This paper is the first in a set that analyses the covariance matrices of clustering statistics obtained from several approximate methods for gravitational structure formation. We focus here on the covariance matrices of anisotropic two-point correlation function measurements. Our comparison includes seven approximate methods, which can be divided

This paper represents the conclusion of a project that had two main goals: (1) to investigate to what extent planetary nebulae (PNe) are chemically homogeneous; and (2) to provide physical constraints on the central star properties of each PN. We accomplished the first goal by using HST/STIS spectra to measure the abundances of seven elements in

The large amount of chemical and kinematic information available in large spectroscopic surveys has inspired the search for chemically peculiar stars in the field. Though these metal-poor field stars ([Fe/H]

Aims: The main goal of this work is to measure rotation periods of the M-type dwarf stars being observed by the CARMENES exoplanet survey to help distinguish radial-velocity signals produced by magnetic activity from those produced by exoplanets. Rotation periods are also fundamental for a detailed study of the relation between activity and

To date, the SDSS-IV APOGEE survey has obtained S/N > 70 spectra for over 2,500 red giant stars distributed across much of the Large Magellanic Cloud (LMC), allowing for the characterization of the detailed abundance patterns for 10+ chemical elements. In this project, we interpret the chemical abundance patterns of the LMC by comparing them to the

We present the results of CO interferometric observations of the southern elliptical galaxy NGC 3557 with ALMA. We have detected both the CO(1–0) emission line and a relatively strong continuum at 3 mm. The continuum shows a flat-spectrum central unresolved source (at our angular resolution of 0.″7) and two jets, associated with the larger-scale