What Determines the Typical Mass of Dense Coresin Quiescent, Nonmagnetized Molecular Clouds?

Details What Determines the Typical Mass of Dense Coresin Quiescent, Nonmagnetized Molecular Clouds? What Determines the Typical Mass of Dense Coresin Quiescent, Nonmagnetized Molecular Clouds?

Nov 1998

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1998apj...507l.165n&link_type=abstract

The Astrophysical Journal, Volume 507, Issue 2, pp. L165-L169.

Astronomy and Astrophysics

Astronomy

1

Hydrodynamics, Ism: Clouds, Molecular Processes, Stars: Formation

Scientific paper

By means of one-dimensional simulations, we study the collapse of a quiescent, nonmagnetized filamentary molecular cloud, taking into account the heating and cooling processes. At the initial state, the model cloud has the central density of n_c=10^3 cm^-3 and temperature of T=15 K. We follow its contraction until the central density reaches n_c~=10^10 cm^-3. The cloud contracts mainly due to the CO line cooling and cooling by gas-dust interactions. During the contraction, the cloud temperature stays nearly constant at T~10 K because the net radiative cooling rate nearly balances with the heating by gravitational compression, which is the most efficient heating source. When the central density exceeds 10^4-10^5 cm^-3, a shock wave is formed at r~0.05 pc. The shock wave separates the cloud into two parts, i.e., a dense spindle and a diffuse envelope. The spindle slowly contracts due to cooling by gas-dust interactions. During the contraction, the outer part of the spindle has a power-law density distribution of rho~r^-2, which is different from that expected by an isothermal model,rho~r^-4. Applying linear theory, we find that the collapsing spindle is likely to fragment into dense cores by the stage that the central density reaches n_c~10^8-10^9 cm^-3 if the amplitude of the perturbation is greater than A>~10^-2. The masses of the dense cores depend on the initial amplitude of the perturbation. When the initial amplitude of the perturbation is small (A<~10^-1), the spindle fragments into cores with mass 0.1-0.5 M_solar. On the other hand, when the spindle has relatively large inhomogeneity (A~10^-1), it fragments into cores with mass ~10 M_solar.

Affiliated with

Also associated with

No associations

Rating

What Determines the Typical Mass of Dense Coresin Quiescent, Nonmagnetized Molecular Clouds? does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with What Determines the Typical Mass of Dense Coresin Quiescent, Nonmagnetized Molecular Clouds?, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and What Determines the Typical Mass of Dense Coresin Quiescent, Nonmagnetized Molecular Clouds? will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1074701