20,635 research outputs found
The IACOB project: A grid-based automatic tool for the quantitative spectroscopic analysis of O-stars
We present the IACOB grid-based automatic tool for the quantitative
spectroscopic analysis of O-stars. The tool consists of an extensive grid of
FASTWIND models, and a variety of programs implemented in IDL to handle the
observations, perform the automatic analysis, and visualize the results. The
tool provides a fast and objective way to determine the stellar parameters and
the associated uncertainties of large samples of O-type stars within a
reasonable computational time.Comment: 8 pages, 2 figures, 1 table. Proceedings of the "GREAT-ESF Stellar
Atmospheres in the Gaia Era Workshop
Economic Inequality in Spain: The European Union Household Panel Dataset
This article uses data from the 1998 European Union Household Panel to study economic inequality in Spain. It reports data on the Spanish distributions of income, labor income, and capital income, and on related features of inequality, such as age, employment status, educational attainment, and marital status. It also reports data on the income mobility of Spanish households.
We find that income, earnings, and, very especially, capital income are very unequally distributed in Spain
The IACOB project: I. Rotational velocities in Northern Galactic O and early B-type stars revisited. The impact of other sources of line-broadening
Stellar rotation is an important parameter in the evolution of massive stars.
Accurate and reliable measurements of projected rotational velocities in large
samples of OB stars are crucial to confront the predictions of stellar
evolutionary models with observational constraints. We reassess previous
determinations of projected rotational velocities (vsini) in Galactic OB stars
using a large, high quality spectroscopic dataset, and a strategy which account
for other sources of broadening appart from rotation affecting the diagnostic
lines We present a versatile and user friendly IDL tool, based on a combined
Fourier Transform (FT) + goodness of fit (GOF) methodology, for the
line-broadening characterization in OB-type stars. We use this tool to (a)
investigate the impact of macroturbulent and microturbulent broadenings on
vsini measurements, and (b) determine vsini in a sample of 200 Galactic OB-type
stars, also characterizing the amount of macroturbulent broadening (\vmacro)
affecting the line profiles. We present observational evidence illustrating the
strengths and limitations of the proposed FT+GOF methodology for the case of OB
stars. We confirm previous statements (based on indirect arguments or smaller
samples) that the macroturbulent broadening is ubiquitous in the massive star
domain. We compare the newly derived vsini with previous determinations not
accounting for this extra line-broadening contribution, and show that those
cases with vsini< 120 km/s need to be systematically revised downwards by ~25
(+/-20) km/s. We suggest that microturbulence may impose an upper limit below
which vsini and \vmacro\ could be incorrectly derived by means of the proposed
methodology as presently used, and discuss the implications of this statement
on the study of relatively narrow line massive stars.Comment: Accepted for publication in A&A (19 pages, 15 figures, 6 tables).
Tables A1-A5 will be make available in the final edited version of the paper
(or under request to SS-D
Dynamical coupled-channels: the key to understanding resonances
Recent developments on a dynamical coupled-channels model of hadronic and
electromagnetic production of nucleon resonances are summarized.Comment: Invited Plenary talk at the 20th European Conference on Few-Body
Problems in Physics (EFB20), September 10-14 2007, Pisa, Italy. To appear in
the proceedings in Few-Body System
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