We present high quality long slit spectra along the major and minor axes out to 1.5-2 R_e [14-22 kpc] of four bright elliptical galaxies [NGC1600, NGC4125, NGC4636, NGC7619] obtained at the Hobby-Eberly Telescope (HET). We derive stellar kinematic profiles and Lick/IDS indices [Hβ,Mgb,Fe_{5015},Fe_{5270},Fe_{5335}, Fe_{5406}]. Moreover, for NGC4125 we derive gas kinematics and emission line strengths. We model the absorption line strengths using Simple Stellar Populations models that take into account the variation of and derive ages, total metallicity andα/Fe element abundances. Overall, we find that the three galaxies have old and α/Fe overabundant stellar populations with no significant gradients. The metallicity is supersolar at the center with a strong negative radial gradient. For NGC4125, several pieces of evidence point to a recent dissipational merger event. We calculate the broadband color profiles with the help of SSP models. All of the colors show sharp peaks at the center of the galaxies, mainly caused by the metallicity gradients, and agree well with the measured colors. Using the Schwarzschild's axisymmetric orbit superposition technique, we model the stellar kinematics to constrain the dark halos of the galaxies. We use the tight correlation between the Mgb strength and local escape velocity to set limits on the extent of the halos by testing different halo sizes. Logarithmic halos -- cut at 60~kpc -- minimize the overall scatter of the Mgb-V_esc relation. Larger cutoff radii are found if the dark matter density profile is decreasing more steeply at large radii. Using same method, we derived the local escape velocity V_esc profiles of 17 Coma galaxies. We further investigated the relation between the dark matter halo properties and the basic galaxies properties. The scales R_cut of DM are dependent on the luminosities and effective radius of the galaxies. The relation between the R_cut and luminosities and effective radius could be presented with a Faber-Jackson/Tully-Fisher like relation. The total DM mass and total mass of the galaxies are also dependent on the scales of the galaxies. The central dark matter fractions present no significant relations with the ages, α/Fe and total metallicities. And the results present that the brightest galaxies appear the most dark matter dominated. Furthermore, we investigated the dependence of DM sizes on the projected distance from the cluster center, unfortunately, no trend hints the DM sizes depending on the projected distance.
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