Research

The group is established as part of the Joint Consortium for Fundamental Physics by three universities in Hong Kong – HKU, CUHK and HKUST, through which we participate in international collaborations on big science.

Under this umbrella of the joint consortium, a Hong Kong cluster formally joined the ATLAS experiment at the Large Hadron Collider in June 2014. One of the missions led by the Hong Kong cluster is to build up a Tier-2 (and Tier-3) computing center in Hong Kong, which is expected to play an important role in serving both the LHC physics community and the local scientific and engineering community. The center is designed to have 1000 processing cores and 1 petabytes of disk space. The laboratory is the part of the Tier-2 (and Tier-3) computing center for analyzing data collected by the ATLAS experiment at the LHC in CERN. The lab has access to the Worldwide LHC Computing Grid, which is the world's largest computing grid.

Prof. Tu’s research is on experimental particle physics where the goal is to understand fundamental particles and their interactions. The startup of the Large Hadron Collider (LHC), the world's largest and highest energy particle accelerator, in 2009 opened up a new era at the high energy frontier. The unexplored energy domain of the LHC provides unique opportunities to answer fundamental questions in particle physics, such as the cause of electroweak symmetry breaking, the mass origin of particles in the Standard Model, the generation of baryon asymmetry in the Universe and the properties of dark matter. Exploring these topics could dramatically improve our understanding of nature. The recent observation of the Higgs boson in the ATLAS and the CMS experiments represents one such success. In view of this remarkable progress, the next several years will be a critical and significant period for the field development of the HEP.

With strong support from the member institutions of the Hong Kong Joint Consortium for Fundamental Physics and the Research Grants Council, Hong Kong is now participating in the LHC ATLAS experiment. The Hong Kong particle physics group is involved in several projects including searching for supersymmetric particles, and searching for beyond Standard Model heavy gauge bosons. The group is also responsible for software and hardware upgrades: software development for muon reconstruction and Phase I Phase II muon detector electronics upgrade.

Prof. Lee’s group is dedicated to the studies of the nuclear shell structure evolution and the nucleon correlations in nuclei. The experimental techniques include direct reactions, in-beam gamma spectroscopy and beta-decay spectroscopy. The state-of-the-art gamma-ray detector array and charged particle detector array will be constructed at the University of Hong Kong in collaboration with RIKEN (Japan) and IPN-Orsay (France). Both arrays are portable with fully integrable capability to the detection systems at the present facility RIKEN (Japan) and in the future-upgraded accelerated-based laboratories worldwide such as NSCL/FRIB (United States) and Spiral2 (France).

Prof. Lee studies cutting-edge Gamma-ray detector array and charged particle detector array, based on international collaborations, will be developed to achieve high-efficient and high-resolution measurements for the studies of nuclear structure. The arrays are designed for easy configuration and full integration with other devices to meet the detection requirements of specific major experiments, which will be performed in the Radioactive-Isotope Beams facilities worldwide such as RIKEN (Japan) and NSCL/FRIB (United States).

