| Article | |
| Report number | arXiv:1412.2594 |
| Title | Hadron Physics at the COMPASS Experiment |
| Author(s) | Krinner, Fabian (Munich, Tech. U.) |
| Collaboration | for the COMPASS collaboration |
| Publication | 2015-05-29 |
| Imprint | 08 Dec 2014 |
| Number of pages | 7 |
| Note | Comments: Proceedings of the 3rd International Conference on New Frontiers in Physics from 28 July 2014 to 6 August 2014 7 pages, 10 figures Proceedings of the 3rd International Conference on New Frontiers in Physics from 28 July 2014 to 6 August 2014 7 pages, 10 figures |
| In: | EPJ Web Conf. 95 (2015) 04033 |
| In: | 3rd International Conference on New Frontiers in Physics, Kolymbari, Greece, 28 Jul - 06 Aug 2014, pp.04033 |
| DOI | 10.1051/epjconf/20159504033 |
| Subject category | Particle Physics - Experiment |
| Accelerator/Facility, Experiment | CERN SPS ; COMPASS NA58 |
| Abstract | Quantum Chromodynamics (QCD), the theory of strong interactions, in principle describes the interaction of quark and gluon fields. However, due to the self-coupling of the gluons, quarks and gluons are confined into hadrons and cannot exist as free particles. The quantitative understanding of this confinement phenomenon, which is responsible for about 98\% of the mass of the visible universe, is one of the major open questions in particle physics. The measurement of the excitation spectrum of hadrons and of their properties gives valuable input to theory and phenomenology. In the Constituent Quark Model (CQM) two types of hadrons exist: mesons, made out of a quark and an antiquark, and baryons, which consist of three quarks. But more advanced QCD-inspired models and Lattice QCD calculations predict the existence of hadrons with exotic properties interpreted as excited glue (hybrids) or even pure gluonic bound states (glueballs). The COMPASS experiment at the CERN Super Proton Synchrotron has acquired large data sets, which allow to study light-quark meson and baryon spectra in unprecedented detail. The presented overview of the first results from this data set focuses in particular on the light meson sector and presents a detailed analysis of three-pion final states. A new $J^{PC} = 1^{++}$ state, the $a_1(1420)$, is observed with a mass and width in the ranges $m = 1412-1422\,\mathrm{MeV}/c^2$ and $\Gamma = 130-150\,\mathrm{MeV}/c^2$. |
| Copyright/License | arXiv nonexclusive-distrib. 1.0 publication: © 2015-2024 The Author(s) (License: CC-BY-4.0) |
Corresponding record in: Inspire
Record created 2014-12-10, last modified 2023-03-14
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