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Exotic hadrons with heavy quarks in EFT approach
Get PDFThe approach to exotic hadrons with heavy quarks based on the
Effective Field Theory is reviewed and its application to particular near-threshold exotic states in the spectrum of charmonium and bottomonium is discussed
Exotic spectroscopy in a diquark model with a little help from AdS/QCD
Get PDFMasses of heavy mesons, tetraquarks and pentaquarks computed
in a potential model are shown. Tetraquarks are studied as bound states of a diquark and an antidiquark. Pentaquarks are constructed from a series of two-body interactions between the four quarks and the antiquark. New results on QsQ¯q¯ and
QQQ¯Q¯ tetraquarks are also obtained
A study of K−d and K+d interactions via femtoscopy technique
Get PDFScattering cross-section measurements have been used to study the strong interaction between charged kaons and (anti-)deuterons. However, these studies have not been successful in determining the scattering lengths of the strong interaction between K+d and K−d. Moreover, the currently available theoretical predictions for the K−d scattering parameter are largely based on input from kaonic
hydrogen measurements, while no theoretical predictions have yet been published for K+d. In this work, the first measurements of the scattering lengths of K+d and K−d particle pairs are presented. The results were obtained using the femtoscopy technique which is very accurate for studying interactions between two particles with low relative momenta
Dispersive calculation for N∗(1520) transition form factors at low energies
Get PDFThe transition form factors of N∗(1520) have been formulated
and computed at low energies (|q2| < 1 GeV2) using dispersion theory for the first time. Utilizing hadronic data from N∗(1520) → Nπ, N∗(1520) → Δπ, and N∗(1520) → N ρ processes, we have calculated both space-like and time-like transition form factors. Our results demonstrate agreement with the existing space-like form factor data. The predicted time-like form factors can be experimentally tested by the HADES experiment
Near-threshold J/ψ photoproduction off the proton and neutron with CLAS12
Get PDFNear-threshold J/ψ photoproduction plays a key role in the physics program at the Thomas Jefferson National Accelerator Facility (JLab) 12 GeV upgrade due to the wealth of information it has to offer. J/ψ photoproduction proceeds through the exchange of gluons in the t-channel and is expected to provide unique insight about the nucleon gluonic form factors and the nucleon mass radius. The JLab-based CLAS Collaboration, which uses the CEBAF Large Acceptance
Spectrometer (CLAS12), aims to measure the near-threshold J/ψ photoproduction cross-section using both a proton and a deuteron target. The latter further offers the possibility of comparing the proton and neutron gluonic form factors and mass radii in a first measurement of the cross-sections off a proton or neutron within the deuteron target. These proceedings will describe the aims and experimental
design for the measurement of near-threshold J/ψ photoproduction off the proton and neutron with the CLAS12 detector along with the current stage of the data analysis
Studying gluon GPDs at the EIC via DVMP
Get PDFThe Electron Ion Collider (EIC) is a next-generation hadron physics facility, planned to be built in the coming decade at Brookhaven National Laboratory (BNL), with the intention of further exploring the quark and gluon substructure of hadrons and nuclei. The EIC will address fundamental questions in QCD, probing the interplay of quarks and gluons to learn how they contribute to overall nucleon properties, and how they are affected by the nuclear environment. With heavy ion beams to enable in-depth studies of nuclear matter, alongside the precision of the electromagnetic interaction and the determinative properties of polarised nucleon beams, the EIC is expected to provide scientific opportunities for decades to come. Hard exclusive meson electroproduction processes, also known as deeply virtual meson production (DVMP), are complimentary to the deeply virtual Compton scattering (DVCS) reaction. In DVMP, the scattering reaction produces a meson instead of a photon, and through the study of heavy vector meson reactions, such
as J/Ψ, it is possible to probe gluon GPDs and ultimately provide information about saturation when studying the evolution of gluon spatial distribution. The work presented focuses on studies of J/Ψ → e+e− events from ep collisions, and the evaluation of projected detector performance for DVMP measurements in an EIC detector concept. Prospects for extending these studies to other vector meson channels, from φ to Υ, are also discussed
