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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"

28052 results found.

  1. GRB050525a: Radio Observations
  2. GRB 050509b: refined XRT/Chandra afterglow position analysis
  3. GRB 050525: RTT150, Optical observations
  4. GRB 050525a: SARA Observations
  5. GRB 050525B: Swift-BAT observations
  6. GRB 050525: MITSuME Optical Observation in VRI
  7. GRB050525A,optical observation
  8. GRB050525: Super-LOTIS observations
  9. GRB 050525, spectral lag pseudo-redshift
  10. GRB050306: optical afterglow not confirmed
  11. GRB 050525: BART optical observation
  12. GRB 050525A: BOOTES simultaneous optical observations
  13. GRB 050525A: Swift-BAT refined analysis
  14. GRB050525: Optical observations
  15. GRB 050525B: INTEGRAL shows it is unrelated to GRB050525A
  16. Konus-Wind observation of GRB 050525
  17. GRB 050525: TAROT observations of the early afterglow
  18. INTEGRAL detection of GRB 050525
  19. GRB 050525, infrared observations
  20. GRB 050525: observatons of the optical afterglow
  21. GRB050525: ROTSE-III Refined Analysis
  22. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  23. XRF050522: Radio Observations
  24. Swift/UVOT observation of XRF 050522
  25. GRB 050509A: Further I-band imaging
  26. GRB050522,optical observation
  27. GRB050520,optical observation
  28. XRF 050522: Continued NIR P200 Monitoring
  29. RBO Observations of GRB050522
  30. Recent GRB BVRcIc field photometry
  31. GRB050520: Radio Observations
  32. XRF 050522: Swift XRT observation
  33. XRF050522, BVRcIc field photometry
  34. XRF050522: Optical Observations
  35. XRF050522: Near-infrared Observations
  36. GRB 050520: VLT/ULTRACAM observations
  37. GRB 050520: Swift XRT refined analysis
  38. XRF050509C: Chandra Afterglow Detection
  39. XRF050509c: Radio Observations
  40. GRB 050520: P200 Observations
  41. GRB 050520: TAROT optical limit
  42. GRB 050520: VLT/ULTRACAM observations
  43. XRF 050509c optical afterglow
  44. GRB 050509B and short GRB-SN association? (corrected)
  45. GRB 050509B and short GRB-SN association?
  46. GRB050502b: Early Observation
  47. GRB050509b, Bok telescope B-band imaging
  48. Refined Chandra analysis of GRB 050509b
  49. GRB050509b, SDSS pre-burst observations
  50. GRB 050509b: Keck/Chandra Cross-Correlation
  51. GRB 050509b: Keck/Chandra Cross-Correlation
  52. Chandra observation of GRB 050509b
  53. GRB 050509b: RAPTOR deep, early limits.
  54. GRB050509B: Optical observations at the Very Large Telescope
  55. GRB 050509b: No Optical Variability in XRT Error Circle
  56. GRB 050509a: Swift-BAT refined analysis
  57. GRB 050509c: ROTSE-III Optical Limits
  58. GRB 050505, early TAROT observation
  59. GRB050509c: REM NIR and Optical observations
  60. GRB 050509b: Physical Properties of the Candidate Host galaxy
  61. GRB 050505: SARA Observations
  62. GRB 050509B, Optical Observations
  63. GRB 050509B: Swift/XRT refined analysis
  64. GRB 050509b: Optical observations
  65. GRB 050509A: Optical observations
  66. GRB050509b: Radio Observations
  67. GRB 050509b: PAIRITEL and WIYN Observations
  68. GRB 050509b: Swift-BAT refined analysis of the short hard burst
  69. Swift Detection of GRB050509b: A short duration burst
  70. Swift Detection of the Burst GRB050509
  71. GRB 050505: early time observations
  72. GRB 050505, simultaneous optical observation
  73. GRB050505: AAVSO observations
  74. GRB050416A : 1 GHz limit from GMRT
  75. GRB050505: Optical Afterglow Candidate
  76. GRB050505 Swift-BAT refined analysis
  77. GRB 050416b:Swift XRT afterglow upper limits
  78. GRB 050416b:Swift XRT afterglow upper limits
  79. GRB050502b: Afterglow Confirmation: Correction to OT Coordinates
  80. GRB050502b: Afterglow Confirmation
  81. GRB050502: P200 Observations (Correction)
  82. GRB050502: P200 Observations
  83. GRB 050504 : R band observation at Lulin observatory
  84. Swift UVOT observation of GRB 050504
  85. GRB 050504, R band Observations
  86. GRB 050502b, V band Observations
  87. GRB050504: P60 Observations
  88. GRB 050504: A long GRB detected with INTEGRAL
  89. GRB (?) 050504: IR Observations, Intriguing Source
  90. GRB 050502b, Optical observations
  91. GRB050502a: P60 Observations (Correction)
  92. GRB050502a: P60 Observations
  93. Renewal of SGR 1806-20 activity
  94. GRB050502B Swift-BAT refined analysis
  95. Swift UVOT refined analysis
  96. GRB 050502a : R band observation at Lulin observatory
  97. GRB 050502b : optical observation at Lulin observatory
  98. GRB 050502A: Redshift measurement based on Keck HIRES Observations
  99. Swift Detection of the Bright Burst GRB050502b
  100. GRB 050502: INTEGRAL results

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