Bulk viscosity in a neutron star mantle
Bulk viscosity in a neutron star mantle
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中子星地幔中的体积粘度
DOI：
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发表时间：
2018
影响因子：
4.8
通讯作者：
P. Haensel
中科院分区：
文献类型：
--
作者：
D. Yakovlev;M. Gusakov;P. Haensel
本文研究了振荡中子星星地幔与恒星核边界附近非球形核的两个相（反意大利面相和瑞士奶酪相）的体粘滞系数。体粘滞系数是由非平衡Urca中微子锡永过程产生的。在地幔中，直接Urca过程可能是开放的（Gusakov等人，2004），如果中子和质子在由非球形原子核的晶格产生的周期势中运动（这允许核子具有大的准动量并满足直接Urca动量守恒）。这种体粘滞度可以支配由于在外部恒星核心中的修改后的Urca过程和剪切粘滞度。体粘滞系数强烈地依赖于温度、振荡频率和核子超流性。地幔中增强的体粘滞系数可以控制中子星星振荡的传播和衰减。
We study the bulk viscosity in two (anti-spaghetti and Swiss cheese) phases of non- spherical nuclei in the mantle of an oscillating neutron star near the boundary with the stellar core. The bulk viscosity is produced by non-equilibrium Urca neutrino emis- sion processes. In the mantle, the direct Urca process may be open (Gusakov et al., 2004) if neutrons and protons move in a periodic potential created by a lattice of non- spherical nuclei (which allows the nucleons to have large quasi-momenta and satisfy direct Urca momentum-conservation). This bulk viscosity can dominate over that due to the modified Urca process in the outer stellar core and over the shear viscosity. The bulk viscosity depends strongly on temperature, oscillation frequency and nucleon superfluidity. The enhanced bulk viscosity in the mantle can control propagation and damping of neutron star oscillations.