Testing predictions of the chiral anomaly in Primakoff reactions at COMPASS
Get PDFThe chiral anomaly is a fundamental property of quantum chromodynamics (QCD). It governs the transition amplitudes for processes involving an odd number of Goldstone bosons of chiral symmetry breaking. In case of the coupling of three pions to a photon, the magnitude of the resulting coupling is F3π and the value is predicted by chiral perturbation theory with small uncertainty. It can experimentally be measured in π−γ → π−π0 scattering. Here, we report on a precision experiment on F3π using the COMPASS experiment at CERN where pion-photon scattering is mediated via the Primakoff effect using heavy nuclei as target. We exploit the interference of the production of the π−π0 final state via the chiral anomaly with the photo-production of the ρ(770) resonance over a wide mass range Mπ−π0 < 1 GeV/c2. This is in contrast to previous measurements restricting
themselves only to the threshold region Mπ−π0 < 370 MeV. Our analysis allows to simultaneously extract the radiative width of the ρ(770) resonance and gives a stronger handle on F3π in a unified approach thereby minimizing systematic effects rarely addressed previously
Dialogo sul suicidio medicalmente assistito
Get PDFIl nuovo volume “Dialogo sul suicidio medicalmente assistito” realizzato dal Centro Interdipartimentale per l’Etica e l’Integrità nella Ricerca del CNR in collaborazione con la Consulta Scientifica del Cortile dei Gentile analizza diverse tematiche che nell'introduzione di Giuliano Amato sono ben evidenziate:
“Il suicidio assistito è un tema su cui esistono, e sono fortemente radicate, opinioni diverse. Hanno spesso fonte religiosa, ma non solo. Nota il documento qui pubblicato, e proprio al suo esordio, che la differenza fra lasciar morire e aiutare a morire ha fonti epistemologiche e non c’è volontarismo, di nessun genere, che possa cancellarle. Di ciò, noi del Cortile, siamo abituati a prendere atto, si tratta anzi, quasi sempre, del nostro punto di partenza; partenza verso la ricerca di un punto di incontro, che non sacrifichi l’opinione di alcuno, ma consenta di convergere verso soluzioni, che comunque tengono conto di tutti. È quello che, sia pure con difficoltà e con dubbi che rimangono aperti a ulteriori riflessioni, è accaduto anche questa volta. Certo, ci ha unito il rispetto degli uni per i principi degli altri […]. Ma ciò che ci ha consentito di procedere in una ricerca comune […] è stata la comune volontà di non metterli esplicitamente in campo davanti a circostanze nelle quali dominante era ed è per tutti noi un fortissimo e fortemente condiviso fattore comune: la pietà umana, che è insieme sentimento di solidarietà e fonte di azione solidale.
The LHCspin project: A polarized target experiment at LHC
Get PDFA polarized target, operated in combination with the high-energy, high-intensity LHC beams and a highly performing LHC particle detector, has the potential to open new physics frontiers and to deepen our understanding of the intricacies of the strong interaction in the non-perturbative regime of QCD. Specifically, the LHCspin project aims to perform spin physics studies in high-energy polarized fixed-target collisions using the LHCb detector. Being designed and optimized for the detection of heavy hadrons, the LHCb spectrometer, in combination with the LHCspin setup, will provide a complementary access to the nucleon structure, e.g., by studying inclusive production of c- and b-hadrons, which represent an ideal tool to access the essentially unexplored spin-dependent gluon TMDs. Furthermore, fixedtarget collisions with 7 TeV proton beams, corresponding to center-of-mass energies ranging from 115 GeV in pp interactions to 72 GeV per nucleon in collisions with ion beams, will allow to cover a wide backward rapidity region, corresponding to the poorly explored high x-Bjorken and high x-Feynman regimes. The status of the LHCspin project is presented along with a selection of physics opportunities
Lepton flavour universality tests using semileptonic b-hadron decays at LHCb
Get PDFThe standard model assumes that the three charged leptons, namely electrons e, muons μ, and taus τ , have an identical electroweak coupling, and the distinction arises from their different masses. Several independent experiments,
including BaBar, Belle, and LHCb, have found deviations from SM predictions. Some of these anomalies arises in the b → cν transition, referred to as charged anomalies. Recent measurements have been reported with the purpose of addressing these anomalies, a brief overview of these results is provided. It is worth noting that the overall tension between theoretical predictions based on the Standard Model and the world average including these new measurements remains at the 3σ level