Results of LLNL investigation of NYCT data sets Metadata

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  • Main Title Results of LLNL investigation of NYCT data sets


  • Author: Sale, K
    Creator Type: Personal
  • Author: Harrison, M
    Creator Type: Personal
  • Author: Guo, M
    Creator Type: Personal
  • Author: Groza, M
    Creator Type: Personal


  • Sponsor: United States. Department of Energy.
    Contributor Type: Organization


  • Name: Lawrence Livermore National Laboratory
    Place of Publication: Livermore, California
    Additional Info: Lawrence Livermore National Laboratory (LLNL), Livermore, CA


  • Creation: 2007-08-01


  • English


  • Content Description: Upon examination we have concluded that none of the alarms indicate the presence of a real threat. A brief history and results from our examination of the NYCT ASP occupancy data sets dated from 2007-05-14 19:11:07 to 2007-06-20 15:46:15 are presented in this letter report. When the ASP data collection campaign at NYCT was completed, rather than being shut down, the Canberra ASP annunciator box was unplugged leaving the data acquisition system running. By the time it was discovered that the ASP was still acquiring data about 15,000 occupancies had been recorded. Among these were about 500 alarms (classified by the ASP analysis system as either Threat Alarms or Suspect Alarms). At your request, these alarms have been investigated. Our conclusion is that none of the alarm data sets indicate the presence of a real threat (within statistics). The data sets (ICD1 and ICD2 files with concurrent JPEG pictures) were delivered to LLNL on a removable hard drive labeled FOUO. The contents of the data disk amounted to 53.39 GB of data requiring over two days for the standard LLNL virus checking software to scan before work could really get started. Our first step was to walk through the directory structure of the disk and create a database of occupancies. For each occupancy, the database was populated with the occupancy date and time, occupancy number, file path to the ICD1 data and the alarm ('No Alarm', 'Suspect Alarm' or 'Threat Alarm') from the ICD2 file along with some other incidental data. In an attempt to get a global understanding of what was going on, we investigated the occupancy information. The occupancy date/time and alarm type were binned into one-hour counts. These data are shown in Figures 1 and 2.
  • Physical Description: PDF-file: 13 pages; size: 0.5 Mbytes


  • Keyword: Lawrence Livermore National Laboratory
  • Keyword: Statistics
  • STI Subject Categories: 22 General Studies Of Nuclear Reactors
  • Keyword: Data Acquisition Systems
  • STI Subject Categories: 73 Nuclear Physics And Radiation Physics
  • STI Subject Categories: 45 Military Technology, Weaponry, And National Defense


  • Name: Office of Scientific & Technical Information Technical Reports
    Code: OSTI


  • Name: UNT Libraries Government Documents Department
    Code: UNTGD

Resource Type

  • Report


  • Text


  • Report No.: UCRL-TR-233410
  • Grant Number: W-7405-ENG-48
  • DOI: 10.2172/921765
  • Office of Scientific & Technical Information Report Number: 921765
  • Archival Resource Key: ark:/67531/metadc901522