Nucleus-acoustic solitary waves in self-gravitating degenerate quantum plasmas

Abstract

Nucleus-acoustic (NA) solitary waves (SWs) propagating in a self-gravitating degenerate quantum plasma (SDQP) system (containing non-relativistically degenerate heavy and light nuclei, and non-/ultra-relativistically degenerate electrons) have been theoretically investigated. The modified Korteweg-de Vries (mK-dV) equation has been derived for both planar and non-planar geometry by employing the reductive perturbation technique. It is shown that the NA SWs exist with positive (negative) electrostatic (self-gravitational) potential. It is also observed that the effects of non-/ultra-relativistically degenerate electron pressure, dynamics of non-relativistically light nuclei, spherical geometry, etc. significantly modify the basic features (e.g., amplitude, width, speed, etc.) of the NA SWs. The applications of our results, which are relevant to astrophysical compact objects, like white dwarfs and neutron stars, are briefly discussed.

Planar and non-planar nucleus-acoustic solitary waves in warm degenerate multi-nucleus plasmas

“…Recently, a number of theoretical investigations (Mamun, Amina & Schlickeiser 2016Zaman et al 2017Zaman et al , 2018Chowdhury et al 2018;Jannat & Mamun 2018a,b;Das & Karmakar 2019) have been made of the nonlinear propagation of NA waves in degenerate plasma systems. Mamun et al (2016Mamun et al ( , 2017 considered the strongly (Mamun et al 2016) and weakly (Mamun et al 2017) coupled heavy nucleus fluid, and studied the small-amplitude heavy NA shock waves (Mamun et al 2016) and solitary waves (SWs) (Mamun et al 2017) in an absolutely cold degenerate electron-light nucleus plasma system.…”

“…These shock waves and SWs (Mamun et al 2016(Mamun et al , 2017 are associated with the dynamics of the heavy nucleus species, but not with that of the light nucleus species. Zaman et al (2017Zaman et al ( , 2018 have examined the effects of non-planar geometry on the NA shock (Zaman et al 2017) and solitary (Zaman et al 2018) waves propagating in absolutely cold degenerate electron-nucleus plasma systems. On the other hand, Jannat & Mamun (2018a,b) considered an absolutely cold degenerate plasma system containing cold degenerate electron species and cold dissipative (Jannat & Mamun 2018a) and non-dissipative (Jannat & Mamun 2018b) light nucleus species, and studied the effects of the stationary heavy nucleus species on the NA shock (Jannat & Mamun 2018a) and solitary (Jannat & Mamun 2018b) waves.…”

“…The works highlighted above are valid only for absolutely cold degenerate plasma species, but are not valid for degenerate plasma species at finite temperature, particularly for hot white dwarfs (Dufour et al 2008(Dufour et al , 2011Werner & Rauch 2015;Werner, Rauch & Reindl 2019;Koester, Kepler & Irwin 2020). To overcome this limitation in previously published works (Mamun et al 2016(Mamun et al , 2017Zaman et al 2017Zaman et al , 2018Chowdhury et al 2018;Jannat & Mamun 2018a,b;Das & Karmakar 2019), the equation of state for a degenerate plasma at finite temperature (Manfredi 2005;Vavrukh & Smerechynskyi 2012;Hossain & Mandal 2019) is derived by quantum field theory (Hossain & Mandal 2019) and by introducing two parameters, namely σ j = m j c 2 /E Fj and σ Tj = k B T j /E Fj , where E Fj (T j ) is the the Fermi energy (temperature) of species j with k B being the Boltzmann constant. The equation of state (1.1) for plasma species j at finite temperature T j can, therefore, be modified as…”

“…Recently, a number of theoretical investigations (Mamun, Amina & Schlickeiser 2016, 2017; Zaman et al. 2017, 2018; Chowdhury et al. 2018; Jannat & Mamun 2018 a , b ; Sultana & Schlickeiser 2018; Sultana et al.…”

“…Zaman et al. (2017, 2018) have examined the effects of non-planar geometry on the NA shock (Zaman et al. 2017) and solitary (Zaman et al.…”