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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"

4714 results found.

  1. GRB 060904B BOOTES-IR and 1.5m OSN observations
  2. GRB060904B - SDSS Pre-Burst Observations
  3. GRB 060904: TAROT optical observations
  4. GRB 060904B: Swift detection of a burst with optical counterpart
  5. GRB 060904B: ROTSE-III Detection of Optical Counterpart
  6. GRB 060904: Swift detection of a bright burst
  7. GRB060901: Optical observations
  8. Two bright bursts from SGR 1806-20 detected with IBAS
  9. GRB060825: BOOTES-IR optical observations
  10. GRB 060825: Swift detection of a burst
  11. GRB 060729, SMARTS optical/IR observations
  12. GRB 060814: P200 NIR Observations
  13. GRB 060814: Swift detection of a bright burst
  14. Swift detection of an outburst from the 4U 1246-58 LMXB burster
  15. GRB060807: Optical limiting magnitudes
  16. VLA Upper Limit on Outburst of SGR 1806-20
  17. GRB 060801, optical observation
  18. GRB 060801: Swift detection of a short burst
  19. Swift-BAT trigger 221873 is not a GRB or a Transient
  20. GRB060712: MASTER optical observation
  21. GRB120706: MASTER optical observation
  22. Host galaxy of GRB050904: 250 GHz upper limit with MAMBO at the IRAM 30m
  23. Trigger 215279: Swift detection of a possible burst (GRB 060619)
  24. GRB060512: near IR observations
  25. GRB 060610: KAIT observations
  26. GRB 070706B: Watcher upper limit
  27. GRB060602A: Swift/UVOT upper limits
  28. GRB 060605: RTT150 optical observations
  29. GRB 060605: Swift-XRT Team refined analysis
  30. GRB 060605: RTT150 optical observations
  31. GRB 060605: Swift detection of a burst with optical counterpart
  32. GRB 060605: ROTSE-III Detection of Optical Counterpart
  33. GRB060502b: optical observations
  34. GRB 060526: REM observations
  35. GRB 060526: MDM-2.4m Observations
  36. GRB 060515: Super-LOTIS Observations
  37. GRB 060515: Swift detection of a burst
  38. GRB 060512: P60 Observations
  39. GRB060512 - SDSS Pre-Burst Observations
  40. GRB060512 Name Correction: LT Afterglow detection
  41. GRB060512: Liverpool Telescope Afterglow detection
  42. GRB060507: optical afterglow detection
  43. GRB060425: new MASTER survey method
  44. GRB060502A, optical observation
  45. GRB 060502A: Swift/UVOT source detection
  46. GRB 060502B: MDM Optical Observation
  47. GRB 060502B: Swift detection of a short burst
  48. GRB060502: Super-LOTIS Observations
  49. GRB 060502: Swift detection of a burst with an optical counterpart
  50. GRB 060428B: KAIT observations
  51. GRB060428A: Swift/UVOT observations.
  52. GRB 060428: Swift detection of a burst
  53. GRB060424: optical afterglow detection
  54. GRB 060421: TTT Observations
  55. Konus-Wind observation of GRB 060418
  56. GRB060418: Optical Observations
  57. GRB060418: Swift XRT Team Refined Analysis
  58. GRB060418: Magellan/MIKE Spectroscopic Redshift
  59. GRB 060418: Swift detection of a burst with bright x-ray and optical afterglow
  60. GRB060403: optical observations
  61. SGR 1900+14: BAT observations
  62. SGR 1900+14: bright burst detected by Konus-Wind on March 28
  63. SGR 1900+14: Swift-BAT detection of a bright outburst
  64. GRB 060322: Confirmation of Swift XRT afterglow
  65. GRB 060211A: optical observation
  66. SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
  67. GRB 060322: Swift XRT afterglow candidate
  68. GRB 060323: Swift/UVOT Observations
  69. GRB 060323: Swift XRT refined analysis
  70. GRB060218/SN2006aj: optical observations
  71. GRB060319: Swift XRT refined analysis
  72. GRB060319: Swift/UVOT upper limits
  73. GRB060319: MASTER limit
  74. GRB060319: MASTER optical observation
  75. GRB 060313: Swift/UVOT Observations
  76. GRB 060313, SMARTS optical/IR observations
  77. GRB 060312: Swift detection of a burst
  78. GRB060218: analysis of the XMM-Newton observation
  79. GRB 060218/SN 2006aj: WIRO optical observations
  80. GRB 060218/SN 2006aj: RBO optical observations
  81. GRB 060218: Refined analysis of the radio afterglow
  82. GRB 060218: optical/nIR observations at La Palma
  83. GRB 060218A: ROTSE-III Possible Optical Flare
  84. Further UVOT Observations of the Candidate Optical Afterglow for GRB 060218
  85. GRB060218 : SDSS pre-burst observations
  86. GRB 060218: Swift XRT Position
  87. GRB 060218: Swift-BAT detection of a possible burst
  88. GRB 060211b: WIRO NIR Observations
  89. GRB 060211a: WIRO NIR Observations
  90. GRB 050826: Optical Afterglow and Host Galaxy
  91. GRB 060211A: Swift XRT Team Refined Analysis
  92. GRB060210:Faulkes Telescope North Afterglow Confirmation
  93. GRB 060210: candidate afterglow
  94. GRB060210: Optical afterglow
  95. Orphan GRB Afterglow candidate
  96. GRB060206: Swift XRT Refined Analysis
  97. GRB060206: P60 Optical Observations
  98. GRB060206: Swift XRT Position
  99. GRB 060204C: XRT analysis of Swift J061223.0+701243.9
  100. GRB 060203: RTT150 optical observations

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