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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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').

10636 results found.

  1. GRB050803: MASTER further analys
  2. GRB 050803: early Swift XRT analysis results
  3. GCN GRB observation 050713A
  4. GRB050730: FORS1 and UVES/VLT low- and high-resolution spectroscopy
  5. GRB050802: CrAO optical observations
  6. GRB 050802: Swift Gamma-ray Burst
  7. GRB 050801: Swift-BAT refined analysis
  8. GRB 050730, corrected photometry and break?
  9. GRB050730: Refined BAT analysis of the Swift-BAT burst
  10. GRB 050730: Redshift Measurement based on Magellan/MIKE Observations
  11. GRB050730: Liverpool Telescope optical observations
  12. GRB 050730, optical candidate
  13. GRB050730: Swift-BAT detection of a weak burst
  14. GRB050713b: Maidanak optical observations
  15. GRB 050724: Chandra Observations of the X-ray Afterglow
  16. GRB 050724, SMARTS optical/IR afterglow observations
  17. GRB 050726, SMARTS optical/IR observations
  18. GRB 050724: J-band observations
  19. GRB 050724: SWIFT XRT refined position
  20. GRB050721A: Swift-BAT detection of a weak burst
  21. GRB 050712, Tautenburg optical afterglow observations
  22. Konus-Wind observation of GRB 050717
  23. Swift detection of GRB 050717
  24. Konus-Wind observation of GRB 050713A
  25. GRB 050714, R-band candidate
  26. GRB 050714A: ROTSE-III Optical Limits
  27. GRB 050714 - A long GRB detected with INTEGRAL
  28. GRB 050712, optical observations
  29. GRB050709: Candidate X-ray Afterglow from Chandra
  30. GRB 050713: Swift detection of Bright Burst
  31. GRB 050713A: ROTSE-III Optical Limits
  32. GRB050709: Radio Observations
  33. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  34. GRB 050626 optical observations
  35. GRB 050626: Swift XRT observations
  36. GRB 050408: ARC 3.5-meter NIR Observations
  37. GRB050701: Swift-BAT Refined analysis
  38. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  39. GRB 050626 - a long GRB detected with INTEGRAL
  40. H3800 and H3801 on 2005 June 11: two bursts from SGR1806-20 localized by HETE
  41. Konus-Wind observation of an intermediate burst from SGR 1806-20
  42. GRB 050607: Optical decay and spectral slope
  43. Optical Afterglow of GRB 050607
  44. Konus-Wind observation of GRB 050603
  45. GRB050528: updated Liverpool Telescope limits
  46. GRB 050525: RTT150, Optical observations
  47. GRB 050525: MITSuME Optical Observation in VRI
  48. GRB050525: Super-LOTIS observations
  49. GRB 050525A: Swift-BAT refined analysis
  50. GRB050525: Optical observations
  51. Konus-Wind observation of GRB 050525
  52. INTEGRAL detection of GRB 050525
  53. GRB 050525, infrared observations
  54. GRB 050525: Optical observation
  55. GRB050525: ROTSE-III Refined Analysis
  56. GRB 050525: Swift Detection of a Bright, Possibly Short Burst
  57. GRB 050525A: ROTSE-III Detection of Possible Counterpart
  58. XRF050522: NIR observations of XRT candidate
  59. XRF 050522: Swift XRT refined analysis
  60. GRB 050509A: Further I-band imaging
  61. GRB050522,optical observation
  62. GRB050520,optical observation
  63. GRB050509b: optical observations
  64. XRF 050522: Swift XRT observation
  65. XRF050522: Optical Observations
  66. XRF 050522 detected with INTEGRAL
  67. GRB 050520: Swift XRT refined analysis
  68. XRF050509C: Chandra Afterglow Detection
  69. XRF 050509c: Swift XRT Upper Limit
  70. GRB050520: Liverpool Telescope follow-up
  71. GRB 050520 - A long GRB detected with INTEGRAL
  72. Swift-BAT trigger 122203 is not a real GRB
  73. GRB 050509B and short GRB-SN association? (corrected)
  74. GRB 050509B and short GRB-SN association?
  75. GRB050509b, Bok telescope B-band imaging
  76. Chandra observation of GRB 050509b
  77. GRB 050509b: RAPTOR deep, early limits.
  78. GRB 050509a: Swift-BAT refined analysis
  79. GRB 050509c: ROTSE-III Optical Limits
  80. GRB 050509A: Optical observations
  81. GRB 050509b: Swift-BAT refined analysis of the short hard burst
  82. GRB 050509B: ROTSE-III Optical Limits
  83. GRB 050509a: Swift XRT Position
  84. Swift-BAT detection of GRB 050507
  85. GRB 050502a: Swift XRT Upper Limit
  86. GRB050416A : 1 GHz limit from GMRT
  87. GRB050505 Swift-BAT refined analysis
  88. GRB050502b: Afterglow Confirmation: Correction to OT Coordinates
  89. GRB050502b: Afterglow Confirmation
  90. GRB 050504, R band Observations
  91. GRB 050504: A long GRB detected with INTEGRAL
  92. Renewal of SGR 1806-20 activity
  93. GRB050502A: Optical Observations
  94. GRB 050502: INTEGRAL results
  95. GRB 050502 - A long GRB detected with INTEGRAL
  96. GRB 050421: SLOTIS observations
  97. GRB 050421: IR Observations
  98. GRB 050421: ROTSE-III Optical Limits
  99. GRB 050421: NIR observations
  100. Swift Detection of GRB050421

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