77,912 research outputs found

    An Efficient Vein Pattern-based Recognition System

    Full text link
    This paper presents an efficient human recognition system based on vein pattern from the palma dorsa. A new absorption based technique has been proposed to collect good quality images with the help of a low cost camera and light source. The system automatically detects the region of interest from the image and does the necessary preprocessing to extract features. A Euclidean Distance based matching technique has been used for making the decision. It has been tested on a data set of 1750 image samples collected from 341 individuals. The accuracy of the verification system is found to be 99.26% with false rejection rate (FRR) of 0.03%.Comment: IEEE Publication format, International Journal of Computer Science and Information Security, IJCSIS, Vol. 8 No. 1, April 2010, USA. ISSN 1947 5500, http://sites.google.com/site/ijcsis

    Chi_1 and Polarisation Asymmetries for Quarkonia at High Orders in Non-relativistic QCD

    Full text link
    We study doubly polarised asymmetries of c-cbar and b-bbar mesons in hadro- and photo-production at low transverse momentum in non-relativistic QCD to high orders in the relative velocity of the pair, v. We give the complete set of expressions required for the asymmetries up to order v^9. The asymmetries in the production of eta_{c,b} states are a stable measure of the polarised gluon densities. The asymmetries for chi_{c,b}, J/psi, psi', and the various Upsilon states are stringent tests of the NRQCD scaling relations.Comment: 21 pages LaTeX including 2 figure

    Signature of strong atom-cavity interaction on critical coupling

    Full text link
    We study a critically coupled cavity doped with resonant atoms with metamaterial slabs as mirrors. We show how resonant atom-cavity interaction can lead to a splitting of the critical coupling dip. The results are explained in terms of the frequency and lifetime splitting of the coupled system.Comment: 8 pages, 5 figure

    Bc spectroscopy in a quantum-chromodynamic potential model

    Full text link
    We have investigated BcB_c spectroscopy with the use of a quantum-chromodynamic potential model which was recently used by us for the light-heavy quarkonia. We give our predictions for the energy levels and the EE1 transition widths. We also find, rather surprisingly, that although BcB_c is not a light-heavy system, the heavy quark effective theory with the inclusion of the mb1m_b^{-1} and mb1lnmbm_b^{-1}\ln m_b corrections is as successful for BcB_c as it is for BB and BsB_s.Comment: 10 page ReVTeX pape

    Heavy Quarkonium Potential Model and the 1P1{}^1P_1 State of Charmonium

    Full text link
    A theoretical explanation of the observed splittings among the P~states of charmonium is given with the use of a nonsingular potential model for heavy quarkonia. We also show that the recently observed mass difference between the center of gravity of the 3PJ{}^3P_J states and the 1P1{}^1P_1 state of ccˉc\bar{c} does not provide a direct test of the color hyperfine interaction in heavy quarkonia. Our theoretical value for the mass of the 1P1{}^1P_1 state is in agreement with the experimental result, and its E1 transition width is 341.8~keV. The mass of the ηc\eta_c' state is predicted to be 3622.3~MeV.Comment: 15 page REVTEX documen
    corecore