scholarly journals Study on branching ratios and direct CP asymmetries of D → PV decays

2014 ◽  
Vol 29 ◽  
pp. 1460209 ◽  
Author(s):  
Qin Qin ◽  
Hsiang-Nan Li ◽  
Cai-Dian Lü ◽  
Fu-Sheng Yu
Keyword(s):  
Experimental Data ◽  
Pseudoscalar Meson ◽  
Short Distance ◽  
D Mesons ◽  
Branching Ratios ◽  
Matrix Elements ◽  
Long Distance ◽  
Global Fit ◽  
Belle Ii ◽  
Cp Asymmetries

We study the non-leptonic two-body decays of D mesons decaying into one pseudoscalar meson (P) and one vector meson (V) in the factorization-asisted topological-amplitude approach. In this approach, the decay amplitudes are factorized into two parts, the short-distance contribution (Wilson coefficients) and the long-distance contribution (hadronic matrix elements). We predict the branching ratios of D → PV decays using a global fit with the non-perturbative parameters. Our results agree well with the experimental data. We also predict the direct CP asymmetries by combining short-distance dynamics associated with penguin operators and long-distance hadronic matrix elements determined by branching ratios. The large asymmetries in D+ → π+ρ0 and [Formula: see text] may be measurable in the LHCb and future Belle II experiments.

NEW RESULT OF DIRECT CP VIOLATION IN B → π+π-π+π-

2011 ◽  
Vol 26 (17) ◽  
pp. 2899-2912 ◽  
Author(s):  
GANG LÜ ◽  
ZHEN-HUA ZHANG ◽  
XIU-YING LIU ◽  
LI-YING ZHANG
Keyword(s):  
Experimental Data ◽  
Cp Violation ◽  
Invariant Mass ◽  
Branching Ratios ◽  
Effective Parameter ◽  
Matrix Elements ◽  
Strong Constraint ◽  
Ckm Matrix ◽  
First Order ◽  
Isospin Violation

In the framework of factorization, based on the first-order of isospin violation, we study direct CP violation in the decay of [Formula: see text] including the effect of ρ–ω mixing. The CP violation depends strongly on Cabibbo–Kobayashi–Maskawa (CKM) matrix elements and the effective parameter, Nc. Recently, the experimental data for the branching ratios of [Formula: see text] are accurate and we can give the strong constraint on the range of Nc. We find that the CP violating asymmetry is large and ranges from -82% to -98% via ρ–ω mixing mechanism when the invariant mass of the π+π- pair is in the vicinity of the ω resonance. We also discuss the possibility to observe the predicted CP violating asymmetries at the LHC.

scholarly journals Gluon fragmentation into 3$$ {P}_J^{\left[1,8\right]} $$ quark pair and test of NRQCD factorization at two-loop level

2021 ◽  
Vol 2021 (8) ◽  
Author(s):  
Peng Zhang ◽  
Ce Meng ◽  
Yan-Qing Ma ◽  
Kuang-Ta Chao
Keyword(s):  
Short Distance ◽  
Distance Matrix ◽  
Matrix Elements ◽  
Leading Order ◽  
Long Distance ◽  
Loop Level ◽  
Matching Procedure ◽  
Fragmentation Functions ◽  
Infrared Divergences ◽  
Gluon Fragmentation

Abstract The next-to-leading order (NLO) ($$ \mathcal{O} $$ O ($$ {\alpha}_s^3 $$ α s 3 )) corrections for gluon fragmentation functions to a heavy quark-antiquark pair in 3$$ {P}_J^{\left[1,8\right]} $$ P J 1 8 states are calculated within the NRQCD factorization. We use the integration-by-parts reduction and differential equations to semi-analytically calculate the fragmentation functions in full-QCD, and find that infrared divergences can be absorbed by the NRQCD long distance matrix elements. Thus, the NRQCD factorization conjecture is verified at two-loop level via a physical process, which is free of artificial ultraviolet divergences. Through the matching procedure, infrared-safe short distance coefficients and $$ \mathcal{O} $$ O ($$ {\alpha}_s^2 $$ α s 2 ) perturbative NRQCD matrix elements ⟨$$ {\mathcal{O}}^3{P}_J^{\left[1,8\right]} $$ O 3 P J 1 8 (3$$ {S}_1^{\left[8\right]} $$ S 1 8 )⟩ are obtained simultaneously. The NLO short distance coefficients are found to have significant corrections comparing with the LO ones.

