1,289 research outputs found

    Reforming India’s Fiscal Transfer System : Resolving Vertical and Horizontal Imbalances

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    Two central problems in a fiscal transfer systemrelate to resolving vertical and horizontal imbalances. In the context of the setting of the 13th Finance Commission, this paper looks at the methodological background of fiscal transfers followed by recent Finance Commissions in India, particularly the Twelfth Finance Commission (TFC). It is noted that in India, there is long - term stability in the share of states after transfers in the combined revenues of the centre and the states. It is argued that this stability depends on linking the share of states in the transfers, particularly tax devolution with the difference in the buoyancies of central and states taxes. In the context of horizontal imbalance, it is argued that some of the recent Finance Commissions have implicitly followed an axiomatic approach to tax devolution and brought in some normative elements in determining grants. In spite of large difference in fiscal capacities, a high degree of equalization has been achieved. It is shown, for example, that in the case of TFC recommended transfers, nearly 88 percent of needed equalization was achieved while devoting 50 percent of transfers to resolving vertical imbalance. Amethodology is also developed to determine weights of vertical and equalizing components of transfers through devolution. In the case of the Twelfth Finance Commission, the horizontal component of tax devolution is strengthened by a scheme of equalizing health and education grants.fiscal transfer system, vertical imbalance, horizontal imbalance, Twelfth Finance Commission

    Lyapunov Exponents without Rescaling and Reorthogonalization

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    We present a new method for the computation of Lyapunov exponents utilizing representations of orthogonal matrices applied to decompositions of M or MM_trans where M is the tangent map. This method uses a minimal set of variables, does not require renormalization or reorthogonalization, can be used to efficiently compute partial Lyapunov spectra, and does not break down when the Lyapunov spectrum is degenerate.Comment: 4 pages, no figures, uses RevTeX plus macro (included). Phys. Rev. Lett. (in press

    Remarks on non-gaussian fluctuations of the inflaton and constancy of \zeta outside the horizon

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    We point out that the non-gaussianity arising from cubic self interactions of the inflaton field is proportional to \xi N_e where \xi ~ V"' and N_e is the number of e-foldings from horizon exit till the end of inflation. For scales of interest N_e = 60, and for models of inflation such as new inflation, natural inflation and running mass inflation \xi is large compared to the slow roll parameter \epsilon ~ V'^{2}. Therefore the contribution from self interactions should not be outrightly ignored while retaining other terms in the non-gaussianity parameter f_{NL}. But the N_e dependent term seems to imply the growth of non-gaussianities outside the horizon. Therefore we briefly discuss the issue of the constancy of correlations of the curvature perturbation \zeta outside the horizon. We then calculate the 3-point function of the inflaton fluctuations using the canonical formalism and further obtain the 3-point function of \zeta_k. We find that the N_e dependent contribution to f_{NL} from self interactions of the inflaton field is cancelled by contributions from other terms associated with non-linearities in cosmological perturbation theory.Comment: 16 pages, Minor changes, matches the published version. v3: Minor typo correcte

    On the Weakening of Chromospheric Magnetic Field in Active Regions

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    Simultaneous measurement of line-of-sight (LOS) magnetic and velocity fields at the photosphere and chromosphere are presented. Fe I line at λ6569\lambda6569 and HαH_{\alpha} at λ6563\lambda6563 are used respectively for deriving the physical parameters at photospheric and chromospheric heights. The LOS magnetic field obtained through the center-of-gravity method show a linear relation between photospheric and chromospheric field for field strengths less than 700 G. But in strong field regions, the LOS magnetic field values derived from HαH_{\alpha} are much weaker than what one gets from the linear relationship and also from those expected from the extrapolation of the photospheric magnetic field. We discuss in detail the properties of magnetic field observed in HαH_{\alpha} from the point of view of observed velocity gradients. The bisector analysis of HαH_{\alpha} Stokes II profiles show larger velocity gradients in those places where strong photospheric magnetic fields are observed. These observations may support the view that the stronger fields diverge faster with height compared to weaker fields.Comment: accepted for publication in Ap

