scholarly journals Study on the Resonant Parameters of Y (4220) and Y (4390)

2018 ◽  
Vol 2018 ◽  
pp. 1-7
Author(s):  
Jielei Zhang ◽  
Limin Yuan ◽  
Rumin Wang
Keyword(s):  
Cross Sections ◽  
Leptonic Decay ◽  
Decay Widths ◽  
The Cross ◽  
Lower Limits

Many vector charmonium-like states have been reported recently in the cross sections of e+e-→ωχc0, π+π-hc, π+π-J/ψ, π+π-ψ(3686), and π+D0D⁎-+c.c. To better understand the nature of these states, a combined fit is performed to these cross sections by using three resonances Y(4220), Y(4390), and Y(4660). The resonant parameters for the three resonances are obtained. We emphasize that two resonances Y(4220) and Y(4390) are sufficient to explain these cross sections below 4.6 GeV. The lower limits of Y(4220) and Y(4390)’s leptonic decay widths are also determined to be (36.4±2.0±4.2) and (123.8±6.5±9.0) eV.

Resonant parameters of Y(4390)

2017 ◽  
Vol 32 (33) ◽  
pp. 1750184 ◽  
Author(s):  
Jielei Zhang ◽  
Limin Yuan
Keyword(s):  
Lower Limit ◽  
Decay Width ◽  
Cross Sections ◽  
Leptonic Decay ◽  
Decay Modes ◽  
S Parameters ◽  
The Cross

The cross-sections of [Formula: see text] and [Formula: see text] have been measured by BESIII experiment. A new resonance [Formula: see text] is observed in the two decay modes. A combined fit is performed to the two cross-sections. [Formula: see text]’s parameters are determined to be [Formula: see text], [Formula: see text], where the first uncertainties are statistical and the second systematic. The ratio [Formula: see text] is also obtained and it indicates that [Formula: see text]’s main decay modes maybe [Formula: see text]. We determine the lower limit of its leptonic decay width of around 150 eV, which can be compared with the theoretical expectations of different models. These information may help in understanding the nature of this state.

Combined fit to the cross-sections of e+e−→ π+π−ψ(3686) and e+e−→ Λc+Λc−

2018 ◽  
Vol 33 (03) ◽  
pp. 1850020 ◽  
Author(s):  
Jielei Zhang ◽  
Limin Yuan
Keyword(s):  
Lower Limit ◽  
Decay Width ◽  
Decay Mode ◽  
Cross Sections ◽  
Leptonic Decay ◽  
Decay Modes ◽  
S Parameters ◽  
Belle Experiment ◽  
The Cross

The cross-sections of [Formula: see text] and [Formula: see text] have been measured by Belle experiment. A resonance [Formula: see text] is observed in [Formula: see text] decay mode, while another resonance [Formula: see text] is observed in [Formula: see text] decay mode. The two resonances [Formula: see text] and [Formula: see text]’s parameters are consistent with each other, so a combined fit is performed to the two cross-sections assuming [Formula: see text] and [Formula: see text] are same resonance. [Formula: see text]’s parameters are determined to be [Formula: see text], [Formula: see text], where the first uncertainties are statistical and the second systematic. The ratio [Formula: see text] is also obtained and it indicates that [Formula: see text]’s main decay modes may be [Formula: see text]. We determine the lower limit of its leptonic decay width of around 40 eV, which can be compared with the theoretical expectations of different models.

The cross sections for different channels in heavy ion nuclear reactions

1971 ◽  
Vol 32 (1) ◽  
pp. 7-9 ◽  
Author(s):  
J. Galin ◽  
D. Guerreau ◽  
M. Lefort ◽  
X. Tarrago
Keyword(s):  
Cross Sections ◽  
Nuclear Reactions ◽  
Heavy Ion ◽  
The Cross

Experimental Studies Of Multilayer Glass Structures On Compression, Compression With Bending And Simple Bending

2019 ◽  
pp. 22-30
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Applied Load ◽  
Experimental Studies ◽  
Strength Properties ◽  
Research Topic ◽  
Normative Values ◽  
Laminated Glass ◽  
The Cross ◽  
Experimental Values

The work of multilayer glass structures for central and eccentric compression and bending are considered. The substantiation of the chosen research topic is made. The description and features of laminated glass for the structures investigated, their characteristics are presented. The analysis of the results obtained when testing for compression, compression with bending, simple bending of models of columns, beams, samples of laminated glass was made. Overview of the types and nature of destruction of the models are presented, diagrams of material operation are constructed, average values of the resistance of the cross-sections of samples are obtained, the table of destructive loads is generated. The need for development of a set of rules and guidelines for the design of glass structures, including laminated glass, for bearing elements, as well as standards for testing, rules for assessing the strength, stiffness, crack resistance and methods for determining the strength of control samples is emphasized. It is established that the strength properties of glass depend on the type of applied load and vary widely, and significantly lower than the corresponding normative values of the strength of heat-strengthened glass. The effect of the connecting polymeric material and manufacturing technology of laminated glass on the strength of the structure is also shown. The experimental values of the elastic modulus are different in different directions of the cross section and in the direction perpendicular to the glass layers are two times less than along the glass layers.

scholarly journals Total cross sections of eγ → $$ eX\overline{X} $$ processes with X = μ, γ, e via multiloop methods

