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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').
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"

27247 results found.

  1. LIGO/Virgo G275697: Further Swift-XRT sources
  2. Fermi GBM trigger 510207699/170303182 is not a GRB
  3. LIGO/Virgo G275697: MAXI/GSC observations
  4. GRB 170228B CALET Gamma-Ray Burst Monitor detection
  5. LIGO/Virgo G275404: Nearby Galaxies in the Localization Volume
  6. LIGO/Virgo G275697: Further Swift-XRT sources
  7. LIGO/Virgo G275697: Fermi GBM Upper Limits
  8. LIGO/Virgo G275697: AstroSat CZTI upper limits
  9. LIGO/Virgo G275697: optical spectroscopy of Swift/XRT source 1
  10. LIGO/Virgo G275697: SVOM/Mini-GWAC observations of the initial skymap
  11. GRB 170228B: POLAR Observation
  12. LIGO/Virgo G275404: Fermi GBM Upper Limits
  13. GRB 170228A: AstroSat CZTI detection
  14. GRB 170228A: Fermi GBM observation
  15. GRB 170228A: Fermi-LAT detection
  16. LIGO/Virgo G275697: CALET Observations
  17. LIGO/Virgo G275697: MASTER automatic follow up detection
  18. LIGO/Virgo G275697: CNEOST optical observations
  19. LIGO/Virgo G274296 and G275404 : MAXI/GSC observations
  20. LIGO/Virgo G275404: Nearby Galaxies in the Localization Region
  21. LIGO/Virgo G275697: Fermi-LAT search for a high-energy gamma-ray counterpart
  22. LIGO/Virgo G275697: REM optical/NIR observations
  23. LIGO/Virgo G275697: Swift-XRT sources
  24. LIGO/Virgo G275697: Swift/BAT data search
  25. LIGO/Virgo G275697: AGILE-GRID preliminary analysis
  26. LIGO/Virgo G275697: INTEGRAL search for a prompt gamma-ray counterpart
  27. LIGO/VIRGO G275697: Fermi GBM Observations
  28. LIGO/Virgo G275404: AstroSat CZTI upper limits
  29. LIGO/Virgo G275697: IceCube neutrino observations
  30. LIGO/Virgo G275404: REM optical/NIR observations
  31. LIGO/Virgo G275404: Fermi-LAT search for a high-energy gamma-ray counterpart
  32. LIGO/Virgo G275404: INTEGRAL search for a prompt gamma-ray counterpart
  33. LIGO/Virgo G275404: AGILE-GRID detection of a possible gamma-ray transient
  34. LIGO/Virgo G275404: Swift-XRT sources
  35. GRB 170222A: CALET Gamma-Ray Burst Monitor detection
  36. LIGO/Virgo G275404: Swift/BAT data search
  37. LIGO/Virgo G275404: SVOM/Mini-GWAC: Observations of initial skymap
  38. LIGO/Virgo G274296: Swift/BAT data search
  39. LIGO/Virgo G275404: AGILE-GRID preliminary analysis
  40. LIGO/Virgo G275404: Fermi GBM Observations
  41. LIGO/Virgo G275404: IceCube neutrino observations
  42. LIGO/Virgo G275404: MASTER automatic follow up observations
  43. LIGO/Virgo G274296: CALET Observations
  44. GRB 170222A: Fermi GBM observation
  45. LIGO/Virgo G274296: HAWC follow-up
  46. IPN Triangulation of GRB 170222A (short/hard)
  47. GRB 170219A: POLAR Observation
  48. Swift Trigger 739517 is probably not a GRB
  49. LIGO/Virgo G274296: Asiago 1.82m Optical Observations
  50. GRB 170219A: CALET Gamma-Ray Burst Monitor detection
  51. LIGO/Virgo G274296: IceCube neutrino observations
  52. LIGO/Virgo G274296: Fermi-LAT search for a high-energy gamma-ray counterpart
  53. GRB 170219A: Fermi GBM observation
  54. LIGO/Virgo G274296: AstroSat CZTI upper limits
  55. IPN Triangulation of GRB 170219A (short/hard)
  56. LIGO/Virgo G274296: CNEOST imaging coverage and an optical transient
  57. LIGO/Virgo G274296: SWASP optical imaging coverage
  58. LIGO/Virgo G274296: Observations of initial skymap by project Mini-GWAC of SVOM
  59. LIGO/Virgo G274296: INTEGRAL search for a prompt gamma-ray counterpart
  60. LIGO/Virgo G274296: REM optical/NIR observations
  61. LIGO/VIRGO G274296: Fermi GBM Observations
  62. LIGO/VIRGO G274296: AGILE-GRID preliminary analysis
  63. Trigger 738728: Swift triggered on noise near NGC 4096
  64. GRB170214A: RATIR Optical and NIR Afterglow Confirmation
  65. GRB 170214A: GROND detection in all bands
  66. GRB 170214A: NOT optical afterglow confirmation
  67. GRB 170214A: Swift/UVOT Upper Limits
  68. GRB170214A: RATIR Optical and NIR Observations
  69. GRB 170209A: GROND confirmation of MASTER afterglow
  70. GRB 170214A: Fermi-LAT detection
  71. GRB 170214A: Fermi GBM detection
  72. GRB 170208A: AstroSat CZTI detection
  73. GRB 170209A: AstroSat CZTI detection
  74. LIGO/Virgo G270580: DLT40 follow-up observation
  75. GRB 170208C: POLAR Observation
  76. IBAS Trigger 7691 is not a GRB
  77. GRB 170210A: Fermi GBM observation
  78. GRB 170208B: Swift/UVOT Upper Limits
  79. GRB 170208B: RATIR Optical and NIR Observations
  80. GRB 170208B: Swift-BAT refined analysis
  81. GRB 170208A: Swift-BAT refined analysis
  82. GRB 170209A: Fermi GBM Detection
  83. Fermi Trigger 508295323: MASTER-OAFA possible OT detection
  84. GRB 170208A: Swift-XRT refined Analysis
  85. LIGO/Virgo G270580: AstroSat CZTI upper limits
  86. GRB 170208B: Fermi GBM Detection
  87. GRB 170207A: POLAR Observation
  88. GRB 170208A: Swift/UVOT Upper Limits
  89. GRB 170207A: AstroSat CZTI detection
  90. GRB 170208B: GROND observations
  91. GRB 170206C: POLAR Observation
  92. GRB 170208B: NOT upper limits
  93. GRB 170208B: Swift-XRT refined Analysis
  94. GRB 170208B: Etelman observatory optical observations
  95. GRB 170208A: Fermi GBM Detection
  96. GRB 170208B: Swift detection of a burst
  97. GRB 170208A: Swift detection of a burst
  98. GRB 170207A: Fermi GBM observation
  99. IPN Triangulation of GRB 170207A (long/very bright)
  100. GRB 170206B: Swift/UVOT Upper Limits

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