We study two δ Scuti stars, V830 Her and HD 163032, using four-year asteroseismic photometric data taken with the Taiwan Automated Telescope Network. We check the consistency of the pulsational frequencies obtained from data of different years and sites with three different methods to remove the artificial frequencies. Fourteen frequencies are

We present initial abundance gradients in the Milky Way as determined from high-resolution (R > 20,000) spectra of red giant stars. Our observations were taken with the SDSS-III APO Galactic Evolution Experiment (APOGEE) and have a S/N of at least 100. APOGEE is able to sample a large range of Galactocentric radii (RGC) including the bulge and

To determine the spectral type, the rotational velocity and the radial velocity amplitude of the primary, we obtained 46 high-resolution (R~85000) echelle spectra using the HERMES spectrograph at the 1.2-m Mercator telescope (La Palma, Canary Islands). These were reduced using the standard instrument-specific data reduction pipeline. Additionally

Single junction In0.52Al0.48As solar cells have been grown on a (100) GaAs substrate by employing a 1 μm thick compositionally graded InxGa1-xAs/InP metamorphic buffer layer to accommodate the 3.9% mismatch. Cells processed from the 0.8 μm thick InAlAs layers had photovoltaic conversion efficiency of 5% with an open circuit voltage of 0.72 V, short

We present a list of 13 candidate gravitationally lensed submillimeter galaxies (SMGs) from 95 deg2 of the Herschel Multi-tiered Extragalactic Survey, a surface density of 0.14 ± 0.04 deg–2. The selected sources have 500 μm flux densities (S 500) greater than 100 mJy. Gravitational lensing is confirmed by follow-up observations in 9 of the 13

Context. The nature of ultra-luminous X-ray (ULX) sources is still a matter of debate. Studies of their counterparts in other spectral ranges will help to clarify the nature of those sources. Aims: Our goal was to identify and characterize the optical counterparts of five sources catalogued as ULXs. Methods: We obtained optical imaging and