42
42

Sep 18, 2013
09/13

by
X. X. Chen

texts

######
eye 42

######
favorite 0

######
comment 0

In this paper, we study any K\"ahler manifold where the positive orthogonal bisectional curvature is preserved on the K\"ahler Ricci flow. Naturally, we always assume that the first Chern class $C_1$ is positive. In particular, we prove that any irreducible K\"ahler manifold with such property must be biholomorphic to $\mathbb{C}\mathbb{P}^n. $ This can be viewed as a generalization of Siu-Yau\cite{Siuy80}, Morri's solution \cite{Mori79} of the Frankel conjecture. According to...

Source: http://arxiv.org/abs/math/0606229v1

61
61

Sep 18, 2013
09/13

by
X. X. Chen

texts

######
eye 61

######
favorite 0

######
comment 0

In this paper, we first prove a folklore conjecture on a greatest lower bound of the Calabi energy in all K\"ahler manifold. Similar result in algebriac setting was obtained by S. K. Donaldson. Secondly, we give an upper/lower bound estimate of the K energy in terms of the geodesic distance and the Calabi energy. This is used to prove a theorem on convergence of K\"ahler metrics in holomorphic coordinates, with uniform bound on the Ricci curvature and the diameter. Thirdly, we set up...

Source: http://arxiv.org/abs/math/0606228v1

38
38

Sep 19, 2013
09/13

by
X. Chen; Z. Han

texts

######
eye 38

######
favorite 0

######
comment 0

Blue stragglers have been found in all populations. These objects are important in both stellar evolution and stellar population synthesis. Much evidence shows that blue stragglers are relevant to primordial binaries. Here, we summarize the links of binary evolution and blue stragglers, describe the characteristics of blue stragglers from different binary evolutionary channels, and show their consequences for binary population synthesis, such as for the integrated spectral energy distribution,...

Source: http://arxiv.org/abs/0910.2545v1

33
33

Sep 22, 2013
09/13

by
X. Chen; Z. Han

texts

######
eye 33

######
favorite 0

######
comment 0

We studied the effects of surface composition and thermohaline mixing caused by secular instability on the accreting components for low--mass binaries and applied the results on a short-orbital-period BS F190 in the old cluster M67. The results indicate no distinction in surface composition between the models with and without thermohaline mixing during Roche lobe overflow, but we still see the divergences of evolutionary tracks on HRD and CMD. The change of surface composition makes the gainer...

Source: http://arxiv.org/abs/astro-ph/0409607v1

36
36

Sep 18, 2013
09/13

by
F. K. Liu; X. Chen

texts

######
eye 36

######
favorite 0

######
comment 0

Supermassive black hole binary (SMBHB) is expected with the hierarchical galaxy formation model. Currently, physics processes dominating the evolution of a SMBHB are unclear. An interesting question is whether we could observationally determine the evolution of SMBHB and give constraints on the physical processes. Jet precession have been observed in many AGNs and generally attributed to disk precession. In this paper we calculate the time variation of jet precession and conclude that jet...

Source: http://arxiv.org/abs/0705.1077v1

186
186

Sep 17, 2013
09/13

by
X. X. Chen; G. Tian

texts

######
eye 186

######
favorite 0

######
comment 0

In our previous paper math.DG/0010008, we develop some new techniques in attacking the convergence problems for the K\"ahler Ricci flow. The one of main ideas is to find a set of new functionals on curvature tensors such that the Ricci flow is the gradient like flow of these functionals. We successfully find such functionals in case of Kaehler manifolds. On K\"ahler-Einstein manifold with positive scalar curvature, if the initial metric has positive bisectional curvature, we prove...

Source: http://arxiv.org/abs/math/0108179v2

48
48

Sep 22, 2013
09/13

by
Z. Wang; H. X. Chen

texts

######
eye 48

######
favorite 0

######
comment 0

Let U^>=0 denote the half quantum group for a fixed simple Lie algebra. We examine some properties and representation of U^>=0. We prove that the Hopf algebra U^>=0 is not quasi-cocommutative, and hence the category of left U^>=0-module is not a braided monoidal category. In the weight module category W, we describe all the simple objects and the projective objects. We also describe all simple Yetter-Drinfel'd U^>=0-weight modules.

