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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"

21003 results found.

  1. IceCube-170312A: Swift-XRT observations
  2. GRB 170317A: GMG observation
  3. LIGO/Virgo G275697: Swift-XRT source 23 no longer fading
  4. LIGO/Virgo G277583: Discovery Channel Telescope Follow-Up of ATLAS17cck
  5. LIGO/Virgo G277583: ATLAS coverage and transients over the first 2 days
  6. GRB 170307A: 15 GHz upper limit from AMI
  7. LIGO/Virgo G277583: GROND follow up of ATLAS17cck
  8. LIGO/Virgo G277583: ERRATUM LV GCN 20871: TAROT Calern (TCA) observations
  9. LIGO/Virgo G277583: TAROT Calern (TCA) observations
  10. LIGO/Virgo G277583: SVOM/Mini-GWAC observations of the initial skymap
  11. LIGO/Virgo G275404: Medicina radio follow-up of near-infrared
  12. LIGO/Virgo G277583: AGILE GRID observations
  13. LIGO/Virgo G277583: AGILE MCAL observations
  14. LIGO/Virgo G270580: optical observations and classification of PS and MASTER sources
  15. LIGO/Virgo G277583: IceCube neutrino observations
  16. GRB 170311A: VLT observations
  17. INTEGRAL observation of IceCube HESE 65274589 129281
  18. LIGO/Virgo G275697: GRAWITA NOT optical observations of Swift/XRT Source 23
  19. GRB 170311A: Further GROND analysis
  20. GRB 170311A: Swift/UVOT Upper Limits
  21. SN MASTER OT J042250.16-820415.4 is the possible optical counterpart of the gravitational waves event LIGO/Virgo G274296
  22. GRB 170311A: GROND upper limits
  23. GRB 170311A: MASTER-OAFA early optical observations
  24. GRB170306A: SALT observations
  25. GRB 170306A: GROND afterglow detection
  26. LIGO/Virgo G275404: Swift-XRT observations of sources in the AGILE error region
  27. LIGO/Virgo G275697: Swift-XRT source 23 is fading
  28. LIGO/Virgo G275404 and AGL J1914+1043: INTEGRAL follow-up
  29. Swift Trigger 741528: a possible GRB
  30. GRB 170306B: Swift-XRT observations
  31. GRB 170306B: Tiled Swift observations
  32. GRB 170306A: Swift/UVOT Upper Limits
  33. GRB 170306A: GROND observations
  34. LIGO/Virgo G275697: Further Swift-XRT sources
  35. GRB 170306A: LCO Cerro Tololo observations
  36. LIGO/Virgo G275697: Liverpool Telescope classification of EM candidates
  37. LIGO/Virgo G275404: Liverpool Telescope classification of EM candidates
  38. LIGO/Virgo G275697: Further Swift-XRT sources
  39. LIGO/Virgo G275404: PIRATE Observations
  40. LIGO/Virgo G275404: Liverpool Telescope classification of EM candidates
  41. LIGO/Virgo G275697: Liverpool Telescope classification of EM candidates
  42. LIGO/Virgo G275697: Further Swift-XRT sources
  43. LIGO/Virgo G275697: MAXI/GSC observations
  44. LIGO/Virgo G275697: Additional iPTF Optical Transient Candidates
  45. LIGO/Virgo G275404: Additional iPTF Optical Transient Candidates
  46. LIGO/Virgo G275697: Further Swift-XRT sources
  47. LIGO/Virgo G275697: optical spectroscopy of Swift/XRT source 1
  48. LIGO/Virgo G268556, G270580, G274296, and G275404: Konus-Wind observations
  49. LIGO/Virgo G275697: SVOM/Mini-GWAC observations of the initial skymap
  50. LIGO/Virgo G275697: iPTF Optical Transient Candidates
  51. LIGO/Virgo G275404: iPTF Optical Transient Candidates
  52. GRB 170206B: 15 GHz upper limits from AMI
  53. LIGO/Virgo G275404: A near-infrared transient in the error circle of AGL J1914+1043
  54. LIGO/Virgo G275697: CALET Observations
  55. LIGO/Virgo G275697: MASTER automatic follow up detection
  56. LIGO/Virgo G275697: CNEOST optical observations
  57. LIGO/Virgo G274296 and G275404 : MAXI/GSC observations
  58. LIGO/Virgo G275404: Nearby galaxy observations by J-GEM collaboration
  59. LIGO/Virgo G275697: REM optical/NIR observations
  60. LIGO/Virgo G275697: Konus-Wind observations
  61. LIGO/Virgo G275404: CNEOST optical observations
  62. LIGO/Virgo G275697: Swift-XRT sources
  63. LIGO/Virgo G275404: MASTER bright PSN detected on 27 Feb from the maximum of probability of LIGO localization
  64. LIGO/Virgo G275697: AGILE MCAL Observations
  65. LIGO/Virgo G275697: INTEGRAL search for a prompt gamma-ray counterpart
  66. LIGO/VIRGO G275697: Fermi GBM Observations
  67. LIGO/Virgo G275697: IceCube neutrino observations
  68. LIGO/Virgo G274296: MASTER new PSN detected on 22 feb
  69. LIGO/Virgo G275404: REM optical/NIR observations
  70. LIGO/Virgo G275404: MASTER PSN detection from the maximal probability LIGO region
  71. LIGO/Virgo G275404: Keck spectrum of MASTER OT J105958.00-115756.5
  72. LIGO/Virgo G275404: INTEGRAL search for a prompt gamma-ray counterpart
  73. LIGO/Virgo G275404: AGILE-GRID detection of a possible gamma-ray transient
  74. LIGO/Virgo G275404: NOT Follow-up of MASTER OT
  75. LIGO/Virgo G275404: Swift-XRT sources
  76. LIGO/Virgo G275404: MASTER bright OT detection
  77. LIGO/Virgo G275404: SVOM/Mini-GWAC: Observations of initial skymap
  78. LIGO/Virgo G275404: Fermi GBM Observations
  79. LIGO/Virgo G275404: AGILE MCAL observations
  80. LIGO/Virgo G275404: MASTER Tunka OT detection
  81. LIGO/Virgo G275404: IceCube neutrino observations
  82. LIGO/Virgo G275404: MASTER automatic follow up observations
  83. LIGO/Virgo G274296: GRAWITA-Campo Imperatore observation
  84. LIGO/Virgo G274296: Liverpool Telescope classification of EM candidates
  85. LIGO/Virgo G274296: MASTER new OT
  86. LIGO/Virgo G274296: CALET Observations
  87. GRB 170222A: Swift-XRT observations
  88. GRB 170222A: Tiled Swift observations
  89. GRB 170222A: Swift ToO observations
  90. LIGO/Virgo G274296: PIRATE Observations
  91. LIGO/Virgo G274296: J-GEM optical/NIR follow-up observations
  92. LIGO/Virgo G274296: iPTF Optical Transient Candidates
  93. LIGO/Virgo G274296: Global MASTER Net PSN and QSO detection
  94. LIGO/Virgo G274296: Asiago 1.82m Optical Observations
  95. LIGO/Virgo G274296: PSN MASTER OT J042250.16-820415.4 is before maximum
  96. LIGO/Virgo G274296: IceCube neutrino observations
  97. LIGO/Virgo G274296: PESSTO classification of 9 Pan-STARRS transients
  98. LIGO/Virgo G274296: CNEOST imaging coverage and an optical transient
  99. LIGO/Virgo G274296: SWASP optical imaging coverage
  100. LIGO/Virgo G274296: Global MASTER Net two OTs detection

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