Asteroseismology of Solar-type Stars with Kepler I: Data Analysis

We report on the first asteroseismic analysis of solar-type stars observed by Kepler. Observations of three G-type stars, made at one-minute cadence during the first 33.5d of science operations, reveal high signal-to-noise solar-like oscillation spectra in all three stars: About 20 modes of oscillation can clearly be distinguished in each star. We discuss the appearance of the oscillation spectra, including the presence of a possible signature of faculae, and the presence of mixed modes in one of the three stars.Comment: 5 pages, 4 figure, submitted to Astronomische Nachrichte

Chiral dynamics of baryon resonances and hadrons in a nuclear medium

In these lectures I make an introduction to chiral unitary theory applied to the meson baryon interaction and show how several well known resonances are dynamically generated, and others are predicted. Two very recent experiments are analyzed, one of them showing the existence of two $\Lambda(1405)$ states and the other one providing support for the $\Lambda(1520)$ resonance as a quasibound state of $\Sigma(1385) \pi$. The use of chiral Lagrangians to account for the hadronic interaction at the elementary level introduces a new approach to deal with the modification of meson and baryon properties in a nuclear medium. Examples of it for $\bar{K}$, $\eta$ and $\phi$ modification in the nuclear medium are presented.Comment: Lectures given in the Workshop on Hadron Physics, Puri (India), march 200

Dynamically generated resonances from the vector octet-baryon decuplet interaction

We study the interaction of the octet of vector mesons with the decuplet of baryons using Lagrangians of the hidden gauge theory for vector interactions. The unitary amplitudes in coupled channels develop poles that can be associated with some known baryonic resonances, while there are predictions for new ones at the energy frontier of the experimental research. The work offers guidelines on how to search for these resonances

Scalar mesons moving in a finite volume and the role of partial wave mixing

Phase shifts and resonance parameters can be obtained from finite-volume lattice spectra for interacting pairs of particles, moving with nonzero total momentum. We present a simple derivation of the method that is subsequently applied to obtain the pi pi and pi K phase shifts in the sectors with total isospin I=0 and I=1/2, respectively. Considering different total momenta, one obtains extra data points for a given volume that allow for a very efficient extraction of the resonance parameters in the infinite-volume limit. Corrections due to the mixing of partial waves are provided. We expect that our results will help to optimize the strategies in lattice simulations, which aim at an accurate determination of the scattering and resonance properties.Comment: 19 pages, 12 figure

Resonances in chiral unitary approaches

The extension of chiral theories to the description of resonances, via the incorporation of unitarity in coupled channels, has provided us with a new theoretical perspective on the nature of some of the observed excited hadrons. In this contribution some of the early achievements in the field of baryonic resonances are reviewed, the recent evidence of the two-pole nature of the Lambda(1405) is discussed and results on charmed baryon resonances are presented.Comment: 6 pages, contribution to the Workshop on the Physics of excited nucleons (NSTAR 2007), Bonn (Germany) 5-8 September 200

f(1)(1285) decays into a(0)(980) pi(0), f(0)(980) pi(0) and isospin breaking

We evaluate the decay width for the processes f1(1285). p 0 a0(980) and f1(1285). p 0 f0(980) taking into account that all three resonances are dynamically generated from the meson- meson interaction, the f1(1285) from K* K ¿ c. c. and the a0(980), f0(980) from p., K K and pp, K _ K, respectively. We use a triangular mechanism similar to that of.(1405). pp., which provides a decay width for f1(1285). p 0 a0(980) with a branching fraction of the order of 30%, in agreement with experiment. At the same time we evaluate the decay width for the isospin- forbidden f1(1285). p 0 f0(980), which appears when we consider different masses for the charged and neutral kaons, and show that it is much more suppressed than in the.(1405). pp. case, but gives rise to a narrow shape of the p + p- distribution similar to the one found in the eta(1405) -> pi pi eta decay

CryoSat instrument performance and ice product quality status

Over the past 20 years, satellite radar altimetry has shown its ability to revolutionise our understanding of the ocean and climate. Previously, these advances were largely limited to ice-free regions, neglecting large portions of the Polar Regions. Launched in 2010, the European Space Agency’s (ESA) polar-orbiting CryoSat satellite was specifically designed to measure changes in the thickness of polar sea ice and the elevation of the ice sheets and mountain glaciers. To reach this goal, the CryoSat products have to meet the highest performance standards, achieved through continual improvements of the associated Instrument Processing Facilities. Since April 2015, the CryoSat ice products are generated with Baseline-C, which represented a major processor upgrade. Several improvements were implemented in this new Baseline, most notably the release of freeboard data within the Level 2 products. The Baseline-C upgrade has brought significant improvements to the quality of Level-1B and Level-2 products relative to the previous Baseline-B products, which in turn is expected to have a positive impact on the scientific exploitation of CryoSat measurements over land ice and sea ice. This paper provides an overview of the CryoSat ice data quality assessment and evolutions, covering all quality control and calibration activities performed by ESA and its partners. Also discussed are the forthcoming evolutions of the processing chains and improvements anticipated in the next processing Baseline

Comprehensive Comparison of Various Techniques for the Analysis of Elemental Distributions in Thin Films

The present work shows results on elemental distribution analyses in Cu(In,Ga)Se2 thin films for solar cells performed by use of wavelength-dispersive and energy-dispersive X-ray spectrometry (EDX) in a scanning electron microscope, EDX in a transmission electron microscope, X-ray photoelectron, angle-dependent soft X-ray emission, secondary ion-mass (SIMS), time-of-flight SIMS, sputtered neutral mass, glow-discharge optical emission and glow-discharge mass, Auger electron, and Rutherford backscattering spectrometry, by use of scanning Auger electron microscopy, Raman depth profiling, and Raman mapping, as well as by use of elastic recoil detection analysis, grazing-incidence X-ray and electron backscatter diffraction, and grazing-incidence X-ray fluorescence analysis. The Cu(In,Ga)Se2 thin films used for the present comparison were produced during the same identical deposition run and exhibit thicknesses of about 2 μm. The analysis techniques were compared with respect to their spatial and depth resolutions, measuring speeds, availabilities, and detection limit