scholarly journals XYZ-like spectra from Laplace sum rule at N2LO in the chiral limit

2016 ◽  
Vol 31 (36) ◽  
pp. 1650196 ◽  
Author(s):  
R. Albuquerque ◽  
S. Narison ◽  
F. Fanomezana ◽  
A. Rabemananjara ◽  
D. Rabetiarivony ◽  
...  
Keyword(s):  
Sum Rules ◽  
Chiral Limit ◽  
Operator Product ◽  
Theoretical Studies ◽  
Leading Order ◽  
Spectral Functions ◽  
Decay Constants ◽  
Heavy Quark Mass ◽  
The Masses ◽  
Spectral Sum Rules

We present new compact integrated expressions of QCD spectral functions of heavy-light molecules and four-quark [Formula: see text]-like states at lowest order (LO) of perturbative (PT) QCD and up to [Formula: see text] condensates of the Operator Product Expansion (OPE). Then, by including up to next-to-next leading order (N2LO) PT QCD corrections, which we have estimated by assuming the factorization of the four-quark spectral functions, we improve previous LO results from QCD spectral sum rules (QSSR), on the [Formula: see text]-like masses and decay constants which suffer from the ill-defined heavy quark mass. PT N3LO corrections are estimated using a geometric growth of the PT series and are included in the systematic errors. Our optimal results based on stability criteria are summarized in Tables 11–14 and compared, in Sec. 10, with experimental candidates and some LO QSSR results. We conclude that the masses of the [Formula: see text] observed states are compatible with (almost) pure [Formula: see text], [Formula: see text] molecule or/and four-quark states. The ones of the [Formula: see text], [Formula: see text] molecule/four-quark states are about 1.5 GeV above the [Formula: see text] mesons experimental candidates and hadronic thresholds. We also find that the couplings of these exotics to the associated interpolating currents are weaker than that of ordinary [Formula: see text] mesons [Formula: see text] and may behave numerically as [Formula: see text] (respectively [Formula: see text]) for the [Formula: see text], [Formula: see text] (respectively [Formula: see text], [Formula: see text]) states which can stimulate further theoretical studies of these decay constants.

scholarly journals XYZ-SU3 breakings from Laplace sum rules at higher orders

2018 ◽  
Vol 33 (16) ◽  
pp. 1850082 ◽  
Author(s):  
R. Albuquerque ◽  
S. Narison ◽  
D. Rabetiarivony ◽  
G. Randriamanatrika
Keyword(s):  
Sum Rules ◽  
Chiral Limit ◽  
Axial Vector ◽  
Operator Product ◽  
Leading Order ◽  
Spectral Functions ◽  
Quark State ◽  
Future Data ◽  
The Masses ◽  
Spectral Sum Rules

We present new compact integrated expressions of SU3 breaking corrections to QCD spectral functions of heavy–light molecules and four-quark [Formula: see text]-like states at lowest order (LO) of perturbative (PT) QCD and up to [Formula: see text] condensates of the Operator Product Expansion (OPE). Including next-to-next-to-leading order (N2LO) PT corrections in the chiral limit and next-to-leading order (NLO) SU3 PT corrections, which we have estimated by assuming the factorization of the four-quark spectral functions, we improve previous LO results for the [Formula: see text]-like masses and decay constants from QCD spectral sum rules (QSSR). Systematic errors are estimated from a geometric growth of the higher order PT corrections and from some partially known [Formula: see text] nonperturbative contributions. Our optimal results, based on stability criteria, are summarized in Tables 18–21 while the [Formula: see text] and [Formula: see text] channels are compared with some existing LO results in Table 22. One can note that, in most channels, the SU3 corrections on the meson masses are tiny: [Formula: see text] (respectively [Formula: see text]) for the [Formula: see text] (respectively [Formula: see text])-quark channel but can be large for the couplings ([Formula: see text]). Within the lowest dimension currents, most of the [Formula: see text] and [Formula: see text] states are below the physical thresholds while our predictions cannot discriminate a molecule from a four-quark state. A comparison with the masses of some experimental candidates indicates that the [Formula: see text] [Formula: see text] might have a large [Formula: see text] molecule component while an interpretation of the [Formula: see text] candidates as four-quark ground states is not supported by our findings. The [Formula: see text] [Formula: see text] and [Formula: see text] are compatible with the [Formula: see text], [Formula: see text] molecules and/or with the axial-vector [Formula: see text] four-quark ground state. Our results for the [Formula: see text], [Formula: see text] and for different beauty states can be tested in the future data. Finally, we revisit our previous estimates1 for the [Formula: see text] and [Formula: see text] and present new results for the [Formula: see text].

