We study the scattering of light pseudoscalar mesons (π, K) off charmed mesons (D,

We present a spectrum of highly excited charmonium mesons up to around 4.5 GeV calculated using dynamical lattice QCD. Employing novel computational techniques and the variational method with a large basis of carefully constructed operators, we extract and reliably identify the continuum spin of an extensive set of excited states, states with exotic quantum numbers (0+-, 1-+, 2+-) and states with high spin. Calculations are performed on two lattice volumes with pion mass approximately 400 MeV and the mass determinations have high statistical precision even for excited states. We discuss the results in light of experimental observations, identify the lightest 'supermultiplet' of hybrid mesons and comment on the phenomenological implications of the spectrum of exotic mesons.Comment: 33 pages, 17 figures; v2: minor changes to reflect published versio

[1] This paper presents a statistical study of the pre-earthquake ionospheric anomaly by using the total electron content (TEC) data from the global ionosphere map. A total of 736 M ≥ 6.0 earthquakes in the global area during 2002-2010 are selected. The anomaly day is first defined. Then the occurrence rates of abnormal days for both the days within 1-21 days prior to the earthquakes (P E ) and the background days (P N ) are calculated. The results show that the values of P E depend on the earthquake magnitude, the earthquake source depth, and the number of days prior to the earthquake. The P E is larger for earthquakes with greater magnitude and lower depth and for days closer to the earthquakes. The results also show that the occurrence rate of anomaly within several days before the earthquakes is overall larger than that during the background days, especially for the large-magnitude and low-depth earthquakes. These results indicate that the anomalous behavior of TEC within just a few days before the earthquakes is related with the forthcoming earthquakes with high probability.

We compute the masses of the singly and doubly charmed baryons in full QCD using the relativistic Fermilab action for the charm quark. For the light quarks we use domain-wall fermions in the valence sector and improved Kogut-Susskind sea quarks. We use the lowlying charmonium spectrum to tune our heavy-quark action and as a guide to understanding the discretization errors associated with the heavy quark. Our results are in good agreement with experiment within our systematics. For the Ξ cc , we find the isospin-averaged mass to be M Ξcc = 3665 ± 17 ± 14 +0 −78 MeV; the three given uncertainties are statistical, systematic and an estimate of lattice discretization errors, respectively. In addition, we predict the mass splitting of the (isospin-averaged) spin-1/2 Ω cc with the Ξ cc to be M Ωcc − M Ξcc = 98 ± 9 ± 22 ± 13 MeV (in this mass splitting, the leading discretization errors are also suppressed by SU (3) symmetry). Combining this splitting with our determination of M Ξcc leads to our prediction of the spin-1/2 Ω cc mass, M Ωcc = 3763 ± 19 ± 26 +13 −79 MeV.

Lepton scattering is an established ideal tool for studying inner structure of small particles such as nucleons as well as nuclei. As a future high energy nuclear physics project, an Electron-ion collider in China (EicC) has been proposed. It will be constructed based on an upgraded heavy-ion accelerator, High Intensity heavy-ion Accelerator Facility (HIAF) which is currently under construction, together with a new electron ring. The proposed collider will provide highly polarized electrons (with a polarization of ∼80%) and protons (with a polarization of ∼70%) with variable center of mass energies from 15 to 20 GeV and the luminosity of (2–3) × 1033 cm−2 · s−1. Polarized deuterons and Helium-3, as well as unpolarized ion beams from Carbon to Uranium, will be also available at the EicC.The main foci of the EicC will be precision measurements of the structure of the nucleon in the sea quark region, including 3D tomography of nucleon; the partonic structure of nuclei and the parton interaction with the nuclear environment; the exotic states, especially those with heavy flavor quark contents. In addition, issues fundamental to understanding the origin of mass could be addressed by measurements of heavy quarkonia near-threshold production at the EicC. In order to achieve the above-mentioned physics goals, a hermetical detector system will be constructed with cutting-edge technologies.This document is the result of collective contributions and valuable inputs from experts across the globe. The EicC physics program complements the ongoing scientific programs at the Jefferson Laboratory and the future EIC project in the United States. The success of this project will also advance both nuclear and particle physics as well as accelerator and detector technology in China.

