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تسجيل مستخدم جديدFormation of Double Compact Objects
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تأليف
V. Kalogera
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Current observations of double neutron stars provide us with a wealth of information that we can use to investigate their evolutionary history and the physical conditions of neutron star formation. Understanding this history and formation conditions further allow us to make theoretical predictions for the formation of other double compact objects with one or two black hole components and assess the detectability of such systems by ground-based gravitational-wave interferometers. In this paper we summarize our groups body of work in the past few years and we place our conclusions and current understanding in the framework of other work in this area of astrophysical research.
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We study the impact of different galaxy statistics and empirical metallicity scaling relations on the merging rates and on the properties of compact objects binaries. First, we analyze the similarities and differences of using the star formation rate
functions or the stellar mass functions as galaxy statistics for the computation of the cosmic star formation rate density. Then we investigate the effects of adopting the Fundamental Metallicity Relation or a classic Mass Metallicity Relation to assign metallicity to galaxies with given properties. We find that when the Fundamental Metallicity Relation is exploited, the bulk of the star formation occurs at relatively high metallicities even at high redshift; the opposite holds when the Mass Metallicity Relation is employed, since in this case the metallicity at which most of the star formation takes place strongly decreases with redshift. We discuss the various reasons and possible biases originating this discrepancy. Finally, we show the impact that these different astrophysical prescriptions have on the merging rates and on the properties of compact objects binaries; specifically, we present results for the redshift dependent merging rates and for the chirp mass and time delay distributions of the merging binaries.
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