The COMPASS Experiment at CERN

Abstract

The COMPASS experiment makes use of the CERN SPS high-intensitymuon and hadron beams for the investigation of the nucleon spin structure and the spectroscopy of hadrons. One or more outgoing particles are detected in coincidence with the incoming muon or hadron. A large polarized target inside a superconducting solenoid is used for the measurements with the muon beam. Outgoing particles are detected by a two-stage, large angle and large momentum range spectrometer. The setup is built using several types of tracking detectors, according to the expected incident rate, required space resolution and the solid angle to be covered. Particle identification is achieved using a RICH counter and both hadron and electromagnetic calorimeters. The setup has been successfully operated from 2002 onwards using a muon beam. Data with a hadron beam were also collected in 2004. This article describes the main features and performances of the spectrometer in 2004; a short summary of the 2006 upgrade is also given.

84 papes, 74 figures

References in corpus (6)

• High-Energy-Physics Event Generation with PYTHIA 6.1
• First Measurement of the Transverse Spin Asymmetries of the Deuteron in Semi-Inclusive Deep Inelastic Scattering
• Gluon polarization in the nucleon from quasi-real photoproduction of high-pT hadron pairs
• Measurement of the Spin Structure of the Deuteron in the DIS Region
• Implementation of the Dead-Time Free F1 TDC in the COMPASS Detector Readout
• Search for the Phi(1860) Pentaquark at COMPASS

Cited by in corpus (160)