Source: http://arxiv.org/abs/0908.0916v1

41
41

Sep 22, 2013
09/13

by
Z. Wang; H. X. Chen

texts

######
eye 41

######
favorite 0

######
comment 0

The representations of the pointed Hopf algebras $U$ and $\su$ are described, where $U$ and $\su$ can be regarded as deformations of the usual quantized enveloping algebras $U_q(\mathfrak{sl}(3))$ and the small quantum groups respectively. It is illustrated that these representations have a close connection with those of the quantized enveloping algebras $U_q(\mathfrak{sl}(2))$ and those of the half quantum groups of $\mathfrak{sl}(3)$.

Source: http://arxiv.org/abs/0908.0910v1

32
32

Sep 19, 2013
09/13

by
X. Chen; E. A. Spiegel

texts

######
eye 32

######
favorite 0

######
comment 0

Viscous resistance to changes in the volume of a gas arises when different degrees of freedom have different relaxation times. Collisions tend to oppose the resulting departures from equilibrium and, in so doing, generate entropy. Even for a classical gas of hard spheres, when the mean free paths or mean flight times of constituent particles are long, we find a nonvanishing bulk viscosity. Here we apply a method recently used to uncover this result for a classical rarefied gas to radiative...

Source: http://arxiv.org/abs/astro-ph/0102022v1

11
11

Jun 28, 2018
06/18

by
M. X. Chen; M. Weinert

texts

######
eye 11

######
favorite 0

######
comment 0

The Dirac electrons of graphene, an intrinsic zero gap semiconductor, uniquely carry spin and pseudospin that give rise to many fascinating electronic and transport properties. While isolated zigzag graphene nanoribbons are antiferromagnetic semiconductors, we show by means of first-principles and tight-binding calculations that zigzag graphene nanoribbons supported on graphene are half-metallic as a result of spin- and pseudospin-symmetry breaking. In particular, half-metallic Dirac cones are...

Topics: Mesoscale and Nanoscale Physics, Condensed Matter, Materials Science

Source: http://arxiv.org/abs/1509.04647

54
54

Sep 19, 2013
09/13

by
X. X. Chen; G. Tian

texts

######
eye 54

######
favorite 0

######
comment 0

The purpose of this paper is to establish a completely new partial regularity theory on certain homogeneous complex Monge-Ampere equations. Our partial regularity theory will be obtained by studying foliations by holomorphic curves and and their relations to homogeneous complex Monge-Ampere equations. As applications, we will prove the uniqueness of extremal K\"ahler metrics and give an necessary condition for existence of extremal K\"ahler metrics. Further applications will be...

Source: http://arxiv.org/abs/math/0507148v1

3
3.0

Jun 30, 2018
06/18

by
M. X. Chen; M. Weinert

texts

######
eye 3

######
favorite 0

######
comment 0

The band structure of the recently synthesized (3$\times$3) silicene monolayer on (4$\times$4) Ag(111) is investigated using density functional theory. A $k$-projection technique that includes the $k_\bot$-dependence of the surface bands is used to separate the contributions arising from the silicene and the substrate, allowing a consistent comparison between the calculations and the angle-resolved photoemission experiments. Our calculations not only reproduce the observed gap and linear...

Topics: Materials Science, Condensed Matter

Source: http://arxiv.org/abs/1408.3188

38
38

Sep 21, 2013
09/13

by
X. Chen; P. van Beek

texts

######
eye 38

######
favorite 0

######
comment 0

In recent years, many improvements to backtracking algorithms for solving constraint satisfaction problems have been proposed. The techniques for improving backtracking algorithms can be conveniently classified as look-ahead schemes and look-back schemes. Unfortunately, look-ahead and look-back schemes are not entirely orthogonal as it has been observed empirically that the enhancement of look-ahead techniques is sometimes counterproductive to the effects of look-back techniques. In this paper,...

Source: http://arxiv.org/abs/1106.0254v1

26
26

Sep 22, 2013
09/13

by
X. Chen; R. J. Gooding

texts

######
eye 26

######
favorite 0

######
comment 0

We have completed a numerical investigation of the Anderson-Hubbard model for three-dimensional simple cubic lattices using a real-space self-consistent Hartree-Fock decoupling approximation for the Hubbard interaction. In this formulation we treat the spatial disorder exactly, and therefore we account for effects arising from localization physics. We have examined the model for electronic densities well away 1/2 filling, thereby avoiding the physics of a Mott insulator. Several recent studies...

