Searcharxiv⌕ Search

arXiv subjects

N. I. Troitskaya

Publications and source records attributed to N. I. Troitskaya.

81 records · Page 5Linked to original sources
arXiv1997

On the $D^+_s \to π^+ π^+ π^-$ - nonresonant decay in the effective quark model with chiral symmetry

The partial widths of the decays $D^+_s \to ϕπ^+$ and $D^+_s \to π^+ π^+ π^-$ - nonresonant are computed within the effective quark model with chiral symmetry involving Heavy quark effective theory (HQET) and Chiral perturbation theory at the quark level (CHPT)$_q$ with linear realization of chiral U(3) x U(3) symmetry. It is shown that for the explanation of the experimental probability of the $D^+_s \to π^+ π^+ π^-$ - nonresonant decay one does not need to use unnaturally heavy light current quarks as has been suggested in Ref.[1]. The life time of the $D^+_s$ - meson $τ_{D^+_s} = (0.59\pm 0.19) x 10^(-12) s$ is computed in good agreement with the experimental one.

hep-ph↗
arXiv1997

On the D*D$π$ and B*B$π$ coupling constants in the effective quark model with chiral symmetry

The coupling constants of D*D$π$ and B*B$π$ strong interactions are computed in the effective quark model with chiral symmetry incorporating Heavy quark effective theory (HQET) and Chiral perturbation theory at the quark level with linear realization of chiral U(3)XU(3) symmetry. We predict g(D*D$π$) = 5.2 and g(B*B$π$) = 14.3. The corrections of large heavy quark mass expansion to the constants g(D*D$π$) and g(B*B$π$) are calculated and make up less than 1 per cent.

hep-ph↗
arXiv1997

On the relativistic field theory model of the deuteron II

The relativistic field theory model of the deuteron is applied to the calculation of the cross sections of the low-energy radiative neutron-proton capture n + p -> D + gamma and the low-energy two-proton fusion p + p -> D + e^+ + nu_e. For the low-energy radiative neutron-proton capture n + p -> D + gamma our result agrees well with both the experimental data and the potential model prediction. In the case of the two-proton fusion the cross section obtained is 2.9 times as much as that given by the potential approach. The obtained result is discussed in connection with the solar neutrino problem. ERRATUM: We correct the value of the cross section for pp-fusion p + p -> D + e^+ + nu_e. We find a contribution to the astrophysical factor δS_pp(0) = 2.01 x 10^{-25} (1 +/- 0.30) MeV b which is obtained only due to weak and strong low-energy interactions of the protons and the deuteron when neglecting the Coulomb repulsion between protons in the intermediate state. Minor misprints are corrected.

nucl-th↗
arXiv1997

Nuclear aspects of the solar neutrino problem

The present status of the nuclear reaction rates determining the solar neutrino flux is discussed. This includes the reaction rates for the two branching ratios of the three pp-chains involving the reactions 3He(3He,2p)4He and 3He(4He,gamma)7Be for the first branching, and 7Be(e-,nu_e)7Li and 7Be(p,gamma)7B for the second branching. Mainly we will concentrate on the basic nuclear reaction p + p -> D + e+ + nu_e of the pp-chains. We use a relativistic field theory model of the deuteron to calculate the low-energy cross section for this reaction. The theoretical prediction of the cross section obtained is about 2.9 times largerthan given in the conventional potential approach. The consequences of this new reaction rate for the solar neutrino problem will be presented and discussed.

nucl-th↗
arXiv1997

On the solar neutrino problem in the relativistic field theory model of the deuteron

The relativistic field theory model of the deuteron suggested by us previously is applied to the calculation of the reaction rate of the low-energy two-proton fusion p + p -> D + e+ + nu. The theoretical prediction of the reaction rate obtained is 2.9 times larger than given by the potential approach. This leads to a strong suppression of the high energy solar neutrino fluxes.

astro-ph↗
arXiv1995

On the Form Factors of the $D_{s}^{+}\to ϕμ^{+}ν_μ decay

We apply the infinite mass effective theory, when a heavy quark mass tends to infinity, and Chiral perturbation theory at the quark level, based on the extended Nambu -- Jona -- Lasinio model with linear realization of chiral $U(3)\times U(3)$ symmetry, to calculate the form factors of the $D^{\,+}_{\,s}\toϕ~μ^+~ν_{\,μ}$ decay up to the first order in current $s$ -- quark mass. The theoretical results are compared with experimental data and found to be in good agreement.

hep-ph↗
arXiv1995

Current s-Quark Mass Corrections to the Form Factors of D-Meson Semileptonic Decays

The infinite mass effective theory, when a heavy quark mass tends to infinity, and Chiral perturbation theory at the quark level, based on the extended Nambu -- Jona -- Lasinio model with linear realization of chiral $U(3)\times U(3)$ symmetry, are applied to the calculation of current $s$ -- quark mass corrections to the form factors of the $D\to\bar K~e^+~ν_e$ and $D\to\bar K^{\ast}~e^+~ν_e$ decays. These corrections turn out to be quite significant, of the order of $7-20\%$. The theoretical results are compared with experimental data.

hep-ph↗
arXiv1993

Spontaneous Breaking of Chiral Symmetry as a Consequence of Confinement

We show that at the leading order in the large-$N$ expansion a lattice QCD motivated linear rising confinement potential at large distances leads to a non-local four-quark interaction that realizes spontaneous breaking of chiral symmetry (SBCS) in the same way the Nambu-Jona-Lasinio model does. The dynamical quark mass $m$, which represents the solution of the gap-equation, is proportional to the square root of the string tension $σ$ and takes the form at the leading order in the large-$N$ expansion $m=2 \sqrtσ/π$ with $σ=0.27$ GeV$^2$. The Nambu-Jona-Lasinio phenomenological constant $G_1$, which is responsible for SBCS, is expressed in terms of the string tension and the confinement radius.

hep-ph↗