2021 ◽  
Vol 2021 (1) ◽  
Author(s):  
Roman N. Lee ◽  
Alexey A. Lyubyakin ◽  
Vyacheslav A. Stotsky
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Elliptic Integral ◽  
High Energy ◽  
Calculation Methods ◽  
Complete Elliptic Integral ◽  
Total Cross Sections ◽  
Multiloop Calculation ◽  
The Cross ◽  
Analytical Expressions

Abstract Using modern multiloop calculation methods, we derive the analytical expressions for the total cross sections of the processes e−γ →$$ {e}^{-}X\overline{X} $$ e − X X ¯ with X = μ, γ or e at arbitrary energies. For the first two processes our results are expressed via classical polylogarithms. The cross section of e−γ → e−e−e+ is represented as a one-fold integral of complete elliptic integral K and logarithms. Using our results, we calculate the threshold and high-energy asymptotics and compare them with available results.

scholarly journals Asymptotic Behavior of Stable Structures Made of Beams

2021 ◽  
Author(s):  
Georges Griso ◽  
Larysa Khilkova ◽  
Julia Orlik ◽  
Olena Sivak
Keyword(s):  
Asymptotic Behavior ◽  
Cross Section ◽  
Cross Sections ◽  
Linear Elasticity ◽  
Circular Cross Section ◽  
Linear Elasticity Theory ◽  
Linear Elastic ◽  
The Cross ◽  
Small Rotation ◽  
Stable Structures

AbstractIn this paper, we study the asymptotic behavior of an $\varepsilon $ ε -periodic 3D stable structure made of beams of circular cross-section of radius $r$ r when the periodicity parameter $\varepsilon $ ε and the ratio ${r/\varepsilon }$ r / ε simultaneously tend to 0. The analysis is performed within the frame of linear elasticity theory and it is based on the known decomposition of the beam displacements into a beam centerline displacement, a small rotation of the cross-sections and a warping (the deformation of the cross-sections). This decomposition allows to obtain Korn type inequalities. We introduce two unfolding operators, one for the homogenization of the set of beam centerlines and another for the dimension reduction of the beams. The limit homogenized problem is still a linear elastic, second order PDE.

ISOSPIN DECOMPOSITION OF pp → NNππ CROSS SECTIONS — DO WE SEE A SIGN OF Δ(1600) EXCITATION IN THE nnπ+π+ CHANNEL?

2009 ◽  
Vol 24 (02n03) ◽  
pp. 450-453
Author(s):  
◽  
T. SKORODKO ◽  
M. BASHKANOV ◽  
D. BOGOSLOWSKY ◽  
H. CALÉN ◽  
...  
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Differential Cross ◽  
Pion Production ◽  
Significant Contribution ◽  
Differential Cross Sections ◽  
Pp Collisions ◽  
Theoretical Predictions ◽  
Order Of Magnitude ◽  
The Cross

The two-pion production in pp-collisions has been investigated in exclusive measurements from threshold up to Tp = 1.36 GeV . Total and differential cross sections have been obtained for the channels pnπ+π0, ppπ+π-, ppπ0π0 and also nnπ+π+. For intermediate incident energies Tp > 1 GeV , i.e. in the region, which is beyond the Roper excitation but at the onset of ΔΔ excitation the total ppπ0π0 cross section falls behind theoretical predictions by as much as an order of magnitude near 1.2 GeV, whereas the nnπ+π+ cross section is a factor of five larger than predicted. A model-unconstrained isospin decompostion of the cross section points to a significant contribution of an isospin 3/2 resonance other than the Δ(1232). As a possible candidate the Δ(1600) is discussed.

Improved Diffuser/Volute Combinations for Centrifugal Compressors

2008 ◽  
Vol 130 (1) ◽  
Author(s):  
T. Steglich ◽  
J. Kitzinger ◽  
J. R. Seume ◽  
R. A. Van den Braembussche ◽  
J. Prinsier
Keyword(s):  
Cross Sections ◽  
Pressure Ratio ◽  
Pressure Rise ◽  
Outer Radius ◽  
Inner Radius ◽  
Pressure Pipeline ◽  
The Cross ◽  
Improved Performance ◽  
High Pressure Pipeline ◽  
Original Configuration

Internal volutes have a constant outer radius, slightly larger than the diffuser exit radius, and the circumferential increase of the cross section is accommodated by a decrease of the inner radius. They allow the design of compact radial compressors and hence are very attractive for turbochargers and high-pressure pipeline compressors, where small housing diameters have a favorable impact on weight and cost. Internal volutes, however, have higher losses and lower pressure rise than external ones, in which the center of the cross sections is located at a larger radius than the diffuser exit. This paper focuses on the improvement of the internal volute performance by taking into account the interaction between the diffuser and the volute. Two alternative configurations with enhanced aerodynamic performance are presented. The first one features a novel, nonaxisymmetric diffuser̸internal volute combination. It demonstrates an increased pressure ratio and lower loss over most of the operating range at all rotational speeds compared with a symmetric diffuser̸internal volute combination. The circumferential pressure distortion at off design operation is slightly larger than in the original configuration with a concentric vaneless diffuser. Alternatively, a parallel-walled diffuser with low-solidity vanes and an internal volute allows a reduction of the unsteady load on the impeller and an improved performance, approaching that of a vaneless concentric diffuser with a large external volute.

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