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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').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

18406 results found.

  1. GRB 060313: Swift-XRT team refined analysis
  2. GRB 060313: Refined analysis of the Swift-BAT bright short hard burst
  3. GRB 060313: Swift XRT position
  4. GRB060313: optical and near infrared observations with REM
  5. GRB 060313: Swift-BAT detection of a bright short hard burst
  6. GRB060312: Swift UVOT observation
  7. GRB 060312: Refined analysis of the Swift-BAT burst
  8. GRB 060312: Swift XRT team refined analysis
  9. GRB060306: APO Ks-band Imaging Observations
  10. GRB 060312: ROTSE-III Optical Limits
  11. GRB 060312: Swift detection of a burst
  12. Bright short hard GRB 060303: IPN localization and Konus spectrum
  13. GRB060218: analysis of the XMM-Newton observation
  14. Swift/UVOT observations of GRB060306
  15. GRB 060306: Swift-BAT refined analysis
  16. GRB 060306: Swift-XRT team refined analysis
  17. GRB 060306: Swift detection of a bright burst
  18. GRB060218: Ep,i - Eiso correlation
  19. GRB 060223b: Swift/UVOT Upper Limits
  20. GRB 060223B: Swift XRT possible afterglow
  21. GRB 060223B: Swift-BAT refined analysis
  22. GRB 060223a: Swift/UVOT refined analysis
  23. GRB 060223: Swift XRT Team preliminary analysis
  24. GRB 060218/SN 2006aj: Swift-BAT fluence and peak flux
  25. GRB 060223B: Swift detection of a bright burst
  26. GRB 060223: Swift-BAT refined analysis
  27. GRB 060223: Swift/UVOT Confirmation of Optical Afterglow
  28. GRB 060223: Swift detection of a burst
  29. GRB 060219: Swift-BAT refined analysis
  30. GRB 060218: Further refined analysis of the Swift-BAT burst
  31. GRB 060218: Likely an underluminous GRB
  32. GRB 060219: SDSS galaxy inside XRT error circle
  33. GRB060218: UV Detection and Light Curves
  34. GRB 060219: Swift/UVOT Upper Limits
  35. GRB 060219: Swift-XRT Team refined analysis
  36. GRB 051221B: Swift-XRT Team Refined Analysis
  37. GRB 060219: Partial refined analysis of the Swift-BAT burst
  38. GRB 060219: Swift-XRT position typo correction
  39. GRB 060219: Swift-XRT position
  40. GRB 060218: optical/nIR observations at La Palma
  41. GRB 060219: Swift-BAT detection of a weak burst
  42. Oddball GRB 060218, transient or GRB?
  43. GRB060218: Swift/XRT Team preliminary analysis of the possible burst
  44. Brightening of the Optical Counterpart of the Possible GRB 060218
  45. GRB 060218: MDM Observations
  46. GRB 060218A: ROTSE-III Possible Optical Flare
  47. GRB060218: Swift/XRT refined position of a possible burst
  48. Preliminary refined analysis of the Swift-BAT trigger 191157
  49. Further UVOT Observations of the Candidate Optical Afterglow for GRB 060218
  50. GRB 060211B: Swift/UVOT Upper Limits
  51. GRB 060218: Swift XRT Position
  52. GRB 060218: Swift-BAT detection of a possible burst
  53. GRB 060213: optical afterglow not confirmed
  54. Swift UVOT observations of GRB060213
  55. GRB060213: Swift XRT observations and possible afterglow candidate
  56. GRB 060211b: WIRO NIR Observations
  57. GRB060206: Swift XRT observations of an unbroken powerlaw decay
  58. GRB 060213: IPN localization
  59. GRB 060211a: WIRO NIR Observations
  60. GRB 060211B: BAT detects no additional burst emission beyond T + 122 sec
  61. GRB 060211A: Further refined analysis of the Swift burst
  62. GRB 060210: ARC NIR Detection of Afterglow and Possible Host Galaxy
  63. GRB 060211A: Partial refined analysis on the Swift-BAT burst
  64. GRB 050826: Optical Afterglow and Host Galaxy
  65. GRB 060210: Further refined analysis of the Swift-BAT burst
  66. GRB 060211B: Swift/BAT refined analysis
  67. GRB060210: Swift/UVOT Upper Limits
  68. GRB 060211B: Swift-XRT Team refined analysis
  69. GRB060211B: Swift/XRT position
  70. GRB 060210: Optical Observations
  71. GRB 060211A: Swift XRT Team Refined Analysis
  72. GRB 060211B: Swift-BAT detection of a burst
  73. GRB060211: Faulkes North observation
  74. GRB 060211: Swift detection of a long burst
  75. GRB 060210: Refined analysis of the Swift-BAT burst
  76. GRB060210: Swift XRT Refined Analysis
  77. GRB060210: Early Optical Observations
  78. GRB060210:Faulkes Telescope North Afterglow Confirmation
  79. GRB 060210: candidate afterglow
  80. GRB 060210: Swift detection of a burst
  81. GRB060210: Optical afterglow
  82. GRB 060206: Swift/UVOT Observations
  83. Swift-BAT trigger 180931 is not a GRB
  84. GRB060209: RTT150 optical observations
  85. GRB 060209 : TAROT optical observation
  86. GRB 060209(?): Swift-BAT detection of a possible burst
  87. GRB 060206: WSRT Radio Observations
  88. GRB 060203: Swift/UVOT upper limits
  89. GRB060204a: Swift XRT Source is not GRB Afterglow
  90. GRB 060204b: pseudo-z from spectral parameters of the prompt emission
  91. GRB 060204A: ROSAT Pointing
  92. GRB060204A: Swift/UVOT observations
  93. GRB 060206: Swift-BAT refined analysis
  94. GRB060206: Swift XRT Refined Analysis
  95. GRB060206: Swift XRT Position
  96. GRB060204a: Swift XRT Detection of an Afterglow Candidate
  97. GRB060206 - Swift UVOT Confirmation of Optical Afterglow
  98. GRB060206: Swift-BAT detection of a burst
  99. GRB 060204C: XRT analysis of Swift J061223.0+701243.9
  100. BAT GRB 060204C is probably not a GRB

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