Related papers: Hadron Spectroscopy with COMPASS
We propose a new fixed-target experiment for the study of electromagnetic and hard probes of the Quark-Gluon Plasma (QGP) in heavy-ion collisions at the CERN SPS. The experiment aims at performing measurements of the dimuon spectrum from…
Performances of the Very Forward Proton Spectrometer (VFPS) of the H1 detector at HERA using data collected during the 2006/2007 running period are discussed, including the description of acceptance, reconstruction of proton energy loss and…
The diffractive dissociation of virtual photons, gamma*p -> Xp, has been studied with the H1 and ZEUS detectors at HERA using various complementary techniques. Events have been selected by direct tagging of the outgoing proton or by…
New results on single spin asymmetries of identified charged pion and kaon pairs produced in deep-inelastic scattering of muons on a transversely polarized 6LiD target are presented. The data were taken in the years 2003 and 2004 with the…
New Micromegas (Micro-mesh gaseous detectors) are being developed in view of the future physics projects planned by the COMPASS collaboration at CERN. Several major upgrades compared to present detectors are being studied: detectors…
Measuring single spin asymmetries in semi-inclusive deep-inelastic scattering (SIDIS) on a transversely polarized target gives a handle to investigate the transversity distribution and transverse momentum dependent distribution functions.…
Photo-production of excited mesons in the 1-2 GeV mass range decaying via multi-pion or multi-kaon emission has been investigated at the TJNAF\thanks{This work was supported by the U.S. Department of Energy and The U.S. National Science…
The transversity parton distribution remains a poorly known cornerstone in the nucleon spin structure. While the Collins effect in spin asymmetries in Semi-Inclusive DIS (SIDIS) is one crucial tool to address the transversity function, the…
Since 2005, measurements of Collins and Sivers asymmetries from the HERMES and COMPASS experiments have allowed to assess that the transversity and the Sivers PDFs are different from zero and measurable in semi-inclusive DIS on transversely…
In 2016 and 2017 COMPASS has collected a considerable amount of deep inelastic scattering events with a 160 GeV/c muon beam and a liquid hydrogen target. An analysis of 4 % of these data has allowed to extract preliminary results on the…
New experiments in polarised deep inelastic scattering will mainly concentrate on the measurement of semi-inclusive asymmetries. Especially, the upgraded HERMES experiment at DESY and the newly build COMPASS experiment at CERN will…
Recent results on spectroscopy and the measurement of hadronic final states in ep collisions from the H1 and ZEUS collaborations are presented using data sets with an integrated luminosity between 44 and 121 pb^-1 collected during the HERA…
One of the remaining challenges within the standard model is to gain a good understanding of QCD in the non-perturbative regime. One key step toward this aim is baryon spectroscopy, investigating the spectrum and the properties of baryon…
Characteristics of the hadronic final state of diffractive deep inelastic scattering events, ep -> eXp, were studied in the kinematic range 4 < M_X < 35 GeV, 4 < Q^2 < 150 GeV^2, 70 < W < 250 GeV and 0.0003 < x_pom < 0.03 with the ZEUS…
Hadron spectroscopy is an important tool towards the study of internal quark dynamics in a composite system. The present article focuses on the study of resonance spectra of strange baryons with S=-2, -3. The non-relativistic approach…
In semi-inclusive deep inelastic scattering of polarized leptons on a transversely polarized target eight target transverse spin-dependent azimuthal modulations are allowed. In the QCD parton model half of these asymmetries can be…
The electric alpha and magnetic beta pion Compton polarizabilities characterize the pion's deformation in the electromagnetic field of the gamma during gamma-pi Compton scattering. The pion polarizabilities are key observables, and provide…
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…
The COMPASS collaboration has collected the currently largest data set on diffractively produced $\pi^-\pi^-\pi^+$ final states using a negative pion beam of 190 GeV/c momentum impinging on a stationary proton target. This data set allows…
The HERMES experiment is collecting data on inclusive and semi-inclusive deep inelastic scattering of polarised positrons from polarised targets of H, D, and He. These data give information on the spin structure of the nucleon. This paper…