The kinematics of star clusters undergoing gas expulsion in Newtonian and Milgroniian dynamics

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F19%3A10406400" target="_blank" >RIV/00216208:11320/19:10406400 - isvavai.cz</a>

Result on the web

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=3196Lw4prX" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=3196Lw4prX</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1093/mnras/stz1519" target="_blank" >10.1093/mnras/stz1519</a>

Result language

angličtina

Original language name

The kinematics of star clusters undergoing gas expulsion in Newtonian and Milgroniian dynamics

Original language description

We study the kinematics of stars in clusters undergoing gas expulsion in standard Newtonian dynamics and also in Milgromian dynamics (MOND). Gas expulsion can explain the observed line-of-sight (LoS) velocity dispersion profile of NGC 2419 in Newtonian dynamics. For a given star formation efficiency (SEE), the shapes of the velocity dispersion profiles, which are normalized by the velocity dispersion at the projected half-mass radius, are almost indistinguishable for different SEE models in Newtonian dynamics. The velocity dispersion of a star cluster in the outer halo of a galaxy can indeed have a strong radial anisotropy in Newtonian dynamics after gas expulsion. MOND displays several different properties from Newtonian dynamics. In particular, the slope of the central velocity dispersion profile is less steep in MOND for the same SFE. Moreover, for a given SFE, more massive embedded cluster models result in more rapidly declining central velocity dispersion profiles for the final star clusters, while less massive embedded cluster models lead to flatter velocity dispersion profiles for the final products. The onset of the radial-orbit instability in post-gas-expulsion MOND models is discussed. SFEs as low as a few per cent, typical of molecular clouds, lead to surviving ultradiffuse objects. Gas expulsion alone is unlikely the physical mechanism for the observed velocity dispersion profile of NGC 2419 in MOND.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10308 - Astronomy (including astrophysics,space science)

Project

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Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2019

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Monthly Notices of the Royal Astronomical Society

ISSN

0035-8711

e-ISSN

—

Volume of the periodical

487

Issue of the periodical within the volume

3

Country of publishing house

GB - UNITED KINGDOM

Number of pages

13

Pages from-to

4012-4024

UT code for WoS article

000478053200077

EID of the result in the Scopus database

2-s2.0-85072288824