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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"

37768 results found.

  1. Recent GRB BVRcIc field photometry
  2. GRB050520: Radio Observations
  3. XRF050522, BVRcIc field photometry
  4. XRF050522: Optical Observations
  5. XRF 050522: KAIT observations
  6. XRF 050522 detected with INTEGRAL
  7. GRB 050520: VLT/ULTRACAM observations
  8. Swift UVOT Observations of GRB 050520
  9. GRB 050520: Swift XRT refined analysis
  10. RBO Observations of GRB050520
  11. GRB 050520: P200 Observations
  12. GRB050520: Liverpool Telescope follow-up
  13. GRB 050520: TAROT optical limit
  14. GRB 050520: Swift XRT position
  15. GRB 050520: VLT/ULTRACAM observations
  16. GRB 050520: OSN optical observations
  17. GRB 050520: BART optical limit
  18. GRB 050520 - A long GRB detected with INTEGRAL
  19. Swift-BAT trigger 122203 is not a real GRB
  20. GRB 050504: Swift XRT afterglow candidate has faded
  21. XRF 050509c optical afterglow
  22. GRB 050509B and short GRB-SN association? (corrected)
  23. GRB 050509B and short GRB-SN association?
  24. GRB 050509B: Subaru Optical Observations
  25. GRB050502b: Early Observation
  26. GRB050509b, Bok telescope B-band imaging
  27. Refined Chandra analysis of GRB 050509b
  28. GRB050509b, SDSS pre-burst observations
  29. GRB 050509b: Keck/Chandra Cross-Correlation
  30. GRB 050509b: Keck/Chandra Cross-Correlation
  31. Chandra observation of GRB 050509b
  32. GRB 050509b: RAPTOR deep, early limits.
  33. GRB050509B: Optical/Infared observations
  34. GRB 050509b: Swift/UVOT follow-up measurements
  35. GRB 050509b Milagro GeV/TeV Observations
  36. GRB050509B: Optical observations at the Very Large Telescope
  37. GRB 050509b: No Optical Variability in XRT Error Circle
  38. GRB 050509a: Swift-BAT refined analysis
  39. GRB 050509c: ROTSE-III Optical Limits
  40. GRB 050509B: WSRT Radio Observations
  41. GRB050509c: REM NIR and Optical observations (errata corrige to GCN 3400)
  42. GRB 050505, early TAROT observation
  43. GRB050509c (=H3751): An X-Ray Flash Localized By HETE
  44. GRB 050509b: Further Analysis of Keck LRIS Images
  45. GRB050509c: REM NIR and Optical observations
  46. GRB 050509b: Physical Properties of the Candidate Host galaxy
  47. GRB 050505: SARA Observations
  48. Swift UVOT Follow-up Observations of GRB 050509B
  49. GRB 050509B, Optical Observations
  50. GRB 050509B: Swift/XRT refined analysis
  51. GRB 050509b: Optical observations
  52. GRB 050509b: Precision Astrometry
  53. GRB 050509b: Possible Optical Counterpart
  54. Keck/DEIMOS Spectrum of Possible Host Galaxy for GRB050509b
  55. GRB 050509A: Optical observations
  56. GRB 050509b: Optical Counterpart Candidate
  57. GRB 050509b: PAIRITEL and WIYN Observations
  58. GRB 050509b: Swift-BAT refined analysis of the short hard burst
  59. GRB 050509b: optical observations
  60. GRB 050509b: Swift XRT Position
  61. GRB 050509B: ROTSE-III Optical Limits
  62. GRB 050509a: Swift XRT Position
  63. Swift-BAT detection of GRB 050507
  64. GRB 050505: Keck I-band Magnitude
  65. GRB 050505: early time observations
  66. GRB 050505 - Faulkes Telescope North observations
  67. GRB 050502a: Swift XRT Upper Limit
  68. GRB 050505, simultaneous optical observation
  69. GRB 050505: Further Swift UVOT observations.
  70. GRB050505: AAVSO observations
  71. GRB050416A : 1 GHz limit from GMRT
  72. GRB 050505: Keck absorption spectrum and redshift (z=4.27)
  73. GRB 050505 UVOT
  74. GRB050505: Optical Afterglow Candidate
  75. GRB 050505: Swift XRT Position
  76. GRB 050502a: Optical Observations
  77. GRB 050416b:Swift XRT afterglow upper limits
  78. GRB 050416b:Swift XRT afterglow upper limits
  79. GRB 050504: Swift XRT position
  80. GRB050502: P200 Observations (Correction)
  81. GRB050502: P200 Observations
  82. GRB 050504 : R band observation at Lulin observatory
  83. Swift UVOT observation of GRB 050504
  84. GRB 050504, R band Observations
  85. GRB 050502b, V band Observations
  86. GRB050504: P60 Observations
  87. GRB 050504: A long GRB detected with INTEGRAL
  88. GRB (?) 050504: IR Observations, Intriguing Source
  89. GRB 050502b, Optical observations
  90. GRB050502a: P60 Observations (Correction)
  91. GRB050502a: P60 Observations
  92. Renewal of SGR 1806-20 activity
  93. GRB 050502a: RBO Observations
  94. GRB 050502A: WSRT Radio Observations
  95. GRB050502A: Optical Observations
  96. Swift UVOT refined analysis
  97. Retraction of Swift-BAT trigger 116145
  98. GRB 050502a : R band observation at Lulin observatory
  99. GRB 050502b : optical observation at Lulin observatory
  100. GRB 050502b: Swift XRT Position

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