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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"

28043 results found.

  1. GRB051109B: XRT refined analysis
  2. GRB 051109B : Lulin Optical Observations
  3. GRB 051109A : Lulin BVRI Optical afterglow observation
  4. GRB051109A: further steepening in the X-ray light curve
  5. GRB051109A: XRT refined analysis
  6. GRB 051109B: Super-LOTIS Observations
  7. GRB051105B: REM Optical observation
  8. GRB 051109B: Swift detection of a burst
  9. GRB 051109: Rc and Ic observations
  10. GRB 051109: Swift-BAT refined analysis
  11. GRB 051109a: IR Photometry and Astrometry
  12. GRB051109: Swift detection of a burst
  13. GRB 051109a: IR Detections
  14. GRB051105B: Swift/XRT upper limit
  15. GRB051105B: Swift/UVOT upper limit
  16. GRB051103: MASTER: OT limit and host galaxy candidates
  17. GRB051028: Swift-XRT refined analysis
  18. GRB 051105a, observation from Naini Tal and OSN
  19. GRB 051105a: MDM Observations
  20. GRB 051105A: TNG optical observations
  21. GRB051105A: Swift/UVOT Observations
  22. GRB 051105A, radio observations
  23. GRB051103:_MASTER_optical_observations
  24. IPN triangulation and Konus spectrum of the bright short/hard GRB051103
  25. GRB 051105A, optical observations
  26. XRT observations of GRB 051105A
  27. GRB 051105b: ART optical limits
  28. GRB 051105B (INTEGRAL 2701): Optical observation
  29. GRB 051105: Swift detection of a short burst
  30. Recent GRB UBVRcIc field photometry
  31. GRB051028 SARA Observation
  32. GRB051028: optical observations
  33. GRB051028: Swift/UVOT upper limits
  34. GRB051028: Swift XRT Position
  35. GRB051028:MASTER observations
  36. GRB051021B: Swift/UVOT Upper limits
  37. GRB 051021, Optical Observations
  38. GRB 051022: XRT Refined Spectral and Temporal Analysis
  39. GRB051012: Swift-XRT analysis
  40. GRB051021B: Swift XRT refined analysis
  41. GRB 051022, mm counterpart
  42. GRB 051022: Swift/UVOT Upper Limits
  43. GRB051022: Radio Counterpart
  44. GRB051022: IR observations
  45. GRB051021A: Swift XRT refined analysis
  46. GRB051022: Optical Observations
  47. GRB051021b: Magellan IR Imaging
  48. GRB 051021, SMARTS optical/IR observations
  49. GRB051022: Swift XRT Position
  50. GRB 051021: P200 Ks Observations
  51. GRB 051022 (=H3950): SXC Flight Localization is Valid
  52. GRB051021: Swift/UVOT Upper Limits
  53. GRB 051021B: Refined analysis of the Swift-BAT burst
  54. GRB 051022: SSO40 Optical Observations
  55. GRB051022,optical observation
  56. GRB 051021,optical observation
  57. GRB 051021B: Swift detection of a burst
  58. GRB 051021 : optical afterglow observation at Lulin
  59. GRB 051021: Optical observations and candidate afterglow
  60. GRB051021.63
  61. GRB051021.6: MASTER optical observation
  62. GRB051021: A GRB Localized by HETE
  63. Swift-BAT triggered on a posible CR Shower or possible GRB
  64. GRB 051016b: Optical limit
  65. Afterglow candidate of GRB 051016B observed at Lulin
  66. GRB 051016A: Swift/UVOT upper limits
  67. GRB 051016B: refined analysis of the Swift/XRT data
  68. GRB 051016B: Swift/UVOT detection
  69. GRB 051016B,optical observation
  70. GRB 051016B : Optical follow-up at Lulin
  71. GRB 051016B: Refined analysis of the Swift-BAT burst
  72. GRB 051016B: Swift detection of a soft burst
  73. GRB 051016: Swift-BAT refined analysis
  74. GRB051016 XMM-Newton observation
  75. GRB051016: Swift XRT refined analysis.
  76. GRB 051016: PROMPT Observations
  77. GRB051016: Swift detection of a burst
  78. Photometric calibration of Swift/UVOT and Re-analysis of Swift/UVOT GRB 050922C data
  79. GRB 051012: Swift-BAT detection of burst yesterday
  80. Swift-BAT Trigger 159578 is a possible burst
  81. GRB 051006: Swift/UVOT Upper Limits
  82. GRB051008: optical candidate
  83. GRB 051008 - a low redshift low-luminosity burst?
  84. GRB051011: bright nebulae near error box
  85. GRB051011: MASTER optical observation
  86. GRB051008: Final refined analysis of the Swift-BAT burst
  87. GRB051008: Radio Observation
  88. GRB 051008, optical observations
  89. GRB 051008: early Swift XRT analysis
  90. GRB 051008: Swift UVOT Candidate
  91. GRB 051006: P60 Observations
  92. Swift-BAT trigger 158700 is a probable Cosmic Ray Shower Event
  93. GRB 051006: optical observations at Sierra Nevada
  94. GRB051006: Refined analysis of the Swift-BAT burst
  95. GRB051006: Swift detection of a burst
  96. GRB 050906, summary of radio observations
  97. GRB051001: Swift UVOT Upper Limits
  98. GRB 050925: Second Epoch WSRT Radio Observations
  99. GRB 051001: I-band limit
  100. GRB 051001: AAT infra-red observations

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