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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"

36144 results found.

  1. GRB 050607: Optical decay and spectral slope
  2. GRB 050607: MDM Observations
  3. GRB050607,optical observation
  4. GRB 050607 - XRT refined data analysis
  5. Optical Afterglow of GRB 050607
  6. GRB050607 optical limit by "Pi of the Sky"
  7. GRB050607: Swift Detection of a long GRB
  8. GRB050607: P60 Observations
  9. GRB 050603: prediction of t_break
  10. Limits on a SN in the field of GRB 050509b
  11. GRB 050603: Redshift
  12. GRB 050603 - XRT data analysis of the first day
  13. Konus-Wind observation of GRB 050603
  14. GRB 050603: Analysis of UVOT data
  15. GRB 050603: Swift XRT Position
  16. GRB050603: Radio Detection
  17. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  18. GRB 050603: Afterglow Identification from LCO
  19. GRB 050603: INTEGRAL shows it is not a short GRB
  20. GRB 050408: jet break in the XRT light curve
  21. GRB 050525a, infrared observations
  22. GRB 050525a, SMARTS optical/IR afterglow observations
  23. Correction to GCN Circ 3502 on GRB 050528
  24. GRB050528: updated Liverpool Telescope limits
  25. Swift-BAT GRB 050528: a soft burst
  26. Update on Swift-BAT GRB 050528 (Trigger 130679)
  27. GRB050528: BOOTES optical candidate (retraction)
  28. GRB050504: Ashra-P2/3 monitor and Ashra-AFT response
  29. GRB050528: BOOTES optical candidate
  30. Possible GRB050528: no candidate from Liverpool Telescope
  31. Swift-BAT detection of possible GRB 050528
  32. GRB050525a: Radio Observations
  33. GRB 050509b: refined XRT/Chandra afterglow position analysis
  34. GRB 050525: RTT150, Optical observations
  35. GRB050525a: optical upper limits
  36. GRB 050525a: SARA Observations
  37. GRB 050525B: Swift-BAT observations
  38. GRB 050525: MITSuME Optical Observation in VRI
  39. GRB 050525a: MDM Observations
  40. GRB050525A,optical observation
  41. GRB 050525 : Lulin optical afterglow observations
  42. GRB050525: Super-LOTIS observations
  43. GRB 050525, spectral lag pseudo-redshift
  44. GRB 050525a: Gemini/GMOS Spectra
  45. GRB050306: optical afterglow not confirmed
  46. GRB 050525: BART optical observation
  47. GRB 050525A: BOOTES simultaneous optical observations
  48. GRB 050525A: Swift-BAT refined analysis
  49. GRB050525: Optical observations
  50. GRB 050525B: INTEGRAL shows it is unrelated to GRB050525A
  51. GRB 050525: pseudo-redshift
  52. Swift/UVOT UV and optical detections of GRB 050525
  53. Konus-Wind observation of GRB 050525
  54. GRB 050525: TAROT observations of the early afterglow
  55. INTEGRAL detection of GRB 050525
  56. GRB 050525, infrared observations
  57. GRB 050525: Optical observation
  58. GRB 050525: observatons of the optical afterglow
  59. GRB050525: ROTSE-III Refined Analysis
  60. GRB 050525 - Very Bright, Not Short
  61. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  62. GRB 050525A: ROTSE-III Detection of Possible Counterpart
  63. XRF050522: NIR observations of XRT candidate
  64. XRF050522: Radio Observations
  65. GRB 050509A: Further I-band imaging
  66. GRB050522,optical observation
  67. GRB050520,optical observation
  68. XRF 050522: Continued NIR P200 Monitoring
  69. RBO Observations of GRB050522
  70. GRB050509b: optical observations
  71. Recent GRB BVRcIc field photometry
  72. GRB050520: Radio Observations
  73. XRF050522, BVRcIc field photometry
  74. XRF050522: Optical Observations
  75. XRF 050522: KAIT observations
  76. XRF 050522 detected with INTEGRAL
  77. GRB 050520: VLT/ULTRACAM observations
  78. Swift UVOT Observations of GRB 050520
  79. GRB 050520: Swift XRT refined analysis
  80. RBO Observations of GRB050520
  81. GRB 050520: P200 Observations
  82. GRB050520: Liverpool Telescope follow-up
  83. GRB 050520: TAROT optical limit
  84. GRB 050520: Swift XRT position
  85. GRB 050520: VLT/ULTRACAM observations
  86. GRB 050520: OSN optical observations
  87. GRB 050520: BART optical limit
  88. GRB 050520 - A long GRB detected with INTEGRAL
  89. Swift-BAT trigger 122203 is not a real GRB
  90. GRB 050504: Swift XRT afterglow candidate has faded
  91. XRF 050509c optical afterglow
  92. GRB 050509B and short GRB-SN association? (corrected)
  93. GRB 050509B and short GRB-SN association?
  94. GRB 050509B: Subaru Optical Observations
  95. GRB050502b: Early Observation
  96. GRB050509b, Bok telescope B-band imaging
  97. Refined Chandra analysis of GRB 050509b
  98. GRB050509b, SDSS pre-burst observations
  99. GRB 050509b: Keck/Chandra Cross-Correlation
  100. GRB 050509b: Keck/Chandra Cross-Correlation

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