Related papers: Nucleon Strangeness: Theory
The HERMES collaboration in Phys. Rev. D89 (2014) 097101 extracted information about the strange quark density in the nucleon. One of the main results is an observation that the shape of the extracted density is very different from the…
Does deconfined cold quark matter occur in nature? This is currently one of the fundamental open questions in nuclear astrophysics. In these proceedings, I review the current state-of-the-art techniques to address this question in a…
Precise proton and neutron form factor measurements at Jefferson Lab, using spin observables, have recently made a significant contribution to the unraveling of the internal structure of the nucleon. Accurate experimental measurements of…
We present results for the strange contribution to the electromagnetic form factors of the nucleon computed on the CLS ensembles with $N_f=2+1$ flavors of $\mathcal{O}(a)$-improved Wilson fermions and an $\mathcal{O}(a)$-improved vector…
Calculations of form factors in different forms of relativistic kinematics are presented. They involve the instant, front and point forms. In the two first cases, different kinematical conditions are considered while in the latter case,…
We investigate the role of correlated $\pi\rho$ exchange in the extraction of matrix elements of the strange vector current in the proton. We show that a realistic isoscalar spectral function including this effect leads to sizeably reduced…
Baryon form factors can be analyzed in a largely model-independent fashion in terms of two complementary approaches. These are chiral perturbation theory and dispersion relations. I review the status of dispersive calculations of the…
We discuss the latest CCFR determination of the strange sea density of the proton. We comment on the differences with a previous, leading--order, result and point out the relevance of quark mass effects and current non--conservation…
We investigate the imaginary parts of the nucleon electromagnetic and axial form factors close to threshold in the framework of heavy baryon chiral perturbation theory. For the isovector electromagnetic form factors, we recover the well…
A synopsis exemplifying the employment of Dyson-Schwinger equations in the calculation and explanation of hadron electromagnetic form factors and related phenomena. In particular the contribution: presents the pion form factor computed…
In this talk we discuss possible signatures for the existence of strange quark matter stars (strange stars).
We have revisited the calculation of the neutron electric dipole moment in the presence of the CP-violating operators up to dimension five based on the chiral perturbation theory. Especially, we focus on the contribution of strangeness…
The sea quark contributions to the nucleon electromagnetic form factors from up, down and strange quarks are studied with the nonlocal chiral effective Lagrangian. Both octet and decuplet intermediate states are included in the one loop…
We perform a calculation of the relativistic corrections to the electromagnetic elastic form factors of the nucleon obtained with various Constituent Quark Models. With respect to the non relativistic calculations a substantial improvement…
Some recent discoveries in the spectroscopy of hadrons containing heavy quarks, and some of their theoretical interpretations, are reviewed.
The present status of the nucleon's spin structure is reviewed with emphasis on new experimental results.
We present the nucleon strange electromagnetic form factors using four lattice QCD ensembles with $N_f=2+1+1$ twisted mass clover-improved fermions and quark masses tuned to approximately their physical values. The four ensembles have…
Scalar matrix elements involving strange quarks are studied in several models. Apart from a critical reexamination of results obtained in the Nambu and Jona-Lasinio model we study a scenario, motivated by instanton physics, where…
The treatment of nuclear effects in neutrino-nucleus interactions is one of the main sources of systematic uncertainty for the analysis and interpretation of data of neutrino oscillation experiments. Neutrinos interact with nuclei via…
We compute the nucleon axial and induced pseudoscalar form factors using three ensembles of gauge configurations, generated with dynamical light quarks with mass tuned to approximately their physical value. One of the ensembles also…