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Using a sample of 229618 narrow emission-line galaxies, we have determined the normal star formation histories (SFHs) for galaxies with different activity types: star forming galaxies (SFGs), transition type objects (TOs), Seyfert 2s (Sy2s) and LINERs. We find that the variation of the SFH with the activity type is explained by the mass of the galaxies and the importance of their bulge: the LINERs reside in massive early-type galaxies, the Sy2s and TOs are hosted by intermediate mass galaxies with intermediate morphological types, and the SFGs are found in lower mass late-type spirals. Except for the Sy2s, the more massive galaxies formed the bulk of their stars more rapidly than the less massive ones. The Sy2s formed their stars more slowly and show presently an excess in star formation. We have also found that the maximum in star formation rate in the past increases with the virial mass within the aperture (VMA), the VMA increasing from the SFGs to the TOs, to the Sy2s, culminating in the LINERs. This correlation suggests that the bulges and the supermassive black holes at the center of galaxies grow in parallel, in good agreement with the M(BH)-sigma relation.
Deep observations of galaxy outskirts reveal faint extended stellar components (ESCs) of streams, shells, and halos, which are ghostly remnants of the tidal disruption of satellite galaxies. We use cosmological galaxy formation simulations in Cold Da
Deeply virtual Compton scattering (DVCS) and timelike Compton scattering (TCS) leading twist amplitudes are intimately related thanks to their analytic properties as a function of $Q^2$. We exploit this feature to use Compton form factors previously
As the numbers of submissions to conferences grow quickly, the task of assessing the quality of academic papers automatically, convincingly, and with high accuracy attracts increasing attention. We argue that studying interpretable dimensions of thes
Planck data has not found the smoking gun of non-Gaussianity that would have necessitated consideration of inflationary models beyond the simplest canonical single field scenarios. This raises the important question of what these results do imply for
The diagnostic age versus mass-to-light ratio diagram is often used in attempts to constrain the shape of the stellar initial mass function, and the stability and the potential longevity of extragalactic young to intermediate-age massive star cluster