SooKyung Choi is a South Korean particle physicist at Gyeongsang National University. She is part of the Belle experiment and was the first to observe the

X(3872) The X(3872) is an exotic meson candidate with a mass of 3871.68 MeV/c2 which does not fit into the quark model because of its quantum numbers. It was first discovered in 2003 by the Belle experiment in Japan and later confirmed by several other exp ...

meson in 2003. She won the 2017 Ho-Am Prize in Science.

Early life and education

Choi studied physics at the

Kyungpook National University Kyungpook National University (경북대학교, abbreviated as KNU or Kyungdae, 경대) is one of ten Flagship Korean National Universities representing Daegu Metropolitan City and Gyeongbuk Province in South Korea. It is located in the Dae ...

, graduating in 1979 with a Bachelor's degree and 1993 with a PhD. Her supervisors were Dongchul Son and C. Joo. After graduating, Choi joined

Seoul National University Seoul National University (SNU; ) is a national public research university located in Seoul, South Korea. Founded in 1946, Seoul National University is largely considered the most prestigious university in South Korea; it is one of the three "S ...

, working on Møller and

Bhabha scattering In quantum electrodynamics, Bhabha scattering is the electron-positron scattering process: ::e^+ e^- \rightarrow e^+ e^- There are two leading-order Feynman diagrams contributing to this interaction: an annihilation process and a scattering proc ...

. She was appointed Professor at Gyeongsang National University, where she worked with the

High Energy Accelerator Research Organization , known as KEK, is a Japanese organization whose purpose is to operate the largest particle physics laboratory in Japan, situated in Tsukuba, Ibaraki Prefecture, Ibaraki prefecture. It was established in 1997. The term "KEK" is also used to refe ...

(KEK).

Career

Choi's work mainly concerns

CP violation In particle physics, CP violation is a violation of CP-symmetry (or charge conjugation parity symmetry): the combination of C-symmetry (charge symmetry) and P-symmetry ( parity symmetry). CP-symmetry states that the laws of physics should be the ...

and decays of the B meson. Choi worked on the Belle experiment, where she identified several new types of fundamental particles. The first results from Belle came in 2002, finding large cross-sections for the e⁺e₋continuum. In 2003 she discovered the

meson; a new kind of heavy particle, which does not fit the quantum model as it was made up of four

quark A quark () is a type of elementary particle and a fundamental constituent of matter. Quarks combine to form composite particles called hadrons, the most stable of which are protons and neutrons, the components of atomic nuclei. All commonly o ...

s. Choi predicted the

particle could be a

charmonium In particle physics, quarkonium (from quark and -onium, pl. quarkonia) is a flavorless meson whose constituents are a heavy quark and its own antiquark, making it both a neutral particle and its own antiparticle. Light quarks Light quarks ( up ...

state or a DD* hadronic molecule. The work was confirmed by a team at the Fermi National Accelerator Laboratory. Choi went on to discover the Y(3940), the

Zc(3900) The Zc(3900) is a hadron, a type of subatomic particle made of quarks, believed to be the first tetraquark that has been observed experimentally. The discovery was made in 2013 by two independent research groups: one using the BES III detector a ...

and

Z(4430) Z(4430) is a mesonic resonance discovered by the Belle experiment. It has a mass of . The resonant nature of the peak has been confirmed by the LHCb experiment with a significance of at least 13.9 σ. The particle is charged and is thought ...

particles, which proved that particles can exist in a range of forms. Choi studied the decays of these extensively. She was involved with the study of other

states; using the ϒ(4S) and ϒ(5S) resonances at the Belle detector. Choi has collaborated with the BES III experiment, which studied

center of mass In physics, the center of mass of a distribution of mass in space (sometimes referred to as the balance point) is the unique point where the weighted relative position of the distributed mass sums to zero. This is the point to which a force may ...

energies between 2.9 and 4.42 GeV. The BES III experiment identified new

states with non-zero electric charge.

was first confirmed at the Belle experiment and would go on to win the 2008

Nobel Prize in Physics ) , image = Nobel Prize.png , alt = A golden medallion with an embossed image of a bearded man facing left in profile. To the left of the man is the text "ALFR•" then "NOBEL", and on the right, the text (smaller) "NAT•" then " ...

. The experiments stopped operation in June 2010. Choi is part of the

Belle II experiment The BelleII experiment is a particle physics experiment designed to study the properties of B mesons (heavy particles containing a beauty quark) and other particles. BelleII is the successor to the Belle experiment, and commissioned at the Super ...

, which collected their first collisions in 2018. She served on the advisory board of the

International Conference on High Energy Physics ICHEP or International Conference on High Energy Physics is one of the most prestigious international scientific conferences in the field of particle physics, bringing together leading theorists and experimentalists of the world. It was first held ...

Seoul Seoul (; ; ), officially known as the Seoul Special City, is the capital and largest metropolis of South Korea.Before 1972, Seoul was the ''de jure'' capital of the Democratic People's Republic of Korea (North Korea) as stated iArticle 103 ...

in July 2018. In 2017 Choi won the Ho-Am Prize in Science.

References

{{DEFAULTSORT:Choi, Sookyung South Korean physicists South Korean women scientists Academic staff of Seoul National University Kyungpook National University alumni Particle physicists Living people Year of birth missing (living people) Recipients of the Ho-Am Prize in Science