Nonlinear generation of one-armed spirals in self-gravitating disks

被引:25
作者
Laughlin, G
Korchagin, V
机构
[1] National Astronomical Observatory, Mitaka
关键词
circumstellar matter; hydrodynamics; instabilities; solar system; formation;
D O I
10.1086/177015
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
Single-armed spiral instabilities may play an important role in self-gravitating disks. However, past studies have indicated that disks which are less massive than an embedded central star are in general linearly stable to m = 1 perturbations. In this paper, we outline how the nonlinear interaction of two growing modes with azimuthal mode numbers m = n and m = n + 1 can excite the development of a one-armed disturbance which grows exponentially at a rate equal to the sum of the growth rates of the two linearly unstable modes. Within the context of a second order, semianalytic analysis, we discuss the special case of a unique nonwinding, exponentially growing solution, and then we consider further solutions based on physically relevant initial conditions. We find that the nonwinding solution describes the general dynamics of the mode at later times. We then compare the results of our nonlinear analysis with hydrodynamic simulations, illustrating that the process we have considered is indeed an important effect.
引用
收藏
页码:855 / 868
页数:14
相关论文
共 19 条
[1]   ECCENTRIC GRAVITATIONAL INSTABILITIES IN NEARLY KEPLERIAN DISKS [J].
ADAMS, FC ;
RUDEN, SP ;
SHU, FH .
ASTROPHYSICAL JOURNAL, 1989, 347 (02) :959-976
[2]   MODAL APPROACH TO THE MORPHOLOGY OF SPIRAL GALAXIES .1. BASIC STRUCTURE AND ASTROPHYSICAL VIABILITY [J].
BERTIN, G ;
LIN, CC ;
LOWE, SA ;
THURSTANS, RP .
ASTROPHYSICAL JOURNAL, 1989, 338 (01) :78-103
[3]   A NEW BINARY FORMATION MECHANISM [J].
BONNELL, IA .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 1994, 269 (03) :837-848
[4]  
Broadbent E. G., 1979, Philosophical Transactions of the Royal Society of London A (Mathematical and Physical Sciences), V290, P353, DOI 10.1098/rsta.1979.0003
[5]  
Churilov S. M., 1981, Soviet Astronomy, V25, P147
[6]  
HEEMSKERK MHM, 1992, ASTRON ASTROPHYS, V260, P161
[7]   NONLINEAR MODULATION OF DENSITY WAVE IN SELF-GRAVITATING SYSTEMS - GAS DYNAMICAL DESCRIPTION [J].
IKEUCHI, S ;
NAKAMURA, T .
PROGRESS OF THEORETICAL PHYSICS, 1976, 55 (05) :1419-1431
[8]   RESONANT 3-WAVE INTERACTIONS OF DENSITY WAVES IN A SELF-GRAVITATING DISK [J].
IKEUCHI, S .
PROGRESS OF THEORETICAL PHYSICS, 1977, 57 (04) :1239-1254
[9]  
KIKUCHI N, 1995, UNPUB
[10]  
KORCHAGIN VI, 1984, SOV ASTRON LETT+, V10, P5