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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"

28042 results found.

  1. GRB 051109B : Lulin Optical Observations
  2. GRB 051109A : Lulin BVRI Optical afterglow observation
  3. GRB051109A: further steepening in the X-ray light curve
  4. GRB051109A: XRT refined analysis
  5. GRB 051109B: Super-LOTIS Observations
  6. GRB051105B: REM Optical observation
  7. GRB 051109B: Swift detection of a burst
  8. GRB 051109: Rc and Ic observations
  9. GRB 051109: Swift-BAT refined analysis
  10. GRB 051109a: IR Photometry and Astrometry
  11. GRB051109: Swift detection of a burst
  12. GRB 051109a: IR Detections
  13. GRB051105B: Swift/XRT upper limit
  14. GRB051105B: Swift/UVOT upper limit
  15. GRB051103: MASTER: OT limit and host galaxy candidates
  16. GRB051028: Swift-XRT refined analysis
  17. GRB 051105a, observation from Naini Tal and OSN
  18. GRB 051105a: MDM Observations
  19. GRB 051105A: TNG optical observations
  20. GRB051105A: Swift/UVOT Observations
  21. GRB 051105A, radio observations
  22. GRB051103:_MASTER_optical_observations
  23. IPN triangulation and Konus spectrum of the bright short/hard GRB051103
  24. GRB 051105A, optical observations
  25. XRT observations of GRB 051105A
  26. GRB 051105b: ART optical limits
  27. GRB 051105B (INTEGRAL 2701): Optical observation
  28. GRB 051105: Swift detection of a short burst
  29. Recent GRB UBVRcIc field photometry
  30. GRB051028 SARA Observation
  31. GRB051028: optical observations
  32. GRB051028: Swift/UVOT upper limits
  33. GRB051028: Swift XRT Position
  34. GRB051028:MASTER observations
  35. GRB051021B: Swift/UVOT Upper limits
  36. GRB 051021, Optical Observations
  37. GRB 051022: XRT Refined Spectral and Temporal Analysis
  38. GRB051012: Swift-XRT analysis
  39. GRB051021B: Swift XRT refined analysis
  40. GRB 051022, mm counterpart
  41. GRB 051022: Swift/UVOT Upper Limits
  42. GRB051022: Radio Counterpart
  43. GRB051022: IR observations
  44. GRB051021A: Swift XRT refined analysis
  45. GRB051022: Optical Observations
  46. GRB051021b: Magellan IR Imaging
  47. GRB 051021, SMARTS optical/IR observations
  48. GRB051022: Swift XRT Position
  49. GRB 051021: P200 Ks Observations
  50. GRB 051022 (=H3950): SXC Flight Localization is Valid
  51. GRB051021: Swift/UVOT Upper Limits
  52. GRB 051021B: Refined analysis of the Swift-BAT burst
  53. GRB 051022: SSO40 Optical Observations
  54. GRB051022,optical observation
  55. GRB 051021,optical observation
  56. GRB 051021B: Swift detection of a burst
  57. GRB 051021 : optical afterglow observation at Lulin
  58. GRB 051021: Optical observations and candidate afterglow
  59. GRB051021.63
  60. GRB051021.6: MASTER optical observation
  61. GRB051021: A GRB Localized by HETE
  62. Swift-BAT triggered on a posible CR Shower or possible GRB
  63. GRB 051016b: Optical limit
  64. Afterglow candidate of GRB 051016B observed at Lulin
  65. GRB 051016A: Swift/UVOT upper limits
  66. GRB 051016B: refined analysis of the Swift/XRT data
  67. GRB 051016B: Swift/UVOT detection
  68. GRB 051016B,optical observation
  69. GRB 051016B : Optical follow-up at Lulin
  70. GRB 051016B: Refined analysis of the Swift-BAT burst
  71. GRB 051016B: Swift detection of a soft burst
  72. GRB 051016: Swift-BAT refined analysis
  73. GRB051016 XMM-Newton observation
  74. GRB051016: Swift XRT refined analysis.
  75. GRB 051016: PROMPT Observations
  76. GRB051016: Swift detection of a burst
  77. Photometric calibration of Swift/UVOT and Re-analysis of Swift/UVOT GRB 050922C data
  78. GRB 051012: Swift-BAT detection of burst yesterday
  79. Swift-BAT Trigger 159578 is a possible burst
  80. GRB 051006: Swift/UVOT Upper Limits
  81. GRB051008: optical candidate
  82. GRB 051008 - a low redshift low-luminosity burst?
  83. GRB051011: bright nebulae near error box
  84. GRB051011: MASTER optical observation
  85. GRB051008: Final refined analysis of the Swift-BAT burst
  86. GRB051008: Radio Observation
  87. GRB 051008, optical observations
  88. GRB 051008: early Swift XRT analysis
  89. GRB 051008: Swift UVOT Candidate
  90. GRB 051006: P60 Observations
  91. Swift-BAT trigger 158700 is a probable Cosmic Ray Shower Event
  92. GRB 051006: optical observations at Sierra Nevada
  93. GRB051006: Refined analysis of the Swift-BAT burst
  94. GRB051006: Swift detection of a burst
  95. GRB 050906, summary of radio observations
  96. GRB051001: Swift UVOT Upper Limits
  97. GRB 050925: Second Epoch WSRT Radio Observations
  98. GRB 051001: I-band limit
  99. GRB 051001: AAT infra-red observations
  100. GRB 051001: Swift-BAT refined analysis

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