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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"

24581 results found.

  1. GRB 170306B: Fermi GBM detection
  2. GRB 170306B: Fermi-LAT detection
  3. IPN Triangulation of GRB 170305A (short)
  4. LIGO/Virgo G275697: Further Swift-XRT sources
  5. GRB 170306A: LCO Cerro Tololo observations
  6. GRB170305A: Fermi GBM detection
  7. GRB 170304A: Fermi GBM observation
  8. LIGO/Virgo G275697: Further Swift-XRT sources
  9. LIGO/Virgo G275404: HAWC follow-up
  10. LIGO/Virgo G275697: Further Swift-XRT sources
  11. Konus-Wind observation of GRB 170228A
  12. LIGO/Virgo G275697: Additional iPTF Optical Transient Candidates
  13. LIGO/Virgo G275404: Additional iPTF Optical Transient Candidates
  14. LIGO/Virgo G275404: Nearby Galaxies in the Localization Volume
  15. LIGO/Virgo G275697: Fermi GBM Upper Limits
  16. LIGO/Virgo G275697: AstroSat CZTI upper limits
  17. LIGO/Virgo G268556, G270580, G274296, and G275404: Konus-Wind observations
  18. LIGO/Virgo G275697: SVOM/Mini-GWAC observations of the initial skymap
  19. LIGO/Virgo G275404: iPTF Optical Transient Candidates
  20. LIGO/Virgo G275404: Fermi GBM Upper Limits
  21. GRB 170228A: Fermi GBM observation
  22. GRB 170228A: Fermi-LAT detection
  23. LIGO/Virgo G275697: CALET Observations
  24. LIGO/Virgo G275697: MASTER automatic follow up detection
  25. LIGO/Virgo G275697: CNEOST optical observations
  26. LIGO/Virgo G274296 and G275404 : MAXI/GSC observations
  27. LIGO/Virgo G275404: Nearby Galaxies in the Localization Region
  28. LIGO/Virgo G275697: Fermi-LAT search for a high-energy gamma-ray counterpart
  29. LIGO/Virgo G275697: Konus-Wind observations
  30. LIGO/Virgo G275697: Swift/BAT data search
  31. LIGO/Virgo G275404: MASTER bright PSN detected on 27 Feb from the maximum of probability of LIGO localization
  32. LIGO/Virgo G275697: AGILE-GRID preliminary analysis
  33. LIGO/Virgo G275697: AGILE MCAL Observations
  34. LIGO/Virgo G275697: INTEGRAL search for a prompt gamma-ray counterpart
  35. LIGO/VIRGO G275697: Fermi GBM Observations
  36. LIGO/Virgo G275404: AstroSat CZTI upper limits
  37. LIGO/Virgo G275697 ANTARES search
  38. LIGO/Virgo G275697: IceCube neutrino observations
  39. LIGO/Virgo G275697: Identification of a GW CBC Candidate
  40. LIGO/Virgo G275404: MASTER OT is outside LIGO error region
  41. LIGO/Virgo G275404: Keck spectrum of MASTER OT J105958.00-115756.5
  42. LIGO/Virgo G275404: Fermi-LAT search for a high-energy gamma-ray counterpart
  43. LIGO/Virgo G275404: INTEGRAL search for a prompt gamma-ray counterpart
  44. LIGO/Virgo G275404: AGILE-GRID detection of a possible gamma-ray transient
  45. LIGO/Virgo G275404 ANTARES search
  46. LIGO/Virgo G275404: Swift/BAT data search
  47. LIGO/Virgo G275404: SVOM/Mini-GWAC: Observations of initial skymap
  48. LIGO/Virgo G274296: Swift/BAT data search
  49. LIGO/Virgo G275404: AGILE-GRID preliminary analysis
  50. LIGO/Virgo G275404: Fermi GBM Observations
  51. LIGO/Virgo G275404: AGILE MCAL observations
  52. LIGO/Virgo G275404: IceCube neutrino observations
  53. LIGO/Virgo G275404: Identification of a GW CBC Candidate
  54. LIGO/Virgo G275404: MASTER automatic follow up observations
  55. Konus-Wind observation of GRB 170222A
  56. LIGO/Virgo G274296: CALET Observations
  57. GRB 170222A: Swift-XRT observations
  58. GRB 170222A: Fermi GBM observation
  59. LIGO/Virgo G274296: HAWC follow-up
  60. LIGO/Virgo G274296: No change to estimate of LIGO false alarm probability
  61. IPN Triangulation of GRB 170222A (short/hard)
  62. GRB 170219A: POLAR Observation
  63. Swift Trigger 739517 is probably not a GRB
  64. LIGO/Virgo G274296: iPTF Optical Transient Candidates
  65. LIGO/Virgo G274296: ATLAS confirmation of the bright MASTER transient and earlier explosion date
  66. LIGO/Virgo G274296: Fermi-LAT search for a high-energy gamma-ray counterpart
  67. GRB 170219A: Fermi GBM observation
  68. LIGO/Virgo G274296: AstroSat CZTI upper limits
  69. LIGO/Virgo G274296 ANTARES search
  70. IPN Triangulation of GRB 170219A (short/hard)
  71. LIGO/Virgo G274296: CNEOST imaging coverage and an optical transient
  72. LIGO/Virgo G274296: Observations of initial skymap by project Mini-GWAC of SVOM
  73. LIGO/Virgo G274296: INTEGRAL search for a prompt gamma-ray counterpart
  74. LIGO/VIRGO G274296: Fermi GBM Observations
  75. LIGO/VIRGO G274296: AGILE-GRID preliminary analysis
  76. LIGO/Virgo G274296: Identification of a GW Burst Candidate
  77. Trigger 738728: Swift triggered on noise near NGC 4096
  78. GRB 170214A: GROND detection in all bands
  79. GRB 170214A: Swift-XRT observations
  80. Konus-Wind observation of GRB 170214A
  81. GRB 170214A: Fermi-LAT detection
  82. GRB 170214A: Fermi GBM detection
  83. GRB 170208B: SMARTS optical/IR observations
  84. LIGO/Virgo G270580: DLT40 follow-up observation
  85. Konus-Wind observation of GRB 170210A
  86. GRB 170210A: POLAR observation
  87. IBAS Trigger 7691 is not a GRB
  88. IPN Triangulation of GRB 170210A
  89. GRB 170210A: Fermi GBM observation
  90. Konus-Wind observation of GRB 170209A
  91. IPN Triangulation of GRB 170209A
  92. GRB 170208B: Swift-BAT refined analysis
  93. GRB 170208A: Swift-BAT refined analysis
  94. GRB 170209A: Fermi GBM Detection
  95. Fermi Trigger 508295323: MASTER-OAFA possible OT detection
  96. LIGO/Virgo G270580: AstroSat CZTI upper limits
  97. GRB 170208B WHT nIR candidate afterglow
  98. GRB 170208B: Fermi GBM Detection
  99. Konus-Wind observation of GRB 170208B
  100. Konus-Wind observation of GRB 170208A

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