Source: http://arxiv.org/abs/0908.2139v1

66
66

Sep 17, 2013
09/13

by
E. Calabi; X. X. Chen

texts

######
eye 66

######
favorite 0

######
comment 0

This paper, the second of a series, deals with the function space of all smooth K\"ahler metrics in any given closed complex manifold $M$ in a fixed cohomology class. The previous result of the second author \cite{chen991} showed that the space is a path length space and it is geodesically convex in the sense that any two points are joined by a unique path, which is always length minimizing and of class C^{1,1}. This already confirms one of Donaldson's conjecture completely and verifies...

Source: http://arxiv.org/abs/math/0108162v1

85
85

Sep 23, 2013
09/13

by
M. X. Chen; R. Podloucky

texts

######
eye 85

######
favorite 0

######
comment 0

Reliable evaluation of phonon thermal conductivity is of importance for understanding mechanisms of phonon scatterings and therefore further benefits optimizing figure-of-merit of thermoelectric materials. Usually, when experimentally deriving the phonon mediated thermal conductivity $\kappa_{ph} = \kappa - \kappa_{el}$ from the measured total thermal conductivity $\kappa$ the constant Lorenz number L$_0$ is chosen for estimating $\kappa_{el}$ according to the Wiedemann-Franz law for simple...

Source: http://arxiv.org/abs/1212.0803v1

37
37

Sep 19, 2013
09/13

by
X. Zhang; X. Chen; Z. Han

texts

######
eye 37

######
favorite 0

######
comment 0

Masses are a fundamental parameter, but they are not well known for most hot subdwarfs. In general, the mass of a hot subdwarf is derived with asteroseismology or dynamical methods, for which it is often difficult to obtain the necessary data from observations. We intend to find an approach to deriving the masses of hot subdwarfs from observational data in the literature. We presented full evolutionary calculations for hot subdwarfs in a wide mass range (0.33 $M_\odot$ to 1.4 $M_\odot$) for a...

Source: http://arxiv.org/abs/0909.2560v1

41
41

Sep 23, 2013
09/13

by
X. Meng; X. Chen; Z. Han

texts

######
eye 41

######
favorite 0

######
comment 0

Following Paczy\'{n}ski & Zi\'{o}lkowski (1968) and Han et al. (1994), we assume that the envelope of an asymptotic giant branch (AGB) or a first giant branch (FGB) star is lost when the binding energy of the envelope is equal to zero ($\Delta W=0$) and the core mass of the AGB star or the FGB star at the point ($\Delta W=0$) is taken as the final mass. Using this assumption, we calculate the IFMRs for stars of different metallicities.We find that the IFMRs depends strongly on the...

Source: http://arxiv.org/abs/0710.2397v3

35
35

Sep 21, 2013
09/13

by
R. Bass; X. Chen; J. Rosen

texts

######
eye 35

######
favorite 0

######
comment 0

We study functionals of the form \[\zeta_{t}=\int_0^{t}...\int_0^{t} | X_1(s_1)+...+ X_p(s_p)|^{-\sigma}ds_1... ds_p\] where $X_1(t),..., X_p(t)$ are i.i.d. $d$-dimensional symmetric stable processes of index $0

Source: http://arxiv.org/abs/0712.2401v1

50
50

Sep 21, 2013
09/13

by
X-X. Chen; S. K. Donaldson

texts

######
eye 50

######
favorite 0

######
comment 0

This paper extends our earlier results to higher dimensions using a different approach, based on the rigidity of complex structures on certain domains.

Source: http://arxiv.org/abs/1104.4331v1

38
38

Sep 21, 2013
09/13

by
X-X. Chen; S. K. Donaldson

texts

######
eye 38

######
favorite 0

######
comment 0

We obtain an estimate for the volume of neighbourhoods of sets of large curvature in three-dimensional K\"ahler-Einstein manifolds.

Source: http://arxiv.org/abs/1104.0270v2

30
30

Sep 20, 2013
09/13

by
X. Meng; X. Chen; Z. Han

texts

######
eye 30

######
favorite 0

######
comment 0

The single-degenerate channel for the progenitors of type Ia supernovae (SNe Ia) are currently accepted, in which a carbon-oxygen white dwarf (CO WD) accretes hydrogen-rich material from its companion, increases its mass to the Chandrasekhar mass limit, and then explodes as a SN Ia. Incorporating the prescription of \citet{HAC99a} for the accretion efficiency into Eggleton's stellar evolution code and assuming that the prescription is valid for \emph{all} metallicities, we performed binary...

