LEADER 02144nam 2200385 450 001 9910572180903321 005 20230517105145.0 035 $a(CKB)5860000000047692 035 $a(NjHacI)995860000000047692 035 $a(EXLCZ)995860000000047692 100 $a20230517d2021 uy 0 101 0 $aeng 135 $aur||||||||||| 181 $ctxt$2rdacontent 182 $cc$2rdamedia 183 $acr$2rdacarrier 200 10$aIsotopic fractionation study towards massive star-forming regions across the Galaxy /$fLaura Colzi 210 1$aFirenze, Italy :$cFirenze University Press,$d[2021] 210 4$dİ2021 215 $a1 online resource (226 pages) $cillustrations 225 1 $aPremio tesi di dottorato ;$vVolume 91 311 $a88-5518-381-8 320 $aIncludes bibliographical references. 330 $aOne of the most important tools to investigate the chemical history of our Galaxy and our own Solar System is to measure the isotopic fractionation of chemical elements. In the present study new astronomical observations devoted to the study of hydrogen and nitrogen fractionation (D/H and 14N/15N ratios) of molecules, towards massive star-forming regions in different evolutionary phases, have been presented. Moreover, a new detailed theoretical study of carbon fractionation, 12C/13C ratios, has been done. One of the main results was the confirmation that the 14N/15N ratio increases with the galactocentric distance, as predicted by stellar nucleosynthesis Galactic chemical evolution models. This work gives new important inputs on the understanding of local chemical processes that favor the production of molecules with different isotopes in star-forming regions. 410 0$aPremio Firenze University Press tesi di dottorato (Series) ;$vVolume 91. 606 $aStars$xFormation 615 0$aStars$xFormation. 676 $a523.88 700 $aColzi$b Laura$01349013 801 0$bNjHacI 801 1$bNjHacl 906 $aBOOK 912 $a9910572180903321 996 $aIsotopic fractionation study towards massive star-forming regions across the Galaxy$93086889 997 $aUNINA