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Kim, S.-H.

Publications and source records attributed to Kim, S.-H..

Status of SNS Proton Power Upgrade SRF Cavities Production Qualification

The Pro­ton Power Up­grade pro­ject at Oak Ridge Na­tional Lab’s Spal­la­tion Neu­tron Source (SNS PPU) cur­rently being con­structed will dou­ble the pro­ton beam power from 1.4 to 2.8 MW by adding 7 ad­di­tional cry­omod­ules, each con­tains four six-cell high beta (\beta = 0.81) su­per­con­duct­ing radio fre­quency cav­i­ties. The cav­i­ties were built by Re­search In­stru­ments, Ger­many, with all the cav­ity pro­cess­ing done at the ven­dor site, in­clud­ing elec­trop­o­l­ish­ing as the final ac­tive chem­istry step. All 28 cav­i­ties needed for 7 cry­omod­ules were de­liv­ered to Jef­fer­son Lab, ready to be tested. The cryo­genic RF qual­i­fi­ca­tions and he­lium ves­sel weld­ing were done at Jef­fer­son Lab. The per­for­mance largely ex­ceed the re­quire­ments, and greatly ex­ceeded the per­for­mance of the orig­i­nal SNS cav­ity pro­duc­tion se­ries. Here, we pre­sent the sum­mary of RF test on pro­duc­tion cav­i­ties to this date.

Dhakal, P.↗

Applications of squeezed states: Bogoliubov transformations and wavelets to the statistical mechanics of water and its bubbles

The squeezed states or Bogoliubov transformations and wavelets are applied to two problems in nonrelativistic statistical mechanics: the dielectric response of liquid water, epsilon(q-vector,w), and the bubble formation in water during insonnification. The wavelets are special phase-space windows which cover the domain and range of L(exp 1) intersection of L(exp 2) of classical causal, finite energy solutions. The multiresolution of discrete wavelets in phase space gives a decomposition into regions of time and scales of frequency thereby allowing the renormalization group to be applied to new systems in addition to the tired 'usual suspects' of the Ising models and lattice gasses. The Bogoliubov transformation: squeeze transformation is applied to the dipolaron collective mode in water and to the gas produced by the explosive cavitation process in bubble formation.

Defacio, Brian↗