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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

12190 results found.

  1. LIGO/Virgo G275697: Further Swift-XRT sources
  2. GRB 170306A: LCO Cerro Tololo observations
  3. GRB 170306A: Swift detection of a burst
  4. LIGO/Virgo G275404: Liverpool Telescope classification of EM candidates
  5. LIGO/Virgo G275697: Further Swift-XRT sources
  6. Konus-Wind observation of GRB 170228A
  7. LIGO/Virgo G275697: MAXI/GSC observations
  8. GRB 170228B CALET Gamma-Ray Burst Monitor detection
  9. LIGO/Virgo G275697: Additional iPTF Optical Transient Candidates
  10. LIGO/Virgo G275404: Additional iPTF Optical Transient Candidates
  11. LIGO/Virgo G275404: Nearby Galaxies in the Localization Volume
  12. LIGO/Virgo G268556, G270580, G274296, and G275404: Konus-Wind observations
  13. LIGO/Virgo G275404: iPTF Optical Transient Candidates
  14. GRB 170228A: Fermi-LAT detection
  15. LIGO/Virgo G275404: A near-infrared transient in the error circle of AGL J1914+1043
  16. LIGO/Virgo G275697: CNEOST optical observations
  17. LIGO/Virgo G274296 and G275404 : MAXI/GSC observations
  18. LIGO/Virgo G275404: Nearby galaxy observations by J-GEM collaboration
  19. LIGO/Virgo G275404: Nearby Galaxies in the Localization Region
  20. LIGO/Virgo G275697: Fermi-LAT search for a high-energy gamma-ray counterpart
  21. LIGO/Virgo G275697: INTEGRAL search for a prompt gamma-ray counterpart
  22. LIGO/Virgo G275404: Fermi-LAT search for a high-energy gamma-ray counterpart
  23. LIGO/Virgo G275404: AGILE-GRID detection of a possible gamma-ray transient
  24. LIGO/Virgo G275404: SVOM/Mini-GWAC: Observations of initial skymap
  25. GRB 170220A: POLAR Observation
  26. Konus-Wind observation of GRB 170222A
  27. LIGO/Virgo G274296: CALET Observations
  28. LIGO/Virgo G274296: PS17bek is a superluminous supernova at z=0.31
  29. LIGO/Virgo G274296: J-GEM optical/NIR follow-up observations
  30. GRB 170219A: POLAR Observation
  31. Swift Trigger 739517 is probably not a GRB
  32. LIGO/Virgo G274296: Asiago 1.82m Optical Observations
  33. LIGO/Virgo G274296: PSN MASTER OT J042250.16-820415.4 is before maximum
  34. LIGO/Virgo G274296: PESSTO classification of 9 Pan-STARRS transients
  35. LIGO/Virgo G274296: Fermi-LAT search for a high-energy gamma-ray counterpart
  36. Konus-Wind observation of GRB 170219A (short/hard)
  37. IPN Triangulation of GRB 170219A (short/hard)
  38. LIGO/Virgo G274296: Optical Observation
  39. LIGO/Virgo G274296: Pan-STARRS imaging and discovery of 70 transients
  40. LIGO/Virgo G274296: SWASP optical imaging coverage
  41. LIGO/Virgo G274296: Observations of initial skymap by project Mini-GWAC of SVOM
  42. LIGO/Virgo G274296: REM optical/NIR observations
  43. GRB 170214A: Mondy optical upper limit
  44. Konus-Wind observation of GRB 170214A
  45. GRB 170214A: Fermi-LAT detection
  46. LIGO/Virgo G270580: DLT40 follow-up observation
  47. Konus-Wind observation of GRB 170210A
  48. GRB 170210A: POLAR observation
  49. GRB 170208C: POLAR Observation
  50. IPN Triangulation of GRB 170210A
  51. Konus-Wind observation of GRB 170209A
  52. GRB 170208B: Swift-BAT refined analysis
  53. LIGO/Virgo G270580: AstroSat CZTI upper limits
  54. GRB 170207A: POLAR Observation
  55. Konus-Wind observation of GRB 170208B
  56. Konus-Wind observation of GRB 170208A
  57. GRB 170206C: POLAR Observation
  58. GRB 170208B: Swift-XRT refined Analysis
  59. GRB 170208B: Swift detection of a burst
  60. Konus-Wind observation of GRB 170207A
  61. Konus-Wind observation of GRB 170206A
  62. GRB 170206A: POLAR observation
  63. IPN Triangulation of GRB 170206A (short/hard)
  64. GRB 170206A: Fermi-LAT detection
  65. Konus-Wind observation of GRB 170205A
  66. Konus-Wind observation of GRB 170202A
  67. GRB 170202B POLAR Observation
  68. GRB 170131A: POLAR Observation
  69. GRB 170202A: Swift-XRT refined Analysis
  70. GRB 170202A: T100 observations
  71. GRB 170131A detected in Swift/BAT ground processing
  72. LIGO/Virgo G270580: Las Cumbres Observatory Follow-up Observations
  73. GRB 170130A: POLAR Observation
  74. Konus-Wind observation of GRB 170127C (short/hard GRB with extended emission)
  75. GRB 170127B: Swift-BAT refined analysis
  76. GRB 170127C: POLAR Observation
  77. GRB 170127B: Swift-XRT refined Analysis
  78. GRB 170127A: Swift-XRT refined Analysis
  79. GRB 170124A: CALET Gamma-Ray Burst Monitor detection
  80. Konus-Wind observation of GRB 170126A
  81. GRB 170127C (Fermi/GBM trigger 507173752): AGILE analysis
  82. GRB 170127C: Fermi-LAT detection
  83. GRB 170127B: Swift detection of a short burst
  84. GRB 170126A: Swift-XRT refined Analysis
  85. LIGO/Virgo G270580: MAXI/GSC observations
  86. LIGO/Virgo G270580: No change to estimate of LIGO false alarm probability
  87. LIGO/Virgo G270580: Liverpool Telescope classification of EM candidates
  88. LIGO/Virgo G270580: Pan-STARRS coverage and 124 optical transients
  89. LIGO/Virgo G270580: UL50 observations
  90. GRB 170121B: MASTER early optical observations of the Swift possible XT
  91. LIGO/Virgo G270580: CALET Observations
  92. LIGO/Virgo G268556/GW170104: MAXI/GSC observations
  93. GRB 170120A: POLAR Observation
  94. LIGO/Virgo G270580: Fermi-LAT search for a high-energy gamma-ray counterpart
  95. LIGO/Virgo G270580: Two optical counterpart candidates from CNEOST
  96. LIGO/Virgo G270580: INTEGRAL search of temporally coincident prompt hard X-ray
  97. LIGO/Virgo G268556: Global MASTER Net 21 OTs detection
  98. LIGO/Virgo G270580: Mini-MegaTORTORA follow-up observations
  99. LIGO/Virgo G270580: Pan-STARRS and ATLAS observations of the skymap
  100. LIGO/Virgo G270580: Observations of initial skymap by Project Mini-GWAC of SVOM

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