Early-type galaxies are thought to be among the oldest known stellar systems, and as such have experienced the full diversity of evolutionary mechanisms at work in the universe. They are crucial laboratories for understanding how galaxies form and evolve from early epochs until the present day. A key aspect of unlocking their fossil evidence is by

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A new low-dispersion objective-prism search for low-redshift (z

We present a search for Herschel-PACS counterparts of dust-obscured, high-redshift objects previously selected at submillimeter and millimeter wavelengths in the Great Observatories Origins Deep Survey North field. We detect 22 of 56 submillimeter galaxies (SMGs, 39%) with a signal-to-noise ratio of >=3 at 100 μm down to 3.0 mJy, and/or at 160 μm

(Hα+[NII])/[OIII] ratio images have been used to search for low-ionization small-scale structures in a sample of 258 planetary nebulae. Radially symmetrical knots or jet-like structures, which are enhanced in the ratio images compared to the neighbouring regions of the nebulae, have been identified in 23 objects. Some of these features are barely

The propagation of a shock wave into a medium is expected to heat the material beyond the shock, producing noticeable effects in intensity line ratios such as [O iii]/Hα. To investigate the occurrence of shocks in planetary nebulae (PNe), we have used all narrow-band [O iii] and Hα images of PNe available in the HST archive to build their [O iii]