111303184
A MODULAR CAVITY FOR MUON IONIZATION COOLING R&D ∗
A goal of the Muon Accelerator Program (MAP) is the development of an ionization cooling channel for muon beams. Ionization cooling channel designs call for the operation of high-gradient, normal-conducting RF cavities in multi-Tesla solenoidal magnetic fields. However, strong magnetic fields have been shown in some cases to limit the maximum achievable gradient in RF cavities. This gradient limit is characterized by RF breakdown and damage to the cavity surface. To study this issue, we have developed an experimental program based on a modular pillbox cavity operating at 805 MHz. The modular cavity design allows for the evaluation of different cavity geometries and materials ‐ such as beryllium ‐ which may ameliorate or circumvent RF breakdown triggers. Modular cavity componentsmayfurthermorebe preparedwith differentsurface treatments, suchas high-temperatureannealingor chemical polishing. This poster presents the design and fabrication status of the modular cavity, as well as plans for the experimental program.
126044349
The Study of a Li Lens System as a Final Cooler for a Muon Collider
117359670
Study of the backgrounds for the search for proton decay to 10^35 y at the wipp site with the lanndd detector
We briefly describe the LANNDD 70-kT liquid argon TPC proposal for the WIPP underground facility at Carlsbad, New Mexico. We, then, identify the key backgrounds for the search for p -> K+ nu_bar to 10^35 years lifetime. The most serious non-neutrino background is due to high-energy neutrons producing strange particles in the detector. We show that this can be reduced to an acceptable level by appropriate fiducial volume cuts.
11553576
Comments on noncommutative gauge theories
Abstract We study the gauge theories on noncommutative space. We employ the idea of the covariant position to understand the linear and angular momenta, the center of mass position, and to express all gauge invariant observables including the Wilson line. In addition, we utilize the universality of the U (1) gauge theory, which originates from the underlying matrix theory, to analyze various solitons on U ( N ) theories, like the unstable static vortex solutions in two dimensions and BPS dyonic fluxon solutions.
122069269
Ground state of high-density matter
Abstract It is shown that if an upper bound to the false vacuum energy of the electroweak Higgs potential is satisfied, the true ground state of high-density matter is not nuclear matter, or even strange-quark matter, but rather a non-topological soliton where the electroweak symmetry is exact and the fermions are massless. We examine this possibility in the standard SU(3) C ⊗ SU(2) L ⊗ U(1) Y model. The bound to the false vacuum energy is satisfied only for a narrow range of the Higgs boson masses in the minimal electroweak model (within a few eV of its minimum allowed value of 6.6 GeV), and a somewhat wider range for electroweak models with a non-minimal Higgs sector.
197511603
Super-Yang-Mills theories on $S^{4} \times \mathbb{R}$
6140839
QCD vacuum structure in strong magnetic fields
We study the response of the QCD vacuum to strong magnetic fields, using a potential model for the quark-antiquark interaction. We find that production of spin-polarized $u\ifmmode \bar{u}\else \={u}\fi{}$ pairs is energetically favorable for fields $Bg{B}_{\mathrm{crit}}\ensuremath{\sim}10 {\mathrm{GeV}}^{2}.$ We contrast the resulting $u\ifmmode \bar{u}\else \={u}\fi{}$ condensate with the quark condensate which is present at zero magnetic field, and we estimate the corresponding magnetization as a function of B.
118339519
5-dim superconformal index with enhanced En global symmetry
A bstractThe five-dimensional $ \mathcal{N}=1 $ supersymmetric gauge theory with Sp(N) gauge group and SO(2Nf) flavor symmetry describes the physics on N D4-branes with Nf D8-branes on top of a single O8 orientifold plane in Type I′ theory. This theory is known to be superconformal at the strong coupling limit with the enhanced global symmetry $ {E_{{N_f +1}}} $ for Nf ≤ 7. In this work we calculate the superconformal index on S1 × S4 for the Sp(1) gauge theory by the localization method and confirm such enhancement of the global symmetry at the superconformal limit for Nf ≤ 5 to a few leading orders in the chemical potential. Both perturbative and (anti)instanton contributions are present in this calculation. For Nf = 6, 7 cases some issues related the pole structure of the instanton calculation could not be resolved and here we could provide only some suggestive answer for the leading contributions to the index. For the Sp(N) case, similar issues related to the pole structure appear.