اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدModel-independent measurement of the Hubble Constant and the absolute magnitude of Type Ia Supernovae
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In this work, we propose a cosmological model-independent and non-local method to constrain the Hubble Constant $H_0$. Inspired by the quasi cosmological model-independent and $H_0$-free properties of the `shifted Hubble diagram of HII galaxies (HIIGx) defined by Wei et al. (2016), we joint analyze it with the parametric type Ia supernova (SN Ia) Hubble diagram (e.g. the joint-lightcurves-analysis sample, JLA) and get a Bayesian Inference of Hubble constant, $H_0 = 71 pm 20 mathrm{km s^{-1} Mpc^{-1}}$. Although with large uncertainty, we find that $H_0$ is only strongly degenerate with the B-band absolute magnitude ($M_B$) of SN Ia but almost independent on other nuisance parameters. Therefore the accuracy can be simultaneously improved by a tight constraint of $M_B$ through a cosmological and $H_0$ independent way. This method can be extended further to get more-literally non-local results of $H_0$ by using other Hubble diagrams at higher redshifts.
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