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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"

28091 results found.

  1. GRB 051021B: Refined analysis of the Swift-BAT burst
  2. GRB 051022: SSO40 Optical Observations
  3. GRB051022,optical observation
  4. GRB 051021,optical observation
  5. GRB 051021B: Swift detection of a burst
  6. GRB 051021 : optical afterglow observation at Lulin
  7. GRB 051021: Optical observations and candidate afterglow
  8. GRB051021.63
  9. GRB051021.6: MASTER optical observation
  10. GRB051021: A GRB Localized by HETE
  11. Swift-BAT triggered on a posible CR Shower or possible GRB
  12. GRB 051016b: Optical limit
  13. Afterglow candidate of GRB 051016B observed at Lulin
  14. GRB 051016A: Swift/UVOT upper limits
  15. GRB 051016B: refined analysis of the Swift/XRT data
  16. GRB 051016B: Swift/UVOT detection
  17. GRB 051016B,optical observation
  18. GRB 051016B : Optical follow-up at Lulin
  19. GRB 051016B: Refined analysis of the Swift-BAT burst
  20. GRB 051016B: Swift detection of a soft burst
  21. GRB 051016: Swift-BAT refined analysis
  22. GRB051016 XMM-Newton observation
  23. GRB051016: Swift XRT refined analysis.
  24. GRB 051016: PROMPT Observations
  25. GRB051016: Swift detection of a burst
  26. Photometric calibration of Swift/UVOT and Re-analysis of Swift/UVOT GRB 050922C data
  27. GRB 051012: Swift-BAT detection of burst yesterday
  28. Swift-BAT Trigger 159578 is a possible burst
  29. GRB 051006: Swift/UVOT Upper Limits
  30. GRB051008: optical candidate
  31. GRB 051008 - a low redshift low-luminosity burst?
  32. GRB051011: bright nebulae near error box
  33. GRB051011: MASTER optical observation
  34. GRB051008: Final refined analysis of the Swift-BAT burst
  35. GRB051008: Radio Observation
  36. GRB 051008, optical observations
  37. GRB 051008: early Swift XRT analysis
  38. GRB 051008: Swift UVOT Candidate
  39. GRB 051006: P60 Observations
  40. Swift-BAT trigger 158700 is a probable Cosmic Ray Shower Event
  41. GRB 051006: optical observations at Sierra Nevada
  42. GRB051006: Refined analysis of the Swift-BAT burst
  43. GRB051006: Swift detection of a burst
  44. GRB 050906, summary of radio observations
  45. GRB051001: Swift UVOT Upper Limits
  46. GRB 050925: Second Epoch WSRT Radio Observations
  47. GRB 051001: I-band limit
  48. GRB 051001: AAT infra-red observations
  49. GRB 051001: Swift-BAT refined analysis
  50. GRB 051001: Swift Detection of a Burst
  51. GRB 050820A: NIR photometry at the TNG
  52. GRB050925: Swift/XRT limits
  53. GRB/SGR 050925: IR Observations
  54. GRB 050922C: break in the lightcurve
  55. GRB050925: Swift UVOT upper limits
  56. Refined analysis of the Swift-BAT soft short burst
  57. GRB050925: Faulkes Telescope North R-band limit
  58. GRB050925: Swift-BAT detection of a short burst
  59. GRB050922C: TNG spectroscopic observations
  60. GRB050922B: refined XRT analysis
  61. GRB050922B: Swift UVOT early upper limits.
  62. GRB050922C: Optical Observations
  63. GRB 050922C: Swift XRT refined analysis
  64. HETE Fregate observations of GRB 050922C
  65. GRB 050922C: Swift-BAT refined analysis
  66. GRB 050922B: Swift-BAT refined analysis
  67. GRB 050922C: optical obserations
  68. GRB 050922C: NOT optical observations
  69. GRB 050922C: Swift detection of a bright burst
  70. GRB 050922B: ROTSE-III Optical Limits
  71. GRB 050922B,optical observation
  72. GRB050922B: Swift-BAT detection of a weak long burst
  73. GRB050820B: analysis of the XMM-Newton observation
  74. GRB050916: Swift/UVOT Upper Limits
  75. GRB 050916: Swift-BAT refined analysis
  76. Swift-BAT trigger 155764 is not a GRB
  77. Swift-BAT trigger 155764 is probably not a GRB
  78. Swift trigger 155764: bad XRT centroid
  79. Swift-BAT trigger 155535 is definitely not a GRB
  80. GRB050916 : Swift-XRT refined analysis
  81. GRB 050915B: Swift-BAT refined analysis
  82. GRB 050915B: Swift/UVOT Upper Limits
  83. GRB 050915a: IR Transient
  84. GRB 050915b, SMARTS optical/IR observations
  85. GRB050915B: Swift-BAT detection of a long bright burst
  86. GRB050915: Swift/UVOT upper limits
  87. GRB 050915: IR Observations
  88. GRB 050915: Swift XRT refined analysis
  89. GRB 050915: Swift-BAT refined analysis
  90. GRB 050915: Swift detection of a GRB
  91. GRB050911: Upper limit on X-ray afterglow
  92. Swift-BAT trigger 155072 ground analysis
  93. Swift-BAT trigger 155072 is probably not a GRB
  94. GRB 050908: DEIMOS spectrum and further analysis
  95. GRB 050911, optical content of Swift/XRT error box
  96. GRB 050911: Swift-BAT refined analysis
  97. GRB 050911: z~0.16 cluster in the field
  98. GRB050911: Swift-BAT detection of a long burst
  99. GRB 050910a: TAROT early optical limits
  100. WIRO observations in I of GRB 050908

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