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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"
  1. GRB 050525B: Swift-BAT observations
  2. GRB 050525: MITSuME Optical Observation in VRI
  3. GRB 050525a: MDM Observations
  4. GRB050525A,optical observation
  5. GRB 050525 : Lulin optical afterglow observations
  6. GRB050525: Super-LOTIS observations
  7. GRB 050525, spectral lag pseudo-redshift
  8. GRB 050525a: Gemini/GMOS Spectra
  9. GRB050306: optical afterglow not confirmed
  10. GRB 050525: BART optical observation
  11. GRB 050525A: BOOTES simultaneous optical observations
  12. GRB 050525A: Swift-BAT refined analysis
  13. GRB050525: Optical observations
  14. GRB 050525B: INTEGRAL shows it is unrelated to GRB050525A
  15. GRB 050525: pseudo-redshift
  16. Swift/UVOT UV and optical detections of GRB 050525
  17. Konus-Wind observation of GRB 050525
  18. GRB 050525: TAROT observations of the early afterglow
  19. INTEGRAL detection of GRB 050525
  20. GRB 050525, infrared observations
  21. GRB 050525: Optical observation
  22. GRB 050525: observatons of the optical afterglow
  23. GRB050525: ROTSE-III Refined Analysis
  24. GRB 050525 - Very Bright, Not Short
  25. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  26. GRB 050525A: ROTSE-III Detection of Possible Counterpart
  27. XRF050522: NIR observations of XRT candidate
  28. XRF 050522: Swift XRT refined analysis
  29. XRF050522: Radio Observations
  30. Swift/UVOT observation of XRF 050522
  31. GRB 050509A: Further I-band imaging
  32. GRB050522,optical observation
  33. GRB050520,optical observation
  34. XRF 050522: Continued NIR P200 Monitoring
  35. RBO Observations of GRB050522
  36. GRB050509b: optical observations
  37. Recent GRB BVRcIc field photometry
  38. GRB050520: Radio Observations
  39. XRF 050522: Swift XRT observation
  40. XRF050522, BVRcIc field photometry
  41. XRF 050522 : Lulin observations
  42. XRF050522: Optical Observations
  43. XRF050522: Near-infrared Observations
  44. XRF 050522: KAIT observations
  45. XRF 050522 detected with INTEGRAL
  46. GRB 050520: VLT/ULTRACAM observations
  47. Swift UVOT Observations of GRB 050520
  48. GRB 050520: Swift XRT refined analysis
  49. XRF050509C: Chandra Afterglow Detection
  50. XRF 050509c: Swift XRT Upper Limit
  51. XRF050509c: Radio Observations
  52. RBO Observations of GRB050520
  53. GRB 050520: P200 Observations
  54. GRB050520: Liverpool Telescope follow-up
  55. RBO Observations of GRB050520
  56. GRB 050520: TAROT optical limit
  57. GRB 050520: Swift XRT position
  58. GRB 050520: VLT/ULTRACAM observations
  59. GRB 050520: OSN optical observations
  60. GRB 050520: BART optical limit
  61. GRB 050520 - A long GRB detected with INTEGRAL
  62. No Swift-BAT Lightcurves in real-time for next 3 weeks
  63. Swift-BAT trigger 122203 is not a real GRB
  64. XRF 050509C: REM NIR and Optical refined analysis
  65. GRB 050504: Swift XRT afterglow candidate has faded
  66. XRF 050509c optical afterglow
  67. GRB 050509B and short GRB-SN association? (corrected)
  68. GRB 050509B and short GRB-SN association?
  69. GRB 050509B: Subaru Optical Observations
  70. GRB050502b: Early Observation
  71. GRB050509b, Bok telescope B-band imaging
  72. Refined Chandra analysis of GRB 050509b
  73. GRB050509b, SDSS pre-burst observations
  74. GRB 050509b: Keck/Chandra Cross-Correlation
  75. GRB 050509b: Keck/Chandra Cross-Correlation
  76. Chandra observation of GRB 050509b
  77. GRB 050509b: RAPTOR deep, early limits.
  78. GRB050509B: Optical/Infared observations
  79. GRB 050509b: Swift/UVOT follow-up measurements
  80. GRB 050509b Milagro GeV/TeV Observations
  81. GRB050509B: Optical observations at the Very Large Telescope
  82. GRB 050509b: No Optical Variability in XRT Error Circle
  83. GRB050416: Afterglow detection at 188 nm with Swift UVOT
  84. GRB 050509a: Swift-BAT refined analysis
  85. GRB 050509c: ROTSE-III Optical Limits
  86. GRB 050509B: WSRT Radio Observations
  87. GRB050509c: REM NIR and Optical observations (errata corrige to GCN 3400)
  88. GRB 050505, early TAROT observation
  89. GRB050509c (=H3751): An X-Ray Flash Localized By HETE
  90. GRB 050509b: Further Analysis of Keck LRIS Images
  91. GRB050509c: REM NIR and Optical observations
  92. GRB 050509b: Physical Properties of the Candidate Host galaxy
  93. GRB 050505: SARA Observations
  94. Swift UVOT Follow-up Observations of GRB 050509B
  95. GRB 050509B, Optical Observations
  96. GRB 050509B: Swift/XRT refined analysis
  97. GRB050509a: Swift UVOT observations
  98. GRB 050509b: Optical observations
  99. GRB 050509b: Precision Astrometry
  100. GRB 050509b: Possible Optical Counterpart

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