We study the scattering of light pseudoscalar mesons (π, K) off charmed mesons (D, D s ) in full lattice QCD. The S-wave scattering lengths are calculated using Lüscher's finite volume technique. We use a relativistic formulation for the charm quark. For the light quark, we use domain-wall fermions in the valence sector and improved Kogut-Susskind sea quarks. We calculate the scattering lengths of isospin-3/2 Dπ, D s π, D s K, isospin-0 DK and isospin-1 DK channels on the lattice. For the chiral extrapolation, we use a chiral unitary approach to next-to-leading order, which at the same time allows us to give predictions for other channels. It turns out that our results support the interpretation of the D * s0 (2317) as a DK molecule. At the same time, we also update a prediction for the isospin breaking hadronic decay width Γ(D *

Abstract.In the present work we use the NASA-JPL global ionospheric maps of total electron content (TEC), firstly to construct TEC maps (TEC vs. magnetic local time MLT, and magnetic latitude MLAT) in the interval from 1999 to 2005. These TEC maps were, in turn, used to estimate the annualto-mean amplitude ratio, A 1 , and the semiannual-to-mean amplitude ratio, A 2 , as well as the latitudinal symmetrical and asymmetrical parts, A and A of A 1 . Thus, we investigated in detail the TEC climatology from maps of these indices, with an emphasis on the quantitative presentation for local time and latitudinal changes in the seasonal, annual and semiannual anomalies of the ionospheric TEC. Then we took the TEC value at 14:00 LT to examine various anomalies at a global scale following the same procedure. Results reveal similar features appearing in NmF2, such as that the seasonal anomaly is more significant in the near-pole regions than in the far-pole regions and the reverse is true for the semiannual anomaly; the winter anomaly has least a chance to be observed at the South America and South Pacific areas. The most impressive feature is that the equinoctial asymmetry is most prominent at the East Asian and South Australian areas. Through the analysis of the TIMED GUVI columnar [O/N2] data, we have investigated to what extent the seasonal, annual and semiannual variations can be explained by their counterparts in [O/N2]. Results revealed that the [O/N2] variation is a major contributor to the daytime winter anomaly of TEC, and it also contributes to some of the semiannual and annual anomalies. The contribution to the anomalies unexplained by the [O/N2] data could possibly be due to the dynamics associated with thermospheric winds and electric fields.

We study the scattering of the light-flavor pseudoscalar mesons (π, K, η) off the groundstate charmed mesons (D, D s ) within chiral effective field theory. The recent lattice simulation results on various scattering lengths and the finite-volume spectra both in the moving and center-of-mass frames, most of which are obtained at unphysical meson masses, are used to constrain the free parameters in our theory. Explicit formulas to include the S-and P -wave mixing to determine the finite-volume energy levels are provided. After a successful reproduction of the lattice data, we perform a chiral extrapolation to predict the quantities with physical meson masses, including phase shifts, inelasticities, resonance pole positions and the corresponding residues from the scattering of the light pseudoscalar and charmed mesons. Chiral effective field theory provides a useful theoretical framework to perform such studies. Many works along this research line have been done by several different groups in the last decade [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24]. In order to constrain the unknown parameters, one usually needs scattering information as input. However, experimental observables from the scattering of the light pseudoscalar and ground-state charmed mesons, such as phase shifts and inelasticities, are still not available nowadays.Fortunately, lattice QCD provides an alternative way to obtain such kinds of data [24][25][26][27][28][29]. In Ref. [24], the scattering lengths of five scattering channels: isospin-3/2 Dπ, D s π, D s K, isospin-0 DK and isospin-1 DK, are calculated at four different values of unphysical pion (quark) masses. The DK scattering amplitude is obtained indirectly from unitarized chiral perturbation theory (ChPT) with the relevant low-energy constants (LECs) determined from the aforementioned five channels. The direct lattice calculation of DK scattering is performed in Refs. [25][26][27] and the I = 1/2 Dπ scattering length is calculated in lattice QCD in Ref. [29]. In these works, the effects of the coupled channels are ignored. Recently, a sophisticated lattice calculation of the coupled-channel scattering of Dπ, Dη and D sK was presented in Ref. [28], in which a large amount of energy levels in the finite volume are obtained by using many interpolating operators and various moving frames. These lattice data have been extensively used in ChPT studies to constrain the chiral amplitudes [13-16, 19, 20, 22, 24]. However, all of these studies used only a small part of the available lattice data up to now. A more complete data set is expected to be able to determine the chiral amplitudes more precisely. In this work, we perform an extensive study of the light pseudoscalar mesons scattering off the ground-state charmed mesons in unitarized ChPT. All of the 2+1 flavor lattice results, including the finite-volume energy levels and the scattering lengths obtained in Ref. [24][25][26]28], are used to determine the parameters in the unitarized ChPT. Note that the 2-flav...