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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"

32494 results found.

  1. GRB 050525: observatons of the optical afterglow
  2. GRB050525: ROTSE-III Refined Analysis
  3. GRB 050525 - Very Bright, Not Short
  4. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  5. GRB 050525A: ROTSE-III Detection of Possible Counterpart
  6. XRF050522: NIR observations of XRT candidate
  7. XRF 050522: Swift XRT refined analysis
  8. XRF050522: Radio Observations
  9. Swift/UVOT observation of XRF 050522
  10. GRB 050509A: Further I-band imaging
  11. XRF 050522: Continued NIR P200 Monitoring
  12. RBO Observations of GRB050522
  13. GRB050520: Radio Observations
  14. XRF 050522: Swift XRT observation
  15. XRF050522, BVRcIc field photometry
  16. XRF 050522 : Lulin observations
  17. XRF050522: Optical Observations
  18. XRF050522: Near-infrared Observations
  19. XRF 050522: KAIT observations
  20. GRB 050520: VLT/ULTRACAM observations
  21. Swift UVOT Observations of GRB 050520
  22. GRB 050520: Swift XRT refined analysis
  23. XRF050509C: Chandra Afterglow Detection
  24. XRF 050509c: Swift XRT Upper Limit
  25. XRF050509c: Radio Observations
  26. RBO Observations of GRB050520
  27. GRB 050520: P200 Observations
  28. GRB050520: Liverpool Telescope follow-up
  29. GRB 050520: TAROT optical limit
  30. GRB 050520: Swift XRT position
  31. GRB 050520: VLT/ULTRACAM observations
  32. GRB 050520: OSN optical observations
  33. No Swift-BAT Lightcurves in real-time for next 3 weeks
  34. Swift-BAT trigger 122203 is not a real GRB
  35. XRF 050509C: REM NIR and Optical refined analysis
  36. GRB 050504: Swift XRT afterglow candidate has faded
  37. XRF 050509c optical afterglow
  38. GRB 050509B and short GRB-SN association? (corrected)
  39. GRB 050509B and short GRB-SN association?
  40. GRB 050509B: Subaru Optical Observations
  41. GRB050502b: Early Observation
  42. GRB050509b, Bok telescope B-band imaging
  43. Refined Chandra analysis of GRB 050509b
  44. GRB050509b, SDSS pre-burst observations
  45. GRB 050509b: Keck/Chandra Cross-Correlation
  46. Chandra observation of GRB 050509b
  47. GRB 050509b: RAPTOR deep, early limits.
  48. GRB050509B: Optical/Infared observations
  49. GRB 050509b: Swift/UVOT follow-up measurements
  50. GRB 050509b Milagro GeV/TeV Observations
  51. GRB050509B: Optical observations at the Very Large Telescope
  52. GRB 050509b: No Optical Variability in XRT Error Circle
  53. GRB050416: Afterglow detection at 188 nm with Swift UVOT
  54. GRB 050509a: Swift-BAT refined analysis
  55. GRB 050509c: ROTSE-III Optical Limits
  56. GRB 050509B: WSRT Radio Observations
  57. GRB050509c: REM NIR and Optical observations (errata corrige to GCN 3400)
  58. GRB 050505, early TAROT observation
  59. GRB050509c (=H3751): An X-Ray Flash Localized By HETE
  60. GRB 050509b: Further Analysis of Keck LRIS Images
  61. GRB 050509b: Physical Properties of the Candidate Host galaxy
  62. GRB 050505: SARA Observations
  63. Swift UVOT Follow-up Observations of GRB 050509B
  64. GRB 050509B, Optical Observations
  65. GRB 050509B: Swift/XRT refined analysis
  66. GRB050509a: Swift UVOT observations
  67. GRB 050509b: Optical observations
  68. GRB 050509b: Precision Astrometry
  69. GRB 050509b: Possible Optical Counterpart
  70. GRB 050509A: Optical observations
  71. GRB 050509b: Optical Counterpart Candidate
  72. GRB050509b: Radio Observations
  73. GRB 050509b: Swift-BAT refined analysis of the short hard burst
  74. GRB 050509b: optical observations
  75. GRB 050509b: Swift XRT Position
  76. GRB 050509B: ROTSE-III Optical Limits
  77. GRB 050509a: Swift XRT Position
  78. GRB 050505: Keck I-band Magnitude
  79. GRB 050505: early time observations
  80. GRB 050502a: Swift XRT Upper Limit
  81. GRB 050505, simultaneous optical observation
  82. GRB050505: Infrared observations
  83. GRB 050505: Further Swift UVOT observations.
  84. GRB050505: AAVSO observations
  85. GRB050416A : 1 GHz limit from GMRT
  86. GRB 050505: Keck absorption spectrum and redshift (z=4.27)
  87. GRB 050505 UVOT
  88. GRB050505: Optical Afterglow Candidate
  89. GRB 050505: Swift XRT Position
  90. GRB050505 Swift-BAT refined analysis
  91. GRB 050502a: Optical Observations
  92. GRB 050416b:Swift XRT afterglow upper limits
  93. GRB 050416b:Swift XRT afterglow upper limits
  94. Swift-BAT detection of GRB050505
  95. GRB 050504: Swift XRT position
  96. GRB050502b: Afterglow Confirmation: Correction to OT Coordinates
  97. GRB050502b: Afterglow Confirmation
  98. GRB050502: P200 Observations (Correction)
  99. GRB050502: P200 Observations
  100. GRB 050504 : R band observation at Lulin observatory

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