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Magellan Spectroscopy of the Galaxy Cluster RX J1347.5-1145: Redshift Estimates for the Gravitationally Lensed Arcs

Swara Ravindranath·Luis C. Ho
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Abstract

We present imaging and spectroscopic observations of the gravitationally lensed arcs in the field of RX J1347.5-1145, the most X-ray luminous galaxy cluster known. Based on the detection of the [OII] 3727 emission line, we confirm that the redshift of one of the arcs is z = 0.806. Its color and [OII] line strength are consistent with those of distant, actively star forming galaxies. In a second arc, we tentatively identify a pair of absorption lines superposed on a red continuum; the lines are consistent with Ca II H & K at z = 0.785. We detected a faint blue continuum in two additional arcs, but no spectral line features could be measured. We establish lower limits to their redshifts based on the absence of [OII] emission, which we argue should be present and detectable in these objects. Redshifts are also given for a number of galaxies in the field of the cluster.

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Swara Ravindranath, Luis C. Ho. 2002-06-24. Magellan Spectroscopy of the Galaxy Cluster RX J1347.5-1145: Redshift Estimates for the Gravitationally Lensed Arcs. https://doi.org/10.1086/342124

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