The Jiangmen Underground Neutrino Observatory (JUNO), a 20 kton multi-purpose
underground liquid scintillator detector, was proposed with the determination
of the neutrino mass hierarchy as a primary physics goal. It is also capable of
observing neutrinos from terrestrial and extra-terrestrial sources, including
supernova burst neutrinos, diffuse supernova neutrino background, geoneutrinos,
atmospheric neutrinos, solar neutrinos, as well as exotic searches such as
nucleon decays, dark matter, sterile neutrinos, etc. We present the physics
motivations and the anticipated performance of the JUNO detector for various
proposed measurements. By detecting reactor antineutrinos from two power plants
at 53-km distance, JUNO will determine the neutrino mass hierarchy at a 3-4
sigma significance with six years of running. The measurement of antineutrino
spectrum will also lead to the precise determination of three out of the six
oscillation parameters to an accuracy of better than 1\%. Neutrino burst from a
typical core-collapse supernova at 10 kpc would lead to ~5000
inverse-beta-decay events and ~2000 all-flavor neutrino-proton elastic
scattering events in JUNO. Detection of DSNB would provide valuable information
on the cosmic star-formation rate and the average core-collapsed neutrino
energy spectrum. Geo-neutrinos can be detected in JUNO with a rate of ~400
events per year, significantly improving the statistics of existing geoneutrino
samples. The JUNO detector is sensitive to several exotic searches, e.g. proton
decay via the p→K++νˉ decay channel. The JUNO detector will provide
a unique facility to address many outstanding crucial questions in particle and
astrophysics. It holds the great potential for further advancing our quest to
understanding the fundamental properties of neutrinos, one of the building
blocks of our Universe
