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AMiBA: scaling relations between the integrated Compton-y and X-ray derived temperature, mass, and luminosity

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 نشر من قبل Chih-Wei Locutus Huang
 تاريخ النشر 2009
  مجال البحث فيزياء
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We investigate the scaling relations between the X-ray and the thermal Sunyaev-Zeldovich Effect (SZE) properties of clusters of galaxies, using data taken during 2007 by the Y.T. Lee Array for Microwave Background Anisotropy (AMiBA) at 94 GHz for the six clusters A1689, A1995, A2142, A2163, A2261, and A2390. The scaling relations relate the integrated Compton-y parameter Y_{2500} to the X-ray derived gas temperature T_{e}, total mass M_{2500}, and bolometric luminosity L_X within r_{2500}. Our results for the power-law index and normalization are both consistent with the self-similar model and other studies in the literature except for the Y_{2500}-L_X relation, for which a physical explanation is given though further investigation may be still needed. Our results not only provide confidence for the AMiBA project but also support our understanding of galaxy clusters.

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