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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"

37527 results found.

  1. GRB 050603 - XRT data analysis of the first day
  2. Konus-Wind observation of GRB 050603
  3. GRB 050603: Analysis of UVOT data
  4. GRB 050603: Swift XRT Position
  5. GRB050603: Radio Detection
  6. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  7. GRB 050603: Afterglow Identification from LCO
  8. GRB 050603: INTEGRAL shows it is not a short GRB
  9. GRB 050408: jet break in the XRT light curve
  10. GRB 050525a, infrared observations
  11. GRB 050525a, SMARTS optical/IR afterglow observations
  12. Correction to GCN Circ 3502 on GRB 050528
  13. GRB050528: updated Liverpool Telescope limits
  14. Swift-BAT GRB 050528: a soft burst
  15. Update on Swift-BAT GRB 050528 (Trigger 130679)
  16. GRB050528: BOOTES optical candidate (retraction)
  17. GRB050504: Ashra-P2/3 monitor and Ashra-AFT response
  18. GRB050528: BOOTES optical candidate
  19. Possible GRB050528: no candidate from Liverpool Telescope
  20. Swift-BAT detection of possible GRB 050528
  21. GRB050525a: Radio Observations
  22. GRB 050509b: refined XRT/Chandra afterglow position analysis
  23. GRB 050525: RTT150, Optical observations
  24. GRB050525a: optical upper limits
  25. GRB 050525a: SARA Observations
  26. GRB 050525B: Swift-BAT observations
  27. GRB 050525: MITSuME Optical Observation in VRI
  28. GRB 050525a: MDM Observations
  29. GRB050525A,optical observation
  30. GRB 050525 : Lulin optical afterglow observations
  31. GRB050525: Super-LOTIS observations
  32. GRB 050525, spectral lag pseudo-redshift
  33. GRB 050525a: Gemini/GMOS Spectra
  34. GRB050306: optical afterglow not confirmed
  35. GRB 050525: BART optical observation
  36. GRB 050525A: BOOTES simultaneous optical observations
  37. GRB 050525A: Swift-BAT refined analysis
  38. GRB050525: Optical observations
  39. GRB 050525B: INTEGRAL shows it is unrelated to GRB050525A
  40. GRB 050525: pseudo-redshift
  41. Swift/UVOT UV and optical detections of GRB 050525
  42. Konus-Wind observation of GRB 050525
  43. GRB 050525: TAROT observations of the early afterglow
  44. INTEGRAL detection of GRB 050525
  45. GRB 050525, infrared observations
  46. GRB 050525: Optical observation
  47. GRB 050525: observatons of the optical afterglow
  48. GRB050525: ROTSE-III Refined Analysis
  49. GRB 050525 - Very Bright, Not Short
  50. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  51. GRB 050525A: ROTSE-III Detection of Possible Counterpart
  52. XRF050522: NIR observations of XRT candidate
  53. XRF050522: Radio Observations
  54. GRB 050509A: Further I-band imaging
  55. GRB050522,optical observation
  56. GRB050520,optical observation
  57. XRF 050522: Continued NIR P200 Monitoring
  58. RBO Observations of GRB050522
  59. GRB050509b: optical observations
  60. Recent GRB BVRcIc field photometry
  61. GRB050520: Radio Observations
  62. XRF050522, BVRcIc field photometry
  63. XRF050522: Optical Observations
  64. XRF 050522: KAIT observations
  65. XRF 050522 detected with INTEGRAL
  66. GRB 050520: VLT/ULTRACAM observations
  67. Swift UVOT Observations of GRB 050520
  68. GRB 050520: Swift XRT refined analysis
  69. RBO Observations of GRB050520
  70. GRB 050520: P200 Observations
  71. GRB050520: Liverpool Telescope follow-up
  72. GRB 050520: TAROT optical limit
  73. GRB 050520: Swift XRT position
  74. GRB 050520: VLT/ULTRACAM observations
  75. GRB 050520: OSN optical observations
  76. GRB 050520: BART optical limit
  77. GRB 050520 - A long GRB detected with INTEGRAL
  78. Swift-BAT trigger 122203 is not a real GRB
  79. GRB 050504: Swift XRT afterglow candidate has faded
  80. XRF 050509c optical afterglow
  81. GRB 050509B and short GRB-SN association? (corrected)
  82. GRB 050509B and short GRB-SN association?
  83. GRB 050509B: Subaru Optical Observations
  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/Infared observations
  93. GRB 050509b: Swift/UVOT follow-up measurements
  94. GRB 050509b Milagro GeV/TeV Observations
  95. GRB050509B: Optical observations at the Very Large Telescope
  96. GRB 050509b: No Optical Variability in XRT Error Circle
  97. GRB 050509a: Swift-BAT refined analysis
  98. GRB 050509c: ROTSE-III Optical Limits
  99. GRB 050509B: WSRT Radio Observations
  100. GRB050509c: REM NIR and Optical observations (errata corrige to GCN 3400)

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