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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"

2722 results found.

  1. GRB 080129: GROND detection in all bands, and fading
  2. GRB 080129: GROND detection of the optical/NIR afterglow, and fading
  3. IPN triangulation of GRB080122
  4. GRB 080121: Nearby SDSS galaxies
  5. GRB 080120: Swift-XRT refined analysis
  6. GRB080120: Swift XRT position
  7. GRB 071227: Swift detection of a burst
  8. GRB071020: optical observations
  9. GRB 071122 Swift-XRT refined analysis
  10. GRB 071122: Corrected P60 Coordinates
  11. GRB 071122: P60 Optical Afterglow Candidate
  12. GRB 071122: Swift detection of a burst
  13. GRB 071118, Swift-BAT refined analysis
  14. VLT FORS2 observations of short hard GRB071112B
  15. ATCA radio observations of short hard burst GRB 071112B
  16. GRB 071112C: SARA upper limit
  17. GRB 071112C: ROTSE-III Confirmation of Optical Counterpart
  18. GRB 071028B Swift-BAT detection of a burst
  19. GRB 071025: Kuiper Telescope Optical Observations
  20. GRB 071025, Swift-BAT refined analysis
  21. GRB 071010A: Late-time Keck/LRIS photometry - possible host galaxy and jet break
  22. GRB 071013: TNT optical data refined analysis
  23. GRB 071010B: Photometry after 1.6 days
  24. GRB 071010A: Continued Keck Imaging
  25. GRB 071006, Swift-BAT refined analysis
  26. GRB 071010B: Swift detection of a burst
  27. Recent SGR1806-20 Activity
  28. GRB 070917: Swift detection of a bright burst
  29. GRB 070808, Swift-BAT refined analysis
  30. Swift trigger on 4U 1700-377 while star tracker loss-of-lock
  31. GRB 070729, Swift-BAT refined analysis
  32. GRB 070724B: Swift-XRT afterglow likely candidate
  33. GRB 070721A : Faulkes Telescope South optical limit
  34. GRB 070721A, Swift-BAT refined analysis
  35. GRB 070621: Watcher Observations
  36. GRB070520B: optical observations
  37. GRB 070521, optical observation
  38. GRB 070521, Swift-BAT refined analysis
  39. GRB 070521: optical limit by Pi of the Sky
  40. GRB 070419A: RAPTOR Detection of Early Emission
  41. GRB070330: Correction to UVOT position
  42. UVOT observations of GRB070330
  43. GRB 070330, Swift-BAT refined analysis
  44. GRB 070330: Swift-XRT refined analysis
  45. GRB 070330: Swift detection of a burst
  46. GRB 070311: MDM Optical Detection
  47. GRB070227: Swift-XRT refined analysis
  48. VLA observation of GRB 070224
  49. GRB 070227: optical observations
  50. GRB 070227: optical observations
  51. GRB 070209: Swift XRT analysis
  52. GRB 070103: Swift detection of a burst
  53. Retractions of previous Swift-BAT triggers
  54. GRB 061201: Magellan Redshift of nearby Abell cluster
  55. GRB061202 optical limit by "Pi of the Sky"
  56. RHESSI Spectrum of GRB061126
  57. GRB 061126: SARA Observations
  58. GRB 061126: Swift detection of a burst
  59. GRB061122: Swift/UVOT Optical Observations
  60. GRB 061110: Swift detection of a burst
  61. GRB061019: second epoch CrAO observations
  62. GRB 061028: MDM Observations
  63. GRB 061028, Swift-BAT refined analysis
  64. GRB061019: optical observations
  65. GRB 061007: Second Epoch ATCA Radio Observations
  66. GRB 061007: ATCA Radio Observations
  67. GRB060912: Swift/UVOT Observations
  68. GRB060904b optical detections (delayed report due to internet outage)
  69. GRB 060904B: RTT150 optical observations
  70. Two bright bursts from SGR 1806-20 detected with IBAS
  71. GRB 060825: VLA observations
  72. GRB 060825: XRT Team Refined Analysis
  73. GRB 060825: Swift-BAT Refined Analysis
  74. GRB060825: BOOTES-IR optical observations
  75. Konus-Wind observation of GRB 060813
  76. Swift detection of an outburst from the 4U 1246-58 LMXB burster
  77. GRB 060805: Swift detection of a burst
  78. GRB 060801, optical observation
  79. GRB 060605: SkyNet Optical Limits
  80. GRB 060712: Swift detection of a burst
  81. GRB 060502B: A Bright Early-type Galaxy as Putative Host of the Short Burst
  82. GRB 060607: REM NIR afterglow
  83. GRB 060522: Swift detection of a burst with possible optical afterglow
  84. GRB 060516: Swift detection of a burst
  85. GRB060501: P60 imaging and afterglow candidate
  86. GRB060428B, optical observation
  87. GRB060424: optical afterglow detection
  88. GRB 060424: Refined analysis of the Swift-BAT burst
  89. GRB 060403: Swift detection of a burst
  90. GRB 060312: ROTSE-III Optical Limits
  91. Bright short hard GRB 060303: IPN localization and Konus spectrum
  92. GRB 060223B: Swift XRT possible afterglow
  93. GRB 060218/SN 2006aj: RBO optical observations
  94. GRB 060223B: ART optical limits
  95. GRB 060206: Swift/UVOT Observations
  96. GRB 060209(?): Swift-BAT detection of a possible burst
  97. GRB060206: Swift-BAT detection of a burst
  98. GRB060124: detailed XRT analysis
  99. GRB 060123: Swift detection of a very long, faint burst
  100. GRB 060117: PROMPT Observations

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