Turbulent convection and pulsational stability of variable stars: non-adiabatic oscillations of the solar p-modes

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	Turbulent convection and pulsational stability of variable stars: non-adiabatic oscillations of the solar p-modes
	Xiong, DR; Cheng, QL ; Deng, L
刊名	MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
	2000-12-21
卷号	319 期号:4 页码:1079-1093
关键词	convection Sun : oscillations
ISSN号	0035-8711
英文摘要	By using a non-local time-dependent theory of convection, the non-adiabatic oscillations of the radial p-modes of the Sun were calculated. The coupling between convection and oscillation and the influence of departure from radiative equilibrium on oscillations of p-modes were investigated in detail. The results of numerical calculations show that when the coupling between convection and oscillations is ignored, all the low-order radial p-modes with n less than or similar to 10 are pulsationally unstable and all the intermediate- and high-order (n greater than or similar to 11) radial p-modes are pulsationally stable. When the coupling between convection and oscillations is taken into consideration, only the intermediate-order p-modes with 11 n less than or similar to 23 are pulsationally unstable and all the low-order (n less than or similar to 10) and high-order (n greater than or similar to 24) p-modes are pulsationally stable. The behaviour of stability of the solar p-mode oscillations described above is the result of the joint action of radiation and convection on oscillations. In the interior of the convection zone, the thermodynamic coupling between convection and oscillations gives rise to damping of solar oscillations, but at the top of the convection zone, it causes excitation. The thermodynamic coupling between convection and oscillations plays a key role in the stabilization of low-frequency solar p-modes and also in the excitation of the intermediate-order solar p-mode oscillations with periods of about 5 min. The turbulent pressure generally causes excitation. The radiative damping in the outer atmosphere and the turbulent viscosity are the main damping mechanisms of the high-order (nu greater than or similar to 4000 mu Hz) solar p-modes. For the low-order p-mode oscillations with nu less than or similar to 1000 mu Hz, the departure from radiative equilibrium (DRE) does not have a significant effect. With the increase of frequency, the influence of the outer atmosphere and the DRE grows rapidly. The generalized Eddington approximations (GEA) developed by Unno & Spiegel and Mihalas are much better than the usual radiative diffusion approximation. Our conclusion is as follows: the coupling between convection and oscillations is an important excitation and damping mechanism for solar 5-min oscillations. However, it cannot be used to interpret all the observational characteristics of solar p-modes. There must be excitation and damping mechanisms other than the radiation and the 'regular' coupling between convection and oscillations.
学科主题	Astronomy & Astrophysics
WOS标题词	Science & Technology ; Physical Sciences
类目[WOS]	Astronomy & Astrophysics
研究领域[WOS]	Astronomy & Astrophysics
关键词[WOS]	RADIATION-HYDRODYNAMIC EQUATIONS ; STELLAR ENVELOPES ; 5-MINUTE OSCILLATIONS ; STATE ; FREQUENCIES ; EXCITATION ; SEISMOLOGY
收录类别	SCI
语种	英语
WOS记录号	WOS:000166398900011
公开日期	2015-04-20
内容类型	期刊论文
源URL	[http://libir.pmo.ac.cn/handle/332002/11187]
专题	紫金山天文台_院士文集_熊大闰
作者单位	1.Chinese Acad Sci, Purple Mt Observ, Nanjing 210008, Peoples R China 2.Chinese Acad Sci, Natl Astron Observ, Beijing 100101, Peoples R China 3.Chinese Acad Sci, Beijing Astron Observ, Beijing 100101, Peoples R China
推荐引用方式 GB/T 7714	Xiong, DR,Cheng, QL,Deng, L. Turbulent convection and pulsational stability of variable stars: non-adiabatic oscillations of the solar p-modes[J]. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY,2000,319(4):1079-1093.
APA	Xiong, DR,Cheng, QL,&Deng, L.(2000).Turbulent convection and pulsational stability of variable stars: non-adiabatic oscillations of the solar p-modes.MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY,319(4),1079-1093.
MLA	Xiong, DR,et al."Turbulent convection and pulsational stability of variable stars: non-adiabatic oscillations of the solar p-modes".MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 319.4(2000):1079-1093.