An artificial neural network based b jet identification algorithm at the CDF experiment

作者:Freeman J; Ketchum W; Lewis J D; Poprocki S; Pronko A; Rusu V; Wittich P*
来源:Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment , 2012, 663(1): 37-47.
DOI:10.1016/j.nima.2011.10.024

摘要

We present the development and validation of a new multivariate b jet identification algorithm ("b tagger") used at the CDF experiment at the Fermilab Tevatron. At collider experiments, b taggers allow one to distinguish particle jets containing B hadrons from other jets. Employing feed-forward neural network architectures, this tagger is unique in its emphasis on using information from individual tracks. This tagger not only contains the usual advantages of a multivariate technique such as maximal use of information in a jet and tunable purity/efficiency operating points, but is also capable of evaluating jets with only a single track. To demonstrate the effectiveness of the tagger, we employ a novel method wherein we calculate the false tag rate and tag efficiency as a function of the placement of a lower threshold on a jet's neural network output value in Z+1 jet and t (t) over bar candidate samples, rich in light-flavor and b jets, respectively.

  • 出版日期2012-1-21