A Compton Thick AGN Powering the Hyperluminous Infrared Galaxy IRAS 00182--7112

We present X-ray observations of the Hyperluminous Infrared Galaxy (HLIRG) IRAS 00182--7112 (F00183--7111) obtained using the XMM-Newton EPIC camera. A luminous hard X-ray source co-incident with the nucleus is revealed, along with weaker soft X-ray emission which may be extended or offset from the hard. The EPIC spectrum is extremely flat and shows Fe K$\alpha$ emission with very high equivalent width: both are typical characteristics of a buried, Compton--thick AGN which is seen only in scattered light. Perhaps the most remarkable characteristic of the spectrum is that the Fe K$\alpha$ line energy is that of He-like iron, making IRAS 00182--7112 the first hidden AGN known to be dominated by ionized, Compton thick reflection. Taking an appropriate bolometric correction we find that this AGN could easily dominate the FIR energetics. The nuclear reflection spectrum is seen through a relatively cold absorber with column density consistent with recent Spitzer observations. The soft X-ray emission, which may be thermal in nature and associated with star-forming activity, is seen unabsorbed. The soft X-rays and weak PAH features both give estimates of the star formation rate $\sim 300 M_{\odot}$ yr$^{-1}$, insufficient to power the FIR emission and supportive of the idea that this HLIRG is AGN-dominated.Comment: 6 pages, 3 figures, accepted for publication in MNRAS Letter

Opportunity and accounts consolidation conditions

This paper presents some aspects regarding competition and harmonization in European Union fiscal policy, especially after the last enlargement on 2007. The problem of tax harmonization is connected with tax competition in the context of increasing capital mobility between different countries. Using a panel data for EU countries, analyzed on 1995- 2004, we find significant correlations between the implicit tax rate of business income and corporation profits and the budget deficit, public debt, GDP per capita and the degree of openness of countries, the last variable is used as a proxy for capital mobility.fiscal policy, tax competition, tax harmonization.

The Distribution and Cosmic Density of Relativistic Iron Lines in Active Galactic Nuclei

X-ray observations of several active galactic nuclei show prominent iron K-shell fluorescence lines that are sculpted due to special and general relativistic effects. These observations are important because they probe the space-time geometry close to distant black holes. However, the intrinsic distribution of Fe line strengths in the cosmos has never been determined. This uncertainty has contributed to the controversy surrounding the relativistic interpretation of the emission feature. Now, by making use of the latest multi-wavelength data, we show theoretical predictions of the cosmic density of relativistic Fe lines as a function of their equivalent width and line flux. We are able to show unequivocally that the most common relativistic iron lines in the universe will be produced by neutral iron fluorescence in Seyfert galaxies and have equivalent widths < 100 eV. Thus, the handful of very intense lines that have been discovered are just the bright end of a distribution of line strengths. In addition to validating the current observations, the predicted distributions can be used for planning future surveys of relativistic Fe lines. Finally, the predicted sky density of equivalent widths indicate that the X-ray source in AGNs can not, on average, lie on the axis of the black hole.Comment: 12 pages, 3 figures, accepted by ApJ Letter

Relativistic reflection from accretion disks in the population of Active Galactic Nuclei at z=0.5-4

We report the detection of relativistically broadened iron K alpha emission in the X-ray spectra of AGN detected in the 4Ms CDF-S. Using the Bayesian X-ray analysis (BXA) package, we fit 199 hard band (2-7 keV) selected sources in the redshift range z=0.5--4 with three models: (i) an absorbed power-law, (ii) the first model plus a narrow reflection component, and (iii) the second model with an additional relativistic broadened reflection. The Bayesian evidence for the full sample of sources selects the model with the additional broad component as being 10^5 times more probable to describe the data better than the second model. For the two brightest sources in our sample, CID 190 (z=0.734) and CID 104 (z=0.543), BXA reveals the relativistic signatures in the individual spectra. We estimate the fraction of sources containing a broad component to be 54^{+35}_{-37}% (107/199 sources). Considering that the low signal-to-noise ratio of some spectra prevents the detection of the broad iron K alpha line, we infer an intrinsic fraction with broad emission of around two thirds. The detection of relativistic signatures in the X-ray spectra of these sources suggests that they are powered by a radiatively efficient accretion disk. Preliminary evidence is found that the spin of the black hole is high, with a maximally spinning Kerr BH model (a=1) providing a significantly better fit than a Schwarzschild model (a=0). Our analysis demonstrate the potential of X-ray spectroscopy to measure this key parameter in typical SMBH systems at the peak of BH growth.Comment: 10 pages, 5 figures, accepted for publication in MNRA

