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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"

24949 results found.

  1. GRB 050525a: SARA Observations
  2. GRB 050525B: Swift-BAT observations
  3. GRB 050525: MITSuME Optical Observation in VRI
  4. GRB050525A,optical observation
  5. GRB050525: Super-LOTIS observations
  6. GRB 050525, spectral lag pseudo-redshift
  7. GRB050306: optical afterglow not confirmed
  8. GRB 050525: BART optical observation
  9. GRB 050525A: BOOTES simultaneous optical observations
  10. GRB 050525A: Swift-BAT refined analysis
  11. GRB050525: Optical observations
  12. GRB 050525B: INTEGRAL shows it is unrelated to GRB050525A
  13. Konus-Wind observation of GRB 050525
  14. GRB 050525: TAROT observations of the early afterglow
  15. INTEGRAL detection of GRB 050525
  16. GRB 050525, infrared observations
  17. GRB 050525: observatons of the optical afterglow
  18. GRB050525: ROTSE-III Refined Analysis
  19. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  20. XRF050522: Radio Observations
  21. Swift/UVOT observation of XRF 050522
  22. GRB 050509A: Further I-band imaging
  23. GRB050522,optical observation
  24. GRB050520,optical observation
  25. XRF 050522: Continued NIR P200 Monitoring
  26. RBO Observations of GRB050522
  27. Recent GRB BVRcIc field photometry
  28. GRB050520: Radio Observations
  29. XRF 050522: Swift XRT observation
  30. XRF050522, BVRcIc field photometry
  31. XRF050522: Optical Observations
  32. XRF050522: Near-infrared Observations
  33. GRB 050520: VLT/ULTRACAM observations
  34. GRB 050520: Swift XRT refined analysis
  35. XRF050509C: Chandra Afterglow Detection
  36. XRF050509c: Radio Observations
  37. GRB 050520: P200 Observations
  38. GRB 050520: TAROT optical limit
  39. GRB 050520: VLT/ULTRACAM observations
  40. XRF 050509c optical afterglow
  41. GRB 050509B and short GRB-SN association? (corrected)
  42. GRB 050509B and short GRB-SN association?
  43. GRB050502b: Early Observation
  44. GRB050509b, Bok telescope B-band imaging
  45. Refined Chandra analysis of GRB 050509b
  46. GRB050509b, SDSS pre-burst observations
  47. GRB 050509b: Keck/Chandra Cross-Correlation
  48. GRB 050509b: Keck/Chandra Cross-Correlation
  49. Chandra observation of GRB 050509b
  50. GRB 050509b: RAPTOR deep, early limits.
  51. GRB050509B: Optical observations at the Very Large Telescope
  52. GRB 050509b: No Optical Variability in XRT Error Circle
  53. GRB 050509a: Swift-BAT refined analysis
  54. GRB 050509c: ROTSE-III Optical Limits
  55. GRB 050505, early TAROT observation
  56. GRB050509c: REM NIR and Optical observations
  57. GRB 050509b: Physical Properties of the Candidate Host galaxy
  58. GRB 050505: SARA Observations
  59. GRB 050509B, Optical Observations
  60. GRB 050509B: Swift/XRT refined analysis
  61. GRB 050509b: Optical observations
  62. GRB 050509A: Optical observations
  63. GRB050509b: Radio Observations
  64. GRB 050509b: PAIRITEL and WIYN Observations
  65. GRB 050509b: Swift-BAT refined analysis of the short hard burst
  66. Swift Detection of GRB050509b: A short duration burst
  67. Swift Detection of the Burst GRB050509
  68. GRB 050505: early time observations
  69. GRB 050505, simultaneous optical observation
  70. GRB050505: AAVSO observations
  71. GRB050416A : 1 GHz limit from GMRT
  72. GRB050505: Optical Afterglow Candidate
  73. GRB050505 Swift-BAT refined analysis
  74. GRB 050416b:Swift XRT afterglow upper limits
  75. GRB 050416b:Swift XRT afterglow upper limits
  76. GRB050502b: Afterglow Confirmation: Correction to OT Coordinates
  77. GRB050502b: Afterglow Confirmation
  78. GRB050502: P200 Observations (Correction)
  79. GRB050502: P200 Observations
  80. GRB 050504 : R band observation at Lulin observatory
  81. Swift UVOT observation of GRB 050504
  82. GRB 050504, R band Observations
  83. GRB 050502b, V band Observations
  84. GRB050504: P60 Observations
  85. GRB 050504: A long GRB detected with INTEGRAL
  86. GRB (?) 050504: IR Observations, Intriguing Source
  87. GRB 050502b, Optical observations
  88. GRB050502a: P60 Observations (Correction)
  89. GRB050502a: P60 Observations
  90. Renewal of SGR 1806-20 activity
  91. GRB050502B Swift-BAT refined analysis
  92. Swift UVOT refined analysis
  93. GRB 050502a : R band observation at Lulin observatory
  94. GRB 050502b : optical observation at Lulin observatory
  95. GRB 050502A: Redshift measurement based on Keck HIRES Observations
  96. Swift Detection of the Bright Burst GRB050502b
  97. GRB 050502: INTEGRAL results
  98. GRB 050502: ROTSE-III Detection of Possible Counterpart
  99. Swift/BAT possible detection of a weak burst GRB050430
  100. GRB050416a: Radio Detection

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