Reaching the minimum ideal in a finite semigroup

We introduce the depth parameters of a finite semigroup, which measure how hard it is to produce an element in the minimum ideal when we consider generating sets satisfying some minimality conditions. We estimate such parameters for some families of finite semigroups, and we obtain an upper bound for wreath products and direct products of two finite (transformation) monoids. Keywords: semigroup, generating set, minimum ideal, A-depth of a semigroupComment: 29 page

Energy dependence of elliptic flow of ϕ\phi-meson in STAR at RHIC

We present the measurement of elliptic flow ($v_{2}$) as a function of transverse momentum ($p_{T}$) for the $\phi$-meson in Au+Au collisions at $\sqrt{s_{NN}}$ = 7.7, 11.5 and 39 GeV. At low $p_{T}$ $\phi$-meson $v_{2}$ decreases with decrease in beam energy. The number of constituent quark ($n_{\rm{cq}}$) scaled $v_{2}$ for $\phi$-meson vs ($m_{T} - m_{0}$)/$n_{\rm{cq}}$ follows similar trend as other hadrons for $\sqrt{s_{NN}}$= 39 GeV whereas the $n_{\rm{cq}}$ scaled $v_{2}$ for $\phi$-mesons follows a different trend compared to the other hadrons at $\sqrt{s_{NN}}$= 11.5 GeV.Comment: Conference proceedings for Strangeness in Quark Matter 2011, Cracow, Poland, September 18-24, 201