Asymptotic regimes for the occupancy scheme of multiplicative cascades

In the classical occupancy scheme, one considers a fixed discrete probability measure ${\bf p}=(p_i: {i\in{\cal I}})$ and throws balls independently at random in boxes labeled by ${\cal I}$, such that $p_i$ is the probability that a given ball falls into the box $i$. In this work, we are interested in asymptotic regimes of this scheme in the situation induced by a refining sequence $({\bf p}(k) : k\in\N)$ of random probability measures which arise from some multiplicative cascade. Our motivation comes from the study of the asymptotic behavior of certain fragmentation chain

Effects of Extra Dimensions on Unitarity and Higgs Boson Mass

We study the unitarity constraint on the two body Higgs boson elastic scattering in the presence of extra dimensions. The contributions from exchange of spin-2 and spin-0 Kaluza-Klein states can have large effect on the partial wave amplitude. Unitarity condition restrict the maximal allowed value for the ratio $r$ of the center of mass energy to the gravity scale to be less than one. Although the constraint on the standard Higgs boson mass for $r$ of order one is considerably relaxed, for small $r$ the constraint is similar to that in the Standard Model. The resulting bound on the Higgs boson mass is not dramatically altered if perturbative calculations are required to be valid up to the maximal allowed value for $r$.Comment: References added, RevTex, 9 pages with two figure

Extra Dimensions and Higgs Pair Production at Photon Colliders

We show that new physics effects due to extra dimensions can dramatically affect Higgs pair production at photon colliders. We find that the cross section due to extra dimensions with the scale $M_S$ of new physics around 1.5 TeV, the cross section can be as large as 0.11 pb (1.5pb) for monochromatic photon collision, $\gamma \gamma \to HH$, with the collider energy $\sqrt{s} = 0.5 (1)$ TeV for Higgs mass of 100 (350) GeV. The cross section can be 3 fb (2.7 fb) for the same parameters for collisions using photon beams from electron or positron back scattered by laser. These cross sections are much larger than those predicted in the Standard Model. Higgs pair production at photon colliders can provide useful tests for new physics due to extra dimensions.Comment: Typos corrected and updated references, Rev-Tex, 11 pages with one figur

Higgs boson enhancement effects on squark-pair production at the LHC

We study the Higgs boson effects on third-generation squark-pair production in proton-proton collision at the CERN Large Hadron Collider (LHC), including \Stop \Stop^*, \Stop\Sbot^*, and \Sbot \Sbot^*. We found that substantial enhancement can be obtained through s-channel exchanges of Higgs bosons at large $\tan\beta$, at which the enhancement mainly comes from $b\bar b$, $b\bar c$, and $c\bar b$ initial states. We compute the complete set of electroweak (EW) contributions to all production channels. This completes previous computations in the literature. We found that the EW contributions can be significant and can reach up to 25% in more general scenarios and at the resonance of the heavy Higgs boson. The size of Higgs enhancement is comparable or even higher than the PDF uncertainties and so must be included in any reliable analysis. A full analytical computation of all the EW contributions is presented.Comment: 23 pages, 7 figures, 1 tabl

Associated production of neutral toppion with a pair of heavy quarks in γγ\gamma\gamma collisions

We have studied a neutral toppion production process $\gamma\gamma\to f\bar{f}\Pi_{t}^{0}(f=t,b)$ in the topcolor-assisted technicolor(TC2) model. We find that the cross section of $\gamma\gamma\to t\bar{t}\Pi_{t}^{0}$ is much larger than that of $\gamma\gamma\to b\bar{b}\Pi_{t}^{0}$. On the other hand, the cross section can be obviously enhanced with the increasing of c.m.energy. With $\sqrt{s}=1600$ GeV, the cross section of $t\bar{t}\Pi_t^0$ production can reach the level of a few fb. The results show that $\gamma\gamma\to t\bar{t}\Pi^0_t \to t\bar{t}(t\bar{c})$ is the most ideal channel to detect neutral toppion due to the clean SM background. With such sufficient signals and clean background, neutral toppion could be detected at TESLA with high c.m.energy.Comment: 11 pages, 5 figure

Accuracy of breeding values of 'unrelated' individuals predicted by dense SNP genotyping

<p>Abstract</p> <p>Background</p> <p>Recent developments in SNP discovery and high throughput genotyping technology have made the use of high-density SNP markers to predict breeding values feasible. This involves estimation of the SNP effects in a training data set, and use of these estimates to evaluate the breeding values of other 'evaluation' individuals. Simulation studies have shown that these predictions of breeding values can be accurate, when training and evaluation individuals are (closely) related. However, many general applications of genomic selection require the prediction of breeding values of 'unrelated' individuals, i.e. individuals from the same population, but not particularly closely related to the training individuals.</p> <p>Methods</p> <p>Accuracy of selection was investigated by computer simulation of small populations. Using scaling arguments, the results were extended to different populations, training data sets and genome sizes, and different trait heritabilities.</p> <p>Results</p> <p>Prediction of breeding values of unrelated individuals required a substantially higher marker density and number of training records than when prediction individuals were offspring of training individuals. However, when the number of records was 2*N_e*L and the number of markers was 10*N_e*L, the breeding values of unrelated individuals could be predicted with accuracies of 0.88 – 0.93, where N_eis the effective population size and L the genome size in Morgan. Reducing this requirement to 1*N_e*L individuals, reduced prediction accuracies to 0.73–0.83.</p> <p>Conclusion</p> <p>For livestock populations, 1N_eL requires about ~30,000 training records, but this may be reduced if training and evaluation animals are related. A prediction equation is presented, that predicts accuracy when training and evaluation individuals are related. For humans, 1N_eL requires ~350,000 individuals, which means that human disease risk prediction is possible only for diseases that are determined by a limited number of genes. Otherwise, genotyping and phenotypic recording need to become very common in the future.</p

Modern microwave methods in solid state inorganic materials chemistry: from fundamentals to manufacturing

No abstract available

Study of qqqccˉqqqc\bar{c} five quark system with three kinds of quark-quark hyperfine interaction

The low-lying energy spectra of five quark systems $uudc\bar{c}$ (I=1/2, S=0) and $udsc\bar{c}$ (I=0, S=-1) are investigated with three kinds of schematic interactions: the chromomagnetic interaction, the flavor-spin dependent interaction and the instanton-induced interaction. In all the three models, the lowest five quark state ($uudc\bar{c}$ or $udsc\bar{c}$) has an orbital angular momentum L=0 and the spin-parity $J^{P}=1/2^{-}$; the mass of the lowest $udsc\bar{c}$ state is heavier than the lowest $uudc\bar{c}$ state