相关论文: The ALLM parameterization of sigma_{tot}(gamma* p)…

Various parametrizations of sigma(gamma p) are tried out on the small-x fixed target and HERA data. A two-Pomeron type parametrization is found to give the best reproduction of the data. The data indicate that the value of lambda(eff) for…

We perform a detailed analysis on the scaling properties of the total $\gamma^*\mathrm{p}$ cross section, $\sigma_{\gamma^*\mathrm{p}}$. We write the cross section as a product of two functions $W$ and $V$ representing, respectively, the…

Determinations of alpha_s are reviewed. Current results are limited to a precision of around 3-20%, largely by theoretical uncertainties. All measurements are consistent with a `world average' value of 0.118 +- 0.005 and there is no…

A parametrisation of the real photon structure function F_2^gamma in the low Q^2, low x region is formulated. It includes both the VMD and the QCD components, the latter suitably extrapolated to the low Q^2 region and based on arbitrary…

The parametrisation of the photon structure function in the low Q^2 region is formulated. It includes the VMD contribution and the QCD improved parton model component suitably extrapolated to the low Q^2 region. The parametrisation…

The data available from the A2 Collaboration at MAMI were analyzed to select the $\gamma p\to \pi^0\eta p$ reaction on an event-by-event basis, which allows for partial-wave analyses of three-body final states to obtain more reliable…

We present the details of a global $\chi^2$ analysis of electroweak data, including fermion masses and mixing angles, in SO(10) SUSY GUTs. Just as precision electroweak data is used to test the Standard Model, the well determined Standard…

We give a characterization of $L^{p}(\sigma)$ for uniformly rectifiable measures $\sigma$ using Tolsa's $\alpha$-numbers, by showing, for $1<p<\infty$ and $f\in L^{p}(\sigma)$, that \[ \lVert f\rVert_{L^{p}(\sigma)}\sim…

We show that the experimental data for the total virtual-photon proton cross section, \sigma_{\gamma^*p} (W^2, Q^2), for x_{bj} \lsim 0.1 lie on a universal curve, when plotted against \eta = (Q^2 + m^2_0)/ \Lambda^2(W^2), where \Lambda^2…

We discuss the reaction $\pi^- e^- \to \pi^- e^- \pi^{0}$ with the purpose of obtaining information on the $\gamma \pi \to \pi\pi$ anomalous amplitude ${\cal F}_{3\pi}$. We compare a full calculation at ${\cal O}(p^6)$ in chiral…

I investigate the use of Pearson's chi-square statistic, the Maximum Likelihood Ratio statistic for Poisson distributions, and the chi-square-gamma statistic (Mighell 1999, ApJ, 518, 380) for the determination of the goodness-of-fit between…

We propose a class of weighted $L_2$-type tests of fit to the Gamma distribution. Our novel procedure is based on a fixed point property of a new transformation connected to a Steinian characterization of the family of Gamma distributions.…

New measurements are presented of the photon structure function F_2^gamma(Q) at four values of Q^2 between 9 and 59 GeV/c^2 based on data collected with the OPAL detector at centre-of-mass energies of 161-172 GeV, with a total integrated…

Assuming that the actual values of $m_t$ and the data set ($\Gamma_b$, $\Gamma_h$, $\Gamma_Z$, $R_b$, $R_c$, $R_l$) are within their $1-\sigma$ errors as reported by CDF, D0 and by LEP Collaborations, the parameter $\Delta^{new}_b$ which…

A new sum rule determines the nucleon sigma term by the \pi N elastic scattering threshold parameters alone. This "threshold" value of \sigma(2\mu^2) provides an independent check of existing values obtained from global dispersive analyses,…

Verification of theoretical predictions of an oscillating behavior of the fine-structure constant, alpha, with cosmic time requires high precision measurements at individual redshifts, while in earlier studies the mean Delta alpha/alpha…

With use of a new $ C+N $ amplitude which correctly accounts for CNI to all orders in $\alpha$ the values of the parameters $\rho^{pp},\sigma_{\mbox{tot}}^{pp}$ and $B^{pp}$ are analysed on the basis of data published by the TOTEM and ATLAS…

A fit to world data on the photon-proton cross section sigma L+T and the unpolarised structure function F2 is presented. The 23-parameter ALLM model based on Reggeon and Pomeron exchange is used. Cross section data were reconstructed to…

A general purpose fitting model for one-dimensional astrometric signals is developed, building on a maximum likelihood framework, and its performance is evaluated by simulation over a set of realistic image instances. The fit quality is…

We use a configuration space chiral model in order to evaluate nucleon and delta sigma-terms. Analytic expressions are consistent with chiral counting rules and give rise to expected non-analytic terms in the chiral limit. We obtain the…