A Dusty Mg II absorber Associated with the Quasar SDSS J003545.13+011441.2

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We report on a dusty Mg II absorber associated with the quasar SDSSJ003545.13+011441.2 (hereafter J0035+0114) at z=1.5501, which is the strongest one among the three Mg II absorbers along the sight line of quasar. The two low redshift intervening absorbers are at z=0.7436, 0.5436, respectively. Based on the photometric and spectroscopic data of Sloan Digital Sky Survey (hereafter SDSS), we infer the rest frame color excess E() due to the associated dust is more than 0.07 by assuming a Small Magellanic Cloud (hereafter SMC) type extinction curve. Our follow-up moderate resolution spectroscopic observation at the 10-m Keck telescope with the ESI spectrometer enable us to reliably identify most of the important metal elements, such as Zn, Fe, Mn, Mg, Al, Si, Cr, and Ni in the associated system. We measure the column density of each species and detect significant dust depletion. In addition, we develop a simulation technique to gauge the significance of 2175-Å dust absorption bump on the SDSS quasar spectra. By using it, we analyze the SDSS spectrum of J0035+0114 for the presence of a associated 2175-Å extinction feature and report a tentative detection at 2σ significant level.