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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"

28090 results found.

  1. GRB050709, optical observations
  2. PROMPT Rc Observations of GRB 050709
  3. GRB 050525a: PROMPT VRcIc Detections
  4. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  5. GRB 050525a: ARC 3.5-Meter SPIcam Field Calibration
  6. GRB 050626: Swift XRT observations
  7. GRB 050408: ARC 3.5-meter NIR Observations
  8. GRB 050701: Refined XRT analysis
  9. Swift UVOT observations of GRB 050701
  10. GRB050701: Swift-BAT Refined analysis
  11. Swift trigger 143708 is really GRB 050701
  12. GRB 050607, radio observations
  13. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  14. GRB050525a: HST Observations
  15. H3800 and H3801 on 2005 June 11: two bursts from SGR1806-20 localized by HETE
  16. XRF 050509c: Optical monitoring
  17. Konus-Wind observation of an intermediate burst from SGR 1806-20
  18. XRF050509c: Radio Detection
  19. GRB 050607 optical decay
  20. GRB050607: refined analysis of prompt REM observations
  21. GRB 050607: PROMPT VRcIc Observations
  22. GRB 050607: Optical decay and spectral slope
  23. GRB050607,optical observation
  24. Optical Afterglow of GRB 050607
  25. GRB050607: Swift Detection of a long GRB
  26. GRB050607: prompt REM observations
  27. Limits on a SN in the field of GRB 050509b
  28. GRB 050603 - XRT data analysis of the first day
  29. GRB050603, submillimetre observations
  30. GRB050603: Radio Detection
  31. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  32. GRB 050603: INTEGRAL shows it is not a short GRB
  33. GRB 050525a, infrared observations
  34. GRB050528, XRT observations
  35. GRB050528: updated Liverpool Telescope limits
  36. Swift-BAT GRB 050528: a soft burst
  37. GRB050504: Ashra-P2/3 monitor and Ashra-AFT response
  38. Possible GRB050528: no candidate from Liverpool Telescope
  39. GRB050525a: Radio Observations
  40. GRB 050509b: refined XRT/Chandra afterglow position analysis
  41. GRB 050525: RTT150, Optical observations
  42. GRB 050525a: SARA Observations
  43. GRB 050525B: Swift-BAT observations
  44. GRB 050525: MITSuME Optical Observation in VRI
  45. GRB050525A,optical observation
  46. GRB050525: Super-LOTIS observations
  47. GRB 050525, spectral lag pseudo-redshift
  48. GRB050306: optical afterglow not confirmed
  49. GRB 050525: BART optical observation
  50. GRB 050525A: BOOTES simultaneous optical observations
  51. GRB 050525A: Swift-BAT refined analysis
  52. GRB050525: Optical observations
  53. GRB 050525B: INTEGRAL shows it is unrelated to GRB050525A
  54. Konus-Wind observation of GRB 050525
  55. GRB 050525: TAROT observations of the early afterglow
  56. INTEGRAL detection of GRB 050525
  57. GRB 050525, infrared observations
  58. GRB 050525: observatons of the optical afterglow
  59. GRB050525: ROTSE-III Refined Analysis
  60. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  61. XRF050522: Radio Observations
  62. Swift/UVOT observation of XRF 050522
  63. GRB 050509A: Further I-band imaging
  64. GRB050522,optical observation
  65. GRB050520,optical observation
  66. XRF 050522: Continued NIR P200 Monitoring
  67. RBO Observations of GRB050522
  68. Recent GRB BVRcIc field photometry
  69. GRB050520: Radio Observations
  70. XRF 050522: Swift XRT observation
  71. XRF050522, BVRcIc field photometry
  72. XRF050522: Optical Observations
  73. XRF050522: Near-infrared Observations
  74. GRB 050520: VLT/ULTRACAM observations
  75. GRB 050520: Swift XRT refined analysis
  76. XRF050509C: Chandra Afterglow Detection
  77. XRF050509c: Radio Observations
  78. GRB 050520: P200 Observations
  79. GRB 050520: TAROT optical limit
  80. GRB 050520: VLT/ULTRACAM observations
  81. XRF 050509c optical afterglow
  82. GRB 050509B and short GRB-SN association? (corrected)
  83. GRB 050509B and short GRB-SN association?
  84. GRB050502b: Early Observation
  85. GRB050509b, Bok telescope B-band imaging
  86. Refined Chandra analysis of GRB 050509b
  87. GRB050509b, SDSS pre-burst observations
  88. GRB 050509b: Keck/Chandra Cross-Correlation
  89. GRB 050509b: Keck/Chandra Cross-Correlation
  90. Chandra observation of GRB 050509b
  91. GRB 050509b: RAPTOR deep, early limits.
  92. GRB050509B: Optical observations at the Very Large Telescope
  93. GRB 050509b: No Optical Variability in XRT Error Circle
  94. GRB 050509a: Swift-BAT refined analysis
  95. GRB 050509c: ROTSE-III Optical Limits
  96. GRB 050505, early TAROT observation
  97. GRB050509c: REM NIR and Optical observations
  98. GRB 050509b: Physical Properties of the Candidate Host galaxy
  99. GRB 050505: SARA Observations
  100. GRB 050509B, Optical Observations

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