ATLAS strategy for primary vertex reconstruction during Run-2 of the LHC

21st International Conference on Computing in High Energy and Nuclear Physics

物理学;计算机科学

Borissov, G.^1 ; Casper, D.^2 ; Grimm, K.^1 ; Pagan Griso, S.^3 ; Egholm Pedersen, L.^4 ; Prokofiev, K.^5 ; Rudolph, M.^6 ; Wharton, A.^1

Lancaster University, United Kingdom^1

University of California, Irvine, United States^2

Lawrence Berkeley National Laboratory, University of California, Berkeley, United States^3

Niels Bohr Institute (NBI), University of Copenhagen, Denmark^4

Hong Kong University of Science and Technology, Hong Kong^5

University of Toronto, Canada^6

关键词: Essential elements;    Event reconstruction;    Image reconstruction techniques;    Iterative approach;    Performance study;    Proton proton collisions;    Simultaneous collisions;    Vertex reconstruction;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/664/7/072041/pdf
DOI  :  10.1088/1742-6596/664/7/072041

学科分类：计算机科学（综合）

来源: IOP

【 摘 要 】

The reconstruction of vertices corresponding to proton-proton collisions in ATLAS is an essential element of event reconstruction used in many performance studies and physics analyses. During Run-1 of the LHC, ATLAS has employed an iterative approach to vertex finding. In order to improve the flexibility of the algorithm and ensure continued performance for very high numbers of simultaneous collisions in Run-2 of the LHC and beyond, a new approach to seeding vertex finding has been developed inspired by image reconstruction techniques. This note provides a brief outline of how reconstructed tracks are used to create an image of likely vertex collisions in an event, describes the implementation in the ATLAS software, and presents some preliminary results of the performance of the algorithm in simulation approximating early Run-2 conditions.