Is $X$ a Borel subset of $\beta X$?

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Consider a Tychonoff space $X$ and $\beta X$ its Stone-$\check{\rm C}$ech compactification. I'm currently studying the existence of certain types of regular Borel measures on $X$. Since it's much simpler to obtain regular Borel meaures for a compact, I'd like to obtain them for $\beta X$, and then consider the restriction to $X$. To do so, I'd like to know whether $X$ is a Borel subset of $\beta X$.

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It need not be. I’ve not read the paper, but K.C. Goswami has a paper Density topology on R is not a Borel subset of its Stone-Čech compactification [PDF]. It uses results from Ichiro Amemiya, Susumu Okada, Yoshiaki Okazaki, Pre-Radon measures on topological spaces [PDF], which I have also not read.