# How to convert quasar flux time series from observed frame to rest frame?

I have flux time series of quasars in the observed frame and want to convert it in the rest or quasar frame. Any one who can help? Thanks

• I am not familiar with quasars. In general, converting fluxes from an observed frame to a rest frame requires following consideration: extinction correction, cosmological expansion, k-correction. – Kornpob Bhirombhakdi Oct 25 '18 at 4:31
• As you mention that you have time series, I guess that you worry about cosmic time dilation (i.e., what happens to the time axis) more than about what happens to the flux. If true, you could clarify this in the question. – mtewes Apr 23 '19 at 7:57

I am not familiar with quasars. In general, converting fluxes from an observed frame to a rest frame requires following consideration: extinction correction, cosmological expansion, k-correction. I think the simplest form is $$f_{rest} = (1 + z)^n f_{obs}$$ where $$z$$ is redshift and $$n$$ is some integer depending on how to express the unit of fluxes. This considers only the cosmological expansion. But, I am not sure if this transformation is valid with your quasars because they might be too far that $$(1+z)^n$$ is no longer a good approximation.