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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"

43594 results found.

  1. GRB 051016: PROMPT Observations
  2. GRB051016: Swift detection of a burst
  3. Photometric calibration of Swift/UVOT and Re-analysis of Swift/UVOT GRB 050922C data
  4. GRB 051012: Swift-BAT detection of burst yesterday
  5. Swift trigger 159578 is not a burst
  6. Swift-BAT Trigger 159578 is a possible burst
  7. GRB050805A: Rc optical observations
  8. GRB 051006: Swift/UVOT Upper Limits
  9. IBAS Alert 2675 : not a GRB
  10. GRB051008: optical candidate
  11. GRB 051008: - a high redshift high-luminosity burst?
  12. GRB 051008 - a low redshift low-luminosity burst?
  13. IBAS Alert 2673: not a real GRB
  14. GRB051011: bright nebulae near error box
  15. GRB051008: Swift XRT refined analysis
  16. GRB051008 - Swift UVOT upper limits
  17. Konus-Wind observation of GRB 051008
  18. GRB051008: Final refined analysis of the Swift-BAT burst
  19. GRB051008: Refined analysis of the Swift-BAT burst
  20. GRB051008: Radio Observation
  21. GRB 051008: Swift XRT position
  22. GRB 051008, optical observations
  23. GRB 051008: early Swift XRT analysis
  24. GRB 051008: Swift UVOT Candidate
  25. GRB051008: Swift-BAT detection of a bright burst
  26. GRB 051006: P60 Observations
  27. grb test
  28. GRB 051006: XRT refined analysis
  29. Swift-BAT trigger 158700 is a probable Cosmic Ray Shower Event
  30. GRB 051006: optical observations at Sierra Nevada
  31. GRB051006: Refined analysis of the Swift-BAT burst
  32. GRB 051006: XRT position
  33. GRB051006: Swift detection of a burst
  34. GRB 050906, summary of radio observations
  35. Swift-BAT triggers 158261 and 158262 Retraction
  36. GRB051001: Swift UVOT Upper Limits
  37. GRB 050925: Second Epoch WSRT Radio Observations
  38. GRB 051001: Swift XRT refined analysis
  39. GRB 051001, optical observations at Mt. John
  40. GRB 051001: I-band limit
  41. GRB 051001: AAT infra-red observations
  42. GRB 051001: Swift-BAT refined analysis
  43. GRB 051001: Swift Detection of a Burst
  44. GRB 051001: ROTSE-III Optical Limits
  45. GRB050908: optical observations
  46. GRB050922C: optical observation
  47. GRB050922B: optical limit
  48. GRB 050922C: further VLT observations
  49. GRB 050820A: NIR photometry at the TNG
  50. GRB050922C: UVES/VLT high resolution spectroscopy
  51. GRB050925: Swift/XRT limits
  52. GRB/SGR 050925: IR Observations
  53. GRB050922C - Swift UVOT preliminary analysis
  54. GRB 050922C: break in the lightcurve
  55. GRB 050925: WSRT Radio Observations
  56. GRB050925: Swift UVOT upper limits
  57. Refined analysis of the Swift-BAT soft short burst
  58. GRB050925: Faulkes Telescope North R-band limit
  59. GRB050925: Swift-BAT detection of a short burst
  60. GRB 050922B: Correction to BAT refined analysis, longer burst
  61. GRB050922C: TNG spectroscopic observations
  62. GRB050922B: refined XRT analysis
  63. Konus-Wind observation of GRB 050922C
  64. GRB 050922C: Refined redshift
  65. GRB050922B: Swift UVOT early upper limits.
  66. INT 2.5m limit for GRB050922B
  67. GRB050922C: Optical Observations
  68. GRB 050922C: Swift XRT refined analysis
  69. HETE Fregate observations of GRB 050922C
  70. GRB 050922C: Swift-BAT refined analysis
  71. GRB 050922B: Swift-BAT refined analysis
  72. GRB050922C: optical observations
  73. GRB 050922C: Absorption redshift from the Nordic Optical Telescope
  74. GRB 050922C: optical obserations
  75. GRB 050922C: NOT optical observations
  76. GRB 050922A: Analysis of Swift/XRT TOO observation
  77. GRB 050922C: Swift detection of a bright burst
  78. GRB 050922C: ROTSE-IIId Refined Analysis
  79. GRB 050922C: ROTSE-III Detection of Possible Counterpart
  80. GRB 050922B: ROTSE-III Optical Limits
  81. GRB 050922B,optical observation
  82. GRB050922B: Swift-BAT detection of a weak long burst
  83. Possible GRB 050922 detected by INTEGRAL
  84. GRB050918: Possible Swift/XRT detected afterglow
  85. GRB050820B: analysis of the XMM-Newton observation
  86. GRB050916: Swift/UVOT Upper Limits
  87. GRB 050916: Swift-BAT refined analysis
  88. GRB 050918 - A long GRB detected by INTEGRAL
  89. GRB 050915a: Radio Observations
  90. Swift-BAT trigger 155764 is not a GRB
  91. Swift-BAT trigger 155764 is probably not a GRB
  92. Swift trigger 155764: bad XRT centroid
  93. Swift-BAT trigger 155535 is definitely not a GRB
  94. GRB050916 : Swift-XRT refined analysis
  95. GRB 050916: XRT position
  96. GRB 050915b, SMARTS optical/IR observations of the XRT position
  97. GRB 050915B: Swift-BAT refined analysis
  98. GRB 050915B: Swift/UVOT Upper Limits
  99. GRB050916: Swift-BAT detection of a long weak burst
  100. GRB 050915a: IR Transient

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