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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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

43933 results found.

  1. GRB 170307A: Fermi GBM observation
  2. LIGO/Virgo G275404 and AGL J1914+1043: INTEGRAL follow-up
  3. LIGO/Virgo G275697: Updated localization from LIGO data
  4. Swift Trigger 741528: a possible GRB
  5. Konus-Wind observation of GRB 170306B
  6. GRB 170306B: Swift-XRT observations
  7. GRB 170306A, Swift-BAT refined analysis
  8. GRB 170306A: Swift-XRT refined Analysis
  9. GRB 170306B: Fermi GBM detection
  10. GRB 170306B: Fermi-LAT detection
  11. GRB 170306B: Tiled Swift observations
  12. IPN Triangulation of GRB 170305A (short)
  13. LIGO/Virgo G275697: Further Swift-XRT sources
  14. GRB 170306A: LCO Cerro Tololo observations
  15. GRB 170306A: Swift detection of a burst
  16. GRB170305A: Fermi GBM detection
  17. LIGO/Virgo G275697: Liverpool Telescope classification of EM candidates
  18. LIGO/Virgo G275404: Liverpool Telescope classification of EM candidates
  19. GRB 170304A: Fermi GBM observation
  20. LIGO/Virgo G275697: Further Swift-XRT sources
  21. LIGO/Virgo G275404: HAWC follow-up
  22. LIGO/Virgo G275404: PIRATE Observations
  23. LIGO/Virgo G275404: Liverpool Telescope classification of EM candidates
  24. LIGO/Virgo G275697: Liverpool Telescope classification of EM candidates
  25. LIGO/Virgo G275697: Further Swift-XRT sources
  26. Konus-Wind observation of GRB 170228A
  27. Fermi GBM trigger 510207699/170303182 is not a GRB
  28. LIGO/Virgo G275697: MAXI/GSC observations
  29. GRB 170228B CALET Gamma-Ray Burst Monitor detection
  30. LIGO/Virgo G275697: Additional iPTF Optical Transient Candidates
  31. LIGO/Virgo G275404: Additional iPTF Optical Transient Candidates
  32. LIGO/Virgo G275404: Nearby Galaxies in the Localization Volume
  33. LIGO/Virgo G275697: Further Swift-XRT sources
  34. LIGO/Virgo G275697: Fermi GBM Upper Limits
  35. LIGO/Virgo G275697: AstroSat CZTI upper limits
  36. LIGO/Virgo G275697: optical spectroscopy of Swift/XRT source 1
  37. LIGO/Virgo G268556, G270580, G274296, and G275404: Konus-Wind observations
  38. LIGO/Virgo G275697: SVOM/Mini-GWAC observations of the initial skymap
  39. GRB 170228B: POLAR Observation
  40. LIGO/Virgo G275697: iPTF Optical Transient Candidates
  41. LIGO/Virgo G275404: iPTF Optical Transient Candidates
  42. LIGO/Virgo G275404: Fermi GBM Upper Limits
  43. GRB 170228A: AstroSat CZTI detection
  44. GRB 170206B: 15 GHz upper limits from AMI
  45. GRB 170228A: Fermi GBM observation
  46. GRB 170228A: Fermi-LAT detection
  47. LIGO/Virgo G275404: A near-infrared transient in the error circle of AGL J1914+1043
  48. LIGO/Virgo G275697: CALET Observations
  49. LIGO/Virgo G275697: MASTER automatic follow up detection
  50. LIGO/Virgo G275697: CNEOST optical observations
  51. LIGO/Virgo G274296 and G275404 : MAXI/GSC observations
  52. LIGO/Virgo G275404: Nearby Galaxies in the Localization Region
  53. LIGO/Virgo G275697: Fermi-LAT search for a high-energy gamma-ray counterpart
  54. LIGO/Virgo G275697: REM optical/NIR observations
  55. LIGO/Virgo G275697: Konus-Wind observations
  56. LIGO/Virgo G275404: CNEOST optical observations
  57. LIGO/Virgo G275697: Swift-XRT sources
  58. LIGO/Virgo G275697: Swift/BAT data search
  59. LIGO/Virgo G275404: MASTER bright PSN detected on 27 Feb from the maximum of probability of LIGO localization
  60. LIGO/Virgo G275697: AGILE-GRID preliminary analysis
  61. LIGO/Virgo G275697: AGILE MCAL Observations
  62. LIGO/Virgo G275697: INTEGRAL search for a prompt gamma-ray counterpart
  63. LIGO/VIRGO G275697: Fermi GBM Observations
  64. LIGO/Virgo G275404: AstroSat CZTI upper limits
  65. LIGO/Virgo G275697 ANTARES search
  66. LIGO/Virgo G275697: IceCube neutrino observations
  67. LIGO/Virgo G275697: Identification of a GW CBC Candidate
  68. LIGO/Virgo G275404: Keck LRIS classification of MASTER PSN candidate
  69. LIGO/Virgo G274296: MASTER new PSN detected on 22 feb
  70. LIGO/Virgo G275404: REM optical/NIR observations
  71. LIGO/Virgo G275404: MASTER PSN detection from the maximal probability LIGO region
  72. LIGO/Virgo G275404: Keck spectrum of MASTER OT J105958.00-115756.5
  73. LIGO/Virgo G275404: Fermi-LAT search for a high-energy gamma-ray counterpart
  74. LIGO/Virgo G275404: INTEGRAL search for a prompt gamma-ray counterpart
  75. LIGO/Virgo G275404: AGILE-GRID detection of a possible gamma-ray transient
  76. LIGO/Virgo G275404: NOT Follow-up of MASTER OT
  77. LIGO/Virgo G275404: Swift-XRT sources
  78. LIGO/Virgo G275404 ANTARES search
  79. LIGO/Virgo G275404: Follow-up of MASTER OT J173532.70+103810.5
  80. GRB 170222A: CALET Gamma-Ray Burst Monitor detection
  81. LIGO/Virgo G275404: MASTER bright OT detection
  82. LIGO/Virgo G274296: P200 classification of EM candidates
  83. LIGO/Virgo G275404: Swift/BAT data search
  84. LIGO/Virgo G275404: SVOM/Mini-GWAC: Observations of initial skymap
  85. LIGO/Virgo G274296: Swift/BAT data search
  86. LIGO/Virgo G275404: AGILE-GRID preliminary analysis
  87. LIGO/Virgo G275404: Fermi GBM Observations
  88. LIGO/Virgo G275404: AGILE MCAL observations
  89. LIGO/Virgo G275404: MASTER Tunka OT detection
  90. LIGO/Virgo G275404: IceCube neutrino observations
  91. LIGO/Virgo G275404: Identification of a GW CBC Candidate
  92. LIGO/Virgo G275404: MASTER automatic follow up observations
  93. LIGO/Virgo G274296: GRAWITA-Campo Imperatore observation
  94. LIGO/Virgo G274296: Liverpool Telescope classification of EM candidates
  95. GRB 170220A: POLAR Observation
  96. LIGO/Virgo G274296: MASTER new OT
  97. Konus-Wind observation of GRB 170222A
  98. LIGO/Virgo G274296: CALET Observations
  99. GRB 170222A: Swift-XRT observations
  100. GRB 170222A: Fermi GBM observation

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