The X-ray Fundamental Plane and LX−TL_X-T Relation of Clusters of Galaxies

We analyze the relations among central gas density, core radius, and temperature of X-ray clusters by plotting the observational data in the three-dimensional ($\log \rho_0$, $\log R$, and $\log T$) space and find that the data lie on a 'fundamental plane'. Its existence implies that the clusters form a two-parameter family. The data on the plane still has a correlation and form a band on the plane. The observed relation $L_{\rm X} \propto T^3$ turns out to be the cross section of the band perpendicular to the major axis, while the major axis is found to describe the virial density. We discuss implications of this two-parameter family nature of X-ray clusters.Comment: 7 pages, 2 figures. To be published in ApJ Letter

Modulation Mechanism of TeV, GeV, and X-ray Emission in LS5039

The emission mechanism of the gamma-ray binary LS5039 in energy bands of TeV, GeV, and X-ray is investigated. Observed light curves in LS5039 show that TeV and GeV fluxes anticorrelate and TeV and X-ray fluxes correlate. However, such correlated variations have not been explained yet reasonably at this stage. Assuming that relativistic electrons are injected constantly at the location of the compact object as a point source, and that they lose energy only by the inverse Compton (IC) process, we calculate gamma-ray spectra and light curves by the Monte Carlo method, including the full electromagnetic cascade process. Moreover, we calculated X-ray spectra and light curves by using the resultant electron distribution. As a result, we are able to reproduce qualitatively spectra and light curves observed by HESS, Fermi, and Suzaku for the inclination angle i = 30 dig and the index of injected electron distribution p = 2.5. We conclude that TeV-GeV anticorrelation is due to anisotropic IC scattering and anisotropic gamma-gamma absorption, and that TeV-X correlation is due to the dependence of IC cooling time on orbital phases. In addition, the constraint on the inclination angle implies that the compact object in LS5039 is a black hole.Comment: 27 pages, 7 figures, published in The Astrophysical Journa

Aerodynamic investigation of an air-cooled axial-flow turbine. Part 2: Rotor blade tip-clearance effects on overall turbine performance and internal gas flow conditions: Experimental results and prediction methods

Total turbine blade performance was investigated while changing the blade tip clearance in three ways. The internal flow at the moving blade outlet point was measured. Experimental results were compared with various theoretical methods. Increased blade clearance leads to decreased turbine efficiency