Skip navigation

Épsilon Cephei

What I have done in this section is to find the period and the absolute magnitude (M) of different Cepheids (505) and I have put it in an excel, where I have been able to obtain a graph and an equation that allows me to calculate the absolute magnitude (M ) of any Cepheid from its period.

Then, I have calculated the absolute magnitude (M), with the excel equation and with the general formula of the ESO / ESA book, of Épsilon Cephei found in the constellation of Cepheus.

Then, what I have done has been to calculate the distance of this Cepheid with the general formula of the ESO / ESA book

To finish this section, what I have done has been with the rextester program I have copied the magnitude-period of 44 Cepheids to obtain a graph and I have done the same thing again but copying the R-period of the same 44 Cepheids to obtain another graph. In these two sections, I have put the period of my Cepheid so that I can calculate the magnitude and R of my Cepheid.

Results with screenshots:

PERIOD-MAGNITUDE:

PERIOD-R:

As you can see, not all Cepheids correspond to the line, but some stand out. This is because there are two types of Cepheids:

  • Type I (Classical) Cepheids.
  • Type II (W Vigins) Cepheids.

The main difference between these types of cepheids is that Classical cepheids have more luminosity than the ones that are types II.

I have searched the google schoolar if there are formulas, from other scientists, similar to mine.

The formulas that I have found are the following:

:

The websites where I have found the formulas are the following:

http://articles.adsabs.harvard.edu/pdf/1992SvAL...18..207B 

https://iopscience.iop.org/article/10.3847/1538-4357/aa7565/meta 

http://articles.adsabs.harvard.edu/pdf/1971ApJ...167..293S