ON NONLEPTONIC Σ+ → pπ0 DECAY IN THE EFFECTIVE QUARK MODEL WITH CHIRAL U(3) × U(3) SYMMETRY

2007 ◽  
Vol 22 (25) ◽  
pp. 4651-4666
Author(s):  
A. YA. BERDNIKOV ◽  
YA. A. BERDNIKOV ◽  
M. FABER ◽  
A. N. IVANOV ◽  
V. A. IVANOVA ◽  
...  
Keyword(s):  
Experimental Data ◽  
Quark Model ◽  
Partial Width ◽  
P Wave ◽  
Nonleptonic Decay ◽  
S Wave ◽  
Theoretical Results

Within the effective quark model with chiral U (3) × U (3) symmetry we calculate the S-wave and P-wave amplitudes of the nonleptonic decay Σ+ → pπ0, the partial width and the dynamical polarization of the proton in the dependence on the polarization of the Σ+-hyperon. The theoretical results agree well with the experimental data.

ON NONLEPTONIC DECAYS OF THE Λ0-HYPERON IN THE EFFECTIVE QUARK MODEL WITH CHIRAL U(3)×U(3) SYMMETRY

2007 ◽  
Vol 22 (10) ◽  
pp. 1835-1847 ◽  
Author(s):  
A. YA. BERDNIKOV ◽  
YA. A. BERDNIKOV ◽  
M. FABER ◽  
A. N. IVANOV ◽  
V. A. IVANOVA ◽  
...  
Keyword(s):  
Experimental Data ◽  
Quark Model ◽  
Rest Frame ◽  
Laboratory Frame ◽  
Decay Rates ◽  
P Wave ◽  
Angular Distributions ◽  
S Wave ◽  
Nonleptonic Decays ◽  
Theoretical Results

Within the effective quark model with chiral U (3) × U (3) symmetry we calculate the S-wave and P-wave amplitudes and the partial widths of the nonleptonic decays of the Λ0-hyperon, Λ0 → pπ- and Λ0 → nπ0. The theoretical results agree well with the experimental data. The angular distributions of the decay rates in dependence on the polarizations of baryons are analyzed both in the laboratory frame and in the rest frame of the Λ0-hyperon.

Seismic reflectivity of hydraulic fractures approximated by thin fluid layers

Geophysics ◽  
2013 ◽  
Vol 78 (4) ◽  
pp. T79-T87 ◽  
Author(s):  
A. Oelke ◽  
D. Alexandrov ◽  
I. Abakumov ◽  
S. Glubokovskikh ◽  
R. Shigapov ◽  
...  
Keyword(s):  
Analytical Solutions ◽  
Fluid Layer ◽  
Synthetic Data ◽  
P Wave ◽  
Hydraulic Fractures ◽  
Reflection Coefficients ◽  
S Wave ◽  
Reservoir Properties ◽  
Thin Fluid ◽  
Theoretical Results

We have analyzed the angle-dependent reflectivity of microseismic wavefields at a hydraulic fracture, which we modeled as an ideal thin fluid layer embedded in an elastic, isotropic solid rock. We derived full analytical solutions for the reflections of an incident P-wave, the P-P and P-S reflection coefficients, as well as for an incident S-wave, and the S-S and S-P reflection coefficients. The rather complex analytical solutions were then approximated and we found that these zero-thickness limit approximations are in good agreement with the linear slip model, representing a fracture at slip contact. We compared the analytical solutions for the P-P reflections with synthetic data that were derived using finite-difference modeling and found that the modeling confirmed our theoretical results. For typical parameters of microseismic monitoring by hydraulic fracturing, e.g., a layer thickness of [Formula: see text] and frequencies of [Formula: see text], the reflection coefficients depend on the Poisson’s ratio. Furthermore, the reflection coefficients of an incident S-wave are remarkably high. Theoretical results suggested that it is feasible to image hydraulic fractures using microseismic events as a source and to solve the inverse problem, that is, to interpret reflection coefficients extracted from microseismic data in terms of reservoir properties.

scholarly journals Study of baryon octet charge form factors in perturbative chiral quark model

2014 ◽  
Vol 29 ◽  
pp. 1460252
Author(s):  
X. Y. Liu ◽  
K. Khosonthongkee ◽  
A. Limphirat ◽  
Y. Yan
Keyword(s):  
Experimental Data ◽  
Wave Function ◽  
Quark Model ◽  
Form Factors ◽  
Baryon Octet ◽  
Chiral Quark Model ◽  
Charge Form ◽  
Quark Wave Function ◽  
Theoretical Results ◽  
Good Agreement

The charge form factors of baryon octet are studied in the perturbative chiral quark model (PCQM). The relativistic quark wave function is extracted by fitting the theoretical results of the nucleon charge form factors to the experimental data and the predetermined quark wave function is applied to study the charge form factors of other octet baryons. The PCQM results are found, based on the predetermined quark wave function, in good agreement with the experimental data.

