# Research

### Mass-Radius Relation of Neutron Stars

• I have been reading the paper in order to check whether my code (TOV solver) follows the equation of state (EOS):

$\rho = 2\sqrt{p} - p$

• Units in the EOS are used the geometrized( $c=G=1$ ) units, so I need to convert it into cgs units:

$\rho_{cgs} = \rho_{geo} \times \frac{c^2}{G}$

$p_{cgs} = p_{geo} \times \frac{c^4}{G}$

• I easily put this calculation in my TOV solver, but the result is not that I expected. I looks like another term was multiplied (by 1523920). But I don’t know this term means.
• And I was thinking how can I get mass density and pressure profiles in RNS code. I guess that TOV equation part is in ‘equil.c’, so I think I can get these profiles by editing TOV function in ‘equil.c’ file.

# Study

### Astronomy & Astrophysics

• I have read the Astrobites article. It is interesting that the X-ray 3.5 keV signal could be an indicator of the dark matter.

### English

• I have added 1 TOEFL essay and 1 GRE essay.
• I have studied 37 words, 19 sentences, 2 TOEFL essays, and 2 GRE essays using Anki.

### General Science

• I have read the Nature Briefing article.
• I have watched 1 SciShow, 1 SciShow Space on YouTube.