【摘 要】
:
The age pattern across spiral arms is one of the key observational features utilised to study the dynamic nature of the Galaxy's spiral structure.With the most
【机 构】
:
Purple Mountain Observatory,Chinese Academy of Sciences,Nanjing 210023,China;University of Science a
论文部分内容阅读
The age pattern across spiral arms is one of the key observational features utilised to study the dynamic nature of the Galaxy's spiral structure.With the most updated samples of high-mass star formation region (HMSFR) masers,O stars and open clusters,we investigated their distributions and kinematic properties in the vicinity of the Sun.We found that the Sagittarius-Carina Arm traced by HMSFRs,O stars ((≤) 10 Myr) and young open clusters (<30 Myr) seem to deviate gradually towards the Galactic Anticenter (GAC) direction.The Local Arm traced by HMSFRs,O stars,young clusters and also medium-young clusters (30-100 Myr) are inclined to gradually deviate toward the Galactic Center (GC) direction.The properties for the Local Arm are supported by a simplified simulation of cluster motions in the Galaxy.Indications of systematic motions in the circular and radial velocities are noticed for the old open clusters(>200 Myr).These results are consistent with the idea that star formation can be triggered by spiral shocks of density waves,and indicate that the corotation radius of the Galaxy is located between the Sagittarius-Carina Arm and the Local Arm,close to the Solar circle.
其他文献
The LE is the low energy telescope that is carried on Insight-HXMT.It uses swept charge devices(SCDs) to detect soft X-ray photons.LE's time response is caused
Since Sep.2018,LAMOST has started the medium-resolution (R ~ 7500) spectral survey(MRS).We proposed the spectral survey of Galactic nebulae,including H Ⅱ region
美国能源信息署 (EIA) 近日表示,2012 年至 2020 年期间,美国的天然气地下储存能力基本持平,2019 年至 2020 年几乎没有变化.rn2019年,美国本土48州所有投产设施的设计容量或
SiO maser VLBA observations toward VX Sgr are performed at five epochs,and lots of maser spots are obtained.We make a statistical analysis on these spots.It is
Stars form through the gravitational collapse of molecular cloud cores.Before collapsing,the cores are supported by thermal pressure and turbulent motions.A que
High resolution imaging of inner jets in Active Galactic Nuclei (AGNs) with Very Long Baseline Interferometry (VLBI) at millimeter wavelengths provides deep ins
The conformity effect,indicating the evolution of galaxies is related to its surrounding neighbor galaxies as far as a few Mpc,is an interesting phenomenon in t
Synchrotron emission polarization is very sensitive to the magnetic field configuration.Recently,polarization of synchrotron emission with a mixed (SM) magnetic
In 21 cm intensity mapping,the spectral smoothness of the foreground is exploited to separate it from the much weaker 21 cm signal.However,the non-smooth freque
Dome A,Antarctica,has been thought to be one of the best astronomical sites on the Earth for decades.Since it was first visited by astronomers in 2008,dozens of