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Imaging the z=0.9 Absorbing Cloud toward 1830-211

C. L. Carilli·K. M. Menten·M. J. Reid·M. Rupen·M. Claussen
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Abstract

We present spectroscopic imaging observations of the molecular and HI 21cm absorbing cloud at z = 0.885 toward the `Einstein ring' radio source PKS 1830-211. We derive a cloud size between 10 h^{-1} pc and 600 h^{-1} pc, and M(H_2) > 2.6x10^{4} h^{-2} Msolar. The temperature of the ambient radiation field is 4.5+/-0.9 K, consistent with the microwave background temperature at z = 0.885. The velocity difference for absorption on opposite sides of the ring is -146 km s^{-1}, which is consistent with the galaxian rotation velocity derived from gravitational lens models.

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C. L. Carilli, K. M. Menten, M. J. Reid, M. Rupen, M. Claussen. 1998-01-15. Imaging the z=0.9 Absorbing Cloud toward 1830-211. https://arxiv.org/abs/astro-ph/9801157

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