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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"

36159 results found.

  1. GRB 050607, radio observations
  2. GRB 050626 - Correction to GCN 3552
  3. GRB 050626 - a long GRB detected with INTEGRAL
  4. GRB 050525A: Swift Late-Time Decay Rate
  5. H3804: A Possible New XRB Detected by HETE
  6. XRF 050509c: Optical monitoring
  7. IBAS Alert #2512 is NOT a GRB
  8. GRB 050416(a): Host Galaxy Redshift Determination
  9. GRB 050607: MDM Observation
  10. GRB 050607 optical decay
  11. GRB 050607: RTT150 optical observations
  12. GRB 050607 : Lulin R-band observation
  13. GRB 050607: PROMPT VRcIc Observations
  14. GRB 050607: RAPTOR-S Early Optical Limits
  15. GRB 050525a, Mid-Infrared Observations
  16. GRB 050607: Optical decay and spectral slope
  17. GRB 050607: MDM Observations
  18. GRB050607,optical observation
  19. GRB 050607 - XRT refined data analysis
  20. Optical Afterglow of GRB 050607
  21. GRB050607 optical limit by "Pi of the Sky"
  22. GRB050607: Swift Detection of a long GRB
  23. GRB050607: P60 Observations
  24. GRB 050603: prediction of t_break
  25. Limits on a SN in the field of GRB 050509b
  26. GRB 050603: Redshift
  27. GRB 050603 - XRT data analysis of the first day
  28. Konus-Wind observation of GRB 050603
  29. GRB 050603: Analysis of UVOT data
  30. GRB 050603: Swift XRT Position
  31. GRB050603: Radio Detection
  32. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  33. GRB 050603: Afterglow Identification from LCO
  34. GRB 050603: INTEGRAL shows it is not a short GRB
  35. GRB 050408: jet break in the XRT light curve
  36. GRB 050525a, infrared observations
  37. GRB 050525a, SMARTS optical/IR afterglow observations
  38. Correction to GCN Circ 3502 on GRB 050528
  39. GRB050528: updated Liverpool Telescope limits
  40. Swift-BAT GRB 050528: a soft burst
  41. Update on Swift-BAT GRB 050528 (Trigger 130679)
  42. GRB050528: BOOTES optical candidate (retraction)
  43. GRB050504: Ashra-P2/3 monitor and Ashra-AFT response
  44. GRB050528: BOOTES optical candidate
  45. Possible GRB050528: no candidate from Liverpool Telescope
  46. Swift-BAT detection of possible GRB 050528
  47. GRB050525a: Radio Observations
  48. GRB 050509b: refined XRT/Chandra afterglow position analysis
  49. GRB 050525: RTT150, Optical observations
  50. GRB050525a: optical upper limits
  51. GRB 050525a: SARA Observations
  52. GRB 050525B: Swift-BAT observations
  53. GRB 050525: MITSuME Optical Observation in VRI
  54. GRB 050525a: MDM Observations
  55. GRB050525A,optical observation
  56. GRB 050525 : Lulin optical afterglow observations
  57. GRB050525: Super-LOTIS observations
  58. GRB 050525, spectral lag pseudo-redshift
  59. GRB 050525a: Gemini/GMOS Spectra
  60. GRB050306: optical afterglow not confirmed
  61. GRB 050525: BART optical observation
  62. GRB 050525A: BOOTES simultaneous optical observations
  63. GRB 050525A: Swift-BAT refined analysis
  64. GRB050525: Optical observations
  65. GRB 050525B: INTEGRAL shows it is unrelated to GRB050525A
  66. GRB 050525: pseudo-redshift
  67. Swift/UVOT UV and optical detections of GRB 050525
  68. Konus-Wind observation of GRB 050525
  69. GRB 050525: TAROT observations of the early afterglow
  70. INTEGRAL detection of GRB 050525
  71. GRB 050525, infrared observations
  72. GRB 050525: Optical observation
  73. GRB 050525: observatons of the optical afterglow
  74. GRB050525: ROTSE-III Refined Analysis
  75. GRB 050525 - Very Bright, Not Short
  76. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  77. GRB 050525A: ROTSE-III Detection of Possible Counterpart
  78. XRF050522: NIR observations of XRT candidate
  79. XRF050522: Radio Observations
  80. GRB 050509A: Further I-band imaging
  81. GRB050522,optical observation
  82. GRB050520,optical observation
  83. XRF 050522: Continued NIR P200 Monitoring
  84. RBO Observations of GRB050522
  85. GRB050509b: optical observations
  86. Recent GRB BVRcIc field photometry
  87. GRB050520: Radio Observations
  88. XRF050522, BVRcIc field photometry
  89. XRF050522: Optical Observations
  90. XRF 050522: KAIT observations
  91. XRF 050522 detected with INTEGRAL
  92. GRB 050520: VLT/ULTRACAM observations
  93. Swift UVOT Observations of GRB 050520
  94. GRB 050520: Swift XRT refined analysis
  95. RBO Observations of GRB050520
  96. GRB 050520: P200 Observations
  97. GRB050520: Liverpool Telescope follow-up
  98. GRB 050520: TAROT optical limit
  99. GRB 050520: Swift XRT position
  100. GRB 050520: VLT/ULTRACAM observations

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