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Chandra Analysis and Mass Estimation of the Lensing Cluster of Galaxies CL0024+17

Naomi Ota·Etienne Pointecouteau·Makoto Hattori·Kazuhisa Mitsuda
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Abstract

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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Naomi Ota, Etienne Pointecouteau, Makoto Hattori, Kazuhisa Mitsuda. 2003-10-08. Chandra Analysis and Mass Estimation of the Lensing Cluster of Galaxies CL0024+17. https://doi.org/10.1086/380438

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