| Issue |
EAS Publications Series
Volume 67-68, 2014
The Milky Way Unravelled by Gaia: GREAT Science from the Gaia Data Releases
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|---|---|---|
| Page(s) | 205 - 209 | |
| Section | The Origin and History of the Milky Way | |
| DOI | https://doi.org/10.1051/eas/1567037 | |
| Published online | 17 July 2015 | |
N.A. Walton, F. Figueras, L. Balaguer-Núñez and C. Soubiran (eds)
EAS Publications Series, 67–68 (2014) 205-209
The Perseus arm stellar overdensity at 1.6 kpc
1 Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal. Escuela Politécnica Superior, Universidad de Alicante, Apdo. 99, 03080 Alicante, Spain
2 European Southern Observatory, Karl-Schwarzschild-Str. 2, 85748 Garching, Germany
3 Departament d'Astronomia i Meteorologia and IEEC-ICC-UB, Universitat de Barcelona, Martí i Franquès, 1, 08028 Barcelona, Spain
The stellar overdensity due to the Perseus arm has been detected in the anticenter direction through individual field stars. For that purpose, a Strömgren photometric survey covering 16∘2 was developed with the Wide Field Camera at the Isaac Newton Telescope. This photometry allowed us to compute individual physical parameters for these stars using a new method based on atmospheric models and evolutionary tracks. The analysis of the surface density as a function of distance for intermediate young stars in this survey allowed us to detect an overdensity at 1.6 ± 0.2 kpc from the Sun, that can be associated with the Perseus arm, with a surface density amplitude of ∼14%. The significance of the detection is above 4σ for all the cases. The fit for the radial scale length of the Galactic disk provided values in the range [2.9,3.5] kpc for the population of the B4-A1 stars. We also analyzed the interstellar visual absorption distribution, and its variation as a function of distance is coherent with a dust layer before the Perseus arm location.
© EAS, EDP Sciences, 2015