We present spatially resolved Atacama Large Millimeter/submillimeter Array (ALMA) 870 μm dust continuum maps of six massive, compact, dusty star-forming galaxies at z∼2.5. These galaxies are selected for their small rest-frame optical sizes (r 1.6 e,F160W kpc) and high stellar mass densities that suggest that they are direct progenitors of compact quiescent galaxies at z∼2. The deep observations yield high far-infrared (FIR) luminosities of =- L L 10 IR 12.3 12.8 and star formation rates (SFRs) of SFR=200-700 M e yr −1 , consistent with those of typical star-forming "main sequence" galaxies. The high spatial resolution (FWHM∼0 12-0 18) ALMA and Hubble Space Telescope photometry are combined to construct deconvolved, mean radial profiles of their stellar mass and (UV+IR) SFR. We find that the dusty, nuclear IR-SFR overwhelmingly dominates the bolometric SFR up to r∼5 kpc, by a factor of over 100× from the unobscured UV-SFR. Furthermore, the effective radius of the mean SFR profile (r 1 e,SFR kpc) is ∼30% smaller than that of the stellar mass profile. The implied structural evolution, if such nuclear starburst last for the estimated gas depletion time of Δt=±100 Myr, is a 4× increase of the stellar mass density within the central 1 kpc and a 1.6× decrease of the half-mass-radius. This structural evolution fully supports dissipation-driven, formation scenarios in which strong nuclear starbursts transform larger, star-forming progenitors into compact quiescent galaxies.

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Fermilab experiment E835 has measured the cross section for the reaction (p) over barp --> e(+)e(-) at s = 11.63, 12.43, 14.40 and 18.22 GeV2. From the analysis of the 66 observed events new high-precision measurements of the proton magnetic form factor are obtained. (C) 2003 Published by Elsevier Science B.V

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