The demand for underground labs for neutrino and rare event search
experiments has been increasing over the last few decades. Yemilab, constructed
in October 2022, is the first deep (∼1~km) underground lab dedicated to
science in Korea, where a large cylindrical cavern (D: 20~m, H: 20~m) was
excavated in addition to the main caverns and halls. The large cavern could be
utilized for a low background neutrino experiment by a liquid
scintillator-based detector (LSC) where a 2.26 kiloton LS target would be
filled. It's timely to have such a large but ultra-pure LS detector after the
shutdown of the Borexino experiment so that solar neutrinos can be measured
much more precisely. Interesting BSM physics searches can be also pursued with
this detector when it's combined with an electron linac, a proton cyclotron
(IsoDAR source), or a radioactive source. This article discusses the concept of
a candidate detector and the physics potential of a large liquid scintillator
detector.Comment: 63 pages, 36 figures, 8 table