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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').
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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"

35958 results found.

  1. GRB 051022: Swift/UVOT Upper Limits
  2. GRB051022: Radio Counterpart
  3. GRB 051022: SOAR JKs Observations
  4. Konus-Wind observation of GRB 051022
  5. GRB051022: Optical Observations
  6. GRB 051022: Magellan NIR imaging
  7. GRB 051021: PROMPT RcIc Observations
  8. GRB051021b: Magellan IR Imaging
  9. GRB 051022: Spectral Analysis Indicates That The Spectrum Is Absorbed
  10. GRB 051021: Correction
  11. GRB 051022, J & K-band observation
  12. GRB 051021, SMARTS optical/IR observations
  13. GRB 051021: P200 Ks Observations
  14. IPN triangulation of GRB051022 (=H3950)
  15. GRB 051021: MDM Upper Limit
  16. GRB 051022 (=H3950): SXC Flight Localization is Valid
  17. GRB051021: Swift/UVOT Upper Limits
  18. GRB 051021B: Refined analysis of the Swift-BAT burst
  19. GRB 051022: SSO40 Optical Observations
  20. GRB 051022A: ROTSE-III Optical Limits
  21. GRB051022 (=H3590), A GRB Detected By HETE
  22. GRB 051022: Optical observations
  23. GRB 051021,optical observation
  24. GRB051021B: Swift XRT Position
  25. GRB 051021: SOAR NIR Observations
  26. GRB 051021B: Swift detection of a burst
  27. GRB051021 (=H3947): Refined Analysis
  28. GRB 051021 : optical afterglow observation at Lulin
  29. GRB 051021: Optical observations
  30. GRB 051021: ROTSE-III Confirmation of Optical Counterpart
  31. GRB 051021: Optical observations and candidate afterglow
  32. GRB051021.63
  33. GRB051021.6: MASTER optical observation
  34. Swift-BAT trigger 160640 is not a real GRB
  35. GRB051021: A GRB Localized by HETE
  36. Swift-BAT trigger 160619 is not a GRB
  37. Swift-BAT triggered on a posible CR Shower or possible GRB
  38. GRB 050502b: Optical limit
  39. GRB 051016b: Optical limit
  40. Afterglow candidate of GRB 051016B observed at Lulin
  41. GRB 051016b: Gemini Near IR Observations
  42. GRB 051016A: Swift/UVOT upper limits
  43. GRB 051016B: refined analysis of the Swift/XRT data
  44. GRB 051016B: Swift/UVOT detection
  45. GRB 051016B,optical observation
  46. GRB 051016B : Optical follow-up at Lulin
  47. GRB 051016B: Refined analysis of the Swift-BAT burst
  48. GRB 051016B: Swift detection of a soft burst
  49. GRB 051016: Swift-BAT refined analysis
  50. GRB051016: Swift XRT refined analysis.
  51. GRB 051016: LCO optical and near-IR imaging
  52. GRB 051016: PROMPT Observations
  53. GRB051016: Swift detection of a burst
  54. Photometric calibration of Swift/UVOT and Re-analysis of Swift/UVOT GRB 050922C data
  55. GRB051006: optical observations
  56. GRB 051012: Swift-BAT detection of burst yesterday
  57. Swift trigger 159578 is not a burst
  58. GRB 051006: Swift/UVOT Upper Limits
  59. IBAS Alert 2675 : not a GRB
  60. GRB051008: optical candidate
  61. GRB 051008: - a high redshift high-luminosity burst?
  62. GRB 051008 - a low redshift low-luminosity burst?
  63. IBAS Alert 2673: not a real GRB
  64. GRB051011: MASTER optical observation
  65. GRB051008: optical observation
  66. GRB051008: Swift XRT refined analysis
  67. GRB051008 - Swift UVOT upper limits
  68. Konus-Wind observation of GRB 051008
  69. GRB051008: Final refined analysis of the Swift-BAT burst
  70. GRB 051008: R-band upper limit
  71. GRB051008: Radio Observation
  72. GRB 051008: Swift XRT position
  73. GRB 051008, optical observations
  74. GRB 051008: early Swift XRT analysis
  75. GRB 051008: Swift UVOT Candidate
  76. GRB 051006: P60 Observations
  77. grb test
  78. GRB 051006: XRT refined analysis
  79. GRB 051006: optical observations at Sierra Nevada
  80. GRB 051006: XRT position
  81. GRB 050906, summary of radio observations
  82. GRB 050925: Second Epoch WSRT Radio Observations
  83. GRB 051001: Swift XRT refined analysis
  84. GRB 051001, optical observations at Mt. John
  85. GRB 051001: I-band limit
  86. GRB 051001: AAT infra-red observations
  87. GRB 051001: Swift-BAT refined analysis
  88. GRB 051001: Swift Detection of a Burst
  89. GRB 051001: ROTSE-III Optical Limits
  90. GRB050908: optical observations
  91. GRB050922C: optical observation
  92. GRB050922B: optical limit
  93. GRB 050922C: further VLT observations
  94. GRB 050820A: NIR photometry at the TNG
  95. GRB050922C: UVES/VLT high resolution spectroscopy
  96. GRB050925: Swift/XRT limits
  97. GRB/SGR 050925: IR Observations
  98. GRB 050922C: break in the lightcurve
  99. GRB 050925: WSRT Radio Observations
  100. GRB 050925 : I-band observation at Xinglong observatory

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