scholarly journals Decay constants and masses of light tensor mesons (JP = 2+)

2015 ◽  
Vol 30 (18n19) ◽  
pp. 1550106
Author(s):  
R. Khosravi ◽  
D. Hatami
Keyword(s):  
Standard Model ◽  
Operator Product Expansion ◽  
Sum Rules ◽  
Operator Product ◽  
Qcd Sum Rules ◽  
Decay Constants ◽  
Quantum Numbers ◽  
The Standard Model ◽  
The Masses

The masses and decay constants of the light tensor mesons were calculated with quantum numbers [Formula: see text] in the framework of the QCD sum rules in the standard model. The non perturbative contributions up to dimension-5 are considered as important terms of the operator product expansion.

scholarly journals Thermal Properties of Light Tensor Mesons via QCD Sum Rules

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
K. Azizi ◽  
A. Türkan ◽  
E. Veli Veliev ◽  
H. Sundu
Keyword(s):  
Thermal Properties ◽  
Finite Temperature ◽  
Sum Rules ◽  
Temperature Dependent ◽  
Qcd Sum Rules ◽  
Continuum Threshold ◽  
Decay Constants ◽  
Good Consistency ◽  
Theoretical Predictions ◽  
The Masses

The thermal properties off2(1270),a2(1320), andK2*(1430) light tensor mesons are investigated in the framework of QCD sum rules at finite temperature. In particular, the masses and decay constants of the light tensor mesons are calculated taking into account the new operators appearing at finite temperature. The numerical results show that, at the point at which the temperature-dependent continuum threshold vanishes, the decay constants decrease with amount of (70–85)% compared to their vacuum values, while the masses diminish about (60–72)% depending on the kinds of the mesons under consideration. The results obtained at zero temperature are in good consistency with the experimental data as well as the existing theoretical predictions.

scholarly journals Analysis of the heavy quarkonium states hc and hb with QCD sum rules

2014 ◽  
Vol 29 ◽  
pp. 1460233
Author(s):  
Zhi-Gang Wang ◽  
Shu-Yuan Guo
Keyword(s):  
Experimental Data ◽  
Sum Rules ◽  
P Wave ◽  
Heavy Quarkonium ◽  
Qcd Sum Rules ◽  
Decay Constants ◽  
Spin Singlet ◽  
Structure Formula ◽  
Quark Structure ◽  
The Masses

In this article, we take the tensor currents [Formula: see text] to interpolate the P-wave spin-singlet heavy quarkonium states hQ, and study the masses and decay constants with the Borel sum rules and moments sum rules. The masses and decay constants from the Borel sum rules and moments sum rules are consistent with each other, the masses are also consistent with the experimental data. The heavy quarkonium states hQ couple potentially to the tensor currents [Formula: see text], and have the quark structure ϵijkξ†σkζ besides the quark structure [Formula: see text].

scholarly journals Mass Spectra and Decay Constants of Heavy-Light Mesons: A Case Study of QCD Sum Rules and Quark Model