scholarly journals Parton distributions in the LHC era

2018 ◽  
Vol 175 ◽  
pp. 01006 ◽  
Author(s):  
Luigi Del Debbio
Keyword(s):  
Experimental Data ◽  
First Principles ◽  
Short Distance ◽  
Distribution Functions ◽  
Parton Distribution Functions ◽  
Long Distance ◽  
Standard Description ◽  
Parton Distributions ◽  
Distance Properties ◽  
The Impact

Analyses of LHC (and other!) experiments require robust and statistically accurate determinations of the structure of the proton, encoded in the parton distribution functions (PDFs). The standard description of hadronic processes relies on factorization theorems, which allow a separation of process-dependent short-distance physics from the universal long-distance structure of the proton. Traditionally the PDFs are obtained from fits to experimental data. However, understanding the long-distance properties of hadrons is a nonperturbative problem, and lattice QCD can play a role in providing useful results from first principles. In this talk we compare the different approaches used to determine PDFs, and try to assess the impact of existing, and future, lattice calculations.

scholarly journals RADIATIVE LEPTONIC DECAYS OF THE CHARGED B AND D MESONS INCLUDING LONG-DISTANCE CONTRIBUTION

2012 ◽  
Vol 27 (22) ◽  
pp. 1250120 ◽  
Author(s):  
JI-CHONG YANG ◽  
MAO-ZHI YANG
Keyword(s):  
Short Distance ◽  
D Mesons ◽  
Bound State ◽  
Vector Meson Dominance ◽  
Dominance Model ◽  
Long Distance ◽  
Leptonic Decays ◽  
Bound State Wave Function ◽  
Vector Meson Dominance Model ◽  
Relativistic Potential

In this work, we study the radiative leptonic decays of B-, D-and [Formula: see text], including both the short-distance and long-distance contributions. The short-distance contribution is calculated by using the relativistic quark model, where the bound state wave function we used is that obtained in the relativistic potential model. The long-distance contribution is estimated by using vector meson dominance model.

scholarly journals NONFACTORIZABLE LONG DISTANCE CONTRIBUTIONS IN COLOR SUPPRESSED DECAYS OF B MESONS

1998 ◽  
Vol 13 (25) ◽  
pp. 4325-4338 ◽  
Author(s):  
K. TERASAKI
Keyword(s):  
Experimental Data ◽  
B Mesons ◽  
Branching Ratios ◽  
Unknown Parameters ◽  
Long Distance

[Formula: see text], D*π, [Formula: see text] and J/ψπ decays are studied. Their amplitude is given by a sum of factorized and nonfactorizable ones. The latter which is estimated by using a hard pion approximation is rather small in color favored [Formula: see text] and D*π decays but still can efficiently interfere with the main amplitude given by the factorization. In the color suppressed [Formula: see text] and J/ψπ decays, the nonfactorizable contribution is very important. The sum of the factorized and nonfactorizable amplitudes can reproduce well the existing experimental data on the branching ratios for the color favored [Formula: see text] and D*π and the color suppressed [Formula: see text] and J/ψπ decays by taking reasonable values of unknown parameters involved.

WEAK DECAYS OF B−, $\bar{B}^0$ MESONS TO A PSEUDOSCALAR AND A SCALAR MESON IN THE FINAL STATE

1996 ◽  
Vol 11 (01) ◽  
pp. 129-139 ◽  
Author(s):  
A.C. KATOCH ◽  
R.C. VERMA
Keyword(s):  
Quark Model ◽  
Pseudoscalar Meson ◽  
Scalar Meson ◽  
Form Factors ◽  
Branching Ratios ◽  
Matrix Elements ◽  
Final State ◽  
Factorization Scheme ◽  
Weak Decays

Using the factorization scheme, we study two-body exclusive weak decays of B– and [Formula: see text] mesons to a pseudoscalar meson and a scalar meson in the final state. Employing the Isgur-Scora-Grinstein-Wise quark model to obtain the form factors involved in the decay matrix elements, we calculate the branching ratios for the decays involving b→c transition.

scholarly journals Branching ratios and CP asymmetries of B decays to a vector and a pseudoscalar meson