Source: http://arxiv.org/abs/0802.2471v2

42
42

Sep 21, 2013
09/13

by
X. Meng; X. Chen; Z. Han

texts

######
eye 42

######
favorite 0

######
comment 0

Using a simple analytic method, we calculate the impact effect between the ejecta of a SN Ia and its companion to survey the influence of initial parameters of the progenitor's system, which is useful for searching the companion in a explosion remnant. The companion models are obtained from Eggleton's evolution code.The results are divided into two groups based on mass transfer stage. For a given condition, more hydrogen-rich material is stripped from the envelope of a Hertzsprung-gap companion...

Source: http://arxiv.org/abs/0706.3581v1

39
39

Sep 20, 2013
09/13

by
J. Blanchet; X. Chen; H. Lam

texts

######
eye 39

######
favorite 0

######
comment 0

Let $Q_{\lambda}(t,y) $ be the number of people present at time $t$ with $y$ units of remaining service time in an infinite server system with arrival rate equal to $\lambda>0$. In the presence of a non-lattice renewal arrival process and assuming that the service times have a continuous distribution, we obtain a large deviations principle for $Q_{\lambda}(\cdot) /\lambda$ under the topology of uniform convergence on $[0,T]\times\lbrack0,\infty)$. We illustrate our results by obtaining the...

Source: http://arxiv.org/abs/1207.5164v1

3
3.0

Jun 30, 2018
06/18

by
D. Ding; X. Chen; A. J. Minnich

texts

######
eye 3

######
favorite 0

######
comment 0

Recently, a pump beam size dependence of thermal conductivity was observed in Si at cryogenic temperatures using time-domain thermal reflectance (TDTR). These observations were attributed to quasiballistic phonon transport, but the interpretation of the measurements has been semi-empirical. Here we present a numerical study of the heat conduction that occurs in the full 3D geometry of a TDTR experiment, including an interface, using the Boltzmann Transport Equation. We identify the radial...

Topics: Materials Science, Condensed Matter

Source: http://arxiv.org/abs/1402.1114

53
53

Sep 20, 2013
09/13

by
J. H. He; S. Takahashi; X. Chen

texts

######
eye 53

######
favorite 0

######
comment 0

A northern subsample of 89 Spitzer GLIMPSE extended green objects (EGOs), the candidate massive young stellar objects, are surveyed for molecular lines in two 1-GHz ranges: 251.5- 252.5 and 260.188-261.188 GHz. A comprehensive catalog of observed molecular line data and spectral plots are presented. Eight molecular species are undoubtedly detected: H13CO+, SiO, SO, CH3OH, CH3OCH3, CH3CH2CN, HCOOCH3, and HN13C. H13CO+ 3-2 line is detected in 70 EGOs among which 37 ones also show SiO 6-5 line,...

Source: http://arxiv.org/abs/1207.0306v1

7
7.0

Jun 28, 2018
06/18

by
M. X. Chen; Z. Zhong; M. Weinert

texts

######
eye 7

######
favorite 0

######
comment 0

We propose a guideline for exploring substrates that stabilize the monolayer honeycomb structure of silicene and germanene while simultaneously preserve the Dirac states: in addition to have a strong binding energy to the monolayer, a suitable substrate should be a large-gap semiconductor with a proper workfunction such that the Dirac point lies in the gap and far from the substrate states when their bands align. We illustrate our idea by performing first-principles calculations for silicene...

Topics: Condensed Matter, Materials Science

Source: http://arxiv.org/abs/1509.04641

53
53

Sep 20, 2013
09/13

by
X. X. Chen; G. Tian; Z. Zhang

texts

######
eye 53

######
favorite 0

######
comment 0

In this note, we define and study K\"ahler-Ricci flow with initial data not being smooth with some natural applications.

Source: http://arxiv.org/abs/0802.0809v1

35
35

Feb 3, 2016
02/16

by
F Wang; K Christiansen; J X Chen

texts

######
eye 35

######
favorite 0

######
comment 0

41
41

Sep 20, 2013
09/13

by
I. Rungger; X. Chen; U. Schwingenschlögl; S. Sanvito

texts

######
eye 41

######
favorite 0

######
comment 0

The effects of water wetting conditions on the transport properties of molecular nano-junctions are investigated theoretically by using a combination of classical molecular dynamics and first principles electronic transport calculations. These are at the level of the non-equilibrium Green's function method implemented for self-interaction corrected density functional theory. We find that water effectively produces electrostatic gating to the molecular junction, with a gating potential...

