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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"
  1. Update on Swift-BAT GRB 050528 (Trigger 130679)
  2. GRB050528: BOOTES optical candidate (retraction)
  3. GRB050504: Ashra-P2/3 monitor and Ashra-AFT response
  4. GRB050528: BOOTES optical candidate
  5. Possible GRB050528: no candidate from Liverpool Telescope
  6. Swift-BAT detection of possible GRB 050528
  7. GRB050525a: Radio Observations
  8. GRB 050509b: refined XRT/Chandra afterglow position analysis
  9. GRB 050525: RTT150, Optical observations
  10. GRB050525a: optical upper limits
  11. GRB 050525a: SARA Observations
  12. GRB 050525B: Swift-BAT observations
  13. GRB 050525: MITSuME Optical Observation in VRI
  14. GRB 050525a: MDM Observations
  15. GRB050525A,optical observation
  16. GRB 050525 : Lulin optical afterglow observations
  17. GRB050525: Super-LOTIS observations
  18. GRB 050525, spectral lag pseudo-redshift
  19. GRB 050525a: Gemini/GMOS Spectra
  20. GRB050306: optical afterglow not confirmed
  21. GRB 050525: BART optical observation
  22. GRB 050525A: BOOTES simultaneous optical observations
  23. GRB 050525A: Swift-BAT refined analysis
  24. GRB050525: Optical observations
  25. GRB 050525B: INTEGRAL shows it is unrelated to GRB050525A
  26. GRB 050525: pseudo-redshift
  27. Swift/UVOT UV and optical detections of GRB 050525
  28. Konus-Wind observation of GRB 050525
  29. GRB 050525: TAROT observations of the early afterglow
  30. INTEGRAL detection of GRB 050525
  31. GRB 050525, infrared observations
  32. GRB 050525: Optical observation
  33. GRB 050525: observatons of the optical afterglow
  34. GRB050525: ROTSE-III Refined Analysis
  35. GRB 050525 - Very Bright, Not Short
  36. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  37. GRB 050525A: ROTSE-III Detection of Possible Counterpart
  38. XRF050522: NIR observations of XRT candidate
  39. XRF 050522: Swift XRT refined analysis
  40. XRF050522: Radio Observations
  41. Swift/UVOT observation of XRF 050522
  42. GRB 050509A: Further I-band imaging
  43. GRB050522,optical observation
  44. GRB050520,optical observation
  45. XRF 050522: Continued NIR P200 Monitoring
  46. RBO Observations of GRB050522
  47. GRB050509b: optical observations
  48. Recent GRB BVRcIc field photometry
  49. GRB050520: Radio Observations
  50. XRF 050522: Swift XRT observation
  51. XRF050522, BVRcIc field photometry
  52. XRF 050522 : Lulin observations
  53. XRF050522: Optical Observations
  54. XRF050522: Near-infrared Observations
  55. XRF 050522: KAIT observations
  56. XRF 050522 detected with INTEGRAL
  57. GRB 050520: VLT/ULTRACAM observations
  58. Swift UVOT Observations of GRB 050520
  59. GRB 050520: Swift XRT refined analysis
  60. XRF050509C: Chandra Afterglow Detection
  61. XRF 050509c: Swift XRT Upper Limit
  62. XRF050509c: Radio Observations
  63. RBO Observations of GRB050520
  64. GRB 050520: P200 Observations
  65. GRB050520: Liverpool Telescope follow-up
  66. RBO Observations of GRB050520
  67. GRB 050520: TAROT optical limit
  68. GRB 050520: Swift XRT position
  69. GRB 050520: VLT/ULTRACAM observations
  70. GRB 050520: OSN optical observations
  71. GRB 050520: BART optical limit
  72. GRB 050520 - A long GRB detected with INTEGRAL
  73. No Swift-BAT Lightcurves in real-time for next 3 weeks
  74. Swift-BAT trigger 122203 is not a real GRB
  75. XRF 050509C: REM NIR and Optical refined analysis
  76. GRB 050504: Swift XRT afterglow candidate has faded
  77. XRF 050509c optical afterglow
  78. GRB 050509B and short GRB-SN association? (corrected)
  79. GRB 050509B and short GRB-SN association?
  80. GRB 050509B: Subaru Optical Observations
  81. GRB050502b: Early Observation
  82. GRB050509b, Bok telescope B-band imaging
  83. Refined Chandra analysis of GRB 050509b
  84. GRB050509b, SDSS pre-burst observations
  85. GRB 050509b: Keck/Chandra Cross-Correlation
  86. GRB 050509b: Keck/Chandra Cross-Correlation
  87. Chandra observation of GRB 050509b
  88. GRB 050509b: RAPTOR deep, early limits.
  89. GRB050509B: Optical/Infared observations
  90. GRB 050509b: Swift/UVOT follow-up measurements
  91. GRB 050509b Milagro GeV/TeV Observations
  92. GRB050509B: Optical observations at the Very Large Telescope
  93. GRB 050509b: No Optical Variability in XRT Error Circle
  94. GRB050416: Afterglow detection at 188 nm with Swift UVOT
  95. GRB 050509a: Swift-BAT refined analysis
  96. GRB 050509c: ROTSE-III Optical Limits
  97. GRB 050509B: WSRT Radio Observations
  98. GRB050509c: REM NIR and Optical observations (errata corrige to GCN 3400)
  99. GRB 050505, early TAROT observation
  100. GRB050509c (=H3751): An X-Ray Flash Localized By HETE

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