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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').

18318 results found.

  1. GRB 060323: Swift/XRT position
  2. GRB 060322: Refined analysis of the Swift-BAT burst
  3. GRB060323 - SDSS Pre-Burst Observations
  4. GRB 060323: Swift detection of a burst with a possible optical afterglow
  5. GRB 060322: Swift-BAT detection of a 200-sec burst
  6. GRB 060319: IAC-80 optical observations
  7. GRB060319: Swift XRT refined analysis
  8. GRB060319: Swift/UVOT upper limits
  9. GRB 060319: Swift-BAT refined analysis
  10. GRB060319: Swift/XRT position
  11. GRB 060319: Swift detection of a burst
  12. Konus-Wind observation of GRB 060313
  13. GRB 060313: Further analysis of the Swift-BAT bright short hard burst
  14. GRB 060313: Swift/UVOT Observations
  15. GRB 060313: Swift-XRT team refined analysis
  16. GRB 060313: Refined analysis of the Swift-BAT bright short hard burst
  17. GRB 060313: Swift XRT position
  18. GRB060313: optical and near infrared observations with REM
  19. GRB 060313: Swift-BAT detection of a bright short hard burst
  20. GRB060312: Swift UVOT observation
  21. GRB 060312: Refined analysis of the Swift-BAT burst
  22. GRB 060312: Swift XRT team refined analysis
  23. GRB060306: APO Ks-band Imaging Observations
  24. GRB 060312: ROTSE-III Optical Limits
  25. GRB 060312: Swift detection of a burst
  26. Bright short hard GRB 060303: IPN localization and Konus spectrum
  27. GRB060218: analysis of the XMM-Newton observation
  28. Swift/UVOT observations of GRB060306
  29. GRB 060306: Swift-BAT refined analysis
  30. GRB 060306: Swift-XRT team refined analysis
  31. GRB 060306: Swift detection of a bright burst
  32. GRB060218: Ep,i - Eiso correlation
  33. GRB 060223b: Swift/UVOT Upper Limits
  34. GRB 060223B: Swift XRT possible afterglow
  35. GRB 060223B: Swift-BAT refined analysis
  36. GRB 060223a: Swift/UVOT refined analysis
  37. GRB 060223: Swift XRT Team preliminary analysis
  38. GRB 060218/SN 2006aj: Swift-BAT fluence and peak flux
  39. GRB 060223B: Swift detection of a bright burst
  40. GRB 060223: Swift-BAT refined analysis
  41. GRB 060223: Swift/UVOT Confirmation of Optical Afterglow
  42. GRB 060223: Swift detection of a burst
  43. GRB 060219: Swift-BAT refined analysis
  44. GRB 060218: Further refined analysis of the Swift-BAT burst
  45. GRB 060218: Likely an underluminous GRB
  46. GRB 060219: SDSS galaxy inside XRT error circle
  47. GRB060218: UV Detection and Light Curves
  48. GRB 060219: Swift/UVOT Upper Limits
  49. GRB 060219: Swift-XRT Team refined analysis
  50. GRB 051221B: Swift-XRT Team Refined Analysis
  51. GRB 060219: Partial refined analysis of the Swift-BAT burst
  52. GRB 060219: Swift-XRT position typo correction
  53. GRB 060219: Swift-XRT position
  54. GRB 060218: optical/nIR observations at La Palma
  55. GRB 060219: Swift-BAT detection of a weak burst
  56. Oddball GRB 060218, transient or GRB?
  57. GRB060218: Swift/XRT Team preliminary analysis of the possible burst
  58. Brightening of the Optical Counterpart of the Possible GRB 060218
  59. GRB 060218: MDM Observations
  60. GRB 060218A: ROTSE-III Possible Optical Flare
  61. GRB060218: Swift/XRT refined position of a possible burst
  62. Preliminary refined analysis of the Swift-BAT trigger 191157
  63. Further UVOT Observations of the Candidate Optical Afterglow for GRB 060218
  64. GRB 060211B: Swift/UVOT Upper Limits
  65. GRB 060218: Swift XRT Position
  66. GRB 060218: Swift-BAT detection of a possible burst
  67. GRB 060213: optical afterglow not confirmed
  68. Swift UVOT observations of GRB060213
  69. GRB060213: Swift XRT observations and possible afterglow candidate
  70. GRB 060211b: WIRO NIR Observations
  71. GRB060206: Swift XRT observations of an unbroken powerlaw decay
  72. GRB 060213: IPN localization
  73. GRB 060211a: WIRO NIR Observations
  74. GRB 060211B: BAT detects no additional burst emission beyond T + 122 sec
  75. GRB 060211A: Further refined analysis of the Swift burst
  76. GRB 060210: ARC NIR Detection of Afterglow and Possible Host Galaxy
  77. GRB 060211A: Partial refined analysis on the Swift-BAT burst
  78. GRB 050826: Optical Afterglow and Host Galaxy
  79. GRB 060210: Further refined analysis of the Swift-BAT burst
  80. GRB 060211B: Swift/BAT refined analysis
  81. GRB060210: Swift/UVOT Upper Limits
  82. GRB 060211B: Swift-XRT Team refined analysis
  83. GRB060211B: Swift/XRT position
  84. GRB 060210: Optical Observations
  85. GRB 060211A: Swift XRT Team Refined Analysis
  86. GRB 060211B: Swift-BAT detection of a burst
  87. GRB060211: Faulkes North observation
  88. GRB 060211: Swift detection of a long burst
  89. GRB 060210: Refined analysis of the Swift-BAT burst
  90. GRB060210: Swift XRT Refined Analysis
  91. GRB060210: Early Optical Observations
  92. GRB060210:Faulkes Telescope North Afterglow Confirmation
  93. GRB 060210: candidate afterglow
  94. GRB 060210: Swift detection of a burst
  95. GRB060210: Optical afterglow
  96. GRB 060206: Swift/UVOT Observations
  97. Swift-BAT trigger 180931 is not a GRB
  98. GRB060209: RTT150 optical observations
  99. GRB 060209 : TAROT optical observation
  100. GRB 060209(?): Swift-BAT detection of a possible burst

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