2000 ◽  
Vol 473 (1-2) ◽  
pp. 141-147 ◽  
Author(s):  
N.G. Deshpande ◽  
B. Dutta ◽  
Sechul Oh
Keyword(s):  
Pseudoscalar Meson ◽  
Branching Ratios ◽  
B Decays ◽  
Cp Asymmetries

scholarly journals LARGE SU(3) BREAKING EFFECTS AND CP VIOLATION IN B+ DECAYS INTO THREE CHARGED OCTET PSEUDOSCALAR MESONS

2014 ◽  
Vol 29 (03n04) ◽  
pp. 1450011 ◽  
Author(s):  
DONG XU ◽  
GUAN-NAN LI ◽  
XIAO-GANG HE
Keyword(s):  
Experimental Data ◽  
Cp Violation ◽  
Branching Ratios ◽  
Lhcb Collaboration ◽  
The Other ◽  
Order Derivative ◽  
B Decays ◽  
Pseudoscalar Mesons ◽  
Cp Asymmetries

The LHCb collaboration has recently reported evidence for nonzero CP asymmetries in B+ decays into π+K+K-, π+π+π-, K+K+K- and K+π+π-. The branching ratios for these decays have also been measured with different values ranging from 5×10-6 to 51×10-6. If flavor SU(3) symmetry is a good symmetry for B decays, in the case that the dominant amplitude is momentum independent it is expected that branching ratios Br and CP violating rate differences [Formula: see text] satisfy, Br (π+π+π-) = 2 Br (π+K+K-), Br (K+K+K-) = 2 Br (K+π+π-) and Δ CP (π+π+π-) = 2Δ CP (π+K+K-) = -Δ CP (K+K+K-) = -2Δ CP (K+π+π-). The experimental data do not exhibit the expected pattern for the branching ratios. The rate differences for B+→π+π+π- and B+→K+ K+ K- satisfy the relation between ΔS = 0 and ΔS = 1 as well, but the other two do not, with the CP asymmetries having different signs than expected. In this paper, we study how to include momentum dependent and also SU(3) breaking effects on these decays to explain experimental data. We find that by including only the lowest order derivative terms, in the SU(3) limit, the decay patterns cannot be explained. Large SU(3) breaking effects are needed to explain the data.

FCNC PROCESS IN B DECAY AND THE VECTOR MESON DOMINANCE

1999 ◽  
Vol 14 (25) ◽  
pp. 1701-1712
Author(s):  
SURATH KUMAR BISWAS ◽  
V. P. GAUTAM
Keyword(s):  
Vector Meson ◽  
Short Distance ◽  
Distance Effect ◽  
Vector Meson Dominance ◽  
Matrix Elements ◽  
Long Distance ◽  
Inclusive Decays ◽  
The Matrix ◽  
Working Out

We investigate how the vector meson dominance affects the O(αs) virtual corrections in addition to the bremsstrahlung correction while working out the matrix elements for b→sγ and b→ dγ decays. Long-distance effect alone is not appreciable but it is a good supplement to the short-distance contribution. We obtain better results for the inclusive decays.

An isospin-mixed triplet in 44Ti

1980 ◽  
Vol 58 (9) ◽  
pp. 1360-1366 ◽  
Author(s):  
W. R. Dixon ◽  
R. S. Storey ◽  
J. J. Simpson
Keyword(s):  
Experimental Data ◽  
Ground State ◽  
Gamma Ray ◽  
Branching Ratios ◽  
Proton Decay ◽  
The Other ◽  
Angular Distributions ◽  
Matrix Elements ◽  
Quantitative Estimates

Three levels in 44Ti at energies of 9215 ± 2, 9227 ± 2, and 9239 ± 2 keV have been studied in the 40Ca(α,γ) reaction. Gamma-ray branching ratios, angular distributions, and transition strengths have been measured for each level. Proton decay strengths have also been determined. Each level is assigned Jπ = 2+. The level at 9227 keV must be predominantly T = 1 because of its strong M1 decays, while the other two levels are believed to be predominantly T = 0 because of their stronger E2 transitions to the ground state. Treating the three levels as an isospin-mixed triplet gives a consistent interpretation for all the experimental data, and allows quantitative estimates to be made of the amount of isospin mixing and of the magnitude of the isovector matrix elements.

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