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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').
Advanced Search

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"

3115 results found.

  1. GRB 071122: Corrected P60 Coordinates
  2. GRB 071122: P60 Optical Afterglow Candidate
  3. GRB 071122: Swift detection of a burst
  4. GRB 071118, Swift-BAT refined analysis
  5. VLT FORS2 observations of short hard GRB071112B
  6. ATCA radio observations of short hard burst GRB 071112B
  7. GRB 071112C: SARA upper limit
  8. GRB 071112C: ROTSE-III Confirmation of Optical Counterpart
  9. GRB 071028B Swift-BAT detection of a burst
  10. GRB 071025: Kuiper Telescope Optical Observations
  11. GRB 071025, Swift-BAT refined analysis
  12. GRB 071010A: Late-time Keck/LRIS photometry - possible host galaxy and jet break
  13. GRB 071013: TNT optical data refined analysis
  14. GRB 071010B: Photometry after 1.6 days
  15. GRB 071010A: Continued Keck Imaging
  16. GRB 071006, Swift-BAT refined analysis
  17. GRB 071010B: Swift detection of a burst
  18. Recent SGR1806-20 Activity
  19. GRB 070917: Swift detection of a bright burst
  20. GRB 070808, Swift-BAT refined analysis
  21. Swift trigger on 4U 1700-377 while star tracker loss-of-lock
  22. GRB 070729, Swift-BAT refined analysis
  23. GRB 070724B: Swift-XRT afterglow likely candidate
  24. GRB 070721A : Faulkes Telescope South optical limit
  25. GRB 070721A, Swift-BAT refined analysis
  26. GRB 070621: Watcher Observations
  27. GRB070520B: optical observations
  28. GRB 070521, optical observation
  29. GRB 070521, Swift-BAT refined analysis
  30. GRB 070521: optical limit by Pi of the Sky
  31. GRB 070419A: RAPTOR Detection of Early Emission
  32. GRB070330: Correction to UVOT position
  33. UVOT observations of GRB070330
  34. GRB 070330, Swift-BAT refined analysis
  35. GRB 070330: Swift-XRT refined analysis
  36. GRB 070330: Swift detection of a burst
  37. GRB 070311: MDM Optical Detection
  38. GRB070227: Swift-XRT refined analysis
  39. VLA observation of GRB 070224
  40. GRB 070227: optical observations
  41. GRB 070227: optical observations
  42. GRB 070209: Swift XRT analysis
  43. GRB 070103: Swift detection of a burst
  44. Retractions of previous Swift-BAT triggers
  45. GRB 061201: Magellan Redshift of nearby Abell cluster
  46. GRB061202 optical limit by "Pi of the Sky"
  47. RHESSI Spectrum of GRB061126
  48. GRB 061126: SARA Observations
  49. GRB 061126: Swift detection of a burst
  50. GRB061122: Swift/UVOT Optical Observations
  51. GRB 061110: Swift detection of a burst
  52. GRB061019: second epoch CrAO observations
  53. GRB 061028: MDM Observations
  54. GRB 061028, Swift-BAT refined analysis
  55. GRB061019: optical observations
  56. GRB 061007: Second Epoch ATCA Radio Observations
  57. GRB 061007: ATCA Radio Observations
  58. GRB060912: Swift/UVOT Observations
  59. GRB060904b optical detections (delayed report due to internet outage)
  60. GRB 060904B: RTT150 optical observations
  61. Two bright bursts from SGR 1806-20 detected with IBAS
  62. GRB 060825: VLA observations
  63. GRB 060825: XRT Team Refined Analysis
  64. GRB 060825: Swift-BAT Refined Analysis
  65. GRB060825: BOOTES-IR optical observations
  66. Konus-Wind observation of GRB 060813
  67. Swift detection of an outburst from the 4U 1246-58 LMXB burster
  68. GRB 060805: Swift detection of a burst
  69. GRB 060801, optical observation
  70. GRB 060605: SkyNet Optical Limits
  71. GRB 060712: Swift detection of a burst
  72. GRB 060502B: A Bright Early-type Galaxy as Putative Host of the Short Burst
  73. GRB 060607: REM NIR afterglow
  74. GRB 060522: Swift detection of a burst with possible optical afterglow
  75. GRB 060516: Swift detection of a burst
  76. GRB060501: P60 imaging and afterglow candidate
  77. GRB060428B, optical observation
  78. GRB060424: optical afterglow detection
  79. GRB 060424: Refined analysis of the Swift-BAT burst
  80. GRB 060403: Swift detection of a burst
  81. GRB 060312: ROTSE-III Optical Limits
  82. Bright short hard GRB 060303: IPN localization and Konus spectrum
  83. GRB 060223B: Swift XRT possible afterglow
  84. GRB 060218/SN 2006aj: RBO optical observations
  85. GRB 060223B: ART optical limits
  86. GRB 060206: Swift/UVOT Observations
  87. GRB 060209(?): Swift-BAT detection of a possible burst
  88. GRB060206: Swift-BAT detection of a burst
  89. GRB060124: detailed XRT analysis
  90. GRB 060123: Swift detection of a very long, faint burst
  91. GRB 060117: PROMPT Observations
  92. GRB 060116: PROMPT Observations
  93. GRB 060105: Radio observations
  94. GRB 060102 - no XRT afterglow
  95. GRB 051210: Swift/UVOT upper limits
  96. GRB051210: Swift UVOT Observation
  97. GRB 051210: Swift detection of a burst
  98. GRB051111: Swift/UVOT Observations
  99. GRB 051111: Swift-BAT refined analysis
  100. GRB051103: MASTER: OT limit and host galaxy candidates

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