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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. GRB050326: analysis of the XMM-Newton observation
  2. GRB 050412: Chandra observations
  3. Swift-BAT detection of the bright and long GRB 050418
  4. GRB 050416B: optical observations
  5. GRB 050416: Swift-BAT refined analysis
  6. GRB 050416: Radio observations
  7. GRB 050408: RTT150 optical observations
  8. GRB050408: optical observation
  9. GRB 050412 : XingLong optical observation
  10. GRB050412: optical limit before and during GRB
  11. GRB050412: ROTSE-III Optical Limits
  12. GRB 050410, optical observations
  13. GRB 050410, optical observations
  14. GRB 050408: Swift XRT measurement of possible jet break
  15. Swift-BAT detection of GRB 050410
  16. GRB 050410: Swift XRT Position
  17. GRB 050408: Optical limit at 20 min after the burst
  18. GRB 050408, optical observations
  19. GRB 050408,optical observation
  20. GRB 050408: Mercator Optical Observations
  21. GRB 050408, optical observations
  22. GRB 050408: ROTSE-III Optical Limits
  23. Konus-Wind observation of GRB 050401
  24. GRB 050401 BAT refined analysis
  25. Swift Trigger 113225: P60 Observations
  26. GRB050401: ROTSE-III Detection of Prompt Optical Counterpart
  27. Swift-BAT detection of GRB 050401
  28. GRB 050401: Prompt XRT position
  29. GRB050331: No Afterglow Detected
  30. Swift-BAT detection of GRB 050331
  31. Konus-Wind observation of GRB 050326
  32. GRB050326: optical limit 33min before GRB
  33. GRB050319, optical observations
  34. GRB050319: optical observation, March 20-22
  35. Swift-BAT detection of a bright outburst from SGR1806-20
  36. GRB 050319: Absorption redshift from the Nordic Optical Telescope
  37. GRB 050319: ROTSE-III Refined Analysis
  38. Refined Swift XRT positions for GRB050315, GRB050318 and GRB050319
  39. GRB 050319: NIR afterglow candidate
  40. GRB 050319:Near IR afterglow
  41. GRB050319: BR optical photometry
  42. GRB 050319: Optical observation
  43. GRB050223: analysis of the XMM-Newton observation
  44. GRB050315: Radio afterglow
  45. GRB 050315: Absorption redshift
  46. GRB 050315: Optical afterglow identification
  47. GRB 050315: Swift XRT Position
  48. Swift-BAT detection of GRB 050315
  49. Swift-BAT trigger 107873 (GRB050309): possible X-ray counterparts
  50. GRB 050306: R-band observations
  51. Swift trigger 107518: optical observation
  52. Ongoing activity of SGR 1806-20 after the giant flare
  53. GRB050215B: Late-Time Swift UVOT Observations
  54. INTEGRAL detection of GRB 050223
  55. GRB 050223 : Planned XMM-Newton observation
  56. GRB050223: ROTSE-III Optical Observations
  57. GRB 050219a: Optical observations from LCO
  58. GRB 050215b: Swift XRT Source Variability
  59. GRB 050215b : Lulin follow-up observation
  60. GRB050215B: ROTSE-III optical observations
  61. GRB050215A: ROTSE-III Optical Observations
  62. short/hard GRB 050202, optical observations
  63. GRB 050129: a weak long GRB detected with INTEGRAL
  64. SGR1806-20: Swift-BAT detection of a large normal burst
  65. SGR 1806-20: GMRT results at 240 MHz band.
  66. SGR 1806-20: low frequency GMRT results of 2005 Jan 16.
  67. GRB 050128: Swift XRT prompt afterglow position
  68. GRB050126: Burst Parameters Measured by BAT
  69. GRB 050124 : Lulin R-band follow-up observation
  70. GRB050124: Refined BAT position, spectral and fluence information
  71. Unusual optical transient (GRB ???)
  72. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  73. GRB050117b: Swift-BAT detection of a weak burst
  74. GRB050117: optical observation
  75. GRB050117: Refined XRT position
  76. GRB050117: MASTER optical observations
  77. MASTER:GRB050117 SWIFT
  78. SGR 1806-20: RXTE/PCA pulse frequency during flare
  79. Triangulation of Short Hard GRB050112 (large error box)
  80. SGR 1806-20: Further VLA Observations
  81. SGR 1806-20: Further low frequency GMRT results
  82. SGR 1806-20: Further VLA Observations
  83. SGR1806-20: Swift-BAT observations of two additional bursts
  84. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  85. Further VLA observations of SGR 1806-20
  86. SGR 1806-20 and extragalactic short-duration GRBs
  87. Further ATCA observations of SGR 1806-20
  88. Fourth Epoch VLA observations of SGR 1806-20
  89. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  90. SGR 1806-20: Temporal and Spectral behavior of radio transient
  91. ATCA observations of SGR 1806-20
  92. SGR 1806-20, RHESSI observations of the 041227 giant flare
  93. Third epoch observations of SGR 1806-20 with VLA
  94. Second Epoch VLA observations of SGR 1806-20
  95. Second-epoch VLA observations of SGR 1806-20
  96. SGR1806: Detection of a Sudden Ionospheric Disturbance
  97. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  98. VLA observations of SGR 1806-20
  99. SGR1806 VLA Observations
  100. VLA observations of SGR 1806-20

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