    Spatial synchronization and extinction of species under external forcing

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    We study the interplay between synchronization and extinction of a species. Using a general model we show that under a common external forcing, the species with a quadratic saturation term in the population dynamics first undergoes spatial synchronization and then extinction, thereby avoiding the rescue effect. This is because the saturation term reduces the synchronization time scale but not the extinction time scale. The effect can be observed even when the external forcing acts only on some locations provided there is a synchronizing term in the dynamics. Absence of the quadratic saturation term can help the species to avoid extinction.Comment: 4 pages, 2 figure

    ASMOOTH: A simple and efficient algorithm for adaptive kernel smoothing of two-dimensional imaging data

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    An efficient algorithm for adaptive kernel smoothing (AKS) of two-dimensional imaging data has been developed and implemented using the Interactive Data Language (IDL). The functional form of the kernel can be varied (top-hat, Gaussian etc.) to allow different weighting of the event counts registered within the smoothing region. For each individual pixel the algorithm increases the smoothing scale until the signal-to-noise ratio (s.n.r.) within the kernel reaches a preset value. Thus, noise is suppressed very efficiently, while at the same time real structure, i.e. signal that is locally significant at the selected s.n.r. level, is preserved on all scales. In particular, extended features in noise-dominated regions are visually enhanced. The ASMOOTH algorithm differs from other AKS routines in that it allows a quantitative assessment of the goodness of the local signal estimation by producing adaptively smoothed images in which all pixel values share the same signal-to-noise ratio above the background. We apply ASMOOTH to both real observational data (an X-ray image of clusters of galaxies obtained with the Chandra X-ray Observatory) and to a simulated data set. We find the ASMOOTHed images to be fair representations of the input data in the sense that the residuals are consistent with pure noise, i.e. they possess Poissonian variance and a near-Gaussian distribution around a mean of zero, and are spatially uncorrelated.Comment: 9 pages, 5 figures, to be published in MNRA

    Deep ROSAT-HRI observations of the NGC 1399/NGC 1404 region: morphology and structure of the X-ray halo

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    We present the analysis of a deep (167 ks) ROSAT HRI observation of the cD galaxy NGC 1399 in the Fornax cluster. Using both HRI and, at larger radii, archival PSPC data, we find that the radial behavior of the X-ray surface brightness profile is not consistent with a simple Beta model and suggests instead three distinct components. We use a multi-component bidimensional model to study in detail these three components that we identify respectively with the cooling flow region, the galactic and the cluster halo. From these data we derive a binding mass distribution in agreement with that suggested by optical dynamical indicators, with an inner core dominated by luminous matter and an extended dark halo differently distributed on galactic and cluster scales. The HRI data and a preliminary analysis of Chandra public data, allow us to detect significant density fluctuations in the halo. We discuss possible non-equilibrium scenarios to explain the hot halo structure, including tidal interactions with neighboring galaxies, ram stripping from the intra-cluster medium and merging events. In the innermost region of NGC 1399, the comparison between the X-ray and radio emission suggests that the radio emitting plasma is displacing and producing shocks in the hot X-ray emitting gas. We found that the NGC 1404 halo is well represented by a single symmetric Beta model and follows the stellar light profile within the inner 8 kpc. The mass distribution is similar to the `central' component of the NGC 1399 halo. At larger radii ram pressure stripping from the intra-cluster medium produces strong asymmetries in the gas distribution. Finally we discuss the properties of the point source population finding evidence of correlation between the source excess and NGC 1399.Comment: 34 pages in aastex5.0 format, including 28 B&W and 4 color figures. Uses LaTex packages: subfigure, lscape and psfig. Accepted for publication in ApJ. High resolution version can be found at: http://www.na.astro.it/~paolillo/publications.htm
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