scholarly journals Strong CP violation in spin-1/2 singly charmed baryons

2021 ◽  
Vol 2021 (1) ◽  
Author(s):  
Y. Ünal ◽  
Ulf-G. Meißner
Keyword(s):  
Perturbation Theory ◽  
Dipole Moment ◽  
Form Factor ◽  
Cp Violation ◽  
Mass Shell ◽  
Chiral Expansion ◽  
Renormalization Scheme ◽  
Leading Order ◽  
Chiral Perturbation ◽  
Charmed Baryons

Abstract We report on the calculation of the CP-violating form factor F3 and the corresponding electric dipole moment for charmed baryons in the spin-1/2 sector generated by the QCD θ-term. We work in the framework of covariant baryon chiral perturbation theory within the extended-on-mass-shell renormalization scheme up to next-to-leading order in the chiral expansion.

scholarly journals LOWEST-LYING OCTET BARYON MASSES IN COVARIANT BARYON CHIRAL PERTURBATION THEORY

2014 ◽  
Vol 26 ◽  
pp. 1460068
Author(s):  
XIU-LEI REN ◽  
LISHENG GENG ◽  
JIE MENG ◽  
HIROSHI TOKI
Keyword(s):  
Perturbation Theory ◽  
Chiral Perturbation Theory ◽  
Mass Shell ◽  
Renormalization Scheme ◽  
Leading Order ◽  
Chiral Perturbation ◽  
Octet Baryon ◽  
Self Consistent ◽  
Reasonable Description ◽  
Consistent Treatment

We report on a systematic study of the ground-state octet baryon masses in the covariant baryon chiral perturbation theory with the extended-on-mass-shell renormalization scheme up to next-to-next-to-next-to-leading order, taking into account the contributions of the virtual decuplet baryons. A reasonable description of the lattice results is achieved by fitting simultaneously all the publicly availablenf = 2 + 1lattice QCD data. It confirms that the various lattice simulations are consistent with each other. We stress that a self-consistent treatment of finite-volume corrections is important to obtain a χ2/d.o.f. about 1.

Lowest-lying octet baryon masses up to $\mathcal{O}(p^4)$ in covariant baryon chiral perturbation theory

2014 ◽  
Vol 29 ◽  
pp. 1460215
Author(s):  
Xiu-Lei Ren ◽  
Lisheng Geng ◽  
Jie Meng ◽  
Hiroshi Toki
Keyword(s):  
Perturbation Theory ◽  
Chiral Perturbation Theory ◽  
Mass Shell ◽  
Renormalization Scheme ◽  
Low Energy ◽  
Tree Level ◽  
Chiral Perturbation ◽  
Octet Baryon ◽  
Reasonable Description ◽  
Energy Constants

In this talk, we report on a systematic study of the lowest-lying octet baryon masses in covariant baryon chiral perturbation theory with the extended-on-mass-shell renormalization scheme up to [Formula: see text]. By adjusting the low-energy constants, a reasonable description of the nf = 2 + 1 lattice results is achieved with χ2/d.o.f. about 1. It confirms that the various lattice simulations are consistent with each other. We also find that the virtual decuplet effects on the baryon masses cannot be disentangled from those of the virtual octet baryons and the tree level diagrams.

scholarly journals The electric dipole form factor of the nucleon in chiral perturbation theory to sub-leading order

2011 ◽  
Vol 696 (1-2) ◽  
pp. 97-102 ◽  
Author(s):  
E. Mereghetti ◽  
J. de Vries ◽  
W.H. Hockings ◽  
C.M. Maekawa ◽  
U. van Kolck
Keyword(s):  
Perturbation Theory ◽  
Form Factor ◽  
Chiral Perturbation Theory ◽  
Electric Dipole ◽  
Leading Order ◽  
Chiral Perturbation ◽  
Dipole Form Factor ◽  
Dipole Form

scholarly journals Chiral perturbation theory and nucleon–pion-state contaminations in lattice QCD

2017 ◽  
Vol 32 (15) ◽  
pp. 1730011 ◽  
Author(s):  
Oliver Bär
Keyword(s):  
Perturbation Theory ◽  
Chiral Perturbation Theory ◽  
Distribution Functions ◽  
Leading Order ◽  
Chiral Perturbation ◽  
Parton Distribution Functions ◽  
Physical Point ◽  
Source Sink ◽  
The Impact ◽  
Quark Momentum

Multiparticle states with additional pions are expected to be a non-negligible source of excited-state contamination in lattice simulations at the physical point. It is shown that baryon chiral perturbation theory can be employed to calculate the contamination due to two-particle nucleon–pion-states in various nucleon observables. Leading order results are presented for the nucleon axial, tensor and scalar charge and three Mellin moments of parton distribution functions (quark momentum fraction, helicity and transversity moment). Taking into account phenomenological results for the charges and moments the impact of the nucleon–pion-states on lattice estimates for these observables can be estimated. The nucleon–pion-state contribution results in an overestimation of all charges and moments obtained with the plateau method. The overestimation is at the 5–10% level for source-sink separations of about 2 fm. The source-sink separations accessible in contemporary lattice simulations are found to be too small for chiral perturbation theory to be directly applicable.

scholarly journals Two-flavor chiral perturbation theory at nonzero isospin: pion condensation at zero temperature

2019 ◽  
Vol 79 (10) ◽  
Author(s):  
Prabal Adhikari ◽  
Jens O. Andersen ◽  
Patrick Kneschke
Keyword(s):  
Perturbation Theory ◽  
Equation Of State ◽  
Condensed Phase ◽  
Chiral Perturbation Theory ◽  
Chemical Potential ◽  
Tree Level ◽  
Zero Temperature ◽  
Leading Order ◽  
Chiral Perturbation ◽  
Pion Condensation

Abstract In this paper, we calculate the equation of state of two-flavor finite isospin chiral perturbation theory at next-to-leading order in the pion-condensed phase at zero temperature. We show that the transition from the vacuum phase to a Bose-condensed phase is of second order. While the tree-level result has been known for some time, surprisingly quantum effects have not yet been incorporated into the equation of state.  We find that the corrections to the quantities we compute, namely the isospin density, pressure, and equation of state, increase with increasing isospin chemical potential. We compare our results to recent lattice simulations of 2 + 1 flavor QCD with physical quark masses. The agreement with the lattice results is generally good and improves somewhat as we go from leading order to next-to-leading order in $$\chi $$χPT.

scholarly journals Quark and pion condensates at finite isospin density in chiral perturbation theory

2020 ◽  
Vol 80 (11) ◽  
Author(s):  
Prabal Adhikari ◽  
Jens O. Andersen
Keyword(s):  
Perturbation Theory ◽  
Chiral Perturbation Theory ◽  
Chemical Potential ◽  
Chiral Condensate ◽  
Zero Temperature ◽  
Leading Order ◽  
Chiral Perturbation ◽  
Pion Condensate ◽  
Independent Analysis ◽  
Model Independent

AbstractIn this paper, we consider two-flavor QCD at zero temperature and finite isospin chemical potential $$\mu _I$$ μ I using a model-independent analysis within chiral perturbation theory at next-to-leading order. We calculate the effective potential, the chiral condensate and the pion condensate in the pion-condensed phase at both zero and nonzero pionic source. We compare our finite pionic source results for the chiral condensate and the pion condensate with recent (2+1)-flavor lattice QCD results. Agreement with lattice results generally improves as one goes from leading order to next-to-leading order.

Sign in / Sign up

Export Citation Format

Share Document