53,770 research outputs found

    Measuring the galaxy power spectrum with multiresolution decomposition -- II. diagonal and off-diagonal power spectra of the LCRS galaxies

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    The power spectrum estimator based on the discrete wavelet transform (DWT) for 3-dimensional samples has been studied. The DWT estimator for multi-dimensional samples provides two types of spectra with respect to diagonal and off-diagonal modes, which are very flexible to deal with configuration-related problems in the power spectrum detection. With simulation samples and mock catalogues of the Las Campanas redshift survey (LCRS), we show (1) the slice-like geometry of the LCRS doesn't affect the off-diagonal power spectrum with ``slice-like'' mode; (2) the Poisson sampling with the LCRS selection function doesn't cause more than 1-Ļƒ\sigma error in the DWT power spectrum; and (3) the powers of peculiar velocity fluctuations, which cause the redshift distortion, are approximately scale-independent. These results insure that the uncertainties of the power spectrum measurement are under control. The scatter of the DWT power spectra of the six strips of the LCRS survey is found to be rather small. It is less than 1-Ļƒ\sigma of the cosmic variance of mock samples in the wavenumber range 0.1<k<20.1 < k < 2 h Mpcāˆ’1^{-1}. To fit the detected LCRS diagonal DWT power spectrum with CDM models, we find that the best-fitting redshift distortion parameter Ī²\beta is about the same as that obtained from the Fourier power spectrum. The velocity dispersions Ļƒv\sigma_v for SCDM and Ī›\LambdaCDM models are also consistent with other Ļƒv\sigma_v detections with the LCRS. A systematic difference between the best-fitting parameters of diagonal and off-diagonal power spectra has been significantly measured. This indicates that the off-diagonal power spectra are capable of providing information about the power spectrum of galaxy velocity field.Comment: AAS LaTeX file, 41 pages, 10 figures included, accepted for publication in Ap

    Systematic Review of the Literature on Black and Minority Ethnic Communities in Sport and Physical Recreation

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    The Carnegie Research Institute was commissioned by Sporting Equals and the Sports Councils to conduct an independent systematic review of the literature on participation in sport and recreation by Black and minority ethnic (BME) communities. The brief was to focus on UK material from the past ten years, to compile an electronic, bibliographic database and use that evidence to assess the policy significance of existing knowledge in the drive to widen and increase participation. Although the field might still be considered under-researched over 300 items were identified. Judgements were made on the quality of the research on the basis of the methodological and theoretical soundness and the credibility of the link between the conclusions and the data. The various items were collated in an electronic, bibliographic database and coded as: substantive research of good quality; related public statistics and policy documents; and other related materials of interest. The research, policy and practice contained in this body of work is set within an expanding national and international framework of policy and legislation concerned with human rights and principles of equality. The Sports Councils and Sporting Equals have played a significant part in this through initiatives like the Equality Standard. They have not been acting in isolation, but have received support from other sports bodies with initiatives both to challenge discrimination and inequality and to promote participation and inclusion. Nonetheless, there still seems to be a measure of disconnection between research, sports policies and equality policies. Indeed, sports policies are sometimes based on limited representations of racism and so are inhibited in the way they address racial equality

    The long-range interactions between branes in diverse dimensions

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    We calculate the long-range interactions between two simple branes placed parallel at a separation in diverse dimensions via an effective field theory approach. We also compute for the first time the explicit long-range interaction between two D-branes with each carrying a world-volume non-abelian magnetic flux in three special cases, respectively. In particular, we demonstrate that the half-string creation between a D0_0-brane and a D8_8-brane continues to hold even in the present context, therefore lending further support to the previous assertion of this. Our computations re-raise also the issue in one case on whether so constructed (D0_0, D8_8) bound state is actually a marginal one.Comment: 28 pages, various discussions expanded and references adde

    Mathematical specifications of the Onboard Navigation Package (ONPAC) simulator (revision 1)

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    The mathematical theory of the computational algorithms employed in the onboard navigation package system is described. This system, which simulates an onboard navigation processor, was developed to aid in the design and evaluation of onboard navigation software. The mathematical formulations presented include the factorized UDU(T) form of the extended Kalman filter, the equations of motion of the user satellite, the user clock equations, the observation equations and their partial derivatives, the coodinate transformations, and the matrix decomposition algorithms

    Space for inclusion? The Construction of Sport and Leisure Spaces as Places for Migrant Communities

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    The research on which this paper is based started from the proposition that sport and leisure spaces can support processes of social inclusion (Amara et al., 2005), yet may also serve to exclude certain groups. As such, these spaces may be seen as contested and racialised places that shape behaviour. We shall use this paper not just to explore how those spaces are perceived by new migrants, but how those interpretations may vary with time and processes of social change. That involves examining how sport and leisure spaces are encoded in different ways, thereby affecting peopleā€™s experience, while at the same time recognising that their sport and leisure practices shape those social constructions. We argue that such an understanding is necessary to inform policies and practices that could promote the development of mutual and shared spaces rather than disconnected multiple occupations of spaces. Our goal is not only to contribute to the development of theory, but also to the debate that has counterposed multiculturalism and integrationism. Our recent systematic review, conducted for Sporting Equals and the sports councils (Long et al., 2009), synthesised literature on participation in sport and physical recreation by people from Black and Minority Ethnic Communities (BME) in the UK. That review identified a growing body of research, but one focussing primarily on the experiences of Black and Asian groupings. That has led us to turn to a consideration of new migrant communities. In this paper we shall be reporting on empirical research conducted with ā€˜new migrantsā€™ now living in Leeds

    Spin symmetry in Dirac negative energy spectrum in density-dependent relativistic Hartree-Fock theory

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    The spin symmetry in the Dirac negative energy spectrum and its origin are investigated for the first time within the density-dependent relativistic Hartree-Fock (DDRHF) theory. Taking the nucleus 16^{16}O as an example, the spin symmetry in the negative energy spectrum is found to be a good approximation and the dominant components of the Dirac wave functions for the spin doublets are nearly identical. In comparison with the relativistic Hartree approximation where the origin of spin symmetry lies in the equality of the scalar and vector potentials, in DDRHF the cancellation between the Hartree and Fock terms is responsible for the better spin symmetry properties and determines the subtle spin-orbit splitting. These conclusions hold even in the case when significant deviations from the G-parity values of the meson-antinucleon couplings occur.Comment: 13 pages, 7 figures, 1 table, accepted by Eur. Phys. J.
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