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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"

24672 results found.

  1. GRB 050607 optical decay
  2. GRB050607: refined analysis of prompt REM observations
  3. GRB 050607: PROMPT VRcIc Observations
  4. GRB 050607: Optical decay and spectral slope
  5. GRB050607,optical observation
  6. Optical Afterglow of GRB 050607
  7. GRB050607: Swift Detection of a long GRB
  8. GRB050607: prompt REM observations
  9. Limits on a SN in the field of GRB 050509b
  10. GRB 050603 - XRT data analysis of the first day
  11. GRB050603, submillimetre observations
  12. GRB050603: Radio Detection
  13. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  14. GRB 050603: INTEGRAL shows it is not a short GRB
  15. GRB 050525a, infrared observations
  16. GRB050528, XRT observations
  17. GRB050528: updated Liverpool Telescope limits
  18. Swift-BAT GRB 050528: a soft burst
  19. GRB050504: Ashra-P2/3 monitor and Ashra-AFT response
  20. Possible GRB050528: no candidate from Liverpool Telescope
  21. GRB050525a: Radio Observations
  22. GRB 050509b: refined XRT/Chandra afterglow position analysis
  23. GRB 050525: RTT150, Optical observations
  24. GRB 050525a: SARA Observations
  25. GRB 050525B: Swift-BAT observations
  26. GRB 050525: MITSuME Optical Observation in VRI
  27. GRB050525A,optical observation
  28. GRB050525: Super-LOTIS observations
  29. GRB 050525, spectral lag pseudo-redshift
  30. GRB050306: optical afterglow not confirmed
  31. GRB 050525: BART optical observation
  32. GRB 050525A: BOOTES simultaneous optical observations
  33. GRB 050525A: Swift-BAT refined analysis
  34. GRB050525: Optical observations
  35. GRB 050525B: INTEGRAL shows it is unrelated to GRB050525A
  36. Konus-Wind observation of GRB 050525
  37. GRB 050525: TAROT observations of the early afterglow
  38. INTEGRAL detection of GRB 050525
  39. GRB 050525, infrared observations
  40. GRB 050525: observatons of the optical afterglow
  41. GRB050525: ROTSE-III Refined Analysis
  42. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  43. XRF050522: Radio Observations
  44. Swift/UVOT observation of XRF 050522
  45. GRB 050509A: Further I-band imaging
  46. GRB050522,optical observation
  47. GRB050520,optical observation
  48. XRF 050522: Continued NIR P200 Monitoring
  49. RBO Observations of GRB050522
  50. Recent GRB BVRcIc field photometry
  51. GRB050520: Radio Observations
  52. XRF 050522: Swift XRT observation
  53. XRF050522, BVRcIc field photometry
  54. XRF050522: Optical Observations
  55. XRF050522: Near-infrared Observations
  56. GRB 050520: VLT/ULTRACAM observations
  57. GRB 050520: Swift XRT refined analysis
  58. XRF050509C: Chandra Afterglow Detection
  59. XRF050509c: Radio Observations
  60. GRB 050520: P200 Observations
  61. GRB 050520: TAROT optical limit
  62. GRB 050520: VLT/ULTRACAM observations
  63. XRF 050509c optical afterglow
  64. GRB 050509B and short GRB-SN association? (corrected)
  65. GRB 050509B and short GRB-SN association?
  66. GRB050502b: Early Observation
  67. GRB050509b, Bok telescope B-band imaging
  68. Refined Chandra analysis of GRB 050509b
  69. GRB050509b, SDSS pre-burst observations
  70. GRB 050509b: Keck/Chandra Cross-Correlation
  71. GRB 050509b: Keck/Chandra Cross-Correlation
  72. Chandra observation of GRB 050509b
  73. GRB 050509b: RAPTOR deep, early limits.
  74. GRB050509B: Optical observations at the Very Large Telescope
  75. GRB 050509b: No Optical Variability in XRT Error Circle
  76. GRB 050509a: Swift-BAT refined analysis
  77. GRB 050509c: ROTSE-III Optical Limits
  78. GRB 050505, early TAROT observation
  79. GRB050509c: REM NIR and Optical observations
  80. GRB 050509b: Physical Properties of the Candidate Host galaxy
  81. GRB 050505: SARA Observations
  82. GRB 050509B, Optical Observations
  83. GRB 050509B: Swift/XRT refined analysis
  84. GRB 050509b: Optical observations
  85. GRB 050509A: Optical observations
  86. GRB050509b: Radio Observations
  87. GRB 050509b: PAIRITEL and WIYN Observations
  88. GRB 050509b: Swift-BAT refined analysis of the short hard burst
  89. Swift Detection of GRB050509b: A short duration burst
  90. Swift Detection of the Burst GRB050509
  91. GRB 050505: early time observations
  92. GRB 050505, simultaneous optical observation
  93. GRB050505: AAVSO observations
  94. GRB050416A : 1 GHz limit from GMRT
  95. GRB050505: Optical Afterglow Candidate
  96. GRB050505 Swift-BAT refined analysis
  97. GRB 050416b:Swift XRT afterglow upper limits
  98. GRB 050416b:Swift XRT afterglow upper limits
  99. GRB050502b: Afterglow Confirmation: Correction to OT Coordinates
  100. GRB050502b: Afterglow Confirmation

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