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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"

24887 results found.

  1. GRB 051021B: Swift detection of a burst
  2. GRB 051021 : optical afterglow observation at Lulin
  3. GRB 051021: Optical observations and candidate afterglow
  4. GRB051021.63
  5. GRB051021.6: MASTER optical observation
  6. GRB051021: A GRB Localized by HETE
  7. Swift-BAT triggered on a posible CR Shower or possible GRB
  8. GRB 051016b: Optical limit
  9. Afterglow candidate of GRB 051016B observed at Lulin
  10. GRB 051016A: Swift/UVOT upper limits
  11. GRB 051016B: refined analysis of the Swift/XRT data
  12. GRB 051016B: Swift/UVOT detection
  13. GRB 051016B,optical observation
  14. GRB 051016B : Optical follow-up at Lulin
  15. GRB 051016B: Refined analysis of the Swift-BAT burst
  16. GRB 051016B: Swift detection of a soft burst
  17. GRB 051016: Swift-BAT refined analysis
  18. GRB051016 XMM-Newton observation
  19. GRB051016: Swift XRT refined analysis.
  20. GRB 051016: PROMPT Observations
  21. GRB051016: Swift detection of a burst
  22. Photometric calibration of Swift/UVOT and Re-analysis of Swift/UVOT GRB 050922C data
  23. GRB 051012: Swift-BAT detection of burst yesterday
  24. Swift-BAT Trigger 159578 is a possible burst
  25. GRB 051006: Swift/UVOT Upper Limits
  26. GRB051008: optical candidate
  27. GRB 051008 - a low redshift low-luminosity burst?
  28. GRB051011: bright nebulae near error box
  29. GRB051011: MASTER optical observation
  30. GRB051008: Final refined analysis of the Swift-BAT burst
  31. GRB051008: Radio Observation
  32. GRB 051008, optical observations
  33. GRB 051008: early Swift XRT analysis
  34. GRB 051008: Swift UVOT Candidate
  35. GRB 051006: P60 Observations
  36. Swift-BAT trigger 158700 is a probable Cosmic Ray Shower Event
  37. GRB 051006: optical observations at Sierra Nevada
  38. GRB051006: Refined analysis of the Swift-BAT burst
  39. GRB051006: Swift detection of a burst
  40. GRB 050906, summary of radio observations
  41. GRB051001: Swift UVOT Upper Limits
  42. GRB 050925: Second Epoch WSRT Radio Observations
  43. GRB 051001: I-band limit
  44. GRB 051001: AAT infra-red observations
  45. GRB 051001: Swift-BAT refined analysis
  46. GRB 051001: Swift Detection of a Burst
  47. GRB 050820A: NIR photometry at the TNG
  48. GRB050925: Swift/XRT limits
  49. GRB/SGR 050925: IR Observations
  50. GRB 050922C: break in the lightcurve
  51. GRB050925: Swift UVOT upper limits
  52. Refined analysis of the Swift-BAT soft short burst
  53. GRB050925: Faulkes Telescope North R-band limit
  54. GRB050925: Swift-BAT detection of a short burst
  55. GRB050922C: TNG spectroscopic observations
  56. GRB050922B: refined XRT analysis
  57. GRB050922B: Swift UVOT early upper limits.
  58. GRB050922C: Optical Observations
  59. GRB 050922C: Swift XRT refined analysis
  60. HETE Fregate observations of GRB 050922C
  61. GRB 050922C: Swift-BAT refined analysis
  62. GRB 050922B: Swift-BAT refined analysis
  63. GRB 050922C: optical obserations
  64. GRB 050922C: NOT optical observations
  65. GRB 050922C: Swift detection of a bright burst
  66. GRB 050922B: ROTSE-III Optical Limits
  67. GRB 050922B,optical observation
  68. GRB050922B: Swift-BAT detection of a weak long burst
  69. GRB050820B: analysis of the XMM-Newton observation
  70. GRB050916: Swift/UVOT Upper Limits
  71. GRB 050916: Swift-BAT refined analysis
  72. Swift-BAT trigger 155764 is not a GRB
  73. Swift-BAT trigger 155764 is probably not a GRB
  74. Swift trigger 155764: bad XRT centroid
  75. Swift-BAT trigger 155535 is definitely not a GRB
  76. GRB050916 : Swift-XRT refined analysis
  77. GRB 050915B: Swift-BAT refined analysis
  78. GRB 050915B: Swift/UVOT Upper Limits
  79. GRB 050915a: IR Transient
  80. GRB 050915b, SMARTS optical/IR observations
  81. GRB050915B: Swift-BAT detection of a long bright burst
  82. GRB050915: Swift/UVOT upper limits
  83. GRB 050915: IR Observations
  84. GRB 050915: Swift XRT refined analysis
  85. GRB 050915: Swift-BAT refined analysis
  86. GRB 050915: Swift detection of a GRB
  87. GRB050911: Upper limit on X-ray afterglow
  88. Swift-BAT trigger 155072 ground analysis
  89. Swift-BAT trigger 155072 is probably not a GRB
  90. GRB 050908: DEIMOS spectrum and further analysis
  91. GRB 050911, optical content of Swift/XRT error box
  92. GRB 050911: Swift-BAT refined analysis
  93. GRB 050911: z~0.16 cluster in the field
  94. GRB050911: Swift-BAT detection of a long burst
  95. GRB 050910a: TAROT early optical limits
  96. WIRO observations in I of GRB 050908
  97. GRB 050906: Possible X-ray Counterpart
  98. GRB050908: Swift/UVOT Early upper limits
  99. GRB050908 : Swift-XRT refined analysis
  100. GRB 050908: Swift-BAT refined analysis

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