Mathematical method for the study and teaching of stellar and protostellar structure
Abstract
The purpose of this thesis is to develop a relatively simple yet effective method of teaching stellar and protostellar structure. There are four differential equations describing the structure of a star. They are: These equations are linearly approximated in the following form: W = W_{o} (1 plus or minus wx). Here, W represents the pressure (P), temperature (T), mass (M), and/or luminosity (L) gradients within the star; W represents some initial value of these parameters expanded inwardly or outwardly from an initial point, r_{o;} and w represents what is called the Motz Dimensionless Variables (MDV) which are directly derivable from the above set of equations. They are dimensionless, so, in the expansion, W has the same units as w_{o.} The MDV appear below: As yet, there is no MDV for luminosity owing to the complicating energy generation factor, epsilon. In the above sets of equations, the mean molecular weight is micro; the opacity is kappa; the ratio of gas pressure to total pressure is beta; and the other symbols have their usual meanings. In the above set of equations describing the MDV, if the surface of the star is expanded to larger values, representing earlier, and therefore, protostellar stages of the star, by theoretically halting accretion, no dynamical factors need to be considered. The above set of equations describing a stellar structure in static equilibrium may then be used. This method was designed for college and early graduate students who have never before encountered the topic of stellar structure. This method was taught to a class of college physics majors in a local New York City college. The students had never before seen these equations. After the presentation, they were asked to attempt construction of sample stellar model using this method and also to complete a questionnaire concerning their general academic history and their opinions of the method. According to the questionnaire, most subjects felt that it was effective, yet simple enough, as an introductory method for the topic.
 Publication:

NASA STI/Recon Technical Report N
 Pub Date:
 1988
 Bibcode:
 1988STIN...9011666D
 Keywords:

 Protostars;
 Stellar Composition;
 Stellar Evolution;
 Stellar Structure;
 Dimensionless Numbers;
 Education;
 Luminosity;
 Numerical Analysis;
 Pressure;
 Temperature;
 Astrophysics