• The Spin Structure of the Nucleon
• Collins and Sivers asymmetries for pions and kaons in muon-deuteron DIS
• The Status of Glueballs
• A new measurement of the Collins and Sivers asymmetries on a transversely polarised deuteron target
• Parton Fragmentation Functions
• Measuring the leading hadronic contribution to the muon g-2 via $\mu e$ scattering
• Discovering New Light States at Neutrino Experiments
• Measurement of the Collins and Sivers asymmetries on transversely polarised protons
• Experimental investigation of transverse spin asymmetries in muon-p SIDIS processes: Sivers asymmetries
• Quark helicity distributions from longitudinal spin asymmetries in muon-proton and muon-deuteron scattering
• Observation of a J^PC = 1-+ exotic resonance in diffractive dissociation of 190 GeV/c pi- into pi- pi- pi+
• The Spin Structure Function $g_1^{\mathrm{p}}$ of the Proton and a Test of the Bjorken Sum Rule
• Experimental investigation of transverse spin asymmetries in muon-p SIDIS processes: Collins asymmetries
• First measurement of transverse-spin-dependent azimuthal asymmetries in the Drell-Yan process
• Collins and Sivers asymmetries in muonproduction of pions and kaons off transversely polarised proton
• Flavor-specific scalar mediators
• The Leptonic Higgs Portal
• Transverse spin effects in hadron-pair production from semi-inclusive deep inelastic scattering
• The Polarised Valence Quark Distribution from semi-inclusive DIS
• Probing Muonic Forces and Dark Matter at Kaon Factories
• Three-body Unitarity with Isobars Revisited
• A Novel Generic Framework for Track Fitting in Complex Detector Systems
• Flavour Separation of Helicity Distributions from Deep Inelastic Muon-Deuteron Scattering
• A high-statistics measurement of transverse spin effects in dihadron production from muon-proton semi-inclusive deep-inelastic scattering
• The COMPASS Setup for Physics with Hadron Beams
• Odd and Even Partial Waves of $\eta {\pi }^{-}$ and ${\eta }^{\prime }{\pi }^{-}$ in ${\pi }^{-}p\to {\eta }^{(\prime )}{\pi }^{-}p$ at $191\text{GeV}/c$
• Light isovector resonances in ${\pi }^{-}p\to {\pi }^{-}{\pi }^{-}{\pi }^{+}p$ at 190 GeV/$c$
• Observation of a new narrow axial-vector meson $a_1(1420)$
• Measurement of azimuthal hadron asymmetries in semi-inclusive deep inelastic scattering off unpolarised nucleons
• Extracting Electric Polarizabilities from Lattice QCD
• Leading and Next-to-Leading Order Gluon Polarisation in the Nucleon and Longitudinal Double Spin Asymmetries from Open Charm Muoproduction
• Hadron Transverse Momentum Distributions in Muon Deep Inelastic Scattering at 160 GeV/$c$
• Leading-Order Determination of the Gluon Polarization from high-$p_T$ Hadron Electroproduction
• Transverse-momentum-dependent Multiplicities of Charged Hadrons in Muon-Deuteron Deep Inelastic Scattering
• Transverse Spin Structure of the Nucleon through Target Single Spin Asymmetry in Semi-Inclusive Deep-Inelastic $(e,e^{\prime }{\pi }^{\pm })$ Reaction at Jefferson Lab
• Resonance Production and $\pi \pi$ S-wave in ${\pi }^{-}+p\to {\pi }^{-}{\pi }^{-}{\pi }^{+}+p_{recoil}$ at 190 GeV/c
• Leading order determination of the gluon polarisation from DIS events with high-p_T hadron pairs
• Light-Meson Spectroscopy with COMPASS
• Sivers asymmetry extracted in SIDIS at the hard scale of the Drell-Yan process at COMPASS
• Final COMPASS results on the deuteron spin-dependent structure function $g_1^{\mathrm{d}}$ and the Bjorken sum rule
• Multiplicities of charged pions and unidentified charged hadrons from deep-inelastic scattering of muons off an isoscalar target
• Measurement of the charged-pion polarisability
• Transverse Extension of Partons in the Proton probed by Deeply Virtual Compton Scattering
• Multiplicities of charged kaons from deep-inelastic muon scattering off an isoscalar target
• Measurement of the Longitudinal Spin Transfer to Lambda and Anti-Lambda Hyperons in Polarised Muon DIS
• First lattice QCD study of the gluonic structure of light nuclei
• Gluon Polarisation in the Nucleon and Longitudinal Double Spin Asymmetries from Open Charm Muoproduction
• Conceptual design of the Spin Physics Detector
• Prospects in the search for a new light $Z^{\prime }$ boson with the NA64$\mu$ experiment at the CERN SPS
