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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.

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

35947 results found.

  1. GRB 051021, SMARTS optical/IR observations
  2. GRB 051021: P200 Ks Observations
  3. IPN triangulation of GRB051022 (=H3950)
  4. GRB 051021: MDM Upper Limit
  5. GRB 051022 (=H3950): SXC Flight Localization is Valid
  6. GRB051021: Swift/UVOT Upper Limits
  7. GRB 051021B: Refined analysis of the Swift-BAT burst
  8. GRB 051022: SSO40 Optical Observations
  9. GRB 051022A: ROTSE-III Optical Limits
  10. GRB051022 (=H3590), A GRB Detected By HETE
  11. GRB 051022: Optical observations
  12. GRB 051021,optical observation
  13. GRB051021B: Swift XRT Position
  14. GRB 051021: SOAR NIR Observations
  15. GRB 051021B: Swift detection of a burst
  16. GRB051021 (=H3947): Refined Analysis
  17. GRB 051021 : optical afterglow observation at Lulin
  18. GRB 051021: Optical observations
  19. GRB 051021: ROTSE-III Confirmation of Optical Counterpart
  20. GRB 051021: Optical observations and candidate afterglow
  21. GRB051021.63
  22. GRB051021.6: MASTER optical observation
  23. Swift-BAT trigger 160640 is not a real GRB
  24. GRB051021: A GRB Localized by HETE
  25. Swift-BAT trigger 160619 is not a GRB
  26. Swift-BAT triggered on a posible CR Shower or possible GRB
  27. GRB 050502b: Optical limit
  28. GRB 051016b: Optical limit
  29. Afterglow candidate of GRB 051016B observed at Lulin
  30. GRB 051016b: Gemini Near IR Observations
  31. GRB 051016A: Swift/UVOT upper limits
  32. GRB 051016B: refined analysis of the Swift/XRT data
  33. GRB 051016B: Swift/UVOT detection
  34. GRB 051016B,optical observation
  35. GRB 051016B : Optical follow-up at Lulin
  36. GRB 051016B: Refined analysis of the Swift-BAT burst
  37. GRB 051016B: Swift detection of a soft burst
  38. GRB 051016: Swift-BAT refined analysis
  39. GRB051016: Swift XRT refined analysis.
  40. GRB 051016: LCO optical and near-IR imaging
  41. GRB 051016: PROMPT Observations
  42. GRB051016: Swift detection of a burst
  43. Photometric calibration of Swift/UVOT and Re-analysis of Swift/UVOT GRB 050922C data
  44. GRB051006: optical observations
  45. GRB 051012: Swift-BAT detection of burst yesterday
  46. Swift trigger 159578 is not a burst
  47. GRB 051006: Swift/UVOT Upper Limits
  48. IBAS Alert 2675 : not a GRB
  49. GRB051008: optical candidate
  50. GRB 051008: - a high redshift high-luminosity burst?
  51. GRB 051008 - a low redshift low-luminosity burst?
  52. IBAS Alert 2673: not a real GRB
  53. GRB051011: MASTER optical observation
  54. GRB051008: optical observation
  55. GRB051008: Swift XRT refined analysis
  56. GRB051008 - Swift UVOT upper limits
  57. Konus-Wind observation of GRB 051008
  58. GRB051008: Final refined analysis of the Swift-BAT burst
  59. GRB 051008: R-band upper limit
  60. GRB051008: Radio Observation
  61. GRB 051008: Swift XRT position
  62. GRB 051008, optical observations
  63. GRB 051008: early Swift XRT analysis
  64. GRB 051008: Swift UVOT Candidate
  65. GRB 051006: P60 Observations
  66. grb test
  67. GRB 051006: XRT refined analysis
  68. GRB 051006: optical observations at Sierra Nevada
  69. GRB 051006: XRT position
  70. GRB 050906, summary of radio observations
  71. GRB 050925: Second Epoch WSRT Radio Observations
  72. GRB 051001: Swift XRT refined analysis
  73. GRB 051001, optical observations at Mt. John
  74. GRB 051001: I-band limit
  75. GRB 051001: AAT infra-red observations
  76. GRB 051001: Swift-BAT refined analysis
  77. GRB 051001: Swift Detection of a Burst
  78. GRB 051001: ROTSE-III Optical Limits
  79. GRB050908: optical observations
  80. GRB050922C: optical observation
  81. GRB050922B: optical limit
  82. GRB 050922C: further VLT observations
  83. GRB 050820A: NIR photometry at the TNG
  84. GRB050922C: UVES/VLT high resolution spectroscopy
  85. GRB050925: Swift/XRT limits
  86. GRB/SGR 050925: IR Observations
  87. GRB 050922C: break in the lightcurve
  88. GRB 050925: WSRT Radio Observations
  89. GRB 050925 : I-band observation at Xinglong observatory
  90. GRB050925: Faulkes Telescope North R-band limit
  91. GRB050925: Swift-BAT detection of a short burst
  92. GRB 050922B: Correction to BAT refined analysis, longer burst
  93. GRB050922C: TNG spectroscopic observations
  94. GRB050922B: refined XRT analysis
  95. Konus-Wind observation of GRB 050922C
  96. GRB 050922C: Refined redshift
  97. GRB OT observation
  98. GRB050922C: observation at MonteBoo
  99. INT 2.5m limit for GRB050922B
  100. GRB 050922B: optical limit

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