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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"

20947 results found.

  1. GRB051109A - radio observations
  2. GRB 051109b: GETS observation
  3. GRB 051109B: ROTSE-III Optical Limits
  4. GRB 051109A: Swift-UVOT Observations
  5. GRB051109B: no UVOT source detected
  6. GRB 051109B : Lulin Optical Observations
  7. GRB 051109B: Super-LOTIS Observations
  8. GRB 051109B Kiso optical follow-up observation
  9. GRB051105B: REM Optical observation
  10. GRB 051109B: Swift detection of a burst
  11. GRB 051109: PROMPT Detections
  12. GRB 051109: Rc and Ic observations
  13. GRB 051109a: IR Photometry and Astrometry
  14. GRB051109: Swift detection of a burst
  15. GRB 051109a: IR Detections
  16. GRB051105B: Swift/XRT upper limit
  17. GRB051105B: Swift/UVOT upper limit
  18. GRB051103: optical observations
  19. GRB 051105a, observation from Naini Tal and OSN
  20. GRB 051105a: MDM Observations
  21. GRB 051105A: TNG optical observations
  22. GRB051105A: Swift/UVOT Observations
  23. GRB 051105A, radio observations
  24. IPN triangulation and Konus spectrum of the bright short/hard GRB051103
  25. XRT observations of GRB 051105A
  26. GRB 051105: Optical limit
  27. GRB 051105: Swift detection of a short burst
  28. Recent GRB UBVRcIc field photometry
  29. GRB051028 SARA Observation
  30. GRB051028: Swift/UVOT upper limits
  31. GRB051028: Swift XRT Position
  32. GRB051022: Swift XRT measurement of jet break
  33. GRB051021B: Swift/UVOT Upper limits
  34. GRB 051021, Optical Observations
  35. GRB051012: Swift-XRT analysis
  36. GRB 051022, mm counterpart
  37. GRB 051022: Swift/UVOT Upper Limits
  38. GRB051022: Radio Counterpart
  39. GRB051022: IR observations
  40. GRB051021A: Swift XRT refined analysis
  41. GRB051022: Optical Observations
  42. GRB 051021: PROMPT RcIc Observations
  43. GRB051021b: Magellan IR Imaging
  44. GRB051022: Swift XRT Position
  45. GRB 051021: P200 Ks Observations
  46. IPN triangulation of GRB051022 (=H3950)
  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 051022A: ROTSE-III Optical Limits
  53. GRB 051021,optical observation
  54. GRB 051021B: Swift detection of a burst
  55. GRB051021: Swift XRT analysis
  56. Swift-BAT triggered on a posible CR Shower or possible GRB
  57. GRB 050502b: Optical limit
  58. Afterglow candidate of GRB 051016B observed at Lulin
  59. GRB 051016A: Swift/UVOT upper limits
  60. GRB 051016B: Swift/UVOT detection
  61. GRB 051016B,optical observation
  62. GRB 051016B : Optical follow-up at Lulin
  63. GRB 051016B: Swift detection of a soft burst
  64. GRB051016 XMM-Newton observation
  65. GRB 051016: LCO optical and near-IR imaging
  66. GRB 051016: PROMPT Observations
  67. GRB051016: Swift detection of a burst
  68. GRB051006: optical observations
  69. GRB 051012: Swift-BAT detection of burst yesterday
  70. Swift-BAT Trigger 159578 is a possible burst
  71. GRB050805A: Rc optical observations
  72. GRB 051006: Swift/UVOT Upper Limits
  73. GRB051008: optical candidate
  74. GRB 051008 - a low redshift low-luminosity burst?
  75. GRB051008: Swift XRT refined analysis
  76. GRB051008: Radio Observation
  77. GRB 051008, optical observations
  78. GRB 051008: early Swift XRT analysis
  79. GRB 051008: Swift UVOT Candidate
  80. GRB051008: Swift-BAT detection of a bright burst
  81. GRB 051006: P60 Observations
  82. GRB 051006: XRT refined analysis
  83. Swift-BAT trigger 158700 is a probable Cosmic Ray Shower Event
  84. GRB 051006: optical observations at Sierra Nevada
  85. GRB051006: Refined analysis of the Swift-BAT burst
  86. GRB051006: Swift detection of a burst
  87. GRB 050906, summary of radio observations
  88. GRB051001: Swift UVOT Upper Limits
  89. GRB 050925: Second Epoch WSRT Radio Observations
  90. GRB 051001: AAT infra-red observations
  91. GRB 051001: Swift Detection of a Burst
  92. GRB 051001: ROTSE-III Optical Limits
  93. GRB 050820A: NIR photometry at the TNG
  94. GRB050925: Swift/XRT limits
  95. GRB/SGR 050925: IR Observations
  96. GRB 050925: WSRT Radio Observations
  97. GRB050925: Swift UVOT upper limits
  98. GRB 050925 : I-band observation at Xinglong observatory
  99. GRB050925: Faulkes Telescope North R-band limit
  100. GRB050925: Swift-BAT detection of a short burst

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