• Electric polarizability of neutral hadrons from dynamical lattice QCD ensembles
• Model Selection for Pion Photoproduction
• Triangle Singularity as the Origin of the $a_1(1420)$
• New pixelized Micromegas detector with low discharge rate for the COMPASS experiment
• The next generation of laser spectroscopy experiments using light muonic atoms
• Search for exclusive photoproduction of Z${}_c^{\pm }$(3900) at COMPASS
• First measurement of the Sivers asymmetry for gluons from SIDIS data
• Azimuthal asymmetries of charged hadrons produced by high-energy muons scattered off longitudinally polarised deuterons
• Status of the MUonE experiment
• Search for muoproduction of $X(3872)$ at COMPASS and indication of a new state $\tilde{X}(3872)$
• Transverse target spin asymmetries in exclusive ${\rho }^0$ muoproduction
• Longitudinal double-spin asymmetry $A_1^{\mathrm{p}}$ and spin-dependent structure function $g_1^{\mathrm{p}}$ of the proton at small values of $x$ and $Q^2$
• The polarizability of the pion: no conflict between dispersion theory and chiral perturbation theory
• Double spin asymmetry in exclusive rho^0 muoproduction at COMPASS
• Measurement of the cross section for hard exclusive ${\pi }^0$ leptoproduction
• The MPGD-Based Photon Detectors for the upgrade of COMPASS RICH-1 and beyond
• The exotic meson ${\pi }_1(1600)$ with $J^{PC}=1^{-+}$ and its decay into $\rho (770)\pi$
• Measurement of $P_T$-weighted Sivers asymmetries in leptoproduction of hadrons
• Exclusive rho^0 muoproduction on transversely polarised protons and deuterons
• Azimuthal asymmetries of charged hadrons produced in high-energy muon scattering off longitudinally polarised deuterons
• First Measurement of Chiral Dynamics in π^- γ-> π^- π^- π^+
• ${\Lambda }_c^{+}(2940)$ photoproduction off the neutron
• Six "beyond Collins and Sivers" transverse spin asymmetries at COMPASS
• Chiral corrections to ${\pi }^{-}\gamma \to 3\pi$ processes at low energies
• Performance of Multiplexed XY Resistive Micromegas detectors in a high intensity beam
• Measurement of radiative widths of $a_2(1320)$ and ${\pi }_2(1670)$
• The Thick Gas Electron Multiplier and its derivatives: physics, technologies and applications
• K${}^{-}$ over K${}^{+}$ multiplicity ratio for kaons produced in DIS with a large fraction of the virtual-photon energy
• A Very High Momentum Particle Identification Detector
• Interplay among transversity induced asymmetries in hadron leptoproduction
• A study of muon-electron elastic scattering in a test beam
• Final state interactions and hadron quenching in cold nuclear matter
• Semi-inclusive lepto-production of hidden-charm exotic hadrons
• A Large Ungated TPC with GEM Amplification
• New pixelized Micromegas detector for the COMPASS experiment
• Particle Identification at FCC-ee
• Transverse spin dependent azimuthal asymmetries at COMPASS
• Pattern recognition and PID for COMPASS RICH-1
• Compton Scattering off Pions and Electromagnetic Polarizabilities
• Exclusive $\omega$ meson muoproduction on transversely polarised protons
• Beam impact tests of a prototype target for the Beam Dump Facility at CERN: experimental setup and preliminary analysis of the online results
• Numerical estimation of discharge probability in GEM-based detectors
• Exploring Baryon Resonances with Transition Generalized Parton Distributions: Status and Perspectives
• Study of Σ(1385) and Ξ(1321) hyperon and antihyperon production in deep inelastic muon scattering
• Electromagnetic and gravitational form factors in simulated QED and Yukawa model
• Radiative Corrections to High Energy Lepton Bremsstrahlung on Heavy Nuclei
• Measurement of the Cross Section for High-p_T Hadron Production in Scattering of 160 GeV/c Muons off Nucleons
• Collins and Sivers transverse-spin asymmetries in inclusive muoproduction of ${\rho }^0$ mesons
• Azimuthal asymmetries in the unpolarized SIDIS cross section at COMPASS
• The Fast Read-out System for the MAPMTs of COMPASS RICH-1
• Precision spectroscopy with COMPASS and the observation of a new iso-vector resonance
• Photoproduction of $a_2(1320)$ in a Regge model
• Measurement of neutron and proton analyzing powers on $C$, $CH$, $C{H}_2$ and $Cu$ targets in the momentum region 3-4.2 GeV/c
