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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"

37752 results found.

  1. GRB 050520: BART optical limit
  2. GRB 050520 - A long GRB detected with INTEGRAL
  3. Swift-BAT trigger 122203 is not a real GRB
  4. GRB 050504: Swift XRT afterglow candidate has faded
  5. XRF 050509c optical afterglow
  6. GRB 050509B and short GRB-SN association? (corrected)
  7. GRB 050509B and short GRB-SN association?
  8. GRB 050509B: Subaru Optical Observations
  9. GRB050502b: Early Observation
  10. GRB050509b, Bok telescope B-band imaging
  11. Refined Chandra analysis of GRB 050509b
  12. GRB050509b, SDSS pre-burst observations
  13. GRB 050509b: Keck/Chandra Cross-Correlation
  14. GRB 050509b: Keck/Chandra Cross-Correlation
  15. Chandra observation of GRB 050509b
  16. GRB 050509b: RAPTOR deep, early limits.
  17. GRB050509B: Optical/Infared observations
  18. GRB 050509b: Swift/UVOT follow-up measurements
  19. GRB 050509b Milagro GeV/TeV Observations
  20. GRB050509B: Optical observations at the Very Large Telescope
  21. GRB 050509b: No Optical Variability in XRT Error Circle
  22. GRB 050509a: Swift-BAT refined analysis
  23. GRB 050509c: ROTSE-III Optical Limits
  24. GRB 050509B: WSRT Radio Observations
  25. GRB050509c: REM NIR and Optical observations (errata corrige to GCN 3400)
  26. GRB 050505, early TAROT observation
  27. GRB050509c (=H3751): An X-Ray Flash Localized By HETE
  28. GRB 050509b: Further Analysis of Keck LRIS Images
  29. GRB050509c: REM NIR and Optical observations
  30. GRB 050509b: Physical Properties of the Candidate Host galaxy
  31. GRB 050505: SARA Observations
  32. Swift UVOT Follow-up Observations of GRB 050509B
  33. GRB 050509B, Optical Observations
  34. GRB 050509B: Swift/XRT refined analysis
  35. GRB 050509b: Optical observations
  36. GRB 050509b: Precision Astrometry
  37. GRB 050509b: Possible Optical Counterpart
  38. Keck/DEIMOS Spectrum of Possible Host Galaxy for GRB050509b
  39. GRB 050509A: Optical observations
  40. GRB 050509b: Optical Counterpart Candidate
  41. GRB 050509b: PAIRITEL and WIYN Observations
  42. GRB 050509b: Swift-BAT refined analysis of the short hard burst
  43. GRB 050509b: optical observations
  44. GRB 050509b: Swift XRT Position
  45. GRB 050509B: ROTSE-III Optical Limits
  46. GRB 050509a: Swift XRT Position
  47. Swift-BAT detection of GRB 050507
  48. GRB 050505: Keck I-band Magnitude
  49. GRB 050505: early time observations
  50. GRB 050505 - Faulkes Telescope North observations
  51. GRB 050502a: Swift XRT Upper Limit
  52. GRB 050505, simultaneous optical observation
  53. GRB 050505: Further Swift UVOT observations.
  54. GRB050505: AAVSO observations
  55. GRB050416A : 1 GHz limit from GMRT
  56. GRB 050505: Keck absorption spectrum and redshift (z=4.27)
  57. GRB 050505 UVOT
  58. GRB050505: Optical Afterglow Candidate
  59. GRB 050505: Swift XRT Position
  60. GRB 050502a: Optical Observations
  61. GRB 050416b:Swift XRT afterglow upper limits
  62. GRB 050416b:Swift XRT afterglow upper limits
  63. GRB 050504: Swift XRT position
  64. GRB050502: P200 Observations (Correction)
  65. GRB050502: P200 Observations
  66. GRB 050504 : R band observation at Lulin observatory
  67. Swift UVOT observation of GRB 050504
  68. GRB 050504, R band Observations
  69. GRB 050502b, V band Observations
  70. GRB050504: P60 Observations
  71. GRB 050504: A long GRB detected with INTEGRAL
  72. GRB (?) 050504: IR Observations, Intriguing Source
  73. GRB 050502b, Optical observations
  74. GRB050502a: P60 Observations (Correction)
  75. GRB050502a: P60 Observations
  76. Renewal of SGR 1806-20 activity
  77. GRB 050502a: RBO Observations
  78. GRB 050502A: WSRT Radio Observations
  79. GRB050502A: Optical Observations
  80. Swift UVOT refined analysis
  81. Retraction of Swift-BAT trigger 116145
  82. GRB 050502a : R band observation at Lulin observatory
  83. GRB 050502b : optical observation at Lulin observatory
  84. GRB 050502b: Swift XRT Position
  85. GRB 050502A: Redshift measurement based on Keck HIRES Observations
  86. GRB 050502: INTEGRAL results
  87. GRB050502: ANU 1m optical Observations
  88. GRB 050502: Confirmed variability of the afterglow candidate +
  89. GRB 050502: PAIRITEL IR Observations
  90. GRB050502 - Correction on the Optical Candidate from the Liverpool
  91. GRB 050502 - A long GRB detected with INTEGRAL
  92. GRB 050502: ROTSE-III Detection of Possible Counterpart
  93. Swift-BAT Trigger 115881 is not a real GRB
  94. Swift/BAT possible detection of a weak burst GRB050430
  95. GRB 050401: Rc observation
  96. GRB050416a: Radio Detection
  97. GRB 050422: Swift-UVOT observation
  98. GRB 050422: Swift-BAT refined analysis
  99. GRB 050422: Swift XRT Position
  100. Swift Detection of GRB 050422

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