We study some rare decays of $B$ mesons involving the quark-level transition $b\ensuremath{\rightarrow}q{l}^{+}{l}^{\ensuremath{-}}(q=d,s)$ in scalar leptoquark model. constrain parameter space using recently measured branching ratios ${B}_{s,d}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$ processes. Using such parameters, we obtain ratios, direct $CP$-violation and isospin asymmetries...

Recently, the $B$ factories BABAR and Belle as well LHCb experiment have reported several anomalies in semileptonic meson decays, such ${R}_{K}$ ${R}_{{D}^{(*)}}$ etc. We investigate these deviations by considering vector leptoquarks relevant for both $b\ensuremath{\rightarrow}s{l}^{+}{l}^{\ensuremath{-}}$ $b\ensuremath{\rightarrow}cl{\overline{\ensuremath{\nu}}}_{l}$ transitions. The leptoquark parameter space is constrained using experimentally measured branching ratios of...

Driven by the recent experimental hints of lepton-flavor-universality violation in bottom-quark sector, we consider a simple extension Standard Model (SM) with an additional vector leptoquark $V_{\rm LQ}({\bf 3},{\bf 1},2/3)$ and scalar diquark $S_{\rm DQ}({\bf 6},{\bf 1},4/3)$ under SM gauge group $SU(3)_c\times SU(2)_L\times U(1)_Y$, order to simultaneously explain $b \to s \ell^+ \ell^-$ (with $\ell=e,\mu$) c l^- \bar \nu_l$ $l=e,\mu,\tau$) flavor anomalies, as well generate small...

We study the effect of scalar leptoquarks in lepton flavor violating $B$ meson decays induced by flavor-changing transitions $b\ensuremath{\rightarrow}q{l}_{i}^{+}{l}_{j}^{\ensuremath{-}}$ with $q=s$, $d$. In standard model, these are extremely rare as they either two-loop suppressed or proceed via box diagrams tiny neutrino masses loop. However, leptoquark can occur at tree level and expected to have significantly large branching ratios. The parameter space is constrained using experimental...

In recent times, several hints of lepton nonuniversality have been observed in semileptonic $B$ meson decays, both the charged-current ($b\ensuremath{\rightarrow}cl{\overline{\ensuremath{\nu}}}_{l}$) and neutral-current ($b\ensuremath{\rightarrow}sll$) transitions. Motivated by these intriguing results, we perform a model-independent analysis ${\mathrm{\ensuremath{\Lambda}}}_{b}$ decays involving quark level transitions $b\ensuremath{\rightarrow}(u,c)l{\ensuremath{\nu}}_{l}$, order to...

We study the effect of scalar leptoquarks on exclusive rare $B$-meson decays ${\overline{B}}_{d}^{0}\ensuremath{\rightarrow}{\overline{K}}^{*0}(\ensuremath{\rightarrow}{K}^{\ensuremath{-}}{\ensuremath{\pi}}^{+}){l}^{+}{l}^{\ensuremath{-}}$ in full kinematically accessible physical region. work out constraints leptoquark parameter space using measured branching ratio ${B}_{s}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$ process by CMS and LHCb...

We investigate Majorana dark matter in a new variant of $U(1)_{L_{\mu}-L_{\tau}}$ gauge extension Standard Model, where the scalar sector is enriched with an inert doublet and $(\bar{3},1,1/3)$ leptoquark. compute WIMP-nucleon cross section leptoquark portal relic density mediated by components, $Z^{\prime}$ boson. constrain parameter space consistent Planck limit on density, PICO-60 LUX bounds spin-dependent direct detection section. Furthermore, we couplings from present experimental data...

We investigate the phenomenology of light GeV-scale fermionic dark matter in $U(1)_{L_\mu - L_{\tau}}$ gauge extension Standard Model. Heavy neutral fermions alongside with a $S_1(\overline{3}$,$1$,$1/3$) scalar leptoquark and an inert doublet are added to address flavor anomalies neutrino mass respectively. The boson associated $U(1)_{L_\mu-L_\tau}$ group mediates visible sector helps obtain correct relic density. Aided colored scalar, we constrain new model parameters by using branching...

Abstract This research aims to investigate the near-bed turbulent flow characteristics in a meandering channel with both mobile bed and immobile conditions. Experiments were performed prismatic rectangular non-uniform sand of size d50 = 0.523mm. The three-dimensional instantaneous fluid velocity was collected using Acoustic Doppler velocimeter which will provide important results related turbulence such as mean velocity, intensity, Reynolds shear stress, kinetic energy, skewness, kurtosis...

We investigate the consequence of vector leptoquarks on rare semileptonic lepton flavor violating decays $B$ meson which are more promising and effective channels to probe new physics signal. constrain resulting leptoquark parameter space by using branching ratios ${B}_{s,d}\ensuremath{\rightarrow}{l}^{+}{l}^{\ensuremath{-}}$, ${K}_{L}\ensuremath{\rightarrow}{l}^{+}{l}^{\ensuremath{-}}$ ${\ensuremath{\tau}}^{\ensuremath{-}}\ensuremath{\rightarrow}{l}^{\ensuremath{-}}\ensuremath{\gamma}$...

