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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').

24546 results found.

  1. GRB 060105: Mitsume optical observations
  2. GRB 060105: BAT refined analysis
  3. GRB 060105: XRT refined analysis
  4. GRB060105: Suzaku-XIS and -HXD observation plan
  5. GRB060105, optical observation
  6. GRB060105: Swift detection of a bright long burst
  7. Swift-BAT trigger 175653 is probably not a GRB
  8. GRB 060102: Swift-BAT refined analysis
  9. GRB 060102: Swift-BAT detection of a burst
  10. GRB 051221B: Optical Observations with Kuiper 1.54m
  11. GRB 051227: Likely host galaxy underlying afterglow position
  12. GRB 051227: optical observation
  13. GRB 051227: optical afterglow
  14. GRB 051227: Magellan r'-band Imaging/Astrometry
  15. GRB 051227: refined analysis of VLT images
  16. GRB 051227: P60 Observations
  17. GRB 051227: MDM Observation
  18. GRB 051227: R-band object in the XRT error circle
  19. GRB 051227: XRT refined analysis
  20. GRB 051227: Further analysis of the Swift-BAT burst
  21. GRB 051227: Refined analysis of the Swift-BAT burst
  22. GRB051227: SDSS pre-burst observations
  23. GRB 051227, optical observation
  24. GRB051117B: optical observation
  25. Konus-Wind observation of GRB 051221A
  26. GRB051221A: Suzaku WAM observation of the prompt emission
  27. GRB 051221A: MDM Optical Observations
  28. GRB051016: analysis of the XMM-Newton observation
  29. GRB 051221A: Refined spectral and temporal analysis of the Swift-BAT short hard burst
  30. GRB 051221B: TAROT optical limits
  31. GRB 051221B: Refined analysis of the Swift-BAT burst
  32. GRB 051221B: BOOTES optical observations.
  33. Swift-BAT detection of a possible burst
  34. GRB 051221: Swift XRT refined analysis
  35. GRB 051221: Swift/UVOT upper limits
  36. GRB 051221: No variability in Gemini data
  37. GRB 051221: Improved astrometry of the IR counterpart
  38. GRB 051221: Refined analysis of the Swift-BAT short hard burst
  39. GRB 051221: Swift detection of a bright short burst
  40. Swift detection of an RS CVn flare star
  41. GRB051211A: possible optical candidate
  42. GRB 051215: near-infrared observations
  43. GRB051215 - SDSS pre-burst observations
  44. GRB 051215: Swift detection of a possible burst
  45. GRB051105: optical observations
  46. GRB 051213: Swift-BAT refined analysis
  47. GRB051211B: XRT refined analysis
  48. GRB 051211B, optical observation
  49. GRB 051211A: Swift/UVOT upper limits
  50. GRB 051211B: Swift/UVOT upper limits
  51. GRB 051211A,optical observation
  52. GRB051211B: Liverpool Telescope observation
  53. GRB051211b: P60 Observations
  54. GRB 051211A and GRB051211B: BOOTES simultaneous observations
  55. GRB 051210: Swift/UVOT upper limits
  56. GRB 051210: Magellan Imaging
  57. GRB 051211: TAROT optical limits
  58. GRB 051211B: a possible optical detection by TAROT
  59. GRB 051211:IAC80 optical observations
  60. GRB 051210: SALT detection limit
  61. GRB 051210: Swift XRT refined analysis
  62. GRB 051210: FRAM early limit
  63. GRB 051210: Swift-BAT refined analysis of a short burst
  64. GRB051210: Swift UVOT Observation
  65. GRB 051210: Swift detection of a burst
  66. An extraordinary long burst on December 3 from SGR1806-20
  67. Possible resuming of the SGR 1806-20 activity
  68. GRB051117B: Swift XRT refined analysis
  69. GRB051117b: No Swift/UVOT Detection
  70. GRB 051117A: Swift/UVOT Detection of an Afterglow: Correction
  71. GRB 051117A: Swift/UVOT Detection of an Afterglow
  72. GRB051111: Suzaku WAM observation of the prompt emission
  73. GRB051008: Suzaku WAM observation of the prompt emission
  74. GRB 051117B: R and I observations of possible host galaxy
  75. GRB 051117A: Refined analysis of the Swift-BAT burst
  76. GRB 051117B: Refined analysis of the Swift-BAT burst
  77. GRB 051117B,optical observation
  78. GRB 051117B: Lulin R and I band observation
  79. GRB051114: results of the Swift-XRT observation
  80. GRB 051109B : Nainital upper limits
  81. GRB 051114: Radio Observations
  82. GRB 051114: Swift-BAT refined analysis
  83. GRB050925: analysis of the XMM-Newton observation
  84. GRB 051114: Swift-BAT detection of a short burst
  85. GRB 051111: Further spectroscopic analysis
  86. GRB 051111: Radio afterglow
  87. GRB 051113: Swift-BAT refined analysis
  88. GRB051103: Radio Observations
  89. GRB/SGR 050925: XMM-Newton ToO observation
  90. GRB051111: Swift/UVOT Observations
  91. GRB051111: XRT preliminary analysis
  92. GRB 051111: Swift-BAT refined analysis
  93. GRB 051109A Optical Observations
  94. GRB 051111A : Lulin BVRI multi band afterglow observation
  95. GRB051111a: SARA Observations
  96. GRB 051111a: IR photometry
  97. GRB 051109B. Radio Observations
  98. GRB 051109A
  99. GRB051109A - radio observations
  100. GRB 051109B: Swift-BAT refined analysis

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