• Spin alignment and violation of the OZI rule in exclusive $\omega$ and $\varphi$ production in pp collisions
• The production of neutral $N^{\ast }(11052)$ resonance with hidden beauty from ${\pi }^{-}p$ scattering
• Large-Area Sandwich Veto Detector with WLS Fibre Readout for Hadron Spectroscopy at COMPASS
• Transversity distributions from difference asymmetries in semi-inclusive DIS
• D* and D Meson Production in Muon Nucleon Interactions at 160 GeV/c
• Extraction of characteristic constants in QCD with perturbative and nonperturbative methods
• Phenomenological model of multiphoto-production of charged pion pairs on the proton
• The high voltage system with pressure and temperature corrections for the novel MPGD-based photon detectors of COMPASS RICH-1
• Antiproton over proton and K${}^{-}$ over K${}^{+}$ multiplicity ratios at high $z$ in DIS
• Deep-Inelastic Scattering at TeV Energies with LHC Muons
• Control Systems: an Application to a High Energy Physics Experiment (COMPASS)
• Quadrupole polarizabilities of the pion in the Nambu--Jona-Lasinio model
• Development and Performance Verification of the GANDALF High-Resolution Transient Recorder System
• FPGA based data acquisition system for COMPASS experiment
• Polarized nuclear target based on parahydrogen induced polarization
• Concept for an Electron Ion Collider (EIC) detector built around the BaBar solenoid
• Multiple hit reconstruction in large area multiplexed detectors
• Direct measurements of the properties of Thick-GEM reflective photocathodes
• Implementation of mean-timing and subsequent logic functions on an FPGA
• Axial anomaly and the interplay of quark loops with pseudoscalar and vector mesons in the gamma* --> pi+ pi0 pi- process
• Next Frontiers in Particle Physics Detectors: INSTR2020 Summary and a Look into the Future
• MPGD-based photon detectors for the upgrade of COMPASS RICH-1 and beyond
• First Results of the PixelGEM Central Tracking System for COMPASS
• On duality of Drell-Yan and J/psi production processes
• Searching and identifying leptoquarks through low-energy polarized scattering processes $e^{-}p\to e^{-}{\Lambda }_c$
• Highlights from the COMPASS experiment at CERN -- Hadron spectroscopy and excitations
• Double $J/\psi$ production in pion-nucleon scattering at COMPASS
• R&D Proposal, RD51 Extension Beyond 2018
• Micro-Pattern Gas Detectors for Charged-Particle Tracking and Muon Detection
• Test for exotic isoscalar resonance dominating $D^0\to {\pi }^{+}{\pi }^{-}{\pi }^0$ decays
• A Large-Scale FPGA-Based Trigger and Dead-Time Free DAQ System for the Kaos Spectrometer at MAMI
• ΔG/G results from the COMPASS experiment for Q^2 > 1 GeV^2, using high p_T hadrons
• Radiative corrections to neutral pion-pair production
• Measurement of the longitudinal spin structure of the proton by COMPASS
• Transverse Spin Structure of the Nucleon from COMPASS
• COMPASS Results on Transverse Single-Spin Asymmetries
• Odd and Even Partial Waves of ηπ^- and η'π^- in 191 GeV/c π^-p
• Meson spectroscopy with COMPASS
• A Prototype Scalable Readout System for Micro-pattern Gas Detectors
• Hadron Spectroscopy with COMPASS at CERN
• Gluon Polarisation Measurements @ COMPASS
• Baryon Spectroscopy at COMPASS
• Tests of Three-Flavor Chiral Perturbation Theory
• Hard Quasi-real Photo-production of Charged Hadrons at COMPASS energies
• Search for muoproduction of the X(3872) at COMPASS
• Transverse Spin Physics at COMPASS
• Work on the interplay among $h^{+}$, $h^{-}$ and hadron pair transverse spin asymmetries in SIDIS
• Search for Axion Like Particles produced via the Primakoff process at COMPASS
• COMPASS Hadron Spectroscopy -- Final states involving neutrals and kaons
• Diffractive Dissociation of 190 GeV/c ${\pi }^{-}$ into ${\pi }^{-}{\pi }^{+}{\pi }^{-}$ Final States at COMPASS
• Making the $\mu$OST of the Muon Collider
• 2-D straw detectors with high rate capability
• The MPGD-Based Photon Detectors for the upgrade of COMPASS RICH-1
• Transverse Spin Effects at COMPASS
• Pion Polarizability in the NJL model and Possibilities of its Experimental Studies in Coulomb Nuclear Scattering
• Transversity Measurements at COMPASS
• Spin Physics at COMPASS
• SU(3) Gauge Symmetry: An Experimental Review of Diffractive Physics in e+p, p+p, p+A, and A+A Collision Systems