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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"

19386 results found.

  1. GRB 050713A XMM-Newton observation
  2. GRB050713B: Faulkes North Telescope observation
  3. RBO RI observations of GRB 050713A
  4. GRB050709 : Chandra source optical counterpart
  5. GRB 050712, optical observations
  6. GRB050709: Candidate X-ray Afterglow from Chandra
  7. GRB050713: possible I-band afterglow
  8. GRB 050713A: ROTSE-III Optical Limits
  9. GRB050709: Radio Observations
  10. GRB 050709: Swift UVOT and XRT observations
  11. GRB050712: UVOT candidate optical counterpart
  12. GRB 050712: Swift detection of a weak burst
  13. GRB 050709: LCO40 Observations
  14. PROMPT Rc Observations of GRB 050709
  15. GRB 050525a: PROMPT VRcIc Detections
  16. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  17. GRB 050525a: ARC 3.5-Meter SPIcam Field Calibration
  18. GRB 050408: ARC 3.5-meter NIR Observations
  19. Swift UVOT observations of GRB 050701
  20. GRB 050607, radio observations
  21. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  22. GRB050525a: HST Observations
  23. XRF 050509c: Optical monitoring
  24. XRF050509c: Radio Detection
  25. GRB 050607 optical decay
  26. GRB050607: refined analysis of prompt REM observations
  27. GRB 050607: PROMPT VRcIc Observations
  28. GRB 050607: Optical decay and spectral slope
  29. GRB050607,optical observation
  30. GRB 050607 - XRT refined data analysis
  31. Optical Afterglow of GRB 050607
  32. GRB050607: Swift Detection of a long GRB
  33. GRB050607: prompt REM observations
  34. Limits on a SN in the field of GRB 050509b
  35. GRB 050603: Redshift
  36. GRB 050603 - XRT data analysis of the first day
  37. Konus-Wind observation of GRB 050603
  38. GRB050603, submillimetre observations
  39. GRB050603: Radio Detection
  40. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  41. GRB 050603: INTEGRAL shows it is not a short GRB
  42. GRB 050525a, infrared observations
  43. GRB050528: updated Liverpool Telescope limits
  44. GRB050504: Ashra-P2/3 monitor and Ashra-AFT response
  45. Possible GRB050528: no candidate from Liverpool Telescope
  46. GRB050525a: Radio Observations
  47. GRB 050509b: refined XRT/Chandra afterglow position analysis
  48. GRB 050525: RTT150, Optical observations
  49. GRB 050525a: SARA Observations
  50. GRB 050525B: Swift-BAT observations
  51. GRB 050525: MITSuME Optical Observation in VRI
  52. GRB050525A,optical observation
  53. GRB050525: Super-LOTIS observations
  54. GRB050306: optical afterglow not confirmed
  55. GRB 050525: BART optical observation
  56. GRB 050525A: BOOTES simultaneous optical observations
  57. GRB 050525A: Swift-BAT refined analysis
  58. GRB050525: Optical observations
  59. GRB 050525B: INTEGRAL shows it is unrelated to GRB050525A
  60. Konus-Wind observation of GRB 050525
  61. GRB 050525: TAROT observations of the early afterglow
  62. INTEGRAL detection of GRB 050525
  63. GRB 050525, infrared observations
  64. GRB 050525: observatons of the optical afterglow
  65. GRB050525: ROTSE-III Refined Analysis
  66. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  67. XRF 050522: Swift XRT refined analysis
  68. XRF050522: Radio Observations
  69. Swift/UVOT observation of XRF 050522
  70. GRB 050509A: Further I-band imaging
  71. GRB050522,optical observation
  72. GRB050520,optical observation
  73. XRF 050522: Continued NIR P200 Monitoring
  74. Recent GRB BVRcIc field photometry
  75. GRB050520: Radio Observations
  76. XRF 050522: Swift XRT observation
  77. XRF050522, BVRcIc field photometry
  78. XRF050522: Optical Observations
  79. XRF050522: Near-infrared Observations
  80. GRB 050520: VLT/ULTRACAM observations
  81. Swift UVOT Observations of GRB 050520
  82. GRB 050520: Swift XRT refined analysis
  83. XRF050509c: Radio Observations
  84. RBO Observations of GRB050520
  85. GRB 050520: P200 Observations
  86. GRB 050520: TAROT optical limit
  87. GRB 050520: Swift XRT position
  88. GRB 050520: VLT/ULTRACAM observations
  89. GRB 050509B and short GRB-SN association? (corrected)
  90. GRB 050509B and short GRB-SN association?
  91. GRB050502b: Early Observation
  92. GRB050509b, Bok telescope B-band imaging
  93. GRB050509b, SDSS pre-burst observations
  94. GRB 050509b: Keck/Chandra Cross-Correlation
  95. GRB 050509b: Keck/Chandra Cross-Correlation
  96. Chandra observation of GRB 050509b
  97. GRB 050509b: RAPTOR deep, early limits.
  98. GRB050509B: Optical observations at the Very Large Telescope
  99. GRB 050509b: No Optical Variability in XRT Error Circle
  100. GRB 050509c: ROTSE-III Optical Limits

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