Clumpy Flows in Protoplanetary and Planetary Nebulae

نویسندگان

  • Alexei Y. Poludnenko
  • Sorin Mitran
چکیده

Many astrophysical flows occur in inhomogeneous media. We briefly discuss some general properties of the adiabatic and radiative inhomogeneous systems and discuss the relevance of those properties to the planetary nebulae systems. We then focus on radiative hypersonic bullets and the applicability of this model to planetary and protoplanetary systems such as CRL 618, NGC 6543, Hen 3-1475.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

H2 Morphology of Young Planetary Nebulae

The distributions of H2 1-0 S(l) emission in the young planetary nebulae BD +30°3639 and NGC 7027 show ~triking similarities: both have limb-brightened arcs of H2 emission with radii that are about twice those of ~h~ir H; II regions. The extended H2 emission in both nebulae is attributed to a photodissociation region. Thi.s implies that the neutral envelopes of these young planetaries extend we...

متن کامل

Resolved shocks in clumpy media

We study the structure of shocks in clumpy media, using a multifluid formalism. As expected, shocks broaden as they weaken: for sufficiently weak shocks, no viscous sub-shock appears in the structure. This has significant implications for the survival of dense clouds in regions overrun by shocks in a wide range of astrophysical circumstances , from planetary nebulae to the nuclei of starburst g...

متن کامل

The shaping effect of collimated fast outflows in the Egg nebula

We present high angular resolution observations of the HC3N J=5–4 line from the Egg nebula, which is the archetype of protoplanetary nebulae. We find that the HC3N emission in the approaching and receding portion of the envelope traces a clumpy hollow shell, similar to that seen in normal carbon rich envelopes. Near the systemic velocity, the hollow shell is fragmented into several large blobs ...

متن کامل

Structured, Dynamo Driven Stellar and Disc Winds

Considerable progress has been made in understanding the hydrodynamics, but only to a certain extent the magnetohydrodynamics, of shaping bipolar outflows forming protoplanetary nebulae (PPNs) and planetary nebulae (PNs). In particular, Blackman et al. (2001b,2001a) point out two problems related to the formation of PNs and PPNs, regarding the formation of multipolar structures and the origin o...

متن کامل

Dual Axisymmetry in Proto-Planetary Nebula Reflection Nebulosities: Results from an HST Snapshot Survey of PPN Candidates

We summarize results of our HST imaging survey of protoplanetary nebula (PPN) candidates, in which we discovered two types of axisymmetric reflection nebulosities. The Star-Obvious Low-level-Elongated (SOLE) nebulae show a bright central star embedded in a smooth, faint extended nebulosity, whereas the DUst-Prominent Longitudinally-EXtended (DUPLEX) nebulae have remarkable bipolar structure wit...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2003