118380888
Direct integration for general $\Omega$ backgrounds
We extend the direct integration method of the holomorphic anomaly equations to general Ω backgrounds ǫ1 6= −ǫ2 for pure SU(2) N=2 Super-Yang-Mills theory and topological string theory on non-compact Calabi-Yau threefolds. We find that an extension of the holomorphic anomaly equation, modularity and boundary conditions provided by the perturbative terms as well as by the gap condition at the conifold are sufficient to solve the generalized theory in the above cases. In particular we use the method to solve the topological string for the general Ω backgrounds on non-compact toric Calabi-Yau spaces. The conifold boundary condition follows from that the N=2 Schwinger-Loop calculation with BPS states coupled to a self-dual and an anti-self-dual field strength. We calculate such BPS states also for the decompactification limit of Calabi-Yau spaces with regular K3 fibrations and half K3s embedded in Calabi-Yau backgrounds. minxin.huang@ipmu.jp aklemm@th.physik.uni-bonn.de
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.
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.
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.
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.
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.
24431504
Magnet block arrangements for the APPLE-II elliptically polarized undulator
The uniform field region (magnetic field roll-off) of the distributions of horizontal and vertical fields in the elliptically polarized undulator (EPU) of the APPLE-II structure is too short. Hence magnet block arrangements such as (1) the magnet block magnetized with a tilt angle, (2) a step shim of thickness 0.5 mm placed at the magnet edge, and (3) shortening the transverse dimension of the magnet block have been investigated to enlarge the uniform field region. The advantages and disadvantages of these block arrangements are discussed. The pure and hybrid structure of the EPU with an optimized end-pole design and the merit of flux as a function of varied phase have also been studied.
121057168
Construction and performance of the elliptical polarization undulator EPU5.6 in SRRC
A 132 pole elliptically polarizing undulator (EPU5.6) with magnetic period of 5.6 cm for production of brilliant and soft X-rays has been constructed and performed the field measurement at synchrotron radiation research center (SRRC). The "Apple-II" type device was selected for this EPU5.6 structure. The key factors in the construction and assembly process stage are described. In addition, the shimming algorithm for the magnetic field adjustment, the performance of the mechanical structure, magnetic field distribution without the field shimming are presented in this paper. Meanwhile, the control performance is also discussed.
125382211
DESIGN OF AN IN ACHROMATIC SUPERCONDUCTING WIGGLER AT NSRRC
A 15-pole superconducting wiggler with period length of 6.1 cm is designed for National Synchrotron Research Center (NSRRC) in Taiwan. The compact superconducting wiggler will be installed near the second bending magnet of the triple bend achromatic section in the 1.5 GeV storage ring. This wiggler magnet with maximum peak field of 3.1 T at pole gap width of 19 mm is operated in 4.2 K liquid helium vessel. A 5-pole prototype magnet is tested and measured to verify the magnetic field performance in the testing dewar. The cryogenic considerations and thermal analysis in the wiggler magnet and the 77 K cold bore beam vacuum chamber are also presented in this work.
122312631
Design and initial performance of the Askaryan Radio Array prototype EeV neutrino detector at the South Pole
Abstract We report on studies of the viability and sensitivity of the Askaryan Radio Array (ARA), a new initiative to develop a Teraton-scale ultra-high energy neutrino detector in deep, radio-transparent ice near Amundsen-Scott station at the South Pole. An initial prototype ARA detector system was installed in January 2011, and has been operating continuously since then. We describe measurements of the background radio noise levels, the radio clarity of the ice, and the estimated sensitivity of the planned ARA array given these results, based on the first five months of operation. Anthropogenic radio interference in the vicinity of the South Pole currently leads to a few-percent loss of data, but no overall effect on the background noise levels, which are dominated by the thermal noise floor of the cold polar ice, and galactic noise at lower frequencies. We have also successfully detected signals originating from a 2.5 km deep impulse generator at a distance of over 3 km from our prototype detector, confirming prior estimates of kilometer-scale attenuation lengths for cold polar ice. These are also the first such measurements for propagation over such large slant distances in ice. Based on these data, ARA-37, the ∼200 km 2 array now in its initial construction phase, will achieve the highest sensitivity of any planned or existing neutrino detector in the 10 16 –10 19  eV energy range.