Extended stellar systems in the solar neighborhood

Meingast, Stefan; Alves, J.; Rottensteiner, Alena

doi:10.1051/0004-6361/202038610

Cited by 112 publications

(142 citation statements)

References 125 publications

Supporting

Mentioning

122

Contrasting

Order By: Relevance

“…It is less clear what the dissolution timescale is of their local kinematic substructure, which represents a ‘memory’ of the formation environment. Many unbound co-moving groups, that are correlated both spatially and kinematically, occupy the solar neighbourhood 41 – 43 . Such groups may be composed of stars that are co-natal 44 , or may be the result of resonant perturbation due to the galactic potential 19 , 20 , 45 , 46 .…”

Section: Methodsmentioning

confidence: 99%

Stellar clustering shapes the architecture of planetary systems

Winter

Kruijssen

Longmore

et al. 2020

Nature

109

View full text Add to dashboard Cite

Planet formation is generally described in terms of a system containing the host star and a protoplanetary disk 1 – 3 , of which the internal properties (for example, mass and metallicity) determine the properties of the resulting planetary system 4 . However, (proto)planetary systems are predicted 5 , 6 and observed 7 , 8 to be affected by the spatially clustered stellar formation environment, through either dynamical star–star interactions or external photoevaporation by nearby massive stars 9 . It is challenging to quantify how the architecture of planetary sysems is affected by these environmental processes, because stellar groups spatially disperse within less than a billion years 10 , well below the ages of most known exoplanets. Here we identify old, co-moving stellar groups around exoplanet host stars in the astrometric data from the Gaia satellite 11 , 12 and demonstrate that the architecture of planetary systems exhibits a strong dependence on local stellar clustering in position-velocity phase space. After controlling for host stellar age, mass, metallicity and distance from the star, we obtain highly significant differences (with p values of 10 −5 to 10 −2 ) in planetary system properties between phase space overdensities (composed of a greater number of co-moving stars than unstructured space) and the field. The median semi-major axis and orbital period of planets in phase space overdensities are 0.087 astronomical units and 9.6 days, respectively, compared to 0.81 astronomical units and 154 days, respectively, for planets around field stars. ‘Hot Jupiters’ (massive, short-period exoplanets) predominantly exist in stellar phase space overdensities, strongly suggesting that their extreme orbits originate from environmental perturbations rather than internal migration 13 , 14 or planet–planet scattering 15 , 16 . Our findings reveal that stellar clustering is a key factor setting the architectures of planetary systems.

show abstract

Section: Methodsmentioning

confidence: 99%

Stellar clustering shapes the architecture of planetary systems

Winter

Kruijssen

Longmore

et al. 2020

Nature

109

View full text Add to dashboard Cite

show abstract

“…A Galaxy-wide survey using the Gaia DR2 catalogue reveals many elongated structures made of coeval stars, many of which are tidal tails of dissolving star clusters (Kounkel & Covey 2019). Meingast et al (2021) described the nearby extended spatial distribution of stars that co-move with their clusters but are not bound to them. After the release of the Gaia DR2 catalogue, tidal tails have been found around four nearby (<300 pc) OCs, namely Blanco 1 (≈100 Myr, Zhang et al 2020), the Hyades (≈600−700 Myr; Douglas et al 2019;Gossage et al 2018;Reino et al 2018;Lodieu 2020;Gaia Collaboration 2018b), Coma Berenices (≈750 Myr; Tang et al 2019;Fürnkranz et al 2019), and Praesepe (≈800 Myr; .…”

