Numerical modeling of light-induced drift in a cloud of interstellar gas

Numerical modeling of the interstellar gas in galaxies is an effective approach to infer galactic gravitational structure. This is because the dynamical behavior of gas is very sensitive to the background gravitational potential. Since the dynamical resonances depend closely on the mass distribution and the pattern speed of the non-axisymmetric component, it is possible to determine these dynamical parameters by comparison of numerical simulations and gas observations.

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Interstellar gas in the central region of the Galaxy

Symposium - International Astronomical Union ◽

10.1017/s0074180900101032 ◽

1967 ◽

Vol 31 ◽

pp. 239-251 ◽

Cited By ~ 3

Author(s):

F. J. Kerr

Keyword(s):

Central Region ◽

Galactic Plane ◽

Neutral Hydrogen ◽

Continuum Emission ◽

Galactic Centre ◽

Interstellar Gas ◽

Hydrogen Recombination ◽

The Galaxy ◽

Centre Region ◽

The Relationship

A review is given of information on the galactic-centre region obtained from recent observations of the 21-cm line from neutral hydrogen, the 18-cm group of OH lines, a hydrogen recombination line at 6 cm wavelength, and the continuum emission from ionized hydrogen.Both inward and outward motions are important in this region, in addition to rotation. Several types of observation indicate the presence of material in features inclined to the galactic plane. The relationship between the H and OH concentrations is not yet clear, but a rough picture of the central region can be proposed.

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Supernovae and interstellar gas dynamics

Symposium - International Astronomical Union ◽

10.1017/s0074180900100774 ◽

1967 ◽

Vol 31 ◽

pp. 117-119

Author(s):

F. D. Kahn ◽

L. Woltjer

Keyword(s):

Lower Limit ◽

High Velocity ◽

Gas Dynamics ◽

Interstellar Cloud ◽

Interstellar Gas ◽

Random Motions ◽

Relativistic Particles

The efficiency of the transfer of energy from supernovae into interstellar cloud motions is investigated. A lower limit of about 0·002 is obtained, but values near 0·01 are more likely. Taking all uncertainties in the theory and observations into account, the energy per supernova, in the form of relativistic particles or high-velocity matter, needed to maintain the random motions in the interstellar gas is estimated as 1051·4±1ergs.

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Remarks on the diffuse interstellar lines

Symposium - International Astronomical Union ◽

10.1017/s0074180900100750 ◽

1967 ◽

Vol 31 ◽

pp. 91-93 ◽

Cited By ~ 4

Author(s):

G. Herzberg

Keyword(s):

Hydrogen Atoms ◽

Interstellar Gas

It is suggested that the diffuse interstellar lines are produced in the interstellar gas by molecules consisting of a few hydrogen atoms and one other atom, such as CH4+ or NH4. Diffuseness of the lines is assumed to result from predissociation of these molecules.

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Prediction of LPCVD silicon film microstructure from local operating conditions using numerical modeling

Journal de Physique IV (Proceedings) ◽

10.1051/jp4:1999822 ◽

1999 ◽

Vol 09 (PR8) ◽

pp. Pr8-181-Pr8-188 ◽

Cited By ~ 1

Author(s):

A. Dollet ◽

B. Caussat ◽

J. P. Couderc

Keyword(s):

Numerical Modeling ◽

Silicon Film ◽

Operating Conditions ◽

Film Microstructure

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Investigation of Morphosedimentary Processes on a Schematic Louisiana Barrier Island Using Process-Based Numerical Modeling

Coastal Sediments '07 ◽

10.1061/40926(239)51 ◽

2007 ◽

Author(s):

T. Campbell ◽

B. de Sonneville ◽

L. Benedet ◽

D. J. W. Walstra ◽

C. W. Finkl

Keyword(s):

Numerical Modeling ◽

Barrier Island

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Numerical Modeling of Hurricane-Induced Extreme Wave Heights in Pensacola Bay

Coastal Hazards ◽

10.1061/9780784412664.007 ◽

2013 ◽

Author(s):

Wenrui Huang ◽

Yuan He ◽

Shuguang Liu

Keyword(s):

Numerical Modeling ◽

Extreme Wave ◽

Wave Heights

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SIMULATION OF ELECTRICAL MONITORING OF DAMS WITH LEAKAGE WITH A TRANSVERSE PLACEMENT OF THE MEASURING INSTALLATION

Eurasian Journal of Mathematical and Computer Applications ◽

10.32523/2306-6172-2020-8-4-69-82 ◽

2020 ◽

Vol 8 (4) ◽

pp. 69-82

Author(s):

D.S. Rakisheva ◽

◽

B.G. Mukanova ◽

I.N. Modin ◽

◽

...

Keyword(s):

Numerical Modeling ◽

Water Level ◽

Electrical Resistivity Tomography ◽

Resistivity Tomography ◽

Measuring Installation ◽

Basic Functions ◽

Tomography Method ◽

Dam Monitoring ◽

The Mathematical Model ◽

Measurement Line

Numerical modeling of the problem of dam monitoring by the Electrical Resistivity Tomography method is carried out. The mathematical model is based on integral equations with a partial Fourier transform with respect to one spatial variable. It is assumed that the measurement line is located across the dam longitude. To approximate the shape of the dam surface, the Radial Basic Functions method is applied. The influence of locations of the water-dam, dam-basement, basement-leakage boundaries with respect to the sounding installation, which is partially placed under the headwater, is studied. Numerical modeling is carried out for the following varied parameters: 1) water level at the headwater; 2) the height of the leak; 3) the depth of the leak; 4) position of the supply electrode; 5) water level and leaks positions are changing simultaneously. Modeling results are presented in the form of apparent resistivity curves, as it is customary in geophysical practice.

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