author={Jason Tumlinson and Adrian L. Malec and Robert F Carswell and Michael Murphy and Ruth Buning and N. Milutinovic and Sara L Ellison and J. Xavier Prochaska and Regina Jorgenson and Wim Ubachs and Arthur M. Wolfe},
  journal={The Astrophysical Journal},
We report two detections of deuterated molecular hydrogen (HD) in QSO absorption-line systems at z>2. Toward J2123–0500, we find N(HD) =13.84 ± 0.2 for a sub-Damped Lyman Alpha system (DLA) with metallicity 0.5Z ☉ and N(H2) = 17.64 ± 0.15 at z = 2.0594. Toward FJ0812+32, we find N(HD) =15.38 ± 0.3 for a solar-metallicity DLA with N(H2) = 19.88 ± 0.2 at z = 2.6265. These systems have ratios of HD to H2 above that observed in dense clouds within the Milky Way disk and apparently consistent with a… Expand

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