An examination of large-scale galactic effects on molecular cloud properties in NGC 628: the significant impact of tidal effects from neighbouring material on the evolution of molecular clouds

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985815%3A90106%2F25%3A00646706" target="_blank" >RIV/67985815:90106/25:00646706 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.1093/mnras/staf201" target="_blank" >https://doi.org/10.1093/mnras/staf201</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1093/mnras/staf201" target="_blank" >10.1093/mnras/staf201</a>

Jazyk výsledku

angličtina

Název v původním jazyce

An examination of large-scale galactic effects on molecular cloud properties in NGC 628: the significant impact of tidal effects from neighbouring material on the evolution of molecular clouds

Popis výsledku v původním jazyce

The physical factors that influence the development of molecular cloud's density contrast are connected to those that affect star formation in the galaxy. For NGC 628 (M74), the proportion of high- and low-density contrast clouds initially increases with the distance to the galactic centre (R-G) and then keeps relatively stable. Spiral arms, bubbles, and magnetic fields are not responsible for the variations in density contrast observed among molecular clouds. The effects of shear and tides calculated from the galactic rotation curve consistently decrease as R-G increases, and the shear effect can be neglected. We further studied the tidal effects of the neighbouring material on each cloud using the tidal tensor analysis and the pixel-by-pixel computation, after combining molecular gas, atomic gas, and stellar mass surface density maps. When R-G< 4 kpc, the tidal strengths derived from the pixel-by-pixel computation decrease as RG increases, and then remains relatively constant when R-G> 4 kpc. This aligns well with the dependence of the proportion of high- and low-density contrast clouds on RG. Therefore, the tidal effects of neighbouring material have a significant impact on the development of molecular cloud's density contrast. A key factor contributing to the low star formation rate in the galactic centre is the excessive tidal influences from neighbouring material on molecular clouds, which hinder the gravitational collapse within these clouds, resulting in low density contrasts. The tidal effects from neighbouring material may also be a significant contributing factor to the slowing down of a pure free-fall gravitational collapse for gas structures on galaxy-cloud scales revealed in our previous works by velocity gradient measurements.

Název v anglickém jazyce

An examination of large-scale galactic effects on molecular cloud properties in NGC 628: the significant impact of tidal effects from neighbouring material on the evolution of molecular clouds

Popis výsledku anglicky

The physical factors that influence the development of molecular cloud's density contrast are connected to those that affect star formation in the galaxy. For NGC 628 (M74), the proportion of high- and low-density contrast clouds initially increases with the distance to the galactic centre (R-G) and then keeps relatively stable. Spiral arms, bubbles, and magnetic fields are not responsible for the variations in density contrast observed among molecular clouds. The effects of shear and tides calculated from the galactic rotation curve consistently decrease as R-G increases, and the shear effect can be neglected. We further studied the tidal effects of the neighbouring material on each cloud using the tidal tensor analysis and the pixel-by-pixel computation, after combining molecular gas, atomic gas, and stellar mass surface density maps. When R-G< 4 kpc, the tidal strengths derived from the pixel-by-pixel computation decrease as RG increases, and then remains relatively constant when R-G> 4 kpc. This aligns well with the dependence of the proportion of high- and low-density contrast clouds on RG. Therefore, the tidal effects of neighbouring material have a significant impact on the development of molecular cloud's density contrast. A key factor contributing to the low star formation rate in the galactic centre is the excessive tidal influences from neighbouring material on molecular clouds, which hinder the gravitational collapse within these clouds, resulting in low density contrasts. The tidal effects from neighbouring material may also be a significant contributing factor to the slowing down of a pure free-fall gravitational collapse for gas structures on galaxy-cloud scales revealed in our previous works by velocity gradient measurements.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10308 - Astronomy (including astrophysics,space science)

Projekt

—

Návaznosti

—

Rok uplatnění

2025

Kód důvěrnosti údajů

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

Název periodika

Monthly Notices of the Royal Astronomical Society

ISSN

0035-8711

e-ISSN

1365-2966

Svazek periodika

537

Číslo periodika v rámci svazku

2

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

11

Strana od-do

2232-2242

Kód UT WoS článku

001415521800001

EID výsledku v databázi Scopus

2-s2.0-85217517266