Stellar streams as gravitational experiments I. The case of Sagittarius

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F17%3A10371070" target="_blank" >RIV/00216208:11320/17:10371070 - isvavai.cz</a>

Result on the web

<a href="http://dx.doi.org/10.1051/0004-6361/201730531" target="_blank" >http://dx.doi.org/10.1051/0004-6361/201730531</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1051/0004-6361/201730531" target="_blank" >10.1051/0004-6361/201730531</a>

Result language

angličtina

Original language name

Stellar streams as gravitational experiments I. The case of Sagittarius

Original language description

Tidal streams of disrupting dwarf galaxies orbiting around their host galaxy offer a unique way to constrain the shape of galactic gravitational potentials. Such streams can be used as &quot;leaning tower&quot; gravitational experiments on galactic scales. The most well-motivated modification of gravity proposed as an alternative to dark matter on galactic scales is Milgromian dynamics (MOND), and we present here the first ever N-body simulations of the dynamical evolution of the disrupting Sagittarius dwarf galaxy in this framework. Using a realistic baryonic mass model for the Milky Way, we attempt to reproduce the present-day spatial and kinematic structure of the Sagittarius dwarf and its immense tidal stream that wraps around the Milky Way. With very little freedom on the original structure of the progenitor, constrained by the total luminosity of the Sagittarius structure and by the observed stellar mass-size relation for isolated dwarf galaxies, we find reasonable agreement between our simulations and observations of this system. The observed stellar velocities in the leading arm can be reproduced if we include a massive hot gas corona around the Milky Way that is flattened in the direction of the principal plane of its satellites. This is the first time that tidal dissolution in MOND has been tested rigorously at these mass and acceleration scales.

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

2017

Confidentiality

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

Name of the periodical

Astronomy &amp; Astrophysics [online]

ISSN

1432-0746

e-ISSN

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Volume of the periodical

603

Issue of the periodical within the volume

červenec

Country of publishing house

FR - FRANCE

Number of pages

11

Pages from-to

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UT code for WoS article

000406619100107

EID of the result in the Scopus database

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