15,677 research outputs found

    Double-lepton polarization asymmetries in the (B -> K l^+ l^-) decay beyond the Standard Model

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    General expressions for the double-lepton polarizations in the (B -> K l^+ l^-) decay are obtained, using model independent effective Hamiltonian, including all possible interactions. Correlations between the averaged double-lepton polarization asymmetries and the branching ratio, as well as, the averaged single-lepton polarization asymmetry are studied. It is observed that, study of the double-lepton polarization asymmetries can serve as a good test for establishing new physics beyond the Standard Model.Comment: 21 pages, 18 figures, LaTeX formatte

    Detection of anti-correlated hard X-ray time lag in Cygnus X-3

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    The wide-band X-ray spectra of the high mass X-ray binary Cygnus X-3 exhibits a pivoting behavior in the `low' (as well as `hard') state, correlated to the radio emission. The time scale of the soft and hard X-rays' anti-correlation, which gave rise to the pivoting feature, was found to be less than a day from the monitoring observations by RXTE--ASM and CGRO--BATSE. In this Letter we report the detection of a lag of ≲\lesssim 1000s in the anti-correlation of the hard X-ray emission (20--50 keV) to that of the soft X-ray emission (2--7 keV), which may be attributed to the viscous time scale of flow of matter in the accretion disk. This suggests the geometrical picture of a truncated accretion disc with a Compton cloud inside the disc, the relative sizes of which determine the spectral shape. Any change in the disc structure will take place in a viscous time scale, with corresponding anti-correlated change in the Compton cloud. We also report the pivoting in the spectra in one span of a pointed observation when an episode of the rearranging of the accretion system is serendipitously observed. This is the first such observation of hard X-ray delay seen in the persistent Galactic microquasars, within the precincts of the hard state.Comment: Accepted in The Astrophysical Journal (Letters): in pres

    Isgur-Wise function in a QCD potential model with coulombic potential as perturbation

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    We study heavy light mesons in a QCD inspired quark model with the Cornell potential−4αS3r+br+c-\frac{4\alpha_{S}}{3r}+br+c. Here we consider the linear term brbr as the parent and −4αS3r+c-\frac{4\alpha_{S}}{3r}+c i.e.the Coloumbic part as the perturbation.The linear parent leads to Airy function as the unperturbed wavefunction. We then use the Dalgarno method of perturbation theory to obtain the total wavefunction corrected upto first order with Coulombic peice as the perturbation.With these wavefunctions, we study the Isgur-Wise function and calculate its slope and curvature.Comment: paper has been modified in Airy functions calculation upto o(r^3

    Evolution of X-ray spectra of Cygnus X-3 with radio flares

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    Cygnus X-3, among the X-ray binaries, is one of the brightest in the radio band, repeatedly exhibiting huge radio flares. The X-ray spectra shows two definite states, low (correspondingly hard) and high (correspondingly soft). During the hard state the X-ray spectra shows a pivoting behaviour correlated to the radio emission. In the high state the X-ray spectra shows a gamut of behaviour which controls the radio flaring activity of the source. The complete evolution of the X-ray spectra along with the radio flaring activity is reported here, for the first time for this source.Comment: Bibliography has been correctly adde

    An analysis of the Isgur-Wise Function and its derivatives within a Heavy-Light QCD Quark Model

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    In determining the mesonic wave function from QCD inspired potential model, if the linear confinement term is taken as parent (with columbic term as perturbation), Airy's function appears in the resultant wave function - which is an infinite series. In the study of Isgur-Wise function (IWF) and its derivatives with such a wave function, the infinite upper limit of integration gives rise to divergence. In this paper, we have proposed some reasonable cut-off values for the upper limit of such integrations and studied the subsequent effect on the results. We also study the sensitivity of the order of polynomial approximation of the infinite Airy series in calculating the derivatives of IWF.Comment: 14 pages,6 tables 8 figure

    Emergence of a non-scaling degree distribution in bipartite networks: a numerical and analytical study

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    We study the growth of bipartite networks in which the number of nodes in one of the partitions is kept fixed while the other partition is allowed to grow. We study random and preferential attachment as well as combination of both. We derive the exact analytical expression for the degree-distribution of all these different types of attachments while assuming that edges are incorporated sequentially, i.e., a single edge is added to the growing network in a time step. We also provide an approximate expression for the case when more than one edge are added in a time step. We show that depending on the relative weight between random and preferential attachment, the degree-distribution of this type of network falls into one of four possible regimes which range from a binomial distribution for pure random attachment to an u-shaped distribution for dominant preferential attachment

    Looking for the Top-squark at the Tevatron with four jets

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    The scalar partner of the top quark is relatively light in many models of supersymmetry breaking. We study the production of top squarks (stops) at the Tevatron collider and their subsequent decay through baryon-number violating couplings such that the final state contains no leptons. Performing a detector-level analysis, we demonstrate that, even in the absence of leptons or missing energy, stop masses upto 210 \gev/c^2 can be accessible at the Tevatron.Comment: 4 pages, 4 embedded figures, RevTe

    Effects of polarisation on study of anomalous VVH interactions at a Linear Collider

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    We investigate the use of beam polarisation as well as final state τ\tau polarisation effects in probing the interaction of the Higgs boson with a pair of heavy vector bosons in the process e+e−→ffˉHe^+ e^- \to f \bar f H, where ff is any light fermion. The sensitivity of the International Linear Collider (ILC) operating at s=500\sqrt s=500 GeV, to such VVHVVH(V=W/ZV = W/Z) couplings is examined in a model independent way. The effects of ISR and beamstrahlung are discussed.Comment: To appear in the proceedings of 2007 International Linear Collider Workshop (LCWS07 and ILC07), Hamburg, Germany, 30 May - 3 Jun 2007. 4 pages, LaTeX, 1 eps figure. requires ilcws07.cls. included in submissio

    Resource Devolution from the Centre to States: Enhancing the Revenue Capacity of States for Implementation of Essential Health Interventions

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    Access to adequate health care services is an important component of empowering people with human capital. This, however, can be achieved only when the spending on health care is adequate and delivery systems efficient. Improving health indicators is an important component of the Millennium Development Goals (MDGs) set by the United Nations. There are also important targets on health status achievements set for the Tenth Plan. The Common Minimum Programme of the ruling UPA government also seeks to increase the public expenditure by the Centre and States on health and family welfare schemes from the present level of less than 1% to 2%-3% of the gross domestic product (GDP). The provision of health and family welfare services falls in the realm of concurrent responsibility of the Centre and the States, but the latter have a predominant role in the delivery of these services. However, fiscal pressures at the State level lead to compression of expenditures by the State Governments resulting in an increase in Central financing of these services, particularly for some prioritized programmes implemented through the Centre and Centrally sponsored schemes. Thus, over 85% of the public expenditure on medical and public health is incurred by the State Governments, though the proportion of financing the expenditure by the State Governments is lower. This paper identifies the resource gap between the desired and the actual health expenditure in 15 major States in India (14 large, non-special category States and Assam), and highlights the extent to which the gap can be reduced by augmenting resources at the State level. Further, it estimates the resource gap that cannot be met through States’ own resources and therefore, requires Central transfers. The design of Central transfers needed for meeting the required health expenditure of various States is also discussed.Federal Transfers to Provinces; Public Expenditure on Health
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