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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"

28050 results found.

  1. GRB 050525: RTT150, Optical observations
  2. GRB 050525a: SARA Observations
  3. GRB 050525B: Swift-BAT observations
  4. GRB 050525: MITSuME Optical Observation in VRI
  5. GRB050525A,optical observation
  6. GRB050525: Super-LOTIS observations
  7. GRB 050525, spectral lag pseudo-redshift
  8. GRB050306: optical afterglow not confirmed
  9. GRB 050525: BART optical observation
  10. GRB 050525A: BOOTES simultaneous optical observations
  11. GRB 050525A: Swift-BAT refined analysis
  12. GRB050525: Optical observations
  13. GRB 050525B: INTEGRAL shows it is unrelated to GRB050525A
  14. Konus-Wind observation of GRB 050525
  15. GRB 050525: TAROT observations of the early afterglow
  16. INTEGRAL detection of GRB 050525
  17. GRB 050525, infrared observations
  18. GRB 050525: observatons of the optical afterglow
  19. GRB050525: ROTSE-III Refined Analysis
  20. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  21. XRF050522: Radio Observations
  22. Swift/UVOT observation of XRF 050522
  23. GRB 050509A: Further I-band imaging
  24. GRB050522,optical observation
  25. GRB050520,optical observation
  26. XRF 050522: Continued NIR P200 Monitoring
  27. RBO Observations of GRB050522
  28. Recent GRB BVRcIc field photometry
  29. GRB050520: Radio Observations
  30. XRF 050522: Swift XRT observation
  31. XRF050522, BVRcIc field photometry
  32. XRF050522: Optical Observations
  33. XRF050522: Near-infrared Observations
  34. GRB 050520: VLT/ULTRACAM observations
  35. GRB 050520: Swift XRT refined analysis
  36. XRF050509C: Chandra Afterglow Detection
  37. XRF050509c: Radio Observations
  38. GRB 050520: P200 Observations
  39. GRB 050520: TAROT optical limit
  40. GRB 050520: VLT/ULTRACAM observations
  41. XRF 050509c optical afterglow
  42. GRB 050509B and short GRB-SN association? (corrected)
  43. GRB 050509B and short GRB-SN association?
  44. GRB050502b: Early Observation
  45. GRB050509b, Bok telescope B-band imaging
  46. Refined Chandra analysis of GRB 050509b
  47. GRB050509b, SDSS pre-burst observations
  48. GRB 050509b: Keck/Chandra Cross-Correlation
  49. GRB 050509b: Keck/Chandra Cross-Correlation
  50. Chandra observation of GRB 050509b
  51. GRB 050509b: RAPTOR deep, early limits.
  52. GRB050509B: Optical observations at the Very Large Telescope
  53. GRB 050509b: No Optical Variability in XRT Error Circle
  54. GRB 050509a: Swift-BAT refined analysis
  55. GRB 050509c: ROTSE-III Optical Limits
  56. GRB 050505, early TAROT observation
  57. GRB050509c: REM NIR and Optical observations
  58. GRB 050509b: Physical Properties of the Candidate Host galaxy
  59. GRB 050505: SARA Observations
  60. GRB 050509B, Optical Observations
  61. GRB 050509B: Swift/XRT refined analysis
  62. GRB 050509b: Optical observations
  63. GRB 050509A: Optical observations
  64. GRB050509b: Radio Observations
  65. GRB 050509b: PAIRITEL and WIYN Observations
  66. GRB 050509b: Swift-BAT refined analysis of the short hard burst
  67. Swift Detection of GRB050509b: A short duration burst
  68. Swift Detection of the Burst GRB050509
  69. GRB 050505: early time observations
  70. GRB 050505, simultaneous optical observation
  71. GRB050505: AAVSO observations
  72. GRB050416A : 1 GHz limit from GMRT
  73. GRB050505: Optical Afterglow Candidate
  74. GRB050505 Swift-BAT refined analysis
  75. GRB 050416b:Swift XRT afterglow upper limits
  76. GRB 050416b:Swift XRT afterglow upper limits
  77. GRB050502b: Afterglow Confirmation: Correction to OT Coordinates
  78. GRB050502b: Afterglow Confirmation
  79. GRB050502: P200 Observations (Correction)
  80. GRB050502: P200 Observations
  81. GRB 050504 : R band observation at Lulin observatory
  82. Swift UVOT observation of GRB 050504
  83. GRB 050504, R band Observations
  84. GRB 050502b, V band Observations
  85. GRB050504: P60 Observations
  86. GRB 050504: A long GRB detected with INTEGRAL
  87. GRB (?) 050504: IR Observations, Intriguing Source
  88. GRB 050502b, Optical observations
  89. GRB050502a: P60 Observations (Correction)
  90. GRB050502a: P60 Observations
  91. Renewal of SGR 1806-20 activity
  92. GRB050502B Swift-BAT refined analysis
  93. Swift UVOT refined analysis
  94. GRB 050502a : R band observation at Lulin observatory
  95. GRB 050502b : optical observation at Lulin observatory
  96. GRB 050502A: Redshift measurement based on Keck HIRES Observations
  97. Swift Detection of the Bright Burst GRB050502b
  98. GRB 050502: INTEGRAL results
  99. GRB 050502: ROTSE-III Detection of Possible Counterpart
  100. Swift/BAT possible detection of a weak burst GRB050430

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