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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"

24892 results found.

  1. GRB050712: UVOT candidate optical counterpart
  2. GRB 050709: LCO40 Observations
  3. GRB050709, optical observations
  4. PROMPT Rc Observations of GRB 050709
  5. GRB 050525a: PROMPT VRcIc Detections
  6. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  7. GRB 050525a: ARC 3.5-Meter SPIcam Field Calibration
  8. GRB 050626: Swift XRT observations
  9. GRB 050408: ARC 3.5-meter NIR Observations
  10. GRB 050701: Refined XRT analysis
  11. Swift UVOT observations of GRB 050701
  12. GRB050701: Swift-BAT Refined analysis
  13. Swift trigger 143708 is really GRB 050701
  14. GRB 050607, radio observations
  15. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  16. GRB050525a: HST Observations
  17. H3800 and H3801 on 2005 June 11: two bursts from SGR1806-20 localized by HETE
  18. XRF 050509c: Optical monitoring
  19. Konus-Wind observation of an intermediate burst from SGR 1806-20
  20. XRF050509c: Radio Detection
  21. GRB 050607 optical decay
  22. GRB050607: refined analysis of prompt REM observations
  23. GRB 050607: PROMPT VRcIc Observations
  24. GRB 050607: Optical decay and spectral slope
  25. GRB050607,optical observation
  26. Optical Afterglow of GRB 050607
  27. GRB050607: Swift Detection of a long GRB
  28. GRB050607: prompt REM observations
  29. Limits on a SN in the field of GRB 050509b
  30. GRB 050603 - XRT data analysis of the first day
  31. GRB050603, submillimetre observations
  32. GRB050603: Radio Detection
  33. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  34. GRB 050603: INTEGRAL shows it is not a short GRB
  35. GRB 050525a, infrared observations
  36. GRB050528, XRT observations
  37. GRB050528: updated Liverpool Telescope limits
  38. Swift-BAT GRB 050528: a soft burst
  39. GRB050504: Ashra-P2/3 monitor and Ashra-AFT response
  40. Possible GRB050528: no candidate from Liverpool Telescope
  41. GRB050525a: Radio Observations
  42. GRB 050509b: refined XRT/Chandra afterglow position analysis
  43. GRB 050525: RTT150, Optical observations
  44. GRB 050525a: SARA Observations
  45. GRB 050525B: Swift-BAT observations
  46. GRB 050525: MITSuME Optical Observation in VRI
  47. GRB050525A,optical observation
  48. GRB050525: Super-LOTIS observations
  49. GRB 050525, spectral lag pseudo-redshift
  50. GRB050306: optical afterglow not confirmed
  51. GRB 050525: BART optical observation
  52. GRB 050525A: BOOTES simultaneous optical observations
  53. GRB 050525A: Swift-BAT refined analysis
  54. GRB050525: Optical observations
  55. GRB 050525B: INTEGRAL shows it is unrelated to GRB050525A
  56. Konus-Wind observation of GRB 050525
  57. GRB 050525: TAROT observations of the early afterglow
  58. INTEGRAL detection of GRB 050525
  59. GRB 050525, infrared observations
  60. GRB 050525: observatons of the optical afterglow
  61. GRB050525: ROTSE-III Refined Analysis
  62. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  63. XRF050522: Radio Observations
  64. Swift/UVOT observation of XRF 050522
  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. Recent GRB BVRcIc field photometry
  71. GRB050520: Radio Observations
  72. XRF 050522: Swift XRT observation
  73. XRF050522, BVRcIc field photometry
  74. XRF050522: Optical Observations
  75. XRF050522: Near-infrared Observations
  76. GRB 050520: VLT/ULTRACAM observations
  77. GRB 050520: Swift XRT refined analysis
  78. XRF050509C: Chandra Afterglow Detection
  79. XRF050509c: Radio Observations
  80. GRB 050520: P200 Observations
  81. GRB 050520: TAROT optical limit
  82. GRB 050520: VLT/ULTRACAM observations
  83. XRF 050509c optical afterglow
  84. GRB 050509B and short GRB-SN association? (corrected)
  85. GRB 050509B and short GRB-SN association?
  86. GRB050502b: Early Observation
  87. GRB050509b, Bok telescope B-band imaging
  88. Refined Chandra analysis of GRB 050509b
  89. GRB050509b, SDSS pre-burst observations
  90. GRB 050509b: Keck/Chandra Cross-Correlation
  91. GRB 050509b: Keck/Chandra Cross-Correlation
  92. Chandra observation of GRB 050509b
  93. GRB 050509b: RAPTOR deep, early limits.
  94. GRB050509B: Optical observations at the Very Large Telescope
  95. GRB 050509b: No Optical Variability in XRT Error Circle
  96. GRB 050509a: Swift-BAT refined analysis
  97. GRB 050509c: ROTSE-III Optical Limits
  98. GRB 050505, early TAROT observation
  99. GRB050509c: REM NIR and Optical observations
  100. GRB 050509b: Physical Properties of the Candidate Host galaxy

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