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Baade's window and APOGEE : Metallicities, ages, and chemical abundances

Context. Baade's window (BW) is one of the most observed Galactic bulge fields in terms of chemical abundances. Owing to its low and homogeneous interstellar absorption it is considered the perfect calibration field for Galactic bulge studies. Aims. In the era of large spectroscopic surveys, calibration fields such as BW are necessary for cross calibrating the stellar parameters and individual abu

Chemical Abundances of M-Dwarfs from the Apogee Survey. I. the Exoplanet Hosting Stars Kepler-138 and Kepler-186

We report the first detailed chemical abundance analysis of the exoplanet-hosting M-dwarf stars Kepler-138 and Kepler-186 from the analysis of high-resolution (R ∼ 22,500) H-band spectra from the SDSS-IV-APOGEE survey. Chemical abundances of 13 elements - C, O, Na, Mg, Al, Si, K, Ca, Ti, V, Cr, Mn, and Fe - are extracted from the APOGEE spectra of these early M-dwarfs via spectrum syntheses compu

Activity and participation long term after stroke

Background and aim: As an increasing number of people are living and ageing with the consequences ofstroke, the rehabilitation and support provided for this group needs to have a long-term perspective. Moreover,to prevent long-term activity limitations and participation restrictions after stroke, increased knowledge is neededregarding how engagement in different types of activities develops beyond

Sloan Digital Sky Survey IV : Mapping the Milky Way, Nearby Galaxies, and the Distant Universe

We describe the Sloan Digital Sky Survey IV (SDSS-IV), a project encompassing three major spectroscopic programs. The Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) is observing hundreds of thousands of Milky Way stars at high resolution and high signal-to-noise ratios in the near-infrared. The Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey is obtaining spa

Chiral perturbation theory in the meson sector

The present status of Chiral Perturbation Theory in the meson sector is discussed concentrating on recent developments. This write-up contains short discussions on a listing of a few historical papers, the principles behind ChPT, two-flavour ChPT including some comments about the Pion polarizability, three-flavour ChPT with a discussion of the recently found relations as tests of ChPT and prelimin

Baryon weak decays

A short overview of baryon weak decays and our present theoretical understanding is given. The successes and shortcomings of the various approaches are compared.

Progress in K → ππ decays

Recent work by J. Prades and myself on K → ππ is described. The first part describes our method to connect in a systematic fashion the short-distance evolution with long-distance matrix-element calculations taking the scheme dependence of the short-distance evolution into account correctly. In the second part I show the results we obtain for the ΔI = 1/2 rule in the chiral limit.

Chiral Lagrangians and Nambu-Jona-Lasinio like models

We discuss the low-energy analysis of models involving quarks and four-fermion couplings. The relation with QCD and with other models of mesons and meson plus quarks at low energies is discussed. A short description of how the heat-kernel expansion can be used to get regularization independent information, is given. The anomaly within this class of models and a physical prescription to obtain the

The anomalous sector of the strong interaction effective lagrangian

The effective action in the abnormal intrinsic parity sector is derived to next-to-leading order in the chiral perturbation theory expansion in the chiral limit under the assumption that chiral symmetry breaking is well described by the addition of a constituent quark mass term to the QCD action. The result is combined with the loop calculation done previously for the case of pseudoscalar decays i

Violations of Dashen's theorem

The electromagnetic contribution to the K+-K0 mass difference is calculated in the 1 Nc approach including the SU(3) breaking contributions due to a non-zero strange quark mass. The short-distance contribution can be unambiguously determined in terms of the known parameters of the next-to-leading order chiral Lagrangian. The long distance part is estimated using the 1 Nc approach by Bardeen et al.

Kℓ4 decays and the low-energy expansion

Tha amplitudes for the Kℓ4 decays are calculated to next-to-leading order in Chiral Perturbation Theory. These are then compared with the available experimental results on these decays. The values of the parameters L1, 2, 3 previously determined from ππ scattering are compared with those obtained here. A short overview of the determination of the parameters of Chiral Perturbation Theory is include

On the validity of chiral perturbation theory for the ΔI= 1 2 rule

The chiral perturbation theory relations of 〈ππ|O|K〉 to 〈π|O|K〉 and 〈o|O|K〉 needed for establishing the ΔI= 1 2 rule in hadronic weak decays via lattice calculations are examined beyond leading order and the domain of validity for this relation is established.

ε′KK in the chiral limit

The K → ππ system is analyzed in the chiral limit within the Standard Model. We discuss how to connect the short-distance running in the |ΔS| = 1 case to the matrix-elements calculated in a low-energy approximation in a scheme-independent fashion. We calculate this correction and the resulting Wilson Coefficients. The matrix elements are calculated to next-to-leading order in the 1/Nc expansion an