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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"

37750 results found.

  1. Swift-BAT trigger 122203 is not a real GRB
  2. GRB 050504: Swift XRT afterglow candidate has faded
  3. XRF 050509c optical afterglow
  4. GRB 050509B and short GRB-SN association? (corrected)
  5. GRB 050509B and short GRB-SN association?
  6. GRB 050509B: Subaru Optical Observations
  7. GRB050502b: Early Observation
  8. GRB050509b, Bok telescope B-band imaging
  9. Refined Chandra analysis of GRB 050509b
  10. GRB050509b, SDSS pre-burst observations
  11. GRB 050509b: Keck/Chandra Cross-Correlation
  12. GRB 050509b: Keck/Chandra Cross-Correlation
  13. Chandra observation of GRB 050509b
  14. GRB 050509b: RAPTOR deep, early limits.
  15. GRB050509B: Optical/Infared observations
  16. GRB 050509b: Swift/UVOT follow-up measurements
  17. GRB 050509b Milagro GeV/TeV Observations
  18. GRB050509B: Optical observations at the Very Large Telescope
  19. GRB 050509b: No Optical Variability in XRT Error Circle
  20. GRB 050509a: Swift-BAT refined analysis
  21. GRB 050509c: ROTSE-III Optical Limits
  22. GRB 050509B: WSRT Radio Observations
  23. GRB050509c: REM NIR and Optical observations (errata corrige to GCN 3400)
  24. GRB 050505, early TAROT observation
  25. GRB050509c (=H3751): An X-Ray Flash Localized By HETE
  26. GRB 050509b: Further Analysis of Keck LRIS Images
  27. GRB050509c: REM NIR and Optical observations
  28. GRB 050509b: Physical Properties of the Candidate Host galaxy
  29. GRB 050505: SARA Observations
  30. Swift UVOT Follow-up Observations of GRB 050509B
  31. GRB 050509B, Optical Observations
  32. GRB 050509B: Swift/XRT refined analysis
  33. GRB 050509b: Optical observations
  34. GRB 050509b: Precision Astrometry
  35. GRB 050509b: Possible Optical Counterpart
  36. Keck/DEIMOS Spectrum of Possible Host Galaxy for GRB050509b
  37. GRB 050509A: Optical observations
  38. GRB 050509b: Optical Counterpart Candidate
  39. GRB 050509b: PAIRITEL and WIYN Observations
  40. GRB 050509b: Swift-BAT refined analysis of the short hard burst
  41. GRB 050509b: optical observations
  42. GRB 050509b: Swift XRT Position
  43. GRB 050509B: ROTSE-III Optical Limits
  44. GRB 050509a: Swift XRT Position
  45. Swift-BAT detection of GRB 050507
  46. GRB 050505: Keck I-band Magnitude
  47. GRB 050505: early time observations
  48. GRB 050505 - Faulkes Telescope North observations
  49. GRB 050502a: Swift XRT Upper Limit
  50. GRB 050505, simultaneous optical observation
  51. GRB 050505: Further Swift UVOT observations.
  52. GRB050505: AAVSO observations
  53. GRB050416A : 1 GHz limit from GMRT
  54. GRB 050505: Keck absorption spectrum and redshift (z=4.27)
  55. GRB 050505 UVOT
  56. GRB050505: Optical Afterglow Candidate
  57. GRB 050505: Swift XRT Position
  58. GRB 050502a: Optical Observations
  59. GRB 050416b:Swift XRT afterglow upper limits
  60. GRB 050416b:Swift XRT afterglow upper limits
  61. GRB 050504: Swift XRT position
  62. GRB050502: P200 Observations (Correction)
  63. GRB050502: P200 Observations
  64. GRB 050504 : R band observation at Lulin observatory
  65. Swift UVOT observation of GRB 050504
  66. GRB 050504, R band Observations
  67. GRB 050502b, V band Observations
  68. GRB050504: P60 Observations
  69. GRB 050504: A long GRB detected with INTEGRAL
  70. GRB (?) 050504: IR Observations, Intriguing Source
  71. GRB 050502b, Optical observations
  72. GRB050502a: P60 Observations (Correction)
  73. GRB050502a: P60 Observations
  74. Renewal of SGR 1806-20 activity
  75. GRB 050502a: RBO Observations
  76. GRB 050502A: WSRT Radio Observations
  77. GRB050502A: Optical Observations
  78. Swift UVOT refined analysis
  79. Retraction of Swift-BAT trigger 116145
  80. GRB 050502a : R band observation at Lulin observatory
  81. GRB 050502b : optical observation at Lulin observatory
  82. GRB 050502b: Swift XRT Position
  83. GRB 050502A: Redshift measurement based on Keck HIRES Observations
  84. GRB 050502: INTEGRAL results
  85. GRB050502: ANU 1m optical Observations
  86. GRB 050502: Confirmed variability of the afterglow candidate +
  87. GRB 050502: PAIRITEL IR Observations
  88. GRB050502 - Correction on the Optical Candidate from the Liverpool
  89. GRB 050502 - A long GRB detected with INTEGRAL
  90. GRB 050502: ROTSE-III Detection of Possible Counterpart
  91. Swift-BAT Trigger 115881 is not a real GRB
  92. Swift/BAT possible detection of a weak burst GRB050430
  93. GRB 050401: Rc observation
  94. GRB050416a: Radio Detection
  95. GRB 050422: Swift-UVOT observation
  96. GRB 050422: Swift-BAT refined analysis
  97. GRB 050422: Swift XRT Position
  98. Swift Detection of GRB 050422
  99. GRB 050421: NIR observations
  100. GRB 050416: Optical/NIR observations

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