Source: http://arxiv.org/abs/1002.0226v1

48
48

Feb 3, 2016
02/16

by
Y T Ma; J X Chen; K Christiansen

texts

######
eye 48

######
favorite 0

######
comment 0

68
68

Sep 22, 2013
09/13

by
Song X. Chen; Liang Peng; Cindy L. Yu

texts

######
eye 68

######
favorite 0

######
comment 0

Markov processes are used in a wide range of disciplines, including finance. The transition densities of these processes are often unknown. However, the conditional characteristic functions are more likely to be available, especially for L\'{e}vy-driven processes. We propose an empirical likelihood approach, for both parameter estimation and model specification testing, based on the conditional characteristic function for processes with either continuous or discontinuous sample paths....

Source: http://arxiv.org/abs/1302.0122v1

38
38

Sep 21, 2013
09/13

by
X. Chen; P. W. Leung; R. J. Gooding

texts

######
eye 38

######
favorite 0

######
comment 0

We have obtained the exact ground state wave functions of the Anderson-Hubbard model for different electron fillings on a 4x4 lattice with periodic boundary conditions - for 1/2 filling such ground states have roughly 166 million states. When compared to the uncorrelated ground states (Hubbard interaction set to zero) we have found strong evidence of the very effective screening of the charge homogeneities due to the Hubbard interaction. We have successfully modelled these local charge...

Source: http://arxiv.org/abs/0709.4212v2

37
37

Sep 19, 2013
09/13

by
Z. Han; X. Chen; F. Zhang; Ph. Podsiadlowski

texts

######
eye 37

######
favorite 0

######
comment 0

Most stars are members of binaries, and the evolution of a star in a close binary system differs from that of an ioslated star due to the proximity of its companion star. The components in a binary system interact in many ways and binary evolution leads to the formation of many peculiar stars, including blue stragglers and hot subdwarfs. We will discuss binary evolution and the formation of blue stragglers and hot subdwarfs, and show that those hot objects are important in the study of...

Source: http://arxiv.org/abs/0910.2546v1

2
2.0

Jun 30, 2018
06/18

by
X. Chen; Y. -W. Lin; B. C. Odom

texts

######
eye 2

######
favorite 0

######
comment 0

The system of a trapped ion translationally excited by a blue-detuned near-resonant laser, sometimes described as an instance of a phonon laser, has recently received attention as interesting in its own right and for its application to non-destructive readout of internal states of non-fluorescing ions. Previous theoretical work has been limited to cases of two-level ions. Here, we perform simulations to study the dynamics of a phonon laser involving the $\Lambda$-type $^{138}\mbox{Ba}^{+}$ ion,...

Topics: Physics, Atomic Physics

Source: http://arxiv.org/abs/1409.5337

31
31

Sep 21, 2013
09/13

by
B. Wang; X. Meng; X. Chen; Z. Han

texts

######
eye 31

######
favorite 0

######
comment 0

Type Ia supernovae (SNe Ia) play an important role in astrophysics, especially in the study of cosmic evolution. There are several progenitor models for SNe Ia proposed in the past years. In this paper, we have carried out a detailed study of the He star donor channel, in which a carbon-oxygen white dwarf (CO WD) accretes material from a He main sequence star or a He subgiant to increase its mass to the Chandrasekhar mass. Employing Eggleton's stellar evolution code with an optically thick wind...

Source: http://arxiv.org/abs/0901.3496v1

2
2.0

Jun 30, 2018
06/18

by
Y. X. Chen; X. Y. Shen; J. P. Huang

texts

######
eye 2

######
favorite 0

######
comment 0

It is up to now a challenge to control the conduction of heat. Here we develop a method to distort the temperature distribution signature of an object at will. As a result, the object accurately exhibits the same temperature distribution signature as another object that is predetermined, but actually does not exist in the system. Our finite element simulations confirm the desired effect for different objects with various geometries and compositions. The underlying mechanism lies in the effects...

