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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"

25039 results found.

  1. GRB051109A: XRT refined analysis
  2. GRB 051109B: Super-LOTIS Observations
  3. GRB051105B: REM Optical observation
  4. GRB 051109B: Swift detection of a burst
  5. GRB 051109: Rc and Ic observations
  6. GRB 051109: Swift-BAT refined analysis
  7. GRB 051109a: IR Photometry and Astrometry
  8. GRB051109: Swift detection of a burst
  9. GRB 051109a: IR Detections
  10. GRB051105B: Swift/XRT upper limit
  11. GRB051105B: Swift/UVOT upper limit
  12. GRB051103: MASTER: OT limit and host galaxy candidates
  13. GRB051028: Swift-XRT refined analysis
  14. GRB 051105a, observation from Naini Tal and OSN
  15. GRB 051105a: MDM Observations
  16. GRB 051105A: TNG optical observations
  17. GRB051105A: Swift/UVOT Observations
  18. GRB 051105A, radio observations
  19. GRB051103:_MASTER_optical_observations
  20. IPN triangulation and Konus spectrum of the bright short/hard GRB051103
  21. GRB 051105A, optical observations
  22. XRT observations of GRB 051105A
  23. GRB 051105b: ART optical limits
  24. GRB 051105B (INTEGRAL 2701): Optical observation
  25. GRB 051105: Swift detection of a short burst
  26. Recent GRB UBVRcIc field photometry
  27. GRB051028 SARA Observation
  28. GRB051028: optical observations
  29. GRB051028: Swift/UVOT upper limits
  30. GRB051028: Swift XRT Position
  31. GRB051028:MASTER observations
  32. GRB051021B: Swift/UVOT Upper limits
  33. GRB 051021, Optical Observations
  34. GRB 051022: XRT Refined Spectral and Temporal Analysis
  35. GRB051012: Swift-XRT analysis
  36. GRB051021B: Swift XRT refined analysis
  37. GRB 051022, mm counterpart
  38. GRB 051022: Swift/UVOT Upper Limits
  39. GRB051022: Radio Counterpart
  40. GRB051022: IR observations
  41. GRB051021A: Swift XRT refined analysis
  42. GRB051022: Optical Observations
  43. GRB051021b: Magellan IR Imaging
  44. GRB 051021, SMARTS optical/IR observations
  45. GRB051022: Swift XRT Position
  46. GRB 051021: P200 Ks Observations
  47. GRB 051022 (=H3950): SXC Flight Localization is Valid
  48. GRB051021: Swift/UVOT Upper Limits
  49. GRB 051021B: Refined analysis of the Swift-BAT burst
  50. GRB 051022: SSO40 Optical Observations
  51. GRB051022,optical observation
  52. GRB 051021,optical observation
  53. GRB 051021B: Swift detection of a burst
  54. GRB 051021 : optical afterglow observation at Lulin
  55. GRB 051021: Optical observations and candidate afterglow
  56. GRB051021.63
  57. GRB051021.6: MASTER optical observation
  58. GRB051021: A GRB Localized by HETE
  59. Swift-BAT triggered on a posible CR Shower or possible GRB
  60. GRB 051016b: Optical limit
  61. Afterglow candidate of GRB 051016B observed at Lulin
  62. GRB 051016A: Swift/UVOT upper limits
  63. GRB 051016B: refined analysis of the Swift/XRT data
  64. GRB 051016B: Swift/UVOT detection
  65. GRB 051016B,optical observation
  66. GRB 051016B : Optical follow-up at Lulin
  67. GRB 051016B: Refined analysis of the Swift-BAT burst
  68. GRB 051016B: Swift detection of a soft burst
  69. GRB 051016: Swift-BAT refined analysis
  70. GRB051016 XMM-Newton observation
  71. GRB051016: Swift XRT refined analysis.
  72. GRB 051016: PROMPT Observations
  73. GRB051016: Swift detection of a burst
  74. Photometric calibration of Swift/UVOT and Re-analysis of Swift/UVOT GRB 050922C data
  75. GRB 051012: Swift-BAT detection of burst yesterday
  76. Swift-BAT Trigger 159578 is a possible burst
  77. GRB 051006: Swift/UVOT Upper Limits
  78. GRB051008: optical candidate
  79. GRB 051008 - a low redshift low-luminosity burst?
  80. GRB051011: bright nebulae near error box
  81. GRB051011: MASTER optical observation
  82. GRB051008: Final refined analysis of the Swift-BAT burst
  83. GRB051008: Radio Observation
  84. GRB 051008, optical observations
  85. GRB 051008: early Swift XRT analysis
  86. GRB 051008: Swift UVOT Candidate
  87. GRB 051006: P60 Observations
  88. Swift-BAT trigger 158700 is a probable Cosmic Ray Shower Event
  89. GRB 051006: optical observations at Sierra Nevada
  90. GRB051006: Refined analysis of the Swift-BAT burst
  91. GRB051006: Swift detection of a burst
  92. GRB 050906, summary of radio observations
  93. GRB051001: Swift UVOT Upper Limits
  94. GRB 050925: Second Epoch WSRT Radio Observations
  95. GRB 051001: I-band limit
  96. GRB 051001: AAT infra-red observations
  97. GRB 051001: Swift-BAT refined analysis
  98. GRB 051001: Swift Detection of a Burst
  99. GRB 050820A: NIR photometry at the TNG
  100. GRB050925: Swift/XRT limits

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