中文
相关论文

相关论文: The R1R2' outer ring revealed by young open cluste…

200 篇论文

The dark matter distribution of the Milky Way remains among the major unsolved problems about our home galaxy. The masses of other spiral galaxies can be determined from their rotation curves through long-slit spectroscopy. But for the…

天体物理学 · 物理学 2009-09-29 Peter M. Frinchaboy , Steven R. Majewski

We investigate the structure of our Galaxy's young stellar disc by fitting the distribution functions (DFs) of a new family to five-dimensional Gaia data for a sample of $47\,000$ OB stars. Tests of the fitting procedure show that the young…

星系天体物理 · 物理学 2022-07-20 Chengdong Li , James Binney

Models of the Galaxy with analytical Ferrers bars can reproduce the residual velocities of OB-associations in the Sagittarius, Perseus and Local System stellar-gas complexes located within 3 kpc solar neighborhood. Ferrers ellipsoids with…

星系天体物理 · 物理学 2019-02-12 Anna M. Melnik

Open star clusters from the MWSC (Milky Way Star Clusters) catalogue have been used to determine the Galactic rotation parameters. The circular rotation velocity of the solar neighborhood around the Galactic center has been found from data…

星系天体物理 · 物理学 2016-09-30 V. V. Bobylev , A. T. Bajkova , K. S. Shirokova

NGC 2355 is an old open cluster in the outer part of the galactic disk (l=203 deg, b=+11 deg) which has been little studied until now. This paper presents the first astrometric and spectroscopic investigation of this cluster. We have…

天体物理学 · 物理学 2007-05-23 C. Soubiran , M. Odenkirchen , J. -F. Le Campion

Velocity dispersion $\sigma$, radius $R$ and luminosity $L$ of elliptical galaxies are known to be related, leaving only two degrees of freedom and defining the so-called ``fundamental plane". In this {\em Letter} we present observational…

天体物理学 · 物理学 2016-06-08 R. Schaeffer , S. Maurogordato , A. Cappi , F. Bernardeau

The spatial distribution of known globular clusters (GCs) in the Milky Way shows that the current census of GCs is incomplete in the direction of the Galactic plane. We present the discovery of two new GCs located close to the Galactic…

星系天体物理 · 物理学 2018-08-29 Jinhyuk Ryu , Myung Gyoon Lee

A view of the Galactic bulge by means of their globular clusters is necessary for a deep understanding of its formation and evolution. Connections between the globular cluster and field star properties in terms of kinematics, orbits,…

太阳与恒星天体物理 · 物理学 2016-07-06 E. Bica , S. Ortolani , B. Barbuy

We report a discovery of an extended globular-like star cluster, M33-EC1, at the outer edge of the spiral galaxy M33. The distance to the cluster is 890 kpc, and it lies at a 12.5 kpc projected distance from the center of M33. Old age (>~7…

We present the analysis of a local (z = 0.04 - 0.2) sample of 31 galaxy clusters with the aim of measuring the density of the X-ray emitting gas in cluster outskirts. We compare our results with numerical simulations to set constraints on…

宇宙学与河外天体物理 · 物理学 2015-10-08 D. Eckert , F. Vazza , S. Ettori , S. Molendi , D. Nagai , E. T. Lau , M. Roncarelli , M. Rossetti , S. L. Snowden , F. Gastaldello

We analyzed the shapes of Galactic open clusters by the star counting technique with the 2MASS star catalog database. Morphological parameters such as the ellipticity and size have been derived via stellar density distribution, weighed by…

天体物理学 · 物理学 2009-11-10 W. P. Chen , C. W. Chen , C. G. Shu

We have shown previously (Bobylev et al 2011) that some of the stars in the Solar neighborhood today may have originated in the same star cluster as the Sun, and could thus be called Solar Siblings. In this work we investigate the…

星系天体物理 · 物理学 2015-01-22 M. Valtonen , A. T. Bajkova , V. V. Bobylev , A. Myllari

We present a newly-developed, three-dimensional spatial classification method, designed to analyze the spatial distribution of early type stars within the 1 kpc sphere around the Sun. We propose a distribution model formed by two…

天体物理学 · 物理学 2008-11-26 F. Elias , J. Cabrera-Cano , E. J. Alfaro

Globular clusters in the outer halo (R_gc > 15 kpc) are found to be systematically fainter than those at smaller Galactocentric distances. Within the outer halo the compact clusters with half-light radii R_h < 10 pc are only found at R_gc <…

天体物理学 · 物理学 2009-09-17 Sidney van den Bergh , Dougal Mackey

The young open star cluster M25 (IC 4725) is located in the direction of the galactic center in a crowded region, near much irregular absorption features on Sagittarius arm. This cluster has some difficult observing problems due to its…

天体物理学 · 物理学 2007-05-23 A. L. Tadross , A. I. Osman , M. A. Marie , S. M. Hassan , .

We present a new supergiant-rich stellar cluster hidden by extinction and christen it as Barb\'a 2, in honor of its discoverer Rodolfo Barb\'a. The cluster is at a distance of $7.39^{+0.65}_{-0.55}$ kpc and contains several supergiants, of…

星系天体物理 · 物理学 2024-10-04 J. Maíz Apellániz , I. Negueruela

We discuss our current progress in studying a sample of z>0.8 clusters of galaxies from the ROSAT Distant Cluster Survey. To date, we have Chandra observations for four of the ten clusters. We find that the morphology of two of these four…

天体物理学 · 物理学 2007-05-23 B. Holden , S. A. Stanford , P. Rosati , P. Tozzi , G. Squires , S. Borgani , P. Eisenhardt

We perform a systematic reanalysis of the age distribution of Galactic open star clusters. Using a catalogue of homogeneously determined ages for 834 open clusters contained in a 2 kpc cylinder around the Sun and characterised with…

We present a detailed analysis of the surface brightness distribution of the brightest cluster galaxy (BCG) in each of 24 galaxy clusters at 0.03<z<0.13. We use two-dimensional profile fitting to model the surface brightness out to r=300…

天体物理学 · 物理学 2014-10-13 Anthony H. Gonzalez , Ann I. Zabludoff , Dennis Zaritsky

By using the ARRAKIS, the atlas of stellar rings in galaxies (Comeron et al. 2014) based on data of the S4G survey, we have compiled a list of early-type, S0-Sb, disk galaxies with outer stellar ring-like features (`pure' rings, R, or…

星系天体物理 · 物理学 2018-03-14 I. P. Kostiuk , O. K. Sil'chenko