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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"

36158 results found.

  1. GRB 050626 - Correction to GCN 3552
  2. GRB 050626 - a long GRB detected with INTEGRAL
  3. GRB 050525A: Swift Late-Time Decay Rate
  4. H3804: A Possible New XRB Detected by HETE
  5. XRF 050509c: Optical monitoring
  6. IBAS Alert #2512 is NOT a GRB
  7. GRB 050416(a): Host Galaxy Redshift Determination
  8. GRB 050607: MDM Observation
  9. GRB 050607 optical decay
  10. GRB 050607: RTT150 optical observations
  11. GRB 050607 : Lulin R-band observation
  12. GRB 050607: PROMPT VRcIc Observations
  13. GRB 050607: RAPTOR-S Early Optical Limits
  14. GRB 050525a, Mid-Infrared Observations
  15. GRB 050607: Optical decay and spectral slope
  16. GRB 050607: MDM Observations
  17. GRB050607,optical observation
  18. GRB 050607 - XRT refined data analysis
  19. Optical Afterglow of GRB 050607
  20. GRB050607 optical limit by "Pi of the Sky"
  21. GRB050607: Swift Detection of a long GRB
  22. GRB050607: P60 Observations
  23. GRB 050603: prediction of t_break
  24. Limits on a SN in the field of GRB 050509b
  25. GRB 050603: Redshift
  26. GRB 050603 - XRT data analysis of the first day
  27. Konus-Wind observation of GRB 050603
  28. GRB 050603: Analysis of UVOT data
  29. GRB 050603: Swift XRT Position
  30. GRB050603: Radio Detection
  31. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  32. GRB 050603: Afterglow Identification from LCO
  33. GRB 050603: INTEGRAL shows it is not a short GRB
  34. GRB 050408: jet break in the XRT light curve
  35. GRB 050525a, infrared observations
  36. GRB 050525a, SMARTS optical/IR afterglow observations
  37. Correction to GCN Circ 3502 on GRB 050528
  38. GRB050528: updated Liverpool Telescope limits
  39. Swift-BAT GRB 050528: a soft burst
  40. Update on Swift-BAT GRB 050528 (Trigger 130679)
  41. GRB050528: BOOTES optical candidate (retraction)
  42. GRB050504: Ashra-P2/3 monitor and Ashra-AFT response
  43. GRB050528: BOOTES optical candidate
  44. Possible GRB050528: no candidate from Liverpool Telescope
  45. Swift-BAT detection of possible GRB 050528
  46. GRB050525a: Radio Observations
  47. GRB 050509b: refined XRT/Chandra afterglow position analysis
  48. GRB 050525: RTT150, Optical observations
  49. GRB050525a: optical upper limits
  50. GRB 050525a: SARA Observations
  51. GRB 050525B: Swift-BAT observations
  52. GRB 050525: MITSuME Optical Observation in VRI
  53. GRB 050525a: MDM Observations
  54. GRB050525A,optical observation
  55. GRB 050525 : Lulin optical afterglow observations
  56. GRB050525: Super-LOTIS observations
  57. GRB 050525, spectral lag pseudo-redshift
  58. GRB 050525a: Gemini/GMOS Spectra
  59. GRB050306: optical afterglow not confirmed
  60. GRB 050525: BART optical observation
  61. GRB 050525A: BOOTES simultaneous optical observations
  62. GRB 050525A: Swift-BAT refined analysis
  63. GRB050525: Optical observations
  64. GRB 050525B: INTEGRAL shows it is unrelated to GRB050525A
  65. GRB 050525: pseudo-redshift
  66. Swift/UVOT UV and optical detections of GRB 050525
  67. Konus-Wind observation of GRB 050525
  68. GRB 050525: TAROT observations of the early afterglow
  69. INTEGRAL detection of GRB 050525
  70. GRB 050525, infrared observations
  71. GRB 050525: Optical observation
  72. GRB 050525: observatons of the optical afterglow
  73. GRB050525: ROTSE-III Refined Analysis
  74. GRB 050525 - Very Bright, Not Short
  75. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  76. GRB 050525A: ROTSE-III Detection of Possible Counterpart
  77. XRF050522: NIR observations of XRT candidate
  78. XRF050522: Radio Observations
  79. GRB 050509A: Further I-band imaging
  80. GRB050522,optical observation
  81. GRB050520,optical observation
  82. XRF 050522: Continued NIR P200 Monitoring
  83. RBO Observations of GRB050522
  84. GRB050509b: optical observations
  85. Recent GRB BVRcIc field photometry
  86. GRB050520: Radio Observations
  87. XRF050522, BVRcIc field photometry
  88. XRF050522: Optical Observations
  89. XRF 050522: KAIT observations
  90. XRF 050522 detected with INTEGRAL
  91. GRB 050520: VLT/ULTRACAM observations
  92. Swift UVOT Observations of GRB 050520
  93. GRB 050520: Swift XRT refined analysis
  94. RBO Observations of GRB050520
  95. GRB 050520: P200 Observations
  96. GRB050520: Liverpool Telescope follow-up
  97. GRB 050520: TAROT optical limit
  98. GRB 050520: Swift XRT position
  99. GRB 050520: VLT/ULTRACAM observations
  100. GRB 050520: OSN optical observations

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