NEW HADRON STATES

2008 ◽  
Vol 17 (02) ◽  
pp. 283-322 ◽  
Author(s):  
SHI-LIN ZHU
Keyword(s):  
Quark Model ◽  
P Wave ◽  
Underlying Structure ◽  
S Wave ◽  
Charmed Mesons ◽  
Exotic Mesons ◽  
Hadron Spectroscopy ◽  
Threshold Enhancement ◽  
Dynamical Lattice ◽  
Decay Threshold

In the past four years we have witnessed the renaissance of the hadron spectroscopy. Many interesting new hadron states were discovered experimentally, some of which do not fit into the quark model easily. I will give a concise overview of these states and their possible interpretations. Topics covered in this review are: (1) candidates of new light hadrons including [Formula: see text] threshold enhancement, X(1835), X(1576), f0(1810), recent candidates of the 1-+ exotic mesons, Y(2175), [Formula: see text] threshold enhancement etc. (2) charmed mesons including p-wave non-strange charmed mesons, Dsj(2317) and Dsj(2460), recent candidates of higher excited charmed mesons, Dsj(2632) etc. (3) charmonium and charmonium-like states such as X(3872), Y(4260), X(3940), Y(3940), Z(3930) etc. The effect from the nearby S-wave open channels on the quark model spectrum above or near strong decay threshold is emphasized. Dynamical lattice simulations of DK and [Formula: see text] scattering and the extraction of their phase shifts may help resolve the underlying structure of Dsj(2317), Dsj(2460) and X(3872).

DESCRIPTION OF SU(3) S-WAVE AND P-WAVE BARYONS

2003 ◽  
Vol 18 (02n06) ◽  
pp. 362-365
Author(s):  
MIKITO FURUICHI ◽  
KIYOTAKA SHIMIZU ◽  
Sachiko Takeuchi
Keyword(s):  
Quark Model ◽  
Excited States ◽  
Negative Parity ◽  
Nucleon Resonance ◽  
P Wave ◽  
Meson Exchange ◽  
Exchange Potential ◽  
Chiral Quark Model ◽  
S Wave ◽  
Quark System

We investigate the structure of the SU(3) octet and decuplet baryons employing a constituent chiral quark model. We study the ground, s-wave and p-wave excited states of the three-quark system with many range gaussian bases. The method, which we employ here, is shown to work quite well in describing the structure of the SU(3) s-wave and p-wave baryons. It is found that the mass differences between positive and negative parity states are well reproduced. It is also found that the pseudoscalar (ps) meson exchange potential plays a very important role in describing the mass of the nucleon resonance N*(1440) (roper). We also discuss how the semirelativistic approach works in the chiral quark model, and how to treat the potential terms in the semirelativistic approach.

scholarly journals Post-collisional mantle delamination in the Dinarides implied from staircases of Oligo-Miocene uplifted marine terraces

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Philipp Balling ◽  
Christoph Grützner ◽  
Bruno Tomljenović ◽  
Wim Spakman ◽  
Kamil Ustaszewski
Keyword(s):  
Balkan Peninsula ◽  
Receiver Functions ◽  
P Wave ◽  
S Wave ◽  
Slab Geometry ◽  
Surface Uplift ◽  
River Incision ◽  
Marine Terraces ◽  
Convergence System ◽  
Internal Dinarides

AbstractThe Dinarides fold-thrust belt on the Balkan Peninsula resulted from convergence between the Adriatic and Eurasian plates since Mid-Jurassic times. Under the Dinarides, S-wave receiver functions, P-wave tomographic models, and shear-wave splitting data show anomalously thin lithosphere overlying a short down-flexed slab geometry. This geometry suggests a delamination of Adriatic lithosphere. Here, we link the evolution of this continental convergence system to hitherto unreported sets of extensively uplifted Oligocene–Miocene (28–17 Ma) marine terraces preserved at elevations of up to 600 m along the Dinaric coastal range. River incision on either side of the Mediterranean-Black Sea drainage divide is comparable to the amounts of terrace uplift. The preservation of the uplifted terraces implies that the most External Dinarides did not experience substantial deformation other than surface uplift in the Neogene. These observations and the contemporaneous emplacement of igneous rocks (33–22 Ma) in the internal Dinarides suggest that the Oligo-Miocene orogen-wide uplift was driven by post-break-off delamination of the Adriatic lithospheric mantle, this was followed by isostatic readjustment of the remaining crust. Our study details how lithospheric delamination exerts an important control on crustal deformation and that its crustal signature and geomorphic imprint can be preserved for millions of years.