Section: Introductionmentioning

confidence: 99%

The 800 pc long tidal tails of the Hyades star cluster

Jeřabková

Boffin

Beccari

et al. 2021

A&A

View full text Add to dashboard Cite

The tidal tails of stellar clusters provide an important tool for studying the birth conditions of the clusters and their evolution, coupling, and interaction with the Galactic potential. The Gaia satellite, with its high-quality astrometric data, opened this field of study, allowing us to observe large-scale tidal tails. Theoretical models of tidal-tail formation and evolution are available. However, the exact appearance of tidal features as seen in the Gaia catalogue has not yet been studied. Here we present the N-body evolution of a Hyades-like stellar cluster with backward-integrated initial conditions on a realistic 3D orbit in the Milky Way galaxy computed within the AMUSE framework. For the first time, we explore the effect of the initial cluster rotation and the presence of lumps in the Galactic potential on the formation and evolution of tidal tails. For all of our simulations we present Gaia observables and derived parameters in the convergent point (CP) diagram. We show that the tidal tails are not naturally clustered in any coordinate system and that they can span up to 40 km s−1 relative to the cluster centre in proper motions for a cluster age of 600–700 Myr. Models with initial rotation result in significant differences in the cluster mass loss and follow different angular momentum time evolution. Thus the orientation of the tidal tails relative to the motion vector of the cluster and the current cluster angular momentum constrain the initial rotation of the cluster. We highlight the use of the standard CP method in searches for co-moving groups and introduce a new compact CP (CCP) method that accounts for internal kinematics based on an assumed model. Using the CCP method, we are able to recover candidate members of the Hyades tidal tails in the Gaia Data Release 2 and early Data Release 3 (eDR3) reaching a total extent of almost 1 kpc. We confirm the previously noted asymmetry in the detected tidal tails. In the eDR3 data we recovered spatial overdensities in the leading and trailing tails that are kinematically consistent with being epicyclic overdensities and thus would present candidates for the first such detection in an open star cluster. We show that the epicyclic overdensities are able to provide constraints not only on the cluster properties, but also on the Galactic potential. Finally, based on N-body simulations, a close encounter with a massive Galactic lump can explain the observed asymmetry in the tidal tails of the Hyades.

show abstract

“…We took as the basis for our cluster sample the x-y maps from Meingast et al (2021) (their figure A.2). In addition to these structures, which still surround gravitationally bound clusters, we include two tidal streams into our sample: the Psc-Eri stream from Meingast et al (2019) with an age determination of Curtis et al (2019), and the µ Tauri association from Gagné et al (2020).…”

Section: Age Determinationmentioning

confidence: 99%

“…Requiring the ratio between the mean and standard deviation as nseg /σn seg 2, we obtain nseg 4. Further assuming that each tidal tail contains typically at least 300 stars (Meingast et al 2021, their fig. 12), one obtains kseg = 300/ nseg = 75 azimuthal segments, i.e.…”

Section: Age Determinationmentioning

confidence: 99%

“…The remnant of the star cluster which survives this event is accompanied by these stars. The existence of the extended stellar structures was predicted theoretically from the results of N-body simulations (Kroupa et al 2001), and further explored by Dinnbier & Kroupa (2020a), before similar structures surrounding star clusters were observed (Meingast et al 2021) thanks to the unprecedented sensitivity of the Gaia mission (Gaia Collaboration et al 2016. At least some of these structures are coeval with the star cluster (Bouma et al 2021), which supports the view of their common origin.…”

Section: Introductionmentioning

confidence: 98%

See 1 more Smart Citation

Estimating the ages of open star clusters from properties of their extended tidal tails

Dinnbier,

Kroupa,

Šubr

et al. 2021

Preprint

View full text Add to dashboard Cite

The most accurate current methods for determining the ages of open star clusters, stellar associations and stellar streams are based on isochrone fitting or the lithium depletion boundary. We propose another method for dating these objects based on the morphology of their extended tidal tails, which have been recently discovered around several open star clusters. Assuming that the early-appearing tidal tails, the so called tidal tails I, originate from the stars released from the cluster during early gas expulsion, or that they form in the same star forming region as the cluster (i.e. being coeval with the cluster), we derive the analytical formula for the tilt angle β between the long axis of the tidal tail and the orbital direction for clusters or streams on circular trajectories. Since at a given Galactocentric radius, β is only a function of age t regardless of the initial properties of the cluster, we estimate the cluster age by inverting the analytical formula β = β(t). We illustrate the method on a sample of 12 objects, which we compiled from the literature, and we find a reasonable agreement with previous dating methods in ≈ 70% of the cases. This can probably be improved by taking into account the eccentricity of the orbits and by revisiting the dating methods based on stellar evolution. The proposed morphological method is suitable for relatively young clusters (age 300 Myr), where it provides a relative age error of the order of 10 to 20% for an error in the observed tilt angle of 5 • .

show abstract

Extended stellar systems in the solar neighborhood

Abstract: We present a novel view on the morphology and dynamical state of ten prominent, nearby (≤ 500 pc), and young (∼30−300 Myr) open star clusters with Gaia DR2:

Cited by 112 publications

References 125 publications

Stellar clustering shapes the architecture of planetary systems

Stellar clustering shapes the architecture of planetary systems

The 800 pc long tidal tails of the Hyades star cluster

Estimating the ages of open star clusters from properties of their extended tidal tails

Contact Info

Product

Resources

About