2018/10/29 by E. Zari, H. Hashemi, A. G. A. Brown +2 · 3 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics and Star Formation Studies #Cluster (spacecraft) #Extinction (optical mineralogy) #Gaussian #Hertzsprung–Russell diagram #Neighbourhood (mathematics) #Smoothing #Spatial distribution #Stars #Stellar, planetary, and galactic studies #astro-ph.GA #astro-ph.SR
paper · pdf · doi:10.1051/0004-6361/201834150
published as A&A 620, A172 (2018) · 17 pages, 17 figures, 6 appendixes; accepted for publication in A&A; image quality decreased to comply with the arXiv.org rules on file size
openalex created_date 2018/10/26 · openalex publication_date 2018/10/29 · arxiv created 2018/11/06 · arxiv updated 2018/12/19 · openalex updated_date 2026/08/05
We study the three dimensional arrangement of young stars in the solar neighbourhood using the second release of the Gaia mission ( Gaia DR2) and we provide a new, original view of the spatial configuration of the star-forming regions within 500 pc of the Sun. By smoothing the star distribution through a Gaussian filter, we construct three dimensional (3D) density maps for early-type stars (upper-main sequence, UMS) and pre-main sequence (PMS) sources. The PMS and the UMS samples are selected through a combination of photometric and astrometric criteria. A side product of the analysis is a 3D, G -band extinction map, which we use to correct our colour-magnitude diagram for extinction and reddening. Both density maps show three prominent structures, Scorpius-Centaurus, Orion, and Vela. The PMS map shows a plethora of lower-mass star-forming regions, such as Taurus, Perseus, Cepheus, Cassiopeia, and Lacerta, which are less visible in the UMS map due to the lack of large numbers of bright, early-type stars. We report the finding of a candidate new open cluster towards l , b ∼ 218.5° , − 2°, which could be related to the Orion star-forming complex. We estimate ages for the PMS sample and we study the distribution of PMS stars as a function of their age. We find that younger stars cluster in dense, compact clumps, and are surrounded by older sources, whose distribution is instead more diffuse. The youngest groups that we find are mainly located in Scorpius-Centaurus, Orion, Vela, and Taurus. Cepheus, Cassiopeia, and Lacerta are instead more evolved and less numerous. Finally, we find that the 3D density maps show no evidence for the existence of the ring-like structure which is usually referred to as the Gould Belt.