55696095
Higher genus BMN correlators: factorization and recursion relations
We systematically study the factorization and recursion relations in higher genus correlation functions of BMN (Berenstein-Maldacena-Nastase) operators in free N=4 super Yang Mills theory. These properties were found in a previous paper by the author, and were conjectured to result from the correspondence with type IIB string theory on the infinitely curved pp-wave background, where the strings become effectively infinitely long. Here we push the calculations to higher genus, provide more clarifications and verifications of the factorization and recursion relations. Our calculations provide conjectural indirect tests of the AdS/CFT correspondence for multi-loop superstring amplitudes of stringy modes.
17031489
D-branes in Yang-Mills theory and emergent gauge symmetry
Four-dimensional supersymmetric SU(N) Yang-Mills theory on a sphere has highly charged baryon-like states built from anti-symmetric combinations of the adjoint scalars. We show that these states, which are equivalently described as holes in a free fermi sea of a reduced matrix model, are D-branes. Their excitations are stringlike and effectively realize Dirichlet and Neumann boundary conditions in various directions. The low energy brane dynamics should realize an emergent gauge theory that is local on a new space. We show that the Gauss' Law associated to this emergent gauge symmetry appears from combinatorial identities relating the stringy excitations. Although these excitations are not BPS, they can be near-BPS and we can hope to study them in perturbation theory. Accordingly, we show that the Chan-Paton factors expected for strings propagating on multiple branes arise dynamically, allowing the emergent gauge symmetry to be non-abelian.
119469474
Aspects of Supersymmetric Gauge Theory and String Theory
This thesis consists of two parts. In the first part we study some topics in $\mathcal{N}=1$ supersymmeric gauge theory and the relation to matrix models. We review the relevant non-perturbative techniques for computing effective superpotential, such as Seiberg-Witten curve. Then we review the proposal of Dijkgraaf and Vafa that relates the glueball superpotentials to the computation in matrix models. We then consider a case of multi-trace superpotential. We perform the perturbative computation of glueball superpotential in this case and explain the subtlety in identifying the glueball superfield. We also use these techniques to study phases of $\mathcal{N}=1$ gauge theory with flavors. In the second part we study topics in AdS/CFT correspondence and its plane wave limit. We review the plane wave geometry and BMN operators that corresponding to string modes. Then we study string interactions in the case of a highly curved plane wave background, and demonstrate the agreements between calculations of string interaction amplitudes in the two dual theories. Finally we study D3-brane giant gravitons and open string attached to them. Giant gravitons are non-perturbative objects that have very large R-charge.
18708486
Open/closed string duality for topological gravity with matter
The exact FZZT brane partition function for topological gravity with matter is computed using the dual two-matrix model. We show how the effective theory of open strings on a stack of FZZT branes is described by the generalized Kontsevich matrix integral, extending the earlier result for pure topological gravity. Using the well-known relation between the Kontsevich integral and a certain shift in the closed-string background, we conclude that these models exhibit open/closed string duality explicitly. Just as in pure topological gravity, the unphysical sheets of the classical FZZT moduli space are eliminated in the exact answer. Instead, they contribute small, nonperturbative corrections to the exact answer through Stokes' phenomenon.
6313413
Holomorphic anomaly in gauge theories and matrix models
We use the holomorphic anomaly equation to solve the gravitational corrections to Seiberg-Witten theory and a two-cut matrix model, which is related by the Dijkgraaf-Vafa conjecture to the topological B-model on a local Calabi-Yau manifold. In both cases we construct propagators that give a recursive solution in the genus modulo a holomorphic ambiguity. In the case of Seiberg-Witten theory the gravitational corrections can be calculated to all genus as quasimodular functions of Γ(2). In the matrix model we fix the holomorphic ambiguity up to genus two. The latter result establishes the Dijkgraaf-Vafa conjecture at that genus and yields a new method for solving the matrix model at fixed genus in closed form in terms of generalized hypergeometric functions.
16820034
Holomorphicity and modularity in Seiberg-Witten theories with matter
We calculate the gravitational corrections to the effective action of N=2 SU(2) Seiberg-Witten theory with matter using modularity, the holomorphic anomaly equation and expected behavior at the boundaries of the moduli space. As in pure gauge theory we show that the gap condition at the dyon singularities completely fixes the gravitational corrections. We discuss the behavior of the gravitational corrections at the conformal points. We compare our results with the recursive solution of the loop equation in the matrix model approach, which provides in addition open amplitudes.
55287941
AUTO-FILLING CRYOGENIC SYSTEM FOR SUPERCONDUCTING WIGGLER
In a cryogenic plant, in which a superconducting rf cavity is present, an independent automatic filling system provides liquid helium and liquid nitrogen to the superconducting wiggler. A PID controller, the kernel of the auto-filling system, controls the valves of the liquid helium and the liquid nitrogen to facilitate a stable and precise auto-filling process. This work presents the control algorithm for the pre-cooling mode and normal auto-filling mode and presents cryogenic testing results.
119428187
Shower Spectrum and Detection of tau from Earth Skimming Neutrinos
A realistic Monte-Carlo simulation code is developed to study the shower spectrum initiated by decay of tau leptons, which come from charged current interaction inside the Earth. AGN and GZK neutrino fluxes are used to simulate the shower spectrum.
120445064
Superconducting wiggler with semi-cold beam duct at Taiwan light source
Abstract A 3.2 T superconducting wiggler with a periodic length of 6 cm and 32 poles was designed and fabricated as an X-ray source. The beam duct of this magnet is a semi-cold, ultra-high vacuum chamber that consists of an aluminum and stainless steel taper. The number of poles in this magnet design is even, to minimize the integral strengths of the multipole components. Two measurement systems—involving room-temperature and cryogenic Hall probes—were set up to measure the field of the superconducting wiggler. A cryogenic plant that supplied liquid helium and nitrogen to the superconducting wiggler has already been established. The performance of magnet construction is good and the commissioning of the superconducting wiggler in the storage ring has been successful. No trim coil compensation on the magnet is required to adjust the electron beam orbit. Furthermore, the electron beams exhibit no loss and remain highly stable after the superconducting wiggler has been quenched.
120451450
SHINIE: Simulation of High Energy Neutrinos Interacting with the Earth
SHINIE is acronym for Simulation of High-energy Neutrinos Interacting with the Earth, which is a Monte-Carlo simulation code for the interactions and propagations of neutrinos and leptons inside the Earth at energy greater than 10 14 eV. This code can be used for underground or above-ground neutrino telescopes. Since 2004, we had made several major updates, which include stochastic energy loss for τ and μ , modification for underground detector, addition of ν μ , ν e , μ , and electron, and a new material salt for simulation of underground salt dome neutrino detector. Details of this code are described here. A benchmark test of tau lepton flux passing through 100 km of standard rock are performed and concluded that all processes behave properly and consistent with previous versions.
15862525
Physics Results From Alpha Magnetic Spectrometer 1998 Shuttle Flight
The Alpha Magnetic Spectrometer (AMS) is a particle detector designed to detect antimatter. During the 10-day test flight on the space shuttle in June 1998, AMS detected $10^8$ events. Upon analysis, no antimatter was found and the antimatter limit was reduced to $1.1\times10^{-6}$. The proton spectrum shows some differences with the cosmic ray flux used in atmospheric neutrino simulation. A large amount of protons, positrons, and electrons were found below the geomagnetic rigidity cutoff. The energy of these particles are as high as several GeV, one order of magnitude higher than any previously measured energy in radiation belts. These particles also exhibit many interesting features. This paper reviews the results in the four published papers of the AMS collaboration and provides explanation for some features of the albedo particles.