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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"

37945 results found.

  1. XRF050522: Radio Observations
  2. Swift/UVOT observation of XRF 050522
  3. GRB 050509A: Further I-band imaging
  4. GRB050522,optical observation
  5. GRB050520,optical observation
  6. XRF 050522: Continued NIR P200 Monitoring
  7. RBO Observations of GRB050522
  8. GRB050509b: optical observations
  9. Recent GRB BVRcIc field photometry
  10. GRB050520: Radio Observations
  11. XRF 050522: Swift XRT observation
  12. XRF050522, BVRcIc field photometry
  13. XRF050522: Optical Observations
  14. XRF 050522: KAIT observations
  15. XRF 050522 detected with INTEGRAL
  16. GRB 050520: VLT/ULTRACAM observations
  17. Swift UVOT Observations of GRB 050520
  18. GRB 050520: Swift XRT refined analysis
  19. XRF050509C: Chandra Afterglow Detection
  20. XRF 050509c: Swift XRT Upper Limit
  21. RBO Observations of GRB050520
  22. GRB 050520: P200 Observations
  23. GRB050520: Liverpool Telescope follow-up
  24. GRB 050520: TAROT optical limit
  25. GRB 050520: Swift XRT position
  26. GRB 050520: VLT/ULTRACAM observations
  27. GRB 050520: OSN optical observations
  28. GRB 050520: BART optical limit
  29. GRB 050520 - A long GRB detected with INTEGRAL
  30. No Swift-BAT Lightcurves in real-time for next 3 weeks
  31. Swift-BAT trigger 122203 is not a real GRB
  32. GRB 050504: Swift XRT afterglow candidate has faded
  33. XRF 050509c optical afterglow
  34. GRB 050509B and short GRB-SN association? (corrected)
  35. GRB 050509B and short GRB-SN association?
  36. GRB 050509B: Subaru Optical Observations
  37. GRB050502b: Early Observation
  38. GRB050509b, Bok telescope B-band imaging
  39. Refined Chandra analysis of GRB 050509b
  40. GRB050509b, SDSS pre-burst observations
  41. GRB 050509b: Keck/Chandra Cross-Correlation
  42. GRB 050509b: Keck/Chandra Cross-Correlation
  43. Chandra observation of GRB 050509b
  44. GRB 050509b: RAPTOR deep, early limits.
  45. GRB050509B: Optical/Infared observations
  46. GRB 050509b: Swift/UVOT follow-up measurements
  47. GRB 050509b Milagro GeV/TeV Observations
  48. GRB050509B: Optical observations at the Very Large Telescope
  49. GRB 050509b: No Optical Variability in XRT Error Circle
  50. GRB050416: Afterglow detection at 188 nm with Swift UVOT
  51. GRB 050509a: Swift-BAT refined analysis
  52. GRB 050509c: ROTSE-III Optical Limits
  53. GRB 050509B: WSRT Radio Observations
  54. GRB050509c: REM NIR and Optical observations (errata corrige to GCN 3400)
  55. GRB 050505, early TAROT observation
  56. GRB050509c (=H3751): An X-Ray Flash Localized By HETE
  57. GRB 050509b: Further Analysis of Keck LRIS Images
  58. GRB050509c: REM NIR and Optical observations
  59. GRB 050509b: Physical Properties of the Candidate Host galaxy
  60. GRB 050505: SARA Observations
  61. Swift UVOT Follow-up Observations of GRB 050509B
  62. GRB 050509B, Optical Observations
  63. GRB 050509B: Swift/XRT refined analysis
  64. GRB050509a: Swift UVOT observations
  65. GRB 050509b: Optical observations
  66. GRB 050509b: Precision Astrometry
  67. GRB 050509b: Possible Optical Counterpart
  68. Keck/DEIMOS Spectrum of Possible Host Galaxy for GRB050509b
  69. GRB 050509A: Optical observations
  70. GRB 050509b: Optical Counterpart Candidate
  71. GRB 050509b: PAIRITEL and WIYN Observations
  72. GRB 050509b: Swift-BAT refined analysis of the short hard burst
  73. GRB 050509b: optical observations
  74. GRB 050509b: Swift XRT Position
  75. GRB 050509B: ROTSE-III Optical Limits
  76. Swift Detection of GRB050509b: A short duration burst
  77. GRB 050509a: Swift XRT Position
  78. Swift Detection of the Burst GRB050509
  79. Swift-BAT detection of GRB 050507
  80. GRB 050505: Keck I-band Magnitude
  81. GRB 050505: early time observations
  82. GRB 050505 - Faulkes Telescope North observations
  83. GRB 050502a: Swift XRT Upper Limit
  84. GRB 050505, simultaneous optical observation
  85. GRB 050505: Further Swift UVOT observations.
  86. GRB050505: AAVSO observations
  87. GRB050416A : 1 GHz limit from GMRT
  88. GRB 050505: Keck absorption spectrum and redshift (z=4.27)
  89. GRB 050505 UVOT
  90. GRB050505: Optical Afterglow Candidate
  91. GRB 050505: Swift XRT Position
  92. GRB050505 Swift-BAT refined analysis
  93. GRB 050502a: Optical Observations
  94. GRB 050416b:Swift XRT afterglow upper limits
  95. GRB 050416b:Swift XRT afterglow upper limits
  96. Swift-BAT detection of GRB050505
  97. GRB 050504: Swift XRT position
  98. GRB050502: P200 Observations (Correction)
  99. GRB050502: P200 Observations
  100. GRB 050504 : R band observation at Lulin observatory

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