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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"

45709 results found.

  1. Swift/UVOT observation of XRF 050522
  2. GRB 050509A: Further I-band imaging
  3. GRB050522,optical observation
  4. GRB050520,optical observation
  5. XRF 050522: Continued NIR P200 Monitoring
  6. RBO Observations of GRB050522
  7. GRB050509b: optical observations
  8. Recent GRB BVRcIc field photometry
  9. GRB050520: Radio Observations
  10. XRF 050522: Swift XRT observation
  11. XRF050522, BVRcIc field photometry
  12. XRF 050522 : Lulin observations
  13. XRF050522: Optical Observations
  14. XRF050522: Near-infrared Observations
  15. XRF 050522: KAIT observations
  16. XRF 050522 detected with INTEGRAL
  17. GRB 050520: VLT/ULTRACAM observations
  18. Swift UVOT Observations of GRB 050520
  19. GRB 050520: Swift XRT refined analysis
  20. XRF050509C: Chandra Afterglow Detection
  21. XRF 050509c: Swift XRT Upper Limit
  22. XRF050509c: Radio Observations
  23. RBO Observations of GRB050520
  24. GRB 050520: P200 Observations
  25. GRB050520: Liverpool Telescope follow-up
  26. RBO Observations of GRB050520
  27. GRB 050520: TAROT optical limit
  28. GRB 050520: Swift XRT position
  29. GRB 050520: VLT/ULTRACAM observations
  30. GRB 050520: OSN optical observations
  31. GRB 050520: BART optical limit
  32. GRB 050520 - A long GRB detected with INTEGRAL
  33. No Swift-BAT Lightcurves in real-time for next 3 weeks
  34. Swift-BAT trigger 122203 is not a real GRB
  35. XRF 050509C: REM NIR and Optical refined analysis
  36. GRB 050504: Swift XRT afterglow candidate has faded
  37. XRF 050509c optical afterglow
  38. GRB 050509B and short GRB-SN association? (corrected)
  39. GRB 050509B and short GRB-SN association?
  40. GRB 050509B: Subaru Optical Observations
  41. GRB050502b: Early Observation
  42. GRB050509b, Bok telescope B-band imaging
  43. Refined Chandra analysis of GRB 050509b
  44. GRB050509b, SDSS pre-burst observations
  45. GRB 050509b: Keck/Chandra Cross-Correlation
  46. GRB 050509b: Keck/Chandra Cross-Correlation
  47. Chandra observation of GRB 050509b
  48. GRB 050509b: RAPTOR deep, early limits.
  49. GRB050509B: Optical/Infared observations
  50. GRB 050509b: Swift/UVOT follow-up measurements
  51. GRB 050509b Milagro GeV/TeV Observations
  52. GRB050509B: Optical observations at the Very Large Telescope
  53. GRB 050509b: No Optical Variability in XRT Error Circle
  54. GRB050416: Afterglow detection at 188 nm with Swift UVOT
  55. GRB 050509a: Swift-BAT refined analysis
  56. GRB 050509c: ROTSE-III Optical Limits
  57. GRB 050509B: WSRT Radio Observations
  58. GRB050509c: REM NIR and Optical observations (errata corrige to GCN 3400)
  59. GRB 050505, early TAROT observation
  60. GRB050509c (=H3751): An X-Ray Flash Localized By HETE
  61. GRB 050509b: Further Analysis of Keck LRIS Images
  62. GRB050509c: REM NIR and Optical observations
  63. GRB 050509b: Physical Properties of the Candidate Host galaxy
  64. GRB 050505: SARA Observations
  65. Swift UVOT Follow-up Observations of GRB 050509B
  66. GRB 050509B, Optical Observations
  67. GRB 050509B: Swift/XRT refined analysis
  68. GRB050509a: Swift UVOT observations
  69. GRB 050509b: Optical observations
  70. GRB 050509b: Precision Astrometry
  71. GRB 050509b: Possible Optical Counterpart
  72. Keck/DEIMOS Spectrum of Possible Host Galaxy for GRB050509b
  73. GRB 050509A: Optical observations
  74. GRB 050509b: Optical Counterpart Candidate
  75. GRB050509b: Radio Observations
  76. GRB 050509b: PAIRITEL and WIYN Observations
  77. GRB 050509b: Swift-BAT refined analysis of the short hard burst
  78. GRB 050509b: optical observations
  79. GRB 050509b: Swift XRT Position
  80. GRB 050509B: ROTSE-III Optical Limits
  81. Swift Detection of GRB050509b: A short duration burst
  82. GRB 050509a: Swift XRT Position
  83. Swift Detection of the Burst GRB050509
  84. Swift-BAT detection of GRB 050507
  85. GRB 050505: Keck I-band Magnitude
  86. GRB 050505: early time observations
  87. GRB 050505 - Faulkes Telescope North observations
  88. GRB 050502a: Swift XRT Upper Limit
  89. GRB 050505, simultaneous optical observation
  90. GRB050505: Infrared observations
  91. GRB 050505: Further Swift UVOT observations.
  92. GRB050505: AAVSO observations
  93. GRB050416A : 1 GHz limit from GMRT
  94. GRB 050505: Keck absorption spectrum and redshift (z=4.27)
  95. GRB 050505 UVOT
  96. GRB050505: Optical Afterglow Candidate
  97. GRB 050505: Swift XRT Position
  98. GRB050505 Swift-BAT refined analysis
  99. GRB 050502a: Optical Observations
  100. GRB 050416b:Swift XRT afterglow upper limits

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