The ultra-diffuse galaxy NGC 1052-DF2 with MUSE I. Kinematics of the stellar body

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F19%3A10406196" target="_blank" >RIV/00216208:11320/19:10406196 - isvavai.cz</a>

Výsledek na webu

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=p0sLPK2KKz" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=p0sLPK2KKz</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1051/0004-6361/201834909" target="_blank" >10.1051/0004-6361/201834909</a>

Jazyk výsledku

angličtina

Název v původním jazyce

The ultra-diffuse galaxy NGC 1052-DF2 with MUSE I. Kinematics of the stellar body

Popis výsledku v původním jazyce

The so-called ultra-diffuse galaxy NGC 1052-DF2 was announced to be a galaxy lacking dark matter based on a spectroscopic study of its constituent globular clusters. Here we present the first spectroscopic analysis of the stellar body of this galaxy using the MUSE integral-field spectrograph at the (ESO) Very Large Telescope. The MUSE datacube simultaneously provides DF2&apos;s stellar velocity field and systemic velocities for seven globular clusters (GCs). We further discovered three planetary nebulae (PNe) that are likely part of this galaxy. While five of the clusters had velocities measured in the literature, we were able to confirm the membership of two more candidates through precise radial velocity measurements, which increases the measured specific frequency of GCs in DF2. The mean velocity of the diffuse stellar body, 1792.9(+1.4)(-1.8) 14 km s(-1), is consistent with the mean globular cluster velocity. We detect a weak but significant velocity gradient within the stellar body, with a kinematic axis close to the photometric major axis, making it a prolate-like rotator. We estimate a velocity dispersion from the clusters and PNe of sigma(int) = 10.6(-2.3)(+3:9) km s(-1). The velocity dispersion sigma(DF2)*(R-e) for the stellar body within one effective radius is 10.8(-4.0)(+3.2) km s(-1). Considering various sources of systemic uncertainties, this central value varies between 5 and 13 km s-1, and we conservatively report a 95% confidence upper limit to the dispersion within one R-e of 21 km s(-1). We provide updated mass estimates based on these dispersions corresponding to the different distances to NGC 1052-DF2 that have been reported in the recent literature.

Název v anglickém jazyce

The ultra-diffuse galaxy NGC 1052-DF2 with MUSE I. Kinematics of the stellar body

Popis výsledku anglicky

The so-called ultra-diffuse galaxy NGC 1052-DF2 was announced to be a galaxy lacking dark matter based on a spectroscopic study of its constituent globular clusters. Here we present the first spectroscopic analysis of the stellar body of this galaxy using the MUSE integral-field spectrograph at the (ESO) Very Large Telescope. The MUSE datacube simultaneously provides DF2&apos;s stellar velocity field and systemic velocities for seven globular clusters (GCs). We further discovered three planetary nebulae (PNe) that are likely part of this galaxy. While five of the clusters had velocities measured in the literature, we were able to confirm the membership of two more candidates through precise radial velocity measurements, which increases the measured specific frequency of GCs in DF2. The mean velocity of the diffuse stellar body, 1792.9(+1.4)(-1.8) 14 km s(-1), is consistent with the mean globular cluster velocity. We detect a weak but significant velocity gradient within the stellar body, with a kinematic axis close to the photometric major axis, making it a prolate-like rotator. We estimate a velocity dispersion from the clusters and PNe of sigma(int) = 10.6(-2.3)(+3:9) km s(-1). The velocity dispersion sigma(DF2)*(R-e) for the stellar body within one effective radius is 10.8(-4.0)(+3.2) km s(-1). Considering various sources of systemic uncertainties, this central value varies between 5 and 13 km s-1, and we conservatively report a 95% confidence upper limit to the dispersion within one R-e of 21 km s(-1). We provide updated mass estimates based on these dispersions corresponding to the different distances to NGC 1052-DF2 that have been reported in the recent literature.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10308 - Astronomy (including astrophysics,space science)

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2019

Kód důvěrnosti údajů

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

Název periodika

Astronomy &amp; Astrophysics [online]

ISSN

1432-0746

e-ISSN

—

Svazek periodika

625

Číslo periodika v rámci svazku

květen

Stát vydavatele periodika

FR - Francouzská republika

Počet stran výsledku

12

Strana od-do

A76

Kód UT WoS článku

000468027400001

EID výsledku v databázi Scopus

—