Research output: Contribution to journal › Article › peer-review
Tilted outer and inner structures in edge-on galaxies? / Мосенков, Александр Владимирович; Смирнов, Антон Александрович; Сильченко, Ольга; Rich, R Michael; Решетников, Владимир Петрович; Kormendy, John.
In: Monthly Notices of the Royal Astronomical Society, Vol. 497, No. 2, 09.2020, p. 2039-2056.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Tilted outer and inner structures in edge-on galaxies?
AU - Мосенков, Александр Владимирович
AU - Смирнов, Антон Александрович
AU - Сильченко, Ольга
AU - Rich, R Michael
AU - Решетников, Владимир Петрович
AU - Kormendy, John
N1 - Publisher Copyright: © 2020 The Author(s).
PY - 2020/9
Y1 - 2020/9
N2 - Tilted and warped discs inside tilted dark matter haloes are predicted from numerical and semi-analytical studies. In this paper, we use deep imaging to demonstrate the likely existence of tilted outer structures in real galaxies. We consider two SB0 edge-on galaxies, NGC 4469 and NGC 4452, which exhibit apparent tilted outer discs with respect to the inner structure. In NGC 4469, this structure has a boxy shape, inclined by APA «a 3° with respect to the inner disc, whereas NGC 4452 harbours a discy outer structure with APA «a 6°. In spite of the different shapes, both structures have surface brightness profiles close to exponential and make a large contribution (~30 per cent) to the total galaxy luminosity. In the case of NGC 4452, we propose that its tilted disc likely originates from a former fast tidal encounter (probably with IC3381). For NGC 4469, a plausible explanation may also be galaxy harassment, which resulted in a tilted or even a tumbling dark matter halo. A less likely possibility is accretion of gas-rich satellites several Gyr ago. New deep observations may potentially reveal more such galaxies with tilted outer structures, especially in clusters. We also consider galaxies, mentioned in the literature, where a central component (a bar or a bulge) is tilted with respect to the stellar disc. According to our numerical simulations, one of the plausible explanations of such observed 'tilts' of the bulge/bar is a projection effect due to a not exactly edge-on orientation of the galaxy coupled with a skew angle of the triaxial bulge/bar.
AB - Tilted and warped discs inside tilted dark matter haloes are predicted from numerical and semi-analytical studies. In this paper, we use deep imaging to demonstrate the likely existence of tilted outer structures in real galaxies. We consider two SB0 edge-on galaxies, NGC 4469 and NGC 4452, which exhibit apparent tilted outer discs with respect to the inner structure. In NGC 4469, this structure has a boxy shape, inclined by APA «a 3° with respect to the inner disc, whereas NGC 4452 harbours a discy outer structure with APA «a 6°. In spite of the different shapes, both structures have surface brightness profiles close to exponential and make a large contribution (~30 per cent) to the total galaxy luminosity. In the case of NGC 4452, we propose that its tilted disc likely originates from a former fast tidal encounter (probably with IC3381). For NGC 4469, a plausible explanation may also be galaxy harassment, which resulted in a tilted or even a tumbling dark matter halo. A less likely possibility is accretion of gas-rich satellites several Gyr ago. New deep observations may potentially reveal more such galaxies with tilted outer structures, especially in clusters. We also consider galaxies, mentioned in the literature, where a central component (a bar or a bulge) is tilted with respect to the stellar disc. According to our numerical simulations, one of the plausible explanations of such observed 'tilts' of the bulge/bar is a projection effect due to a not exactly edge-on orientation of the galaxy coupled with a skew angle of the triaxial bulge/bar.
KW - Galaxies: evolution
KW - Galaxies: formation
KW - Galaxies: haloes
KW - Galaxies: interactions
KW - Galaxies: photometry
KW - Galaxies: structure
KW - DISC GALAXIES
KW - STELLAR HALOES
KW - SPIRAL GALAXIES
KW - galaxies: evolution
KW - galaxies: interactions
KW - galaxies: photometry
KW - DARK-MATTER HALOES
KW - STAR-FORMATION
KW - ACS-VIRGO-CLUSTER
KW - COOL INTERSTELLAR-MEDIUM
KW - galaxies: formation
KW - galaxies: structure
KW - DIGITAL SKY SURVEY
KW - ANGULAR-MOMENTUM DISTRIBUTION
KW - MILKY-WAY
KW - galaxies: haloes
UR - https://academic.oup.com/mnras/article-abstract/497/2/2039/5866843?redirectedFrom=fulltext
UR - http://www.scopus.com/inward/record.url?scp=85095457429&partnerID=8YFLogxK
UR - https://www.mendeley.com/catalogue/1a77f1d5-5669-3396-a4ac-48f88e3d85df/
U2 - 10.1093/mnras/staa1885
DO - 10.1093/mnras/staa1885
M3 - Article
VL - 497
SP - 2039
EP - 2056
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
SN - 0035-8711
IS - 2
ER -
ID: 61089968