How the bar properties affect the induced spiral structure

التفاصيل البيبلوغرافية
العنوان: How the bar properties affect the induced spiral structure
المؤلفون: Garma-Oehmichen, L., Martinez-Medina, L., Hernández-Toledo, H., Puerari, I.
سنة النشر: 2021
المجموعة: Astrophysics
مصطلحات موضوعية: Astrophysics - Astrophysics of Galaxies
الوصف: Stellar bars and spiral arms co-exist and co-evolve in most disc galaxies in the local Universe. However, the physical nature of this interaction remains a matter of debate. In this work, we present a set of numerical simulations based on isolated galactic models aimed to explore how the bar properties affect the induced spiral structure. We cover a large combination of bar properties, including the bar length, axial ratio, mass and rotation rate. We use three galactic models describing galaxies with rising, flat and declining rotation curves. We found that the pitch angle best correlates with the bar pattern speed and the spiral amplitude with the bar quadrupole moment. Our results suggest that galaxies with declining rotation curves are the most efficient forming grand design spiral structure, evidenced by spirals with larger amplitude and pitch angle. We also test the effects of the velocity ellipsoid in a subset of simulations. We found that as we increase the radial anisotropy, spirals increase their pitch angle but become less coherent with smaller amplitude.
Comment: Accepted for publication in MNRAS. 16 pages, 16 figures
نوع الوثيقة: Working Paper
DOI: 10.1093/mnras/stab333
URL الوصول: http://arxiv.org/abs/2102.01134
رقم الأكسشن: edsarx.2102.01134
قاعدة البيانات: arXiv