRAL shows it is unrelated to GRB050525A

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