G. Benito Diaz¹ , J. Blázquez¹ , J.C. Sáez¹ , J. Quiñones¹

¹Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Madrid, Spain

Abstract:

Section B of Article IV of the CTBT defines the IMS, which is responsible for verifying compliance with the Treaty. Data generated by the IMS and processed by the IDC are often fragmented because some data is below the detection limit. This implies that they need to be reconstructed using autoregressive models for more advanced statistical analysis. The use of advanced statistic allows monitoring the evolution of activity concentration in a more accurate way before, during and after a radiological event. In addition, the statistical characterization of the time series serves as an indication of a possible malfunction in the measuring station, which allows us to anticipate the preventive actions without losing quality in the operation of the network and decrease maintenance costs. This methodology has been carried out for the 133Xe radionuclide registered at the RN38 station (Takasaki, Japan) from the 1st of August to the 31st of October, 2016. Preliminary results of the time evolution of the signal made is possible to establish the baseline for 133Xe, to detect the significant high concentration events and to obtain time trends that could be related to the data quality and equipment output.