Topics: Materials Science, Condensed Matter

Source: http://arxiv.org/abs/1403.5894

2
2.0

Jun 29, 2018
06/18

by
X. Chen; V. Mishra; S. Maiti; P. J. Hirschfeld

texts

######
eye 2

######
favorite 0

######
comment 0

Several Fe chalcogenide superconductors without hole pockets at the Fermi level display high temperature superconductivity, in apparent contradiction to naive spin fluctuation pairing arguments. Recently, scanning tunneling microscopy measurements have measured the influence of impurities on some of these materials, and claimed that non-magnetic impurities do not create in-gap states, leading to the conclusion that the gap must be $s_{++}$, i.e. conventional $s$ wave with no gap sign change....

Topics: Superconductivity, Condensed Matter

Source: http://arxiv.org/abs/1606.00501

37
37

Sep 23, 2013
09/13

by
X. Chen; P. Madau; A. Sesana; F. K. Liu

texts

######
eye 37

######
favorite 0

######
comment 0

"Hard" massive black hole (MBH) binaries embedded in steep stellar cusps can shrink via three-body slingshot interactions. We show that this process will inevitably be accompanied by a burst of stellar tidal disruptions, at a rate that can be several orders of magnitude larger than that appropriate for a single MBH. Our numerical scattering experiments reveal that: 1) a significant fraction of stars initially bound to the primary hole are scattered into its tidal disruption loss cone...

Source: http://arxiv.org/abs/0904.4481v1

2
2.0

Jun 29, 2018
06/18

by
X. B. Ma; R. M. Qiu; Y. X. Chen

texts

######
eye 2

######
favorite 0

######
comment 0

Uncertainties of fission fraction is an important uncertainty source for the antineutrino flux prediction in a reactor antineutrino experiment. A new MC-based method of evaluating the covariance coefficients between isotopes was proposed. It was found that the covariance coefficients will varying with reactor burnup and which may change from positive to negative because of fissioning balance effect, for example, the covariance coefficient between $^{235}$U and $^{239}$Pu changes from 0.15 to...

Topics: Instrumentation and Detectors, Nuclear Experiment, Physics, High Energy Physics - Experiment

Source: http://arxiv.org/abs/1607.02894

47
47

Sep 22, 2013
09/13

by
A. Farhoodfar; X. Chen; R. J. Gooding; W. A. Atkinson

texts

######
eye 47

######
favorite 0

######
comment 0

Partially-projected Gutzwiller variational wavefunctions are used to describe the ground state of disordered interacting systems of fermions. We compare several different variational ground states with the exact ground state for disordered one-dimensional chains, with the goal of determining a minimal set of variational parameters required to accurately describe the spatially-inhomogeneous charge densities and spin correlations. We find that, for weak and intermediate disorder, it is sufficient...

Source: http://arxiv.org/abs/0906.3500v1

43
43

Sep 20, 2013
09/13

by
J. He; M. -X. Chen; X. -Q Chen; C. Franchini

texts

######
eye 43

######
favorite 0

######
comment 0

By means of hybrid density functional theory we investigate the evolution of the structural, electronic and magnetic properties of the colossal magnetoresistance (CMR) parent compound LaMnO$_3$ under pressure. We predict a transition from a low pressure antiferromagnetic (AFM) insulator to a high pressure ferromagnetic (FM) transport half-metal (tHM), characterized by a large spin polarization (~ 80-90 %). The FM-tHM transition is associated with a progressive quenching of the cooperative...

Source: http://arxiv.org/abs/1205.1303v1

31
31

Jul 20, 2013
07/13

by
H. Y. Geng; M. H. F. Sluiter; N. X. Chen

texts

######
eye 31

######
favorite 0

######
comment 0

A model is constructed in which pair potentials are combined with the cluster expansion method in order to better describe the energetics of structurally relaxed substitutional alloys. The effect of structural relaxations away from the ideal crystal positions, and the effect of ordering is described by interatomic-distance dependent pair potentials, while more subtle configurational aspects associated with correlations of three- and more sites are described purely within the cluster expansion...

Source: http://arxiv.org/abs/1203.0626v1

2
2.0

Jun 28, 2018
06/18

by
H. -X. Chen; L. Maiani; A. D. Polosa; V. Riquer

texts

######
eye 2

######
favorite 0

######
comment 0

The observed Y(4260)\to \gamma + X(3872) decay is a natural consequence of the diquark-antidiquark description of Y and X resonances. In this note we attempt an estimate of the transition rate, \Gamma_{\rm rad}, by a non-relativistic calculation of the electric dipole term of a diquarkonium bound state. We compute \Gamma_{\rm rad} for generic composition values of the isospin of X and Y. Specializing to I=0 for X(3872), we find \Gamma_{\rm rad}= 496~keV for Y(4260) with I=0 and \Gamma_{\rm...