We study the scalar leptoquark effects on rare semileptonic decays of Λb baryon, governed by quark level transition . estimate branching ratios, forward–backward asymmetries, lepton polarisation parameters and flavour non-universality in these decay channels. find significant deviations from corresponding standard model predictions some observables due to effects. also investigate violating , ratios which are found be

We study the rare semileptonic decays of B mesons induced by as well transitions in scalar leptoquark (LQ) model, where LQs have representation (3, 2, 7/6) and 1/6) under standard model gauge group. The LQ parameter space is constrained using most recent experimental results on processes. Considering only baryon number conserving interactions, we estimate branching ratios for exclusive inclusive decay processes constraint parameters. also obtain low recoil (large lepton invariant mass, i.e.,...

Motivated by the recent measurement of lepton flavour nonuniversality ratio R K * LHCb Collaboration, we study implications vector leptoquarks on observed anomalies associated with B → l + -decay processes.The leptoquark couplings are constrained from measured branching ratios s -, L -and µ ∓ e ± processes.Using these couplings, estimate ratios, forward-backward and polarization asymmetries also form factor independent optimized observables (P ( ) i for - modes in high recoil limit.We other...

We study the effect of scalar leptoquark and $Z^\prime$ boson on rare decays $D$ mesons involving flavour changing transitions $c \to u l^+ l^- (l^\mp_i l^\pm_j)$. constrain new physics parameter space using branching ratio decay mode $D^0 \mu^+ \mu^-$ $D^0-\bar D^0$ oscillation data. compute ratios, forward-backward asymmetry parameters flat terms in $D^{+(0)} \pi^{+(0)} processes constrained parameters. The ratios lepton violating meson decays, such as \mu e, ~\tau e$ \mu^- e^+$ are also...

$B_q^0-B_^0 bar$ mixing offers a profound probe into the effects of new physics beyond Standard Model. In this paper, $B_s^0-B_s^0 and $B_d^0-B_d^0 mass differences are considered taking effect both Z-and Z' -mediated flavour-changing neutral currents in $B_q^0-B_q^0 (q = d, s). Our estimated boson is accessible at experiments LHC B-factories near future.

We investigate the effect of scalar leptoquarks and family non-universal $Z^\prime$ boson on rare leptonic decays $B_{s, d}^*$ mesons, mediated by FCNC transitions $b \to (d, s) l^+ l^-$. They are sensitive to a variety new physics operators as opposed $B_{s,d}$ modes hence, can provide an ideal testing ground look for beyond standard model. work out constraint parameter space using measured branching ratios $B_{d, s} \mu^+ \mu^-$ processes $B_q - \bar B_q$ mixing data. Using constrained...

We have investigated $B \to (K,K^*)(l\bar l,\nu\bar\nu)$ decay channels and predicted some form factor dependent observables (e.g. branching ratio, forward-backward asymmetry lepton polarization asymmetry) considering new physics contribution from non-universal $Z'$ model. found that there is appreciable difference between the standard model predictions. Recently, flavour non-universality parameters $R_K$ $R_{K^*}$ been measured by LHCb collaboration are to be different their These...

We study the effect of both Z and Z'-mediated flavor-changing neutral currents (FCNCs) on $ lambda_b arrow lambda l^+l^- (l = mu, tau) rare decay. find branching ratio is reasonably enhanced from its standard model value due to FCNCs, gives possibility new physics beyond model. The contribution Z'-boson depends upon precise mass Z' boson.

Very compelling deviations in the recently observed lepton nonuniversality observables $$ (R_{D^{(*)}}, R_{K^{(*)}}, R_{J/\psi } )$$ of semileptonic B meson decays from their Standard Model predictions hint towards presence some kind new physics beyond it. In this regard, we investigate effect $${\bar{B}}_{d(s)}^* \rightarrow P \ell {\bar{\nu }}_\ell decay processes, where $$P=D,\pi (D_s,K$$ ), a model independent way. We consider additional vector and scalar type interactions constrain...

${Z}^{\ensuremath{'}}$ bosons are known to naturally exist in well-motivated extensions of the standard model. The leptophobic gauge boson can appear models with ${E}_{6}$ symmetry due mixing gauge-boson kinetic terms. We show that flavor-changing neutral currents be generated some these ordinary ${d}_{R},$ ${s}_{R},$ and ${b}_{R}$ quark fields exotic ${h}_{R},$ where ${h}_{R}$ means an vector-singlet charge $\ensuremath{-}1/3$ $h.$ Since does not couple charged leptons, constraints on...

Semileptonic B meson decays induced by $b \to s(d) l^+ l^-$ flavour changing neutral current (FCNC) transitions are very important to probe the quark-flavour sector of standard model (SM) and also offer a test new physics (NP). Although there exists lot precise results on sl^+ processes, is lack sufficient data for dl^+ decays. Here, we interested study $B \pi \rho which proceed via transition at quark level. In this work, investigate differential branching ratio, forward-backward asymmetry,...

A phenomenological momentum dependent interaction (MDI) is considered to describe the equation of state (EOS) for isospin asymmetric nuclear matter (ANM), where density dependence symmetry basic input. In this interaction, energy shows soft density. Within nonrelativistic mean field approach we calculate fourth-order E sym, 4 (ρ). Our result that value (ρ) at normal ρ 0 ( = 0.161 fm -3 ) less than 1 MeV conforming empirical parabolic approximation EOS ANM . Then higher-order effects...