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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').

17828 results found.

  1. SGR 1900+14: CORRECTION to GCN 4923
  2. SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
  3. SGR 1900+14: Swift detection of renewed activity
  4. GRB060323: NOT optical observations
  5. GRB 060322: IAC80 optical observations
  6. GRB 060322: Swift XRT afterglow candidate
  7. GRB 060323: Swift/UVOT Observations
  8. GRB060323: NOT observations
  9. GRB 060323: Refined analysis of the Swift-BAT burst
  10. GRB 060323: Swift XRT refined analysis
  11. GRB 060323: Swift/XRT position
  12. GRB 060322: Refined analysis of the Swift-BAT burst
  13. GRB060323 - SDSS Pre-Burst Observations
  14. GRB 060323: Swift detection of a burst with a possible optical afterglow
  15. GRB 060322: Swift-BAT detection of a 200-sec burst
  16. GRB 060319: IAC-80 optical observations
  17. GRB060319: Swift XRT refined analysis
  18. GRB060319: Swift/UVOT upper limits
  19. GRB 060319: Swift-BAT refined analysis
  20. GRB060319: Swift/XRT position
  21. GRB 060319: Swift detection of a burst
  22. Konus-Wind observation of GRB 060313
  23. GRB 060313: Further analysis of the Swift-BAT bright short hard burst
  24. GRB 060313: Swift/UVOT Observations
  25. GRB 060313: Swift-XRT team refined analysis
  26. GRB 060313: Refined analysis of the Swift-BAT bright short hard burst
  27. GRB 060313: Swift XRT position
  28. GRB060313: optical and near infrared observations with REM
  29. GRB 060313: Swift-BAT detection of a bright short hard burst
  30. GRB060312: Swift UVOT observation
  31. GRB 060312: Refined analysis of the Swift-BAT burst
  32. GRB 060312: Swift XRT team refined analysis
  33. GRB060306: APO Ks-band Imaging Observations
  34. GRB 060312: ROTSE-III Optical Limits
  35. GRB 060312: Swift detection of a burst
  36. Bright short hard GRB 060303: IPN localization and Konus spectrum
  37. GRB060218: analysis of the XMM-Newton observation
  38. Swift/UVOT observations of GRB060306
  39. GRB 060306: Swift-BAT refined analysis
  40. GRB 060306: Swift-XRT team refined analysis
  41. GRB 060306: Swift detection of a bright burst
  42. GRB060218: Ep,i - Eiso correlation
  43. GRB 060223b: Swift/UVOT Upper Limits
  44. GRB 060223B: Swift XRT possible afterglow
  45. GRB 060223B: Swift-BAT refined analysis
  46. GRB 060223a: Swift/UVOT refined analysis
  47. GRB 060223: Swift XRT Team preliminary analysis
  48. GRB 060218/SN 2006aj: Swift-BAT fluence and peak flux
  49. GRB 060223B: Swift detection of a bright burst
  50. GRB 060223: Swift-BAT refined analysis
  51. GRB 060223: Swift/UVOT Confirmation of Optical Afterglow
  52. GRB 060223: Swift detection of a burst
  53. GRB 060219: Swift-BAT refined analysis
  54. GRB 060218: Further refined analysis of the Swift-BAT burst
  55. GRB 060218: Likely an underluminous GRB
  56. GRB 060219: SDSS galaxy inside XRT error circle
  57. GRB060218: UV Detection and Light Curves
  58. GRB 060219: Swift/UVOT Upper Limits
  59. GRB 060219: Swift-XRT Team refined analysis
  60. GRB 051221B: Swift-XRT Team Refined Analysis
  61. GRB 060219: Partial refined analysis of the Swift-BAT burst
  62. GRB 060219: Swift-XRT position typo correction
  63. GRB 060219: Swift-XRT position
  64. GRB 060218: optical/nIR observations at La Palma
  65. GRB 060219: Swift-BAT detection of a weak burst
  66. Oddball GRB 060218, transient or GRB?
  67. GRB060218: Swift/XRT Team preliminary analysis of the possible burst
  68. Brightening of the Optical Counterpart of the Possible GRB 060218
  69. GRB 060218: MDM Observations
  70. GRB 060218A: ROTSE-III Possible Optical Flare
  71. GRB060218: Swift/XRT refined position of a possible burst
  72. Preliminary refined analysis of the Swift-BAT trigger 191157
  73. Further UVOT Observations of the Candidate Optical Afterglow for GRB 060218
  74. GRB 060211B: Swift/UVOT Upper Limits
  75. Subject: GRB 060218: Swift XRT Position
  76. GRB 060218: Swift-BAT detection of a possible burst
  77. GRB 060213: optical afterglow not confirmed
  78. Swift UVOT observations of GRB060213
  79. GRB060213: Swift XRT observations and possible afterglow candidate
  80. GRB 060211b: WIRO NIR Observations
  81. GRB060206: Swift XRT observations of an unbroken powerlaw decay
  82. GRB 060213: IPN localization
  83. GRB 060211a: WIRO NIR Observations
  84. GRB 060211B: BAT detects no additional burst emission beyond T + 122 sec
  85. GRB 060211A: Further refined analysis of the Swift burst
  86. GRB 060210: ARC NIR Detection of Afterglow and Possible Host Galaxy
  87. GRB 060211A: Partial refined analysis on the Swift-BAT burst
  88. GRB 050826: Optical Afterglow and Host Galaxy
  89. GRB 060210: Further refined analysis of the Swift-BAT burst
  90. GRB 060211B: Swift/BAT refined analysis
  91. GRB060210: Swift/UVOT Upper Limits
  92. GRB 060211B: Swift-XRT Team refined analysis
  93. GRB060211B: Swift/XRT position
  94. GRB 060210: Optical Observations
  95. GRB 060211A: Swift XRT Team Refined Analysis
  96. GRB 060211B: Swift-BAT detection of a burst
  97. GRB060211: Faulkes North observation
  98. GRB 060211: Swift detection of a long burst
  99. GRB 060210: Refined analysis of the Swift-BAT burst
  100. GRB060210: Swift XRT Refined Analysis

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