The neural network first-level hardware track trigger of the Belle II experiment

IF 1.5 3区 物理与天体物理 Q3 INSTRUMENTS & INSTRUMENTATION
S. Bähr , H. Bae , J. Becker , M. Bertemes , M. Campajola , T. Ferber , T. Forsthofer , S. Hiesl , G. Inguglia , Y. Iwasaki , T. Jülg , C. Kiesling , A.C. Knoll , T. Koga , Y.-T. Lai , A. Lenz , Y. Liu , F. Meggendorfer , H. Nakazawa , M. Neu , J. Yin
{"title":"The neural network first-level hardware track trigger of the Belle II experiment","authors":"S. Bähr ,&nbsp;H. Bae ,&nbsp;J. Becker ,&nbsp;M. Bertemes ,&nbsp;M. Campajola ,&nbsp;T. Ferber ,&nbsp;T. Forsthofer ,&nbsp;S. Hiesl ,&nbsp;G. Inguglia ,&nbsp;Y. Iwasaki ,&nbsp;T. Jülg ,&nbsp;C. Kiesling ,&nbsp;A.C. Knoll ,&nbsp;T. Koga ,&nbsp;Y.-T. Lai ,&nbsp;A. Lenz ,&nbsp;Y. Liu ,&nbsp;F. Meggendorfer ,&nbsp;H. Nakazawa ,&nbsp;M. Neu ,&nbsp;J. Yin","doi":"10.1016/j.nima.2025.170279","DOIUrl":null,"url":null,"abstract":"<div><div>We describe the principles and performance of the first-level (“L1”) hardware track trigger of Belle II<!--> <!-->, which uses the information of Belle II<!--> <!-->’s Central Drift Chamber (“CDC”) and provides three-dimensional track candidates based on neural networks. The inputs to the networks are “2D” track candidates in the plane transverse to the electron–positron beams, obtained via Hough transforms, and selected information from the stereo layers of the CDC. The networks then provide estimates for the origin of the track candidates in direction of the colliding beams (“<span><math><mi>z</mi></math></span>-vertex”), as well as their polar emission angles <span><math><mi>θ</mi></math></span>. Using a suitable cut <span><math><mi>d</mi></math></span> on the <span><math><mi>z</mi></math></span>-vertices of the “neural” tracks allows us to identify events coming from the collision region (<span><math><mrow><mi>z</mi><mo>≈</mo><mn>0</mn></mrow></math></span>), and to suppress the overwhelming background from outside. Requiring <span><math><mrow><mrow><mo>|</mo><mi>z</mi><mo>|</mo></mrow><mo>&lt;</mo><mi>d</mi></mrow></math></span> for at least one neural track in an event with two or more 2D candidates will set an L1 track trigger. The networks also enable a minimum bias trigger, requiring a single 2D track candidate validated by a neural track with a momentum larger than 0.7 GeV in addition to the <span><math><mrow><mo>|</mo><mi>z</mi><mo>|</mo></mrow></math></span> condition. We also sketch our concepts for upgrading the neural trigger in view of rising instantaneous luminosities, accompanied by increasing backgrounds.</div></div>","PeriodicalId":19359,"journal":{"name":"Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment","volume":"1073 ","pages":"Article 170279"},"PeriodicalIF":1.5000,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment","FirstCategoryId":"101","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0168900225000804","RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"INSTRUMENTS & INSTRUMENTATION","Score":null,"Total":0}
引用次数: 0

Abstract

We describe the principles and performance of the first-level (“L1”) hardware track trigger of Belle II , which uses the information of Belle II ’s Central Drift Chamber (“CDC”) and provides three-dimensional track candidates based on neural networks. The inputs to the networks are “2D” track candidates in the plane transverse to the electron–positron beams, obtained via Hough transforms, and selected information from the stereo layers of the CDC. The networks then provide estimates for the origin of the track candidates in direction of the colliding beams (“z-vertex”), as well as their polar emission angles θ. Using a suitable cut d on the z-vertices of the “neural” tracks allows us to identify events coming from the collision region (z0), and to suppress the overwhelming background from outside. Requiring |z|<d for at least one neural track in an event with two or more 2D candidates will set an L1 track trigger. The networks also enable a minimum bias trigger, requiring a single 2D track candidate validated by a neural track with a momentum larger than 0.7 GeV in addition to the |z| condition. We also sketch our concepts for upgrading the neural trigger in view of rising instantaneous luminosities, accompanied by increasing backgrounds.
求助全文
约1分钟内获得全文 求助全文
来源期刊
CiteScore
3.20
自引率
21.40%
发文量
787
审稿时长
1 months
期刊介绍: Section A of Nuclear Instruments and Methods in Physics Research publishes papers on design, manufacturing and performance of scientific instruments with an emphasis on large scale facilities. This includes the development of particle accelerators, ion sources, beam transport systems and target arrangements as well as the use of secondary phenomena such as synchrotron radiation and free electron lasers. It also includes all types of instrumentation for the detection and spectrometry of radiations from high energy processes and nuclear decays, as well as instrumentation for experiments at nuclear reactors. Specialized electronics for nuclear and other types of spectrometry as well as computerization of measurements and control systems in this area also find their place in the A section. Theoretical as well as experimental papers are accepted.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信