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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"

15251 results found.

  1. GRB 050709: Spectroscopy
  2. GRB 050713A : Swift-BAT Refined Analysis
  3. GRB050713: Liverpool Telescope prompt observations
  4. GRB 050712, optical observations
  5. GRB 050713, R-band observations at NOT
  6. GRB050709, optical observations
  7. GRB050709: A Possible Short-Hard GRB Localized by HETE
  8. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  9. CORRECTION: GRB050603 Swift UVOT Afterglow Observations
  10. H3800 and H3801 on 2005 June 11: two bursts from SGR1806-20 localized by HETE
  11. GRB 050416(a): Host Galaxy Redshift Determination
  12. GRB050607: refined analysis of prompt REM observations
  13. GRB 050607: RAPTOR-S Early Optical Limits
  14. GRB050607: KAIT optical limits
  15. GRB 050525a, Mid-Infrared Observations
  16. GRB 050607: Optical decay and spectral slope
  17. GRB050607,optical observation
  18. GRB 050607 - XRT refined data analysis
  19. GRB 050603: prediction of t_break
  20. GRB 050603: Redshift
  21. Konus-Wind observation of GRB 050603
  22. GRB 050603: Analysis of UVOT data
  23. GRB050603: Fading Afterglow observed by Swift UVOT
  24. GRB050603, submillimetre observations
  25. GRB 050603: Swift XRT Position
  26. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  27. GRB 050603: INTEGRAL shows it is not a short GRB
  28. GRB 050408: jet break in the XRT light curve
  29. GRB 050525a, SMARTS optical/IR afterglow observations
  30. GRB050528: BOOTES optical candidate (retraction)
  31. Possible GRB050528: no candidate from Liverpool Telescope
  32. GRB 050509b: refined XRT/Chandra afterglow position analysis
  33. GRB 050525B: Swift-BAT observations
  34. GRB050525A,optical observation
  35. GRB 050525 : Lulin optical afterglow observations
  36. GRB050525: Super-LOTIS observations
  37. GRB 050525, spectral lag pseudo-redshift
  38. GRB 050525: BART optical observation
  39. GRB 050525A: Swift-BAT refined analysis
  40. GRB050525: Optical observations
  41. GRB 050525B: INTEGRAL shows it is unrelated to GRB050525A
  42. Konus-Wind observation of GRB 050525
  43. GRB 050525: TAROT observations of the early afterglow
  44. GRB 050525, infrared observations
  45. GRB 050525: observatons of the optical afterglow
  46. GRB050525: ROTSE-III Refined Analysis
  47. XRF050522: NIR observations of XRT candidate
  48. XRF 050522: Swift XRT refined analysis
  49. XRF 050522: Swift XRT observation
  50. XRF050522, BVRcIc field photometry
  51. XRF050522: Optical Observations
  52. XRF 050522 detected with INTEGRAL
  53. GRB 050520: VLT/ULTRACAM observations
  54. GRB 050520: Swift XRT refined analysis
  55. GRB 050520: Swift XRT position
  56. GRB 050520: VLT/ULTRACAM observations
  57. GRB 050520 - A long GRB detected with INTEGRAL
  58. GRB 050504: Swift XRT afterglow candidate has faded
  59. GRB 050509B and short GRB-SN association? (corrected)
  60. GRB 050509B and short GRB-SN association?
  61. Refined Chandra analysis of GRB 050509b
  62. GRB050509b, SDSS pre-burst observations
  63. GRB 050509b: Keck/Chandra Cross-Correlation
  64. GRB 050509b: Keck/Chandra Cross-Correlation
  65. Chandra observation of GRB 050509b
  66. GRB 050509b Milagro GeV/TeV Observations
  67. GRB050509B: Optical observations at the Very Large Telescope
  68. GRB 050509c: ROTSE-III Optical Limits
  69. GRB 050505, early TAROT observation
  70. GRB 050509b: Further Analysis of Keck LRIS Images
  71. GRB 050509b: Precision Astrometry
  72. GRB 050509b: optical observations
  73. GRB 050509b: Swift XRT Position
  74. GRB 050509a: Swift XRT Position
  75. GRB 050505: Keck I-band Magnitude
  76. GRB050505: AAVSO observations
  77. GRB050416A : 1 GHz limit from GMRT
  78. GRB 050505: Keck absorption spectrum and redshift (z=4.27)
  79. GRB050505: Optical Afterglow Candidate
  80. GRB 050505: Swift XRT Position
  81. GRB 050504: Swift XRT position
  82. GRB050502b: Afterglow Confirmation: Correction to OT Coordinates
  83. GRB050502b: Afterglow Confirmation
  84. GRB050502: P200 Observations (Correction)
  85. GRB050502: P200 Observations
  86. GRB 050504: A long GRB detected with INTEGRAL
  87. GRB050502a: P60 Observations (Correction)
  88. GRB050502a: P60 Observations
  89. GRB 050502a: RBO Observations
  90. GRB050502A: Optical Observations
  91. Swift UVOT refined analysis
  92. GRB 050502b: Swift XRT Position
  93. GRB 050502A: Redshift measurement based on Keck HIRES Observations
  94. GRB050502B: Optical Limits from ANU 1m
  95. GRB 050502: INTEGRAL results
  96. GRB 050502: PAIRITEL IR Observations
  97. GRB050416a: Radio Detection
  98. GRB 050422: Swift XRT Position
  99. GRB 050421: SLOTIS observations
  100. GRB 050421: Further Analysis of IR imaging

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