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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').
Advanced Search

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"

35947 results found.

  1. GRB 050509B and short GRB-SN association? (corrected)
  2. GRB 050509B and short GRB-SN association?
  3. GRB 050509B: Subaru Optical Observations
  4. GRB050502b: Early Observation
  5. GRB050509b, Bok telescope B-band imaging
  6. Refined Chandra analysis of GRB 050509b
  7. GRB050509b, SDSS pre-burst observations
  8. GRB 050509b: Keck/Chandra Cross-Correlation
  9. GRB 050509b: Keck/Chandra Cross-Correlation
  10. Chandra observation of GRB 050509b
  11. GRB 050509b: RAPTOR deep, early limits.
  12. GRB050509B: Optical/Infared observations
  13. GRB 050509b: Swift/UVOT follow-up measurements
  14. GRB 050509b Milagro GeV/TeV Observations
  15. GRB050509B: Optical observations at the Very Large Telescope
  16. GRB 050509b: No Optical Variability in XRT Error Circle
  17. GRB 050509a: Swift-BAT refined analysis
  18. GRB 050509c: ROTSE-III Optical Limits
  19. GRB 050509B: WSRT Radio Observations
  20. GRB050509c: REM NIR and Optical observations (errata corrige to GCN 3400)
  21. GRB 050505, early TAROT observation
  22. GRB050509c (=H3751): An X-Ray Flash Localized By HETE
  23. GRB 050509b: Further Analysis of Keck LRIS Images
  24. GRB050509c: REM NIR and Optical observations
  25. GRB 050509b: Physical Properties of the Candidate Host galaxy
  26. GRB 050505: SARA Observations
  27. Swift UVOT Follow-up Observations of GRB 050509B
  28. GRB 050509B, Optical Observations
  29. GRB 050509B: Swift/XRT refined analysis
  30. GRB 050509b: Optical observations
  31. GRB 050509b: Precision Astrometry
  32. GRB 050509b: Possible Optical Counterpart
  33. Keck/DEIMOS Spectrum of Possible Host Galaxy for GRB050509b
  34. GRB 050509A: Optical observations
  35. GRB 050509b: Optical Counterpart Candidate
  36. GRB 050509b: PAIRITEL and WIYN Observations
  37. GRB 050509b: Swift-BAT refined analysis of the short hard burst
  38. GRB 050509b: optical observations
  39. GRB 050509b: Swift XRT Position
  40. GRB 050509B: ROTSE-III Optical Limits
  41. GRB 050509a: Swift XRT Position
  42. Swift-BAT detection of GRB 050507
  43. GRB 050505: Keck I-band Magnitude
  44. GRB 050505: early time observations
  45. GRB 050505 - Faulkes Telescope North observations
  46. GRB 050502a: Swift XRT Upper Limit
  47. GRB 050505, simultaneous optical observation
  48. GRB 050505: Further Swift UVOT observations.
  49. GRB050505: AAVSO observations
  50. GRB050416A : 1 GHz limit from GMRT
  51. GRB 050505: Keck absorption spectrum and redshift (z=4.27)
  52. GRB 050505 UVOT
  53. GRB050505: Optical Afterglow Candidate
  54. GRB 050505: Swift XRT Position
  55. GRB 050502a: Optical Observations
  56. GRB 050416b:Swift XRT afterglow upper limits
  57. GRB 050416b:Swift XRT afterglow upper limits
  58. GRB 050504: Swift XRT position
  59. GRB050502: P200 Observations (Correction)
  60. GRB050502: P200 Observations
  61. GRB 050504 : R band observation at Lulin observatory
  62. Swift UVOT observation of GRB 050504
  63. GRB 050504, R band Observations
  64. GRB 050502b, V band Observations
  65. GRB050504: P60 Observations
  66. GRB 050504: A long GRB detected with INTEGRAL
  67. GRB (?) 050504: IR Observations, Intriguing Source
  68. GRB 050502b, Optical observations
  69. GRB050502a: P60 Observations (Correction)
  70. GRB050502a: P60 Observations
  71. Renewal of SGR 1806-20 activity
  72. GRB 050502a: RBO Observations
  73. GRB 050502A: WSRT Radio Observations
  74. GRB050502A: Optical Observations
  75. Swift UVOT refined analysis
  76. Retraction of Swift-BAT trigger 116145
  77. GRB 050502a : R band observation at Lulin observatory
  78. GRB 050502b : optical observation at Lulin observatory
  79. GRB 050502b: Swift XRT Position
  80. GRB 050502A: Redshift measurement based on Keck HIRES Observations
  81. GRB 050502: INTEGRAL results
  82. GRB050502: ANU 1m optical Observations
  83. GRB 050502: Confirmed variability of the afterglow candidate +
  84. GRB 050502: PAIRITEL IR Observations
  85. GRB050502 - Correction on the Optical Candidate from the Liverpool
  86. GRB 050502 - A long GRB detected with INTEGRAL
  87. GRB 050502: ROTSE-III Detection of Possible Counterpart
  88. Swift-BAT Trigger 115881 is not a real GRB
  89. Swift/BAT possible detection of a weak burst GRB050430
  90. GRB 050401: Rc observation
  91. GRB050416a: Radio Detection
  92. GRB 050422: Swift-UVOT observation
  93. GRB 050422: Swift-BAT refined analysis
  94. GRB 050422: Swift XRT Position
  95. Swift Detection of GRB 050422
  96. GRB 050421: NIR observations
  97. GRB 050416: Optical/NIR observations
  98. GRB 050421: SLOTIS observations
  99. GRB 050421: Further Analysis of IR imaging
  100. GRB050421: Radio Observations

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