Small-scale Dynamo in Supernova-driven Interstellar Turbulence
نویسندگان
چکیده
Magnetic fields grow quickly even at early cosmological times, suggesting the action of a small-scale dynamo (SSD) in interstellar medium galaxies. Many studies have focused on idealized turbulent driving SSD. Here we simulate more realistic supernova-driven turbulence to determine whether it can drive an field growth occurring our models appears inconsistent with simple tangling magnetic fields, but consistent SSD action, reproducing and confirming by Balsara et al. (2004) that did not include physical resistivity $\eta$. We vary $\eta$, as well numerical resolution supernova rate, $\dot\sigma$, delineate regime which occurs. For given $\dot\sigma$ find convergence for rate parsec. $\dot\sigma\simeq\dot\sigma_{\rm sn}$, $\dot\sigma_{\rm sn}$ solar neighbourhood critical below occurs is $0.005>\eta_{\rm crit}>0.001\,\rm kpc^{-1}\,\rm km s^{-1}$, this increases rate. Across modelled range 0.5--4 pc $\eta<\eta_{\rm crit}$, saturates about 5% kinetic energy equipartition, independent In $0.2\dot\sigma_{\rm sn}\leq \dot\sigma\leq8\dot\sigma_{\rm $\dot\sigma$. SSDs commonly exhibit erratic growth.
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ژورنال
عنوان ژورنال: The astrophysical journal
سال: 2021
ISSN: ['2041-8213', '2041-8205']
DOI: https://doi.org/10.3847/2041-8213/abed59