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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

37674 results found.

  1. GRB 050509A: Further I-band imaging
  2. GRB050522,optical observation
  3. GRB050520,optical observation
  4. XRF 050522: Continued NIR P200 Monitoring
  5. RBO Observations of GRB050522
  6. GRB050509b: optical observations
  7. Recent GRB BVRcIc field photometry
  8. GRB050520: Radio Observations
  9. XRF050522, BVRcIc field photometry
  10. XRF050522: Optical Observations
  11. XRF 050522: KAIT observations
  12. XRF 050522 detected with INTEGRAL
  13. GRB 050520: VLT/ULTRACAM observations
  14. Swift UVOT Observations of GRB 050520
  15. GRB 050520: Swift XRT refined analysis
  16. RBO Observations of GRB050520
  17. GRB 050520: P200 Observations
  18. GRB050520: Liverpool Telescope follow-up
  19. GRB 050520: TAROT optical limit
  20. GRB 050520: Swift XRT position
  21. GRB 050520: VLT/ULTRACAM observations
  22. GRB 050520: OSN optical observations
  23. GRB 050520: BART optical limit
  24. GRB 050520 - A long GRB detected with INTEGRAL
  25. Swift-BAT trigger 122203 is not a real GRB
  26. GRB 050504: Swift XRT afterglow candidate has faded
  27. XRF 050509c optical afterglow
  28. GRB 050509B and short GRB-SN association? (corrected)
  29. GRB 050509B and short GRB-SN association?
  30. GRB 050509B: Subaru Optical Observations
  31. GRB050502b: Early Observation
  32. GRB050509b, Bok telescope B-band imaging
  33. Refined Chandra analysis of GRB 050509b
  34. GRB050509b, SDSS pre-burst observations
  35. GRB 050509b: Keck/Chandra Cross-Correlation
  36. GRB 050509b: Keck/Chandra Cross-Correlation
  37. Chandra observation of GRB 050509b
  38. GRB 050509b: RAPTOR deep, early limits.
  39. GRB050509B: Optical/Infared observations
  40. GRB 050509b: Swift/UVOT follow-up measurements
  41. GRB 050509b Milagro GeV/TeV Observations
  42. GRB050509B: Optical observations at the Very Large Telescope
  43. GRB 050509b: No Optical Variability in XRT Error Circle
  44. GRB 050509a: Swift-BAT refined analysis
  45. GRB 050509c: ROTSE-III Optical Limits
  46. GRB 050509B: WSRT Radio Observations
  47. GRB050509c: REM NIR and Optical observations (errata corrige to GCN 3400)
  48. GRB 050505, early TAROT observation
  49. GRB050509c (=H3751): An X-Ray Flash Localized By HETE
  50. GRB 050509b: Further Analysis of Keck LRIS Images
  51. GRB050509c: REM NIR and Optical observations
  52. GRB 050509b: Physical Properties of the Candidate Host galaxy
  53. GRB 050505: SARA Observations
  54. Swift UVOT Follow-up Observations of GRB 050509B
  55. GRB 050509B, Optical Observations
  56. GRB 050509B: Swift/XRT refined analysis
  57. GRB 050509b: Optical observations
  58. GRB 050509b: Precision Astrometry
  59. GRB 050509b: Possible Optical Counterpart
  60. Keck/DEIMOS Spectrum of Possible Host Galaxy for GRB050509b
  61. GRB 050509A: Optical observations
  62. GRB 050509b: Optical Counterpart Candidate
  63. GRB 050509b: PAIRITEL and WIYN Observations
  64. GRB 050509b: Swift-BAT refined analysis of the short hard burst
  65. GRB 050509b: optical observations
  66. GRB 050509b: Swift XRT Position
  67. GRB 050509B: ROTSE-III Optical Limits
  68. GRB 050509a: Swift XRT Position
  69. Swift-BAT detection of GRB 050507
  70. GRB 050505: Keck I-band Magnitude
  71. GRB 050505: early time observations
  72. GRB 050505 - Faulkes Telescope North observations
  73. GRB 050502a: Swift XRT Upper Limit
  74. GRB 050505, simultaneous optical observation
  75. GRB 050505: Further Swift UVOT observations.
  76. GRB050505: AAVSO observations
  77. GRB050416A : 1 GHz limit from GMRT
  78. GRB 050505: Keck absorption spectrum and redshift (z=4.27)
  79. GRB 050505 UVOT
  80. GRB050505: Optical Afterglow Candidate
  81. GRB 050505: Swift XRT Position
  82. GRB 050502a: Optical Observations
  83. GRB 050416b:Swift XRT afterglow upper limits
  84. GRB 050416b:Swift XRT afterglow upper limits
  85. GRB 050504: Swift XRT position
  86. GRB050502: P200 Observations (Correction)
  87. GRB050502: P200 Observations
  88. GRB 050504 : R band observation at Lulin observatory
  89. Swift UVOT observation of GRB 050504
  90. GRB 050504, R band Observations
  91. GRB 050502b, V band Observations
  92. GRB050504: P60 Observations
  93. GRB 050504: A long GRB detected with INTEGRAL
  94. GRB (?) 050504: IR Observations, Intriguing Source
  95. GRB 050502b, Optical observations
  96. GRB050502a: P60 Observations (Correction)
  97. GRB050502a: P60 Observations
  98. Renewal of SGR 1806-20 activity
  99. GRB 050502a: RBO Observations
  100. GRB 050502A: WSRT Radio Observations

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