One-side Forward-backward Asymmetry in Top Quark Pair Production at CERN Large Hadron Collider

Both D0 and CDF at Tevatron reported the measurements of forward-backward asymmetry in top pair production, which showed possible deviation from the standard model QCD prediction. In this paper, we explore how to examine the {\em same} higher-order QCD effects at the more powerful Large Hadron Collider.Comment: 4 pages, 6 figures, Refs added, published versio

O(100GeV)\mathscr{O}(100 GeV) Deci-weak W′/Z′W^\prime/Z^\prime at Tevatron and LHC

Recently Tevatron released their measurements on invariant mass spectrum of electron/positron, as well as the di-jet arising from WW+WZ production with one W leptonically decay. Though the statistics is not significant, there are two bumps around 240 GeV and 120-160 GeV respectively. We proposed that the two bumps correspond to the extra light gauge bosons $Z^\prime$ and $W^\prime$, which couple with quarks with the deci-weak strength. In this brief report, we also simulated di-jet invariant mass distribution at the current running LHC.Comment: 8 pages, 3 EPS figures, ref added, figures update

Reimbursement and hospital competition in China

Quality and the costs of health care are of concern among patients. Differing from previous research into hospital competition, this article captures the impact of price subsidy of public hospitals on the quality of private hospitals, considering both horizontal and vertical product differentiation by employing a two-stage dynamic game under Cournot and Stackelberg competition. Firstly, the results of this study indicate that medical reimbursement of public hospitals has stimulating effects on the quality of private hospitals and the improvement of quality is related to the degree of hospital competition. Second, the quality of health care and patients’ surplus and social welfare are the highest under Stackelberg competition if the public hospital is the leader while the private hospital is the follower. Finally, the demand for health care rises with the price subsidy of public hospitals. These conclusions have significant policy implications for health care system reform, especially for China

New Color-Octet Vector Boson Revisit

Motivated by CDF recent measurements on di-jet invariant mass spectrum where di-jet is associated production with charged leptons ($e/\mu$) and missing energy, we re-examine the previous proposed massive color-octet axial-vector-like boson $Z_c$. Our simulation showed that the di-jet bump around 120-160 GeV can be induced by $Z_c$ with effective coupling $g_{Z_c q \bar q} =0.2 g_s$ (q represents the quark other than top and $g_s$ is the strong coupling constant). Moreover our numerical investigation indicated that the top quark forward-backward asymmetry $A_{FB}^t$ can be reproduced without distorting shape of differential cross section $d\sigma/d M_{t\bar t}$, provided that the $Z_c$ and top quark coupling is appropriately chosen ($g_{Z_c t \bar t} \simeq 4.5 g_{Z_c q \bar q}$). Our results also showed that the theoretical $A_{FB}^t$ as functions of $\Delta y$ and $M_{t\bar t}$ can be consistent with data within $1\sigma$ and $1.8\sigma$ respectively.Comment: 8 pages, 3 EPS figure

Harmonic and quasi-harmonic spheres, part III. Rectifiablity of the parabolic defect measure and generalized varifold flows

We study weakly convergent sequences of suitable weak solutions of heat flows of harmonic maps or approximated harmonic maps. We prove a dimensional stratification for the space-time concentration measure and verify that the concentration measure, viewed as a generalized varifold, moves according to the generalized varifold flow rule which reduces to the Brakke’s flow of varifold provided that the limiting harmonic map flow is suitable. We also establish an energy quantization for the density of the limiting varifold