Simulations of the Hyades

Abstract

Context: Using the recent observational data of Röser et al. we present $N$-body simulations of the Hyades open cluster. Aims: We make an attempt to determine initial conditions of the Hyades cluster at the time of its formation in order to reproduce the present-day cumulative mass profile, stellar mass and luminosity function (LF). Methods: We performed direct $N$-body simulations of the Hyades in an analytic Milky Way potential that account for stellar evolution and include primordial binaries in a few models. Furthermore, we applied a Kroupa (2001) IMF and used extensive ensemble-averaging. Results: We find that evolved single-star King initial models with King parameters $W_0=6-9$ and initial particle numbers $N_0=3000$ provide good fits to the observational present-day cumulative mass profile within the Jacobi radius. The best-fit King model has an initial mass of $1721M_{\odot }$ and an average mass loss rate of $-2.2M_{\odot }/\mathrm{Myr}$. The K-band LFs of models and observations show a reasonable agreement. Mass segregation is detected in both observations and models. If 33% primordial binaries are included the initial particle number is reduced by 5% as compared to the model without primordial binaries. Conclusions: The present-day properties of the Hyades can be well reproduced by a standard King or Plummer initial model when choosing appropriate initial conditions. The degeneracy of good-fitting models can be quite high due to the large dimension of the parameter space. More simulations with different Roche-lobe filling factors and primordial binary fractions are required to explore this degeneracy in more detail.

14 pages, 16+1 figures, hopefully final version, contains a note added in proof

References in corpus (26)

• On the variation of the Initial Mass Function
• Local Kinematics and the Local Standard of Rest
• The Initial Mass Function of Stars: Evidence for Uniformity in Variable Systems
• Comprehensive analytic formulae for stellar evolution as a function of mass and metallicity
• The Dartmouth Stellar Evolution Database
• The PPMXL catalog of positions and proper motions on the ICRS. Combining USNO-B1.0 and 2MASS
• Parallaxes and proper motions for 20 open clusters as based on the new Hipparcos catalogue
• Star cluster ecology IVa: Dissection of an open star cluster---photometry
• The Third US Naval Observatory CCD Astrograph Catalog (UCAC3)
• A Family of Models for Spherical Stellar Systems
• Revisiting the population of Galactic open clusters
• On the galactic disc age-metallicity relation
• Direct N-body Modelling of Stellar Populations: Blue Stragglers in M67
• A class of symplectic integrators with adaptive timestep for separable Hamiltonian systems
• A deep all-sky census of the Hyades
• Star Clusters with Primordial Binaries: I. Dynamical Evolution of Isolated Models
• The fraction of binary systems in the core of five Galactic open clusters
• The White Dwarf Deficit in Open Clusters: Dynamical Processes
• The Distances to Open Clusters from Main-Sequence Fitting. I. New Models and a Comparison to the Properties of the Hyades Eclipsing Binary vB 22
• Large scale inhomogeneity and local dynamical friction
• A highly efficient measure of mass segregation in star clusters
• A new method to create initially mass segregated star clusters in virial equilibrium
• Hyades dynamics from N-body simulations: Accuracy of astrometric radial velocities from Hipparcos
• On the dissolution of star clusters in the Galactic centre. I. Circular orbits
• New white dwarfs in the Hyades --Results from kinematic and photometric studies
• Calibration of radii and masses of open clusters with a simulation

Cited by in corpus (31)

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• The Hyades tidal tails revealed by Gaia DR2
• Extended stellar systems in the solar neighborhood -- V. Discovery of coronae of nearby star clusters
• Extended stellar systems in the solar neighborhood - I. The tidal tails of the Hyades
• Untangling the Galaxy. II. Structure within 3 kpc
• Extended stellar systems in the solar neighborhood - II. Discovery of a nearby 120° stellar stream in Gaia DR2
• Discovery of Tidal Tails in Disrupting Open Clusters: Coma Berenices and a Neighbor Stellar Group
• Praesepe (NGC 2632) and its tidal tails
• Asymmetrical tidal tails of open star clusters: stars crossing their cluster's prah challenge Newtonian gravitation
• The fate of planetesimal discs in young open clusters: implications for 1I/'Oumuamua, the Kuiper belt, the Oort cloud and more
• Towards a complete stellar mass function of the Hyades. I. Pan-STARRS1 optical observations of the low-mass stellar content
• The Hyades Cluster: Identification of a Planetary System and Escaping White Dwarfs
• Cosmological Insights into the Early Accretion of \textit{r}-Process-Enhanced stars. I. A Comprehensive Chemo-dynamical Analysis of LAMOST J1109+0754
• Detectability of Free Floating Planets in Open Clusters with JWST
• Kinematic modelling of clusters with Gaia: the Death Throes of the Hyades
• Extended Tidal Tails of IC 4756 detected by {\it Gaia} EDR3
• A flexible method to evolve collisional systems and their tidal debris in external potentials
• Roche volume filling and the dissolution of open star clusters
• Collinder 135 and UBC 7: A Physical Pair of Open Clusters
• Spectroscopic and photometric studies of white dwarfs in the Hyades
• Mass Segregation in the Hyades Cluster
• Simulating Star Clusters with the AMUSE Software Framework: I. Dependence of Cluster Lifetimes on Model Assumptions and Cluster Dissolution Modes
• Dynamical evolution of Milky Way globular clusters on the cosmological timescale I. Mass loss and interaction with the nuclear star cluster
• Unraveling UBC 274: a morphological, kinematical and chemical analysis of a disrupting open cluster
• A study of the frequency and characteristics of stellar companions and Jupiter-like planets in nearby open clusters
• Evolution of the disky second generation of stars in globular clusters on cosmological timescale
• The 800pc long tidal tails of the Hyades star cluster: Possible discovery of candidate epicyclic overdensities from an open star cluster
• Cosmological insights into the early accretion of r-process-enhanced stars II. Dynamical identification of lost members of Reticulum II
• A survey for low-mass stellar and substellar members of the Hyades open cluster
• Dynamical model of Praesepe and its tidal tails
• The contribution to Galactic Centre γ-ray excess from cluster-born millisecond pulsars. Constraints from direct N-body simulations