Prof. J.H.C. Lee

1. “Low-Lying Structure of ⁵⁰Ar and the N=32  Subshell Closure” D. Steppenbeck, S. Takeuchi, N. Aoi, P. Doornenbal, M. Matsushita, H. Wang, Y. Utsuno, H. Baba, S. Go, J.H.C. Lee, K. Matsui, S. Michimasa, T. Motobayashi, D. Nishimura, T. Otsuka, H. Sakurai, Y. Shiga, N. Shimizu, P.-A. Söderström, T. Sumikama, R. Taniuchi, J. J. Valiente-Dobón, and K. Yoneda, Phys. Rev. Lett. 114, 252501 (2015)
2. "Neutron spectroscopic factors of ⁵⁵Ni hole-states from (p,d) transfer reactions", A. Sanetullaev, M.B. Tsang, W.G. Lynch, J.H.C. Lee, D.Bazin, D.Coupland, V.Henzl, D.Henzlova, M.Kilburn, A.M.Rogers, Z.Y.Sun, M.Youngs, R.J.Charity, L.G.Sobotka, M.Famiano, S. Hudan, D. Shapira, W.A. Peters, C. Barbieri, M. Hjorth-Jensen, M. Horoi, T. Otsuka, T. Suzuki and Y. Utsuno,  Physics Letters B, 736, 137 (2014)
3. "Evidence for a new nuclear 'magic' number from the structure of ⁵⁴Ca", D. Steppenbeck, S. Takeuchi, N. Aoi, P. Doornenbal, M. Matsushita, H. Wang, H. Baba, N. Fukuda, S. Go, M. Honma, J. Lee, K. Matsui, S. Michimasa, T. Motobayashi, D. Nishimura, T. Otsuka, H. Sakurai, Y. Shiga, P.-A. Soderstrom, T. Sumikama, H. Suzuki, R. Taniuchi, Y. Utsuno, J.J.Valiente-Dobon, and K. Yoneda, Nature, 502, 207 (2013)
4. "In-Beam γ-Ray Spectroscopy of ^{34, 36,38}Mg: Merging the N=20 and N=28 Shell Quenching", P. Doornenbal, H. Scheit, N. Aoi, S. Takeuchi, K. Li, M. Matsushita, D. Steppenbeck, H. Wang, H. Baba, E. Ideguchi, N. Kobayashi, Y. Kondo, G. Lee, J.H.C. Lee, S. Michimasa, T. Motobayashi, H. Sakurai, M. Takechi and Y. Togano, Phys. Rev. Lett., 111, 212502 (2013)
5. "Neutron-hole states in ⁴⁵Ar from ¹H(⁴⁶Ar,d)⁴⁵Ar reactions", F. Lu. J.H.C. Lee, M.B. Tsang, D. Bazin, D. Coupland, V. Henzl, D. Henzlova, M. Kiburn, W.G. Lynch. A.M. Rogers. A. Sanetullaev, Z.Y Sun, M. Youngs, R.J. Charity, L.G. Sobotka, M. Famiano, S. Hudan, M. Horoi, Y. Ye, Phys. Rev. C, 88, 017604 (2013)
6. "A Laser Based Alignment System (LBAS) for Nuclear Physics Experiments", A.M. Rogers, J.H.C. Lee, B.E. Netta, M.S. Wallace, W.G. Lynch, H.K. Cheung, L. El-Mogaber, R. Fontus, T.K.Ghosh, V. Henzl, D. Henzlova, M. Kilburn, D.J. Oostdyk, D. Sanderson, Z.Y. Sun, M.B. Tsang, Nucl. Instrum. Meth. A, 707, 64 (2013)
7. "Well-developed deformation in ⁴²Si", S. Takeuchi, M. Matsushita, N. Aoi, P. Doornenbal,K. Li, T. Motobayashi, H. Scheit, D. Steppenbeck, H. Wang, H. Baba, D. Bazin, L. C`aceres, H. Crawford, P. Fallon, R. Gernhauser, J. Gibelin, S. Go, S. Grevy, C. Hinke, C. R. Hoffman, R. Hughes,E. Ideguchi, D. Jenkins, N. Kobayashi, Y. Kondo, R. Krucken, T. Le Bleis, J.H.C. Lee, G. Lee, A. Matta, S. Michimasa, T. Nakamura, S. Ota, M. Petri, T. Sako, H. Sakurai, S. Shimoura, K. Steiger, K. Takahashi, M. Takechi, Y. Togano, R. Winkler, and K. Yoneda, Phys. Rev. Lett., 109, 182501 (2012)
8. "Neutron spectroscopic factors of ³⁴Ar and ⁴⁶Ar", J.H.C. Lee, M.B. Tsang, D. Bazin, D. Coupland, V. Henzl, D. Henzlova, M. Kilburn, W.G. Lynch, A. Rogers, A. Sanetullaev, A. Signoracci, Z.Y. Sun, M. Youngs, K.Y. Chae, R.J. Charity, H.K. Cheung, M. Famiano, S. Hudan, P. O’Malley, W.A. Peters, K. Schmitt, D. Shapira, L.G. Sobotka, Phys. Rev. C, 83, 014606 (2011)
9. "Neutron-proton asymmetry dependence of spectroscopic factors in Ar isotopes", J.H.C. Lee, M.B. Tsang, D. Bazin, D. Coupland, V. Henzl, D. Henzlova, M. Kilburn, W.G. Lynch, A. Rogers, A. Sanetullaev, A. Signoracci, Z.Y. Sun, M. Youngs, K.Y. Chae, R.J. Charity, H.K. Cheung, M. Famiano, S. Hudan, P. O’Malley, W.A. Peters, K. Schmitt, D. Shapira, L.G. Sobotka, Phys. Rev. Lett., 104, 112701 (2010)

Prof. Y.J. Tu

1. "Search for top quark decays t → Hq with 36 f b⁻¹ of pp collision data at sqrt (s ) = 13 TeV with the ATLAS detector”, Y.J. Tu, with ATLAS Collaboration, Journal of High Energy Physics 05 (2019) 123
2. "Search for four-top-quark production in the single-lepton and opposite-sign dilepton final states in pp collisions at sqrt( s ) = 13 TeV with the ATLAS detector ”, Y.J. Tu, with ATLAS Collaborators, Phys. Rev. D 99, 052009
3. "Search for pair production of up-type vector like quarks and for four-top-quark events in final states with multiple b-jets with the ATLAS detector”, Y.J. Tu, with ATLAS Collaborators, Journal of High Energy Physics 07 (2018) 089
4. "Search for new phenomena in tt¯ final states with additional heavy-flavour jets in pp collisions at sqrt( s ) = 13 TeV with the ATLAS detector”, Y.J. Tu, with ATLAS Collaborators, ATLAS-CONF-2016-104.
5. "Measurements of the tt; charge asymmetry using the dilepton decay channel in pp collisions at √s = 7 TeV", Y.J. Tu, with CMS Collaborators, Journal of High Energy Physics, 4, 191 (2014)
6. "Measurements of tt Spin Correlations and Top-Quark Polarization Using Dilepton Final States in pp Collisions at √s =7  TeV", Y.J. Tu, with CMS Collaborators, Phys. Rev. Lett., 112, 182001 (2014)
7. "Search for heavy, top-like quark pair production in the dilepton final state in pp collisions at √s =7  TeV", Y.J. Tu, with CMS Collaborators, Phys. Lett. B, 716, pp103-121 (2012)
8. "Search for R-Parity Violating Decays of Sneutrinos to eμ, μτ, and eτ Pairs in pp; Collisions at √s =1.96  TeV", Y.J. Tu, with CDF Collaborators, Phys. Rev. Lett., 105, 191801 (2010)