Topic: High Energy Physics - Phenomenology

Source: http://arxiv.org/abs/1510.03626

36
36

Sep 23, 2013
09/13

by
F. Fazileh; X. Chen; R. J. Gooding; K. V. Tabunshchyk

texts

######
eye 36

######
favorite 0

######
comment 0

We have examined the behaviour of noninteracting electrons moving on a corner-sharing tetrahedral lattice into which we introduce a uniform (box) distribution, of width W, of random on-site energies. We have used both the relative localization length and the spectral rigidity to analyze the nature of the eigenstates, and have determined both the mobility edge trajectories as a function of W, and the critical disorder, Wc, beyond which all states are localized. We find (i) that the mobility edge...

Source: http://arxiv.org/abs/cond-mat/0511659v4

2
2.0

Jun 29, 2018
06/18

by
H. Xiong; X. Chen; P. Podsiadlowski; Y. Li; Z. Han

texts

######
eye 2

######
favorite 0

######
comment 0

From the canonical binary scenario, the majority of sdBs are produced from low-mass stars with degenerate cores where helium is ignited in a way of flashes. Due to numerical difficulties, the models of produced sdBs are generally constructed from more massive stars with non-degenerate cores, leaving several uncertainties on the exact characteristics of sdB stars. Employing MESA, we systematically studied the characteristics of sdBs produced from the common envelope (CE) ejection channel, and...

Topics: Astrophysics, Solar and Stellar Astrophysics

Source: http://arxiv.org/abs/1608.08739

53
53

Sep 17, 2013
09/13

by
J. G. Muga; X. Chen; Ibáñez; I. Lizuain; A. Ruschhaupt

texts

######
eye 53

######
favorite 0

######
comment 0

Two methods to change a quantum harmonic oscillator frequency without transitions in a finite time are described and compared. The first method, a transitionless-tracking algorithm, makes use of a generalized harmonic oscillator and a non-local potential. The second method, based on engineering an invariant of motion, only modifies the harmonic frequency in time, keeping the potential local at all times.

Source: http://arxiv.org/abs/0912.4178v1

4
4.0

Jun 30, 2018
06/18

by
X. Chen; T. Gehrmann; E. W. N. Glover; M. Jaquier

texts

######
eye 4

######
favorite 0

######
comment 0

We compute the cross section and differential distributions for the production of a Standard Model Higgs boson in association with a hadronic jet to next-to-next-to-leading order in quantum chromodynamics (QCD). In Higgs boson studies at the LHC, final states containing one jet are a dominant contribution to the total event rate, and their understanding is crucial for improved determinations of the Higgs boson properties. We observe substantial higher order corrections to transverse momentum...

Topics: High Energy Physics - Phenomenology, High Energy Physics - Experiment

Source: http://arxiv.org/abs/1408.5325

2
2.0

Jun 29, 2018
06/18

by
Lorin Crawford; Anthea Monod; Andrew X. Chen; Sayan Mukherjee; Raúl Rabadán

texts

######
eye 2

######
favorite 0

######
comment 0

In this paper we propose a novel statistic, the smooth Euler characteristic transform (SECT). The SECT is designed to integrate shape information into standard statistical models. More specifically, the SECT allows us to represent shapes as a collection of vectors with little to no loss in information. As a result, detailed shape information can be combined with biomarkers such as gene expression in standard statistical frameworks, such as linear mixed models. We illustrate the utility of the...

Topics: Applications, Statistics

Source: http://arxiv.org/abs/1611.06818

32
32

Sep 23, 2013
09/13

by
X. Chen; I. Rungger; C. D. Pemmaraju; U. Schwingenschlogl; S. Sanvito

texts

######
eye 32

######
favorite 0

######
comment 0

Rapid and cost-effective DNA sequencing at the single nucleotide level might be achieved by measuring a transverse electronic current as single-stranded DNA is pulled through a nano-sized pore. In order to enhance the electronic coupling between the nucleotides and the electrodes and hence the current signals, we employ a pair of single-walled close-ended (6,6) carbon nanotubes (CNTs) as electrodes. We then investigate the electron transport properties of nucleotides sandwiched between such...

Source: http://arxiv.org/abs/1109.1531v1