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We present the results of a gravitational lensing analysis of the bright $zs=2.957$ sub-millimeter galaxy (SMG), HERMES J105751.1+573027 found in {it Herschel}/SPIRE Science Demonstration Phase data from the Herschel Multi-tiered Extragalactic Survey (HerMES) project. The high resolution imaging available in optical and Near-IR channels, along with CO emission obtained with the Plateau de Bure Interferometer, allow us to precisely estimate the intrinsic source extension and hence estimate the total lensing magnification to be $mu=10.9pm 0.7$. We measure the half-light radius $R_{rm eff}$ of the source in the rest-frame Near-UV and $V$ bands that characterize the unobscured light coming from stars and find $R_{rm eff,*}= [2.0 pm 0.1]$ kpc, in good agreement with recent studies on the Submillimeter Galaxy population. This lens model is also used to estimate the size of the gas distribution ($R_{rm eff,gas}= [1.1pm0.5]$) kpc by mapping back in the source plane the CO (J=5-4) transition line emission. The lens modeling yields a relatively large Einstein radius $R_{rm Ein}= 4farcs10 pm 0farcs02$, corresponding to a deflector velocity dispersion of [$483pm 16] ,kms$. This shows that HERMES J105751.1+573027 is lensed by a {it galaxy group-size} dark matter halo at redshift $zlsim 0.6$. The projected dark matter contribution largely dominates the mass budget within the Einstein radius with $f_{rm dm}(<R_{rm Ein})sim 80%$. This fraction reduces to $f_{rm dm}(<R_{rm eff,G1}simeq 4.5kpc)sim 47%$ within the effective radius of the main deflecting galaxy of stellar mass $M_{rm *,G1}=[8.5pm 1.6] times 10^{11}msun$. At this smaller scale the dark matter fraction is consistent with results already found for massive lensing ellipticals at $zsim0.2$ from the SLACS survey.
Mass models for a sample of 18 late-type dwarf and low surface brightness galaxies show that in almost all cases the contribution of the stellar disks to the rotation curves can be scaled to explain most of the observed rotation curves out to two or
We present a list of 13 candidate gravitationally lensed submillimeter galaxies (SMGs) from 95 square degrees of the Herschel Multi-tiered Extragalactic Survey, a surface density of 0.14pm0.04deg^{-2}. The selected sources have 500um flux densities (
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Spitzer spectroscopy has revealed that ~80% of submm galaxies (SMGs) are starburst (SB) dominated in the mid-infrared. Here we focus on the remaining ~20% that show signs of harboring powerful active galactic nuclei (AGN). We have obtained Spitzer-IR
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