18–23 Mar 2018
Florianopolis, Brazil
America/Sao_Paulo timezone

An introductory study to white dwarfs

20 Mar 2018, 16:00
1h
Florianopolis, Brazil

Florianopolis, Brazil

Speaker

Sílvia Pereira Nunes (Instituto Tecnológico de Aeronáutica - ITA)

Description

White dwarfs are compact objects that stand against gravitational collapse by their internal pressure of degenerate matter. In this work we aimed to perform an introductory study on these stars, using two equations of state: (I) an ideal Fermi gas and (II) the one by Baym Pethick and Sutherland (BPS). In addition, we analyzed these two state equations in two scenarios, the Newtonian and the one from General Relativity, which allowed us to analyze the effects of curved space-time. We also studied a rotating white dwarf, finding a metric for this case. With these two cases, with rotation and static well determined, we introduced the concepts of instability by the turning point criterion and dynamic instability criterion. Finally, with the RNS program, we performed the numerical resolution of the BPS equation of state with ($J=constant$ and $J=0$ respectively) rotation in order to analyze the behavior of the turning point criterion in these two cases. All the numerical resolution of the equations of a non-rotating white dwarf were made using FORTRAN programs written by the author and all the results found were compatible with those of the literature.

Primary author

Sílvia Pereira Nunes (Instituto Tecnológico de Aeronáutica - ITA)

Co-authors

Prof. Marcelo Chiapparini (Universidade do Estado do Rio de Janeiro - UERJ) Prof. Santiago Bergliaffa (Universidade do Estado do Rio de Janeiro - UERJ)

Presentation materials