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Scientists conduct detailed diagnosis of mystery of famous diagonal ridge pattern in Milky Way
(Nanowerk News) Our solar neighborhood has many asymmetries, such as snail shape and ridge shape. Up to now, our astronomers are still lack of clear and enough information about the famous ridge structure.
Recently, a research team, led by LAMOST Fellow Dr. WANG Haifeng from the National Astronomical Observatories of Chinese Academy of Sciences (NAOC), collaborating with China and Spain astronomers, performed the detailed Chemo-Dynamical analysis of the diagonal ridge feature and presented a timing tagging for it with the help of LAMOST data.
The study was published in The Astrophysical Journal ("Diagonal Ridge Pattern of Different Age Populations Found in Gaia-DR2 with LAMOST Main-sequence Turnoff and OB-type Stars").
Researchers recovered the ridge pattern and found that this feature was presented from very young to very old stars. Meanwhile, some ridge features were also revealed in the chemical space.
"We found that there might be two kinds of ridge patterns with different dynamical origins and evolutions based on the statistical analysis," said Dr. WANG Haifeng, the first author of the study.
The viewpoint of the two kinds of origins is also supported by Prof. Joss Bland-Hawthorn, an astronomer from the University of Sydney of Australia.
"Some previous works pointed out clearly that the spiral arms in our home galaxy can generate ridges accompanied with the points that different ridges could have originated from different scenarios, but if they want to unify the global picture, the well-known Sagittarius satellite perturbation is favored," said Dr. Martín López-Corredoira, the co-author of this paper.
"In this work, we actually detect the similar signals as shown in some previous works," said Dr. WANG Haifeng.
"All these evidence might support that both the spiral arms or internal mechanism and Sgr perturbations or external mechanism are important contributors for this structure," said Dr. Martín López-Corredoira.
Referee of this paper pointed out that "These results provide additional constraints on the theoretical models, and encourage further theoretical studies to distinguish these scenarios based on the new observational constraints."
Source: Chinese Academy of Sciences