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تسجيل مستخدم جديدChandra Analysis and Mass Estimation of the Lensing Cluster of Galaxies CL0024+17
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Naomi Ota
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We present a detailed analysis of Chandra X-ray observations of the lensing cluster of galaxies CL0024+17 at z=0.395. We found that the radial temperature profile is consistent with being isothermal out to ~600 kpc and that the average X-ray temperature is 4.47 (+0.83, -0.54) keV. The X-ray surface brightness profile is represented by the sum of extended emission centered at the central bright elliptical galaxy with a small core of 50 kpc and more extended emission which can be well described by a spherical beta-model with a core radius of about 210 kpc. Assuming the X-ray emitting gas to be in hydrostatic equilibrium, we estimated the X-ray mass within the arc radius and found it is significantly smaller than the strong lensing mass by a factor of about 2--3. We detected a strong redshifted iron K line in the X-ray spectrum from the cluster for the first time and find the metal abundance to be 0.76 (+0.37, -0.31) solar.
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We present the X-ray analysis and the mass estimation of the lensing cluster of galaxies CL0024+17 with Chandra. We found that the temperature profile is consistent with being isothermal and the average X-ray temperature is 4.47 (+0.83, -0.54) keV. T
he X-ray surface brightness profile is represented by the sum of emissions associated with the central three bright elliptical galaxies and the emission from intracluster medium (ICM) which can be well described by a spherical beta-model. Assuming the ICM to be in the hydrostatic equilibrium, we estimated the X-ray mass and found it is significantly smaller than the strong lensing mass by a factor of 3.
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