Influence of C6_{6}H4_{4}(OH)2_{2} isomers on water disinfection by photocatalysis: a computational study

Solar disinfection by photocatalysis is one of the promising methods used for drinking water disinfection. It leads to the destruction of bacteria like $Escherichia$ $Coli$ ($E.$ $Coli$). In this paper, we compare our theoretical results with experimental ones done previously by A.G. Rinc\'on and his colleagues concerning the order of decay of C$_{6}$H$_{4}$(OH)$_{2}$ isomers in the presence of titanium dioxide TiO$_{2}$, and show the influence of optical properties of those molecules on $E.$ $Coli$ inactivation. According to the adsorption energy parameter, we find that catechol has the highest adsorption degree on titanium dioxide, followed by resorcinol, and finally hydroquinone. Three dihydroxybenzene isomers absorb photons belonging to ultraviolet (UV) range. The lowest absorption energies of resorcinol, catechol and hydroquinone are respectively 3.42, 4.44 and 4.49 eV.Comment: 7 pages, 3 figures, 1 tabl

Colored bosons on top FBA and angular cross section for ttˉt \bar t production

With full data set that corresponds to an integrated luminosity of 9.4 fb$^{-1}$, CDF has updated the top quark forward-backward asymmetry (FBA) as functions of rapidity difference $|\Delta y|$ and $t\bar t$ invariant mass $M_{t\bar t}$. Beside the sustained inconsistency between experiments and standard model (SM) predictions at large $|\Delta y|$ and $M_{t\bar t}$, an unexpected large first Legendre moment with $a_1= 0.39\pm 0.108$ is found. In order to solve the large top FBA, we study the contributions of color triplet scalar and color octet vector boson. We find that the top FBA at $|\Delta y| >1$ and $M_{t\bar t} > 450$ GeV in triplet and octet model could be enhanced to be around 30% and 20%, whereas the first Legendre moment is $a^{\bf Di}_1= 0.38$ and $a^{\bf Axi}_1= 0.23$, respectively.Comment: 13 pages, 5 figures; references adde

h \gamma \gamma Coupling in Higgs Triplet Model

We investigate Higgs boson decay into two photons in the type-II seesaw model. The rate of $h\to \gamma\gamma$ gets suppressed/enhanced in this model compared to the Standard Model (SM) due to the presence of the singly and doubly charged Higgs $H^\pm$ and $H^{\pm\pm}$.Comment: Latex, 7 pages, 2 Figures. The 2011 International Workshop on Future Linear Colliders (LCWS11), Granada, Spai

Two-Higgs-Doublet type-II and -III models and t→cht\to c h at the LHC

We study the constraints of the generic two-Higgs-doublet model (2HDM) type-III and the impacts of the new Yukawa couplings. For comparisons, we revisit the analysis in the 2HDM type-II. To understand the influence of all involving free parameters and to realize their correlations, we employ $\chi$-square fitting approach by including theoretical and experimental constraints, such as S, T, and U oblique parameters, the production of standard model Higgs and its decay to $\gamma\gamma$, $WW^*/ZZ^*$, $\tau^+\tau^-$, etc. The errors of analysis are taken at $68\%$, $95.5\%$, and $99.7\%$ confidence levels. Due to the new Yukawa couplings being associated with $\cos(\beta-\alpha)$ and $\sin(\beta -\alpha)$, we find that the allowed regions for $\sin\alpha$ and $\tan\beta$ in the type-III model can be broader when the dictated parameter $\chi_F$ is positive; however, for negative $\chi_F$, the limits are stricter than those in the type-II model. By using the constrained parameters, we find that the deviation from the SM in the $h\to Z\gamma$ can be of ${\cal O}(10\%)$. Additionally, we also study the top-quark flavor-changing processes induced at the tree level in the type-III model and find that when all current experimental data are considered, we get $Br(t\to c(h, H) )< 10^{-3}$ for $m_h=125.36$ and $m_H=150$ GeV and $Br(t\to cA)$ slightly exceeds $10^{-3}$ for $m_A =130$ GeV.Comment: 22 pages, 11 figures. v3: Slight change in the abstract, Figure.1 added and commented, the conclusion remains unchange

Third generation sfermions decays into Z and W gauge bosons: full one-loop analysis

The complete one-loop radiative corrections to third generation scalar fermions into gauge bosons Z and W^\pm is considered. We focus on \wt{f}_2 \to Z \wt{f}_1 and \wt{f}_i \to W^\pm \wt{f'}_j (f,f'=t,b). We include both SUSY-QCD, QED and full electroweak corrections. It is found that the electroweak corrections can be of the same order as the SUSY-QCD corrections. The two sets of corrections interfere destructively in some region of parameter space. The full one loop correction can reach 10% in some SUGRA scenario, while in model independent analysis like general MSSM, the one loop correction can reach 20% for large \tan\beta and large trilinear soft breaking terms A_b.Comment: Latex file, 18 pages, 8 figures, version to appear in PR

h\to \gamma \gamma In Inert Higgs Doublet Model

Motivated by the recent result reported from LHC on the di-photon search for a Standard Model (SM) Higgs-like boson. We discuss the implications of this possible signal in the framework of the Inert Higgs Doublet Model (IHDM), taking into account previous limits from Higgs searches at LEP, the Tevatron and the LHC as well as constraints from unitarity, vacuum stability and electroweak precision tests. We show that the charged Higgs contributions can interfere constructively or destructively with the W gauge bosons loops leading to enhancement or suppression of the di-photon rate with respect to SM rate. We show also that the invisible decay of the Higgs, if open, could affect the total width of the SM Higgs boson and therefore suppress the di-photon rate.Comment: 15 pages, added reference