scholarly journals S-wave experiments for the exploration of a deep geothermal carbonate reservoir in the German Molasse Basin

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Britta Wawerzinek ◽  
Hermann Buness ◽  
Hartwig von Hartmann ◽  
David C. Tanner
Keyword(s):  
Upper Jurassic ◽  
Carbonate Reservoir ◽  
P Wave ◽  
Seismic Survey ◽  
Seismic Exploration ◽  
Molasse Basin ◽  
S Wave ◽  
Induced Earthquakes ◽  
Conversion Point ◽  
Facies Classification

AbstractThere are many successful geothermal projects that exploit the Upper Jurassic aquifer at 2–3 km depth in the German Molasse Basin. However, up to now, only P-wave seismic exploration has been carried out. In an experiment in the Greater Munich area, we recorded S-waves that were generated by the conventional P-wave seismic survey, using 3C receivers. From this, we built a 3D volume of P- to S-converted (PS) waves using the asymptotic conversion point approach. By combining the P-volume and the resulting PS-seismic volume, we were able to derive the spatial distribution of the vp/vs ratio of both the Molasse overburden and the Upper Jurassic reservoir. We found that the vp/vs ratios for the Molasse units range from 2.0 to 2.3 with a median of 2.15, which is much higher than previously assumed. This raises the depth of hypocenters of induced earthquakes in surrounding geothermal wells. The vp/vs ratios found in the Upper Jurassic vary laterally between 1.5 and 2.2. Since no boreholes are available for verification, we test our results against an independently derived facies classification of the conventional 3D seismic volume and found it correlates well. Furthermore, we see that low vp/vs ratios correlate with high vp and vs velocities. We interpret the latter as dolomitized rocks, which are connected with enhanced permeability in the reservoir. We conclude that 3C registration of conventional P-wave surveys is worthwhile.

Inverse design of layered periodic wave barriers based on deep learning

2021 ◽  
pp. 146442072110168
Author(s):  
Chen-Xu Liu ◽  
Gui-Lan Yu
Keyword(s):  
Deep Learning ◽  
Activation Function ◽  
Periodic Wave ◽  
P Wave ◽  
Soil Parameters ◽  
S Wave ◽  
Output Frequency ◽  
Great Generality ◽  
Typical Range ◽  
Deep Learning Model

This study presents an approach based on deep learning to design layered periodic wave barriers with consideration of typical range of soil parameters. Three cases are considered where P wave and S wave exist separately or simultaneously. The deep learning model is composed of an autoencoder with a pretrained decoder which has three branches to output frequency attenuation domains for three different cases. A periodic activation function is used to improve the design accuracy, and condition variables are applied in the code layer of the autoencoder to meet the requirements of practical multi working conditions. Forty thousand sets of data are generated to train, validate, and test the model, and the designed results are highly consistent with the targets. The presented approach has great generality, feasibility, rapidity, and accuracy on designing layered periodic wave barriers which exhibit good performance in wave suppression in targeted frequency range.

The Compliance of Solid, Wide-Faced Spur Gears

1990 ◽  
Vol 112 (4) ◽  
pp. 590-595 ◽  
Author(s):  
J. H. Steward
Keyword(s):  
Experimental Data ◽  
Contact Line ◽  
Load Distribution ◽  
3D Model ◽  
Spur Gear ◽  
Point Load ◽  
Spur Gears ◽  
Line Load ◽  
Gear Teeth ◽  
Theoretical Results

In this paper, the requirements for an accurate 3D model of the tooth contact-line load distribution in real spur gears are summarized. The theoretical results (obtained by F.E.M.) for the point load compliance of wide-faced spur gear teeth are set out. These values compare well with experimental data obtained from tests on a large spur gear (18 mm module, 18 teeth).

Explanation of the Influence of Inflow Air Content on the Lift of Cavitating Hydrofoils

2018 ◽  
Vol 140 (8) ◽  
Author(s):  
Eduard Amromin
Keyword(s):  
Experimental Data ◽  
Theoretical Study ◽  
Lift Coefficient ◽  
Cavity Surface ◽  
Air Bubbles ◽  
Incoming Flow ◽  
Fluid Density ◽  
Air Content ◽  
Theoretical Results ◽  
Good Agreement

According to several known experiments, an increase of the incoming flow air content can increase the hydrofoil lift coefficient. The presented theoretical study shows that such increase is associated with the decrease of the fluid density at the cavity surface. This decrease is caused by entrainment of air bubbles to the cavity from the surrounding flow. The theoretical results based on such explanation are in a good agreement with the earlier published experimental data for NACA0015.

Sign in / Sign up

Export Citation Format

Share Document