Iron K line emission in AGN: observations

Iron K-alpha lines are key diagnostics of the central regions of AGN. Their profiles indicate that they are formed deep in the potential well of the central black hole, where extreme broadening and red shift occur. The profiles are most easily reproducible in an accretion disk: the lack of significant emission blue-ward of the rest energy is difficult produce in other geometries. In one source an apparent (and perhaps variable) absorption feature in the red wing of the line may represent rare evidence for inflow onto the black hole. Sample analysis has defined the mean properties, showing a strong concentration of the emission in the central regions and face-on accretion disks, at least in Seyfert 1 galaxies. Surprising results have been obtained from examination of the line variability. Strong profile changes may be accounted for by changes in the illumination pattern of the central, relativistic part of the disk. In at least the case of MCG-6-30-15, there is evidence for emission from within 6 R_g, possibly indicating a spinning black hole. Developing an understanding of these complex changes has the potential to reveal the geometry and kinematics of the inner few gravitational radii around extragalactic black holes.Comment: 10 pages, 3 figures, to appear in "Proceedings of X-ray Astronomy '99 - Stellar Endpoints, AGN and the Diffuse Background". Also available via http://lheawww.gsfc.nasa.gov/users/nandra/home.htm

Bench-to-bedside review: Erythropoietin and its derivatives as therapies in critical care

Author can archive publisher's pdf. Free via Creative Commons: CC-BENCHTOBEDSIDE-2.0. © 2012 BioMed Central Ltd

Dynamics of a spherical object of uniform density in an expanding universe

We present Newtonian and fully general-relativistic solutions for the evolution of a spherical region of uniform interior density \rho_i(t), embedded in a background of uniform exterior density \rho_e(t). In both regions, the fluid is assumed to support pressure. In general, the expansion rates of the two regions, expressed in terms of interior and exterior Hubble parameters H_i(t) and H_e(t), respectively, are independent. We consider in detail two special cases: an object with a static boundary, H_i(t)=0; and an object whose internal Hubble parameter matches that of the background, H_i(t)=H_e(t). In the latter case, we also obtain fully general-relativistic expressions for the force required to keep a test particle at rest inside the object, and that required to keep a test particle on the moving boundary. We also derive a generalised form of the Oppenheimer-Volkov equation, valid for general time-dependent spherically-symmetric systems, which may be of interest in its own right.Comment: 22 pages, 4 figures, submitted to PR

PENGARUH KINERJA KEUANGAN TERHADAP HARGA SAHAM PERUSAHAAN PROPERTY AND REAL ESTATE YANG TERDAFTAR DI BURSA EFEK INDONESIA (BEI)

Penelitianinibertujuanuntuk mengetahui pengaruh kinerja keuangan yang diukurmenggunakanCurrent Ratio, Return On Asset, Return On Equity, Debt Equity Ratio, danPrice Earning Ratioterhadap harga sahamperusahaanproperty and real estateyang terdaftar di Bursa Efek Indonesia periode tahun 2011-2015. Jenis penelitian yang dilakukan yaitu penelitian kausal komparatif (Causal-Comparatif Research) yang menjelaskan hubungan sebab akibat antara dua variabel atau lebih. Pengambilan sampel menggunakan metodepurposive samplingdari sebanyak 48 perusahaan property and real estateyang terdaftar di Bursa Efek Indonesia (BEI), sehingga diperoleh 10 perusahaan yang digunakan sebagai sampel pada penelitian. Teknikanalisis data yang digunakan adalah analisis deskriptif dan regresi linier bergandadenganalatbantu SPSS (Statistical Package for Social Sciences) 20. Hasil uji kelayakan model (uji F) menunjukkan bahwa model penelitian layak digunakan untuk penelitian selanjutnya. Pengujian hipotesis secara parsial (uji t) menunjukkan variabel Current Ratio (CR) berpengaruh positif tidak signifikan terhadap harga saham, Return On Assets (ROA) berpengaruh positif signifikan terhadap harga saham, Return On Equity(ROE) positif signifikan terhadap harga saham, Debt Equity Ratio (DER) negatif signifikan terhadap harga saham, danPrice Earning Ratio (PER) positif signifikan terhadap harga saham. Kata kunci :Current ratio, return on assets, return on equity, debt equity ratio, price earning ratio, harga saham