Related papers: Freed-Isobar Analysis of Light Mesons at COMPASS
A phase shift and sum (PSAS) algorithm to image objects in dispersive media is presented. The algorithm compensates the phase shift of the scattered field from the receiver to the source for each frequency component in an ultrawideband…
In quantum technologies, it is essential to understand and exploit the interplay of light and matter. We introduce an approach, creating and maintaining the coherence of four oscillators: a global microwave reference field, a…
The COMPASS experiment has obtained first physics results in the field of polarized distribution functions for quarks and gluons using muon scattering off polarized deuterons. The analysis using open charm production and pairs of high $p_T$…
A unitary coupled-channels model is presented for investigating the decays of heavy mesons and excited meson states into three light pseudoscalar mesons. The model accounts for the three-mesons final state interactions in the decay…
Magnonics is seen nowadays as a candidate technology for energy-efficient data processing in classical and quantum systems. Pronounced nonlinearity, anisotropy of dispersion relations and phase degree of freedom of spin waves require…
This dissertation treats the problem of complete experiments for pseudoscalar meson photoproduction, in the context of a truncated partial-wave analysis (TPWA). The work contains algebraic and numerical considerations. The influence of…
Partial wave amplitudes for production and decay of baryon resonances are constructed in the framework of the operator expansion method. The approach is fully relativistically invariant and allow us to perform combined analyses of different…
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…
Pulsar Timing Array (PTA) searches for nHz gravitational-wave backgrounds (GWBs) typically model time-correlated noise by assuming a diagonal covariance in Fourier space, neglecting inter-frequency correlations introduced by the finite…
Properties of scalar-isoscalar mesons are analysed using separable interactions in three decay channels: pion-pion, kaon-antikaon and an effective 2pion-2pion. We obtain different solutions by fitting various data on the pion-pion and…
Noise subtraction is a crucial process in gravitational wave (GW) data analysis to improve the sensitivity of interferometric detectors. While linear noise coupling has been extensively studied and successfully mitigated using methods such…
A search for exotic mesons in the $\pi^{+}\pi^{+}\pi^{-}$ system photoproduced by the charge exchange reaction $\gamma p\to \pi^{+}\pi^{+}\pi^{-}(n)$ was carried out by the CLAS collaboration at Jefferson Lab. A tagged-photon beam with…
Meson spectroscopy is going through a revival with the advent of high statistics experiments and new advances in the theoretical predictions. The Constituent Quark Model (CQM) is finally being expanded considering more basic principles of…
A generalized plasma model having warm ions, iso-thermal electrons, super-thermal electrons and positrons is considered to theoretically investigate the modulational instability (MI) of ion-acoustic waves (IAWs). A standard nonlinear…
One of the important goals of the COMPASS experiment is the determination of the gluonic contribution to the spin of the nucleon. By using the photon gluon fusion (PGF) process in polarised deep inelastic scattering direct access to the…
Structures in the invariant mass distribution are often linked to unstable intermediate states or resonances. In experiments, many signals are detected which have broad, overlapping or intricate profiles, which makes their characterization…
Matter-wave interferometry is a highly sensitive tool to measure small perturbations in a quantum system. This property allows the creation of precision sensors for dephasing mechanisms such as mechanical vibrations. They are a challenge…
Pulsar timing arrays aim to detect nanohertz-frequency gravitational waves (GWs). A background of GWs modulates pulsar arrival times and manifests as a stochastic process, common to all pulsars, with a signature spatial correlation. Here we…
Experiments that study the photoproduction of pseudoscalar mesons; pions, etas and kaons, have the potential to increase our knowledge of baryon and hyperon resonance properties. Recent experiments at JLab, Mainz, GRAAL, and Bonn are…
While the spectrum of non-strange light mesons is well known, many predicted strange mesons have not yet been observed, and many potentially observed states require further confirmation. Using the $K^-$ component of the hadron beam at the…