A5021761456- Particle Accelerators and Free-Electron Lasers
- Particle accelerators and beam dynamics
- Superconducting Materials and Applications
- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Quantum Chromodynamics and Particle Interactions
- Particle Detector Development and Performance
- Laser-Plasma Interactions and Diagnostics
- Advanced Data Storage Technologies
- Advanced NMR Techniques and Applications
- Cold Atom Physics and Bose-Einstein Condensates
- Radiative Heat Transfer Studies
- Nuclear physics research studies
- Astrophysics and Cosmic Phenomena
- Spectral Theory in Mathematical Physics
- Atomic and Subatomic Physics Research
- Meteorological Phenomena and Simulations
- 3D IC and TSV technologies
- Experimental and Theoretical Physics Studies
- Heat Transfer and Boiling Studies
- Spacecraft and Cryogenic Technologies
- VLSI and FPGA Design Techniques
- Spacecraft Design and Technology
Northwest Normal University
2024
Institute of Theoretical Physics
2024
Brookhaven National Laboratory
2011-2022
Head-on beam-beam compensation has been implemented in the Relativistic Heavy Ion Collider order to increase luminosity delivered experiments. We discuss principle of combining a lattice for resonance driving term and an electron lens tune spread compensation. describe technology its operational use. To date, scheme approximately doubled peak average luminosities.
Inspired by the recently observed resonance states <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:msubsup><a:mi>P</a:mi><a:mrow><a:mi>ψ</a:mi><a:mi>s</a:mi></a:mrow><a:mi mathvariant="normal">Λ</a:mi></a:msubsup><a:mo stretchy="false">(</a:mo><a:mn>4338</a:mn><a:msup><a:mo stretchy="false">)</a:mo><a:mn>0</a:mn></a:msup></a:math> and <f:math xmlns:f="http://www.w3.org/1998/Math/MathML"...
In polarized proton collision experiments, it is highly advantageous to flip the spin of each bunch protons during stores reduce systematic errors. Experiments done at energies less than 2 GeV have demonstrated a spin-flip efficiency over 99%. At high energy colliders with Siberian snakes, single magnet flipper does not work because large tune spread and generation multiple, overlapping resonances. A more sophisticated flipper, constructed nine-dipole magnets, was used in BNL Relativistic...
A hollow electron beam has been proposed as an active control tool to remove the halo from high-energy, high-current hadron or ion machines (such High-Luminosity Large Hadron Collider). To study removal rate and assess effect on core, one of two lenses in Relativistic Heavy Ion Collider was changed a Gaussian profile profile. We describe design verification parameters well methods minimize distortions, which can result emittance increase. The alignment with by using backscattered detector...
The Low Energy Relativistic Heavy Ion Collider (RHIC) Electron Cooler (LEReC) is the world's first electron cooler using rf-accelerated bunches. Recently, cooling of gold ion beams in RHIC by 1.6 and 2.0 MeV electrons was successfully achieved. Along with velocity spread alignment beam, space-charge force between ions also plays an important role process. In order to investigate dynamics bunched provide guidance for LEReC operation, a simulation code developed, which includes nonmagnetized...
In light of the recently observed resonance states $P_{\psi s}^{\Lambda}(4338)^0$ and $P_{cs}(4459)^0$ by LHCb Collaboration in $J/\psi\Lambda$ decay channel, we perform a systematical study all possible hidden-heavy pentaquarks with strangeness $S=0,-1,-2,-3$, unified framework MIT bag model. The color-spin wavefunctions presented terms Young-Yamanouchi bases transformed into baryon-meson couplings, are utilized to calculate masses, magnetic moments ratios partial widths. With numerical...
The world's first electron cooling based on the rf acceleration of bunches was experimentally demonstrated at Low Energy RHIC Electron Cooler (LEReC) Brookhaven National Laboratory. critical step in obtaining Au ions collider with this new approach matching and ion relativistic $\ensuremath{\gamma}$-factors a relative error less than $5\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$. Since beam kinetic energy just 1.6 MeV, it required to set absolute electrons an accuracy better...
This Letter reports the first spin tune measurement at high energies (24 and 255 GeV) with a driven coherent motion. To maintain polarization in polarized proton collider, it is important to know of beam, which defined as number full precessions per revolution. A nine-magnet flipper has demonstrated spin-flip efficiency presence two Siberian snakes [H. Huang et al., Phys. Rev. Lett. 120, 264804 (2018).10.1103/PhysRevLett.120.264804]. The drives resonance given frequency (or tune) strength....
Persistent currents in superconducting magnet introduce magnetic errors especially at low operating fields. In addition, their decay causes field variations and therefore drifts of the beam orbits, tunes, chromaticities. To reduce suppress variations, a new cycle was proposed for low-energy operation Relativistic Heavy Ion Collider (RHIC). cycle, current oscillates around nominal with diminishing amplitude few times before it settles. The has been demonstrated experimentally to significantly...
In this paper, our main focus is on calculation the mass and partial decay width ratios of triply heavy pentaquark state \(QQQn\bar{n}(Q=b,c)\). By MIT bag model, we conduct fitting variational calculations to obtain spectrum \(QQQn\bar{n}\) system. excluding scattering states based color-spin wave functions corresponding obtained masses, derive for compact their potential products. analyzing ratio different channels, can get modes studied system, specific characteristics channels under...
Abstract In this study, we analyzed masses and decays of triply-heavy pentaquarks in the unified MIT bag model. We construct color-spin wave functions use numerical variational method to compute all ground-state these systems. By excluding scattering states configuration spsce, computed decay width ratios each channel relative maximum for compact pentaquark states, obtaining main modes
The spin structure of the proton is one unsolved problems in physics. Relativistic Heavy Ion Collider (RHIC) Spin Physics Program has been conducting research to investigate by colliding high energy polarized beams. Maintaining polarization while achieving luminosity critical for this program. Two challenges related program are maintain during flipping, a process designed reduce systematic errors asymmetry measurements, and beam acceleration from low source collision experiment. Recently,...
The first electron cooling with rf-accelerated bunches was recently demonstrated at the low energy RHIC cooler (LEReC) BNL. Successful requires that electrons in section have a small angular spread and are well aligned respect to copropagating ions. LEReC puts into practice nonmagnetized of ions Lorentz factors $\ensuremath{\gamma}=4.1$ 4.9. Hence, unlike previous coolers, which transverse dynamics is constrained by longitudinal solenoid fields, ion-electron focusing steering strongly...
The Beam Energy Scan phase II (BES-II), performed in the Relativistic Heavy Ion Collider (RHIC) from 2019 to 2021, explored transition between quark-gluon plasma and hadronic gas. BES-II exceeded goal of a fourfold increase average luminosity over that achieved during I (BES-I), at five gold beam energies: 9.8, 7.3, 5.75, 4.59, $3.85\text{ }\text{ }\mathrm{GeV}/\mathrm{nucleon}$. This was accomplished by addressing several dynamics effects, including intrabeam scattering, beam-beam, space...