Self-similar shocks in polytropic gas flows around star-forming regions

@article{Lou2006SelfsimilarSI,
  title={Self-similar shocks in polytropic gas flows around star-forming regions},
  author={Yu-qing Lou and Yang Gao},
  journal={Monthly Notices of the Royal Astronomical Society},
  year={2006},
  volume={373},
  pages={1610-1618}
}
  • Y. Lou, Yang Gao
  • Published 28 September 2006
  • Physics
  • Monthly Notices of the Royal Astronomical Society
Self-similar shock solutions in spherically symmetric polytropic gas flows are constructed and analysed in contexts of protostar formation processes. Among other possible solutions, we model a similarity shock across the sonic critical curve with an inner free-fall core collapse and a simultaneous outer expansion of the extended envelope; the separation or stagnation surface between these two flow zones travels outwards in a self-similar manner at a variable speed. One readily obtains accretion… 

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References

SHOWING 1-10 OF 52 REFERENCES

Shocked Self-similar Collapses and Flows in Star Formation Processes

We propose self-similar shocked flow models for certain dynamical evolution phases of young stellar objects, "champagne flows" of H II regions surrounding OB stars, and shaping processes of planetary

Spherical isothermal self-similar shock flows

We explore self-similar dynamical processes in a spherical isothermal self-gravitational fluid with an emphasis on shocks and outline astrophysical applications of such shock solutions. The previous

Self-similar collapse of isothermal spheres and star formation.

We consider the problem of the gravitational collapse of isothermal spheres by applying the similarity method to the gas-dynamic flow. We argue that a previous solution obtained by Larson and Penston

Protostellar Collapse with a Shock

We reexamine both numerically and analytically the collapse of the singular isothermal sphere in the context of low-mass star formation. We consider the case where the onset of collapse is initiated

Envelope expansion with core collapse - III. Similarity isothermal shocks in a magnetofluid

We explore magnetohydrodynamic (MHD) solutions for envelope expansions with core collapse (EECC) with isothermal MHD shocks in a quasi-spherical symmetry, and outline potential astrophysical

Envelope expansion with core collapse – I. Spherical isothermal similarity solutions

We investigate self-similar dynamical processes in an isothermal self-gravitational fluid with spherical symmetry. With reference to the earlier complementary solution results of Larson, Penston,

Gravitational Collapse and Star Formation in Logotropic and Nonisothermal Spheres

We present semianalytical similarity solutions for the inside out, expansion-wave collapse of initially virialized gas clouds with nonisothermal equations of state. Results are given for the family

New self-similar solutions of polytropic gas dynamics

We explore semicomplete self-similar solutions for the polytropic gas dynamics involving self-gravity under spherical symmetry, examine behaviours of the sonic critical curve and present new

Self-similar Champagne Flows in H II Regions

We consider the idealized expansion of an initially self-gravitating, static, singular, isothermal cloud core. For t ≥ 0, the gas is ionized and heated to a higher uniform temperature by the

Generalized Collapse Solutions with Nonzero Initial Velocities for Star Formation in Molecular Cloud Cores

Motivated by recent observations that show that starless molecular cloud cores exhibit subsonic inward velocities, we revisit the collapse problem for polytropic gaseous spheres. In particular, we
...