?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adissertation&rft.aulast=Zhang&rft.aufirst=Zhong&rft.au=Zhang%2C+Zhong&rft.date=28+January+2025&rft.tpages=190&rft.title=Probing+Heavy+Neutral+Leptons+in+Direct+Searches%2C+Double+Beta+Decay+and+Cosmology&rft.inst=UCL+(University+College+London)&rft.degree=Doctoral