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Halil Mutuk
Keyword(s):  
Quark Model ◽  
Mass Spectra ◽  
Sum Rules ◽  
Theoretical Studies ◽  
Sum Rule ◽  
Decay Constants ◽  
Oscillator Wave Function ◽  
Light Mesons ◽  
Harmonic Oscillator Wave Function

We visited mass spectra and decay constants of pseudoscalar and vector heavy-light mesons (B, Bs, D, and DS) in the framework of QCD sum rule and quark model. The harmonic oscillator wave function was used in quark model while a simple interpolating current was used in QCD sum rule calculation. We obtained good results in accordance with the available experimental data and theoretical studies.

scholarly journals Large-Nc masses of light mesons from QCD sum rules for nonlinear radial Regge trajectories

2018 ◽  
Vol 33 (12) ◽  
pp. 1850069 ◽  
Author(s):  
S. S. Afonin ◽  
T. D. Solomko
Keyword(s):  
Sum Rules ◽  
Linear Part ◽  
Operator Product ◽  
Regge Trajectories ◽  
Pseudoscalar Mesons ◽  
Light Vector ◽  
Original Analysis ◽  
Point Correlation ◽  
Spectral Sum Rules ◽  
The Given

The large-[Formula: see text] masses of light vector, axial, scalar and pseudoscalar mesons are calculated from QCD spectral sum rules for a particular ansatz interpolating the radial Regge trajectories. The ansatz includes a linear part plus exponentially degreasing corrections to the meson masses and residues. The form of corrections was proposed some time ago for consistency with analytical structure of Operator Product Expansion of the two-point correlation functions. We revised that original analysis and found the second solution for the proposed sum rules. The given solution describes better the spectrum of vector and axial mesons.

scholarly journals Nature of the X(5568) — A critical Laplace sum rule analysis at N2LO

2016 ◽  
Vol 31 (17) ◽  
pp. 1650093 ◽  
Author(s):  
R. Albuquerque ◽  
S. Narison ◽  
A. Rabemananjara ◽  
D. Rabetiarivony
Keyword(s):  
Quark Mass ◽  
Continuum Threshold ◽  
Sum Rule ◽  
Heavy Quark Mass ◽  
Quark State ◽  
Rule Analysis ◽  
The One ◽  
The Masses ◽  
Exotic Hadrons ◽  
Spectral Sum Rules

We scrutinize recent QCD spectral sum rules (QSSR) results to lowest order (LO) predicting the masses of the [Formula: see text] molecule and [Formula: see text] four-quark states. We improve these results by adding NLO and N2LO corrections to the PT contributions giving a more precise meaning on the [Formula: see text]-quark mass definition used in the analysis. We extract our optimal predictions using Laplace sum rule (LSR) within the standard stability criteria versus the changes of the external free parameters ([Formula: see text]-sum rule variable, [Formula: see text] continuum threshold and subtraction constant [Formula: see text]). The smallness of the higher order PT corrections justifies (a posteriori) the LO order results ⊕ the uses of the ambiguous heavy quark mass to that order. However, our predicted spectra in the range [Formula: see text] MeV, summarized in Table 7, for exotic hadrons built with four different flavors [Formula: see text], do not support some previous interpretations of the D0 candidate,1 [Formula: see text], as a pure molecule or a four-quark state. If experimentally confirmed, it could result from their mixing with an angle: [Formula: see text]. One can also scan the region [Formula: see text] MeV (where the [Formula: see text] might be a good candidate) and the one [Formula: see text] MeV for detecting these [Formula: see text] and [Formula: see text] unmixed exotic hadrons (if any) via, eventually, their radiative or [Formula: see text][Formula: see text]+[Formula: see text]hadrons decays.

