Top and bottom squarks decays under cosmological bounds

Abstract

We investigate the fermionic decays of top squarkst 1,2 and bottom squarksb 1,2 in the Minimal Supersymmetric Standard Model with complex parameters M 1 , µ, A t and A b . In the analysis we particularly take into account the cosmological bounds imposed by WMAP data. We plot the CP phase dependences of stop and sbottom decay widths.

Squark decays in MSSM under the cosmological bounds

“…Here we simply choose mass values for the third family squarks as m t2 =m b2 =1000 GeV and m t1 =m b1 =750 GeV in order to compare the results with those of the first two families. We had taken more reasonable mass spectrum for squarks in our previous study [12]. The other masses are (m χ± 1 , m χ± 2 , m χ0 1 ) = ( 180GeV, 336 GeV, 150 GeV) for µ = 200 GeV and (m χ± 1 , m χ± 2 , m χ0 1 ) = (340 GeV, 680 GeV, 290 GeV) for µ = 350 GeV.…”

“…Here we simply choose mass values for the third family squarks as mt 2 = m˜b 2 = 1000 GeV and mt 1 = m˜b 1 = 750 GeV in order to compare the results with those of the first two families. We had taken more reasonable mass spectrum for squarks in our previous study [12]. The other masses are m χ± 1 , m χ± 2 , m χ0 For both sets of values by calculating the M Q and M Ũ values corresponding to mt 1 and mt 2 , we plot the decay widths for M Q M Ũ and M Q < M Ũ , separately.…”

“…The precision experiments by Wilkinson Microwave Anisotropy Probe (WMAP) [9] have put the following constraint on the relic density of cold dark matter 3 0.0945 < Ω CDM h 2 < 0.1287 (1.1) short study in this direction for the third family squarks [12] incorporating all the existing bounds on the SUSY parameter space by utilizing the study by Belanger et al [10] . This investigation showed us that the effects of M 1 and its phase ϕ U (1) on the decay widths of t 1,2 andb 1,2 are quite significant.…”

“…In this study, we present the numerical investigation of the fermionic two-body decays of squarks in MSSM with complex SUSY parameters. Actually, we had performed a short study in this direction for the third family squarks [12] incorporating all the existing bounds on the SUSY parameter space by utilizing the study by Bélanger et al [10]. This investigation showed us that the effects of M 1 and its phase ϕ U (1) on the decay widths of t1,2 and b1,2 are quite significant.…”

“…For both plots the other parameters are fixed to be tan β = 10, m H + = 1 TeV, A f = 1.2 TeV and ϕ µ = ϕ A f = 0. We here simply choose the generic masses for squarks as m q2 = 1000 GeV and m q1 = 750 GeV (q = u, d, c, s, t, b), although we had chosen more reasonable mass values in our previous note [12]. Taking different sets of values for squark masses around 1 TeV does not affect much neither the phase dependences nor the decay widths.…”