BARYONIC SUM RULES IN THE NEXT-TO-LEADING ORDER IN αs

1991 ◽  
Vol 06 (11) ◽  
pp. 2025-2034 ◽  
Author(s):  
A.A. OVCHINNIKOV ◽  
A.A. PIVOVAROV ◽  
L.R. SURGULADZE
Keyword(s):  
Experimental Data ◽  
Operator Product Expansion ◽  
Sum Rules ◽  
Operator Product ◽  
Leading Order ◽  
Perturbative Corrections

The perturbative corrections of order αs to the coefficient functions of the operator product expansion for the baryonic correlator are calculated. These corrections change considerably the numerical values of the mass and residue for the proton extracted from the sum rules and improve the agreement between the theoretical estimates and experimental data.

scholarly journals Radiative decays of heavy-light mesons and the $$ {f}_{H,{H}^{\ast },{H}_1}^{(T)} $$ decay constants

2021 ◽  
Vol 2021 (9) ◽  
Author(s):  
Ben Pullin ◽  
Roman Zwicky
Keyword(s):  
Sum Rules ◽  
Form Factors ◽  
Radiative Decays ◽  
Matrix Elements ◽  
Leading Order ◽  
Sum Rule ◽  
Decay Constants ◽  
Leptonic Decays ◽  
Shell Matrix ◽  
First Time

Abstract The on-shell matrix elements, or couplings $$ {g}_{H{H}^{\ast}\left({H}_1\right)\upgamma} $$ g H H ∗ H 1 γ , describing the $$ B{(D)}_q^{\ast } $$ B D q ∗ → B(D)qγ and B1q → Bqγ (q = u, d, s) radiative decays, are determined from light-cone sum rules at next-to-leading order for the first time. Two different interpolating operators are used for the vector meson, providing additional robustness to our results. For the D*-meson, where some rates are experimentally known, agreement is found. The couplings are of additional interest as they govern the lowest pole residue in the B(D) → γ form factors which in turn are connected to QED-corrections in leptonic decays B(D) → ℓ$$ \overline{\nu} $$ ν ¯ . Since the couplings and residues are related by the decay constants $$ {f}_{H^{\ast}\left({H}_1\right)} $$ f H ∗ H 1 and $$ {f}_{H^{\ast}\left({H}_1\right)}^T $$ f H ∗ H 1 T , we determine them at next-leading order as a by-product. The quantities $$ \left\{{f}_{H^{\ast}}^T,{f}_{H_1}^T\right\} $$ f H ∗ T f H 1 T have not previously been subjected to a QCD sum rule determination. All results are compared with the existing experimental and theoretical literature.

scholarly journals The ground states and the first radially excited states of D-wave vector ρ and ϕ mesons

2021 ◽  
Author(s):  
Guo-Liang Yu ◽  
Zhi-Gang Wang ◽  
Xiu-Wu Wang ◽  
Hui-Juan Wang
Keyword(s):  
Excited States ◽  
Wave Vector ◽  
Operator Product Expansion ◽  
Sum Rules ◽  
Ground States ◽  
Operator Product ◽  
Decay Constants ◽  
Vector Formula ◽  
Vacuum Condensates ◽  
D Wave

In this paper, we first derive two QCD sum rules QCDSR I and QCDSR II which are, respectively, used to extract observable quantities of the ground states and the first radially excited states of the D-wave vector [Formula: see text] and [Formula: see text] mesons. In our calculations, we consider the contributions of vacuum condensates up to dimension-7 in the operator product expansion. The predicted masses for [Formula: see text] [Formula: see text] meson and [Formula: see text] [Formula: see text] meson are consistent well with the experimental data of [Formula: see text]([Formula: see text]) and [Formula: see text]([Formula: see text]), respectively. Besides, our analysis indicates that it is reliable to assign the recent reported [Formula: see text]([Formula: see text]) state as the [Formula: see text] [Formula: see text] meson. Finally, we obtain the decay constants of these states with QCDSR I and QCDSR II. These predictions are helpful not only to reveal the structure of the newly observed [Formula: see text]([Formula: see text]) state, but also to establish [Formula: see text] meson and [Formula: see text] meson families.

Sign in / Sign up

Export Citation Format

Share Document