118460136
The Crepant Transformation Conjecture for Toric Complete Intersections
Abstract Let X and Y be K -equivalent toric Deligne–Mumford stacks related by a single toric wall-crossing. We prove the Crepant Transformation Conjecture in this case, fully-equivariantly and in genus zero. That is, we show that the equivariant quantum connections for X and Y become gauge-equivalent after analytic continuation in quantum parameters. Furthermore we identify the gauge transformation involved, which can be thought of as a linear symplectomorphism between the Givental spaces for X and Y , with a Fourier–Mukai transformation between the K -groups of X and Y , via an equivariant version of the Gamma-integral structure on quantum cohomology. We prove similar results for toric complete intersections. We impose only very weak geometric hypotheses on X and Y : they can be non-compact, for example, and need not be weak Fano or have Gorenstein coarse moduli space. Our main tools are the Mirror Theorems for toric Deligne–Mumford stacks and toric complete intersections, and the Mellin–Barnes method for analytic continuation of hypergeometric functions.
4807800
Fixing the quantum three-point function
A bstractWe propose a new method for the computation of quantum three-point functions for operators in $ \mathfrak{s}\mathfrak{u} $(2) sectors of $ \mathcal{N} $ = 4 super Yang-Mills theory. The method is based on the existence of a unitary transformation relating inhomogeneous and long-range spin chains. This transformation can be traced back to a combination of boost operators and an inhomogeneous version of Baxter’s corner transfer matrix. We reproduce the existing results for the one-loop structure constants in a simplified form and indicate how to use the method at higher loop orders. Then we evaluate the one-loop structure constants in the quasiclassical limit and compare them with the recent strong coupling computation.
122386462
RF undulator for compact X-ray SASE source of variable wavelength
A room-temperature RF undulator, fed by Ka-band radiation and intended to produce ∼1 nm wavelength radiation using moderate energy electrons, is considered. The necessary electron bunches with energy 0.2-1 GeV could be produced by petawatt laser pulses injected into plasma bubbles.
209982477
2HDM and Enhanced Rates in $\gamma\gamma$ Channel
119395913
Proof of principle for a high sensitivity search for the electric dipole moment of the electron using the metastable a(1)[^3\Sigma^+] state of PbO
The metastable a(1)[^3\Sigma^+] state of PbO has been suggested as a suitable system in which to search for the electric dipole moment (EDM) of the electron. We report here the development of experimental techniques allowing high-sensitivity measurements of Zeeman and Stark effects in this system, similar to those required for an EDM search. We observe Zeeman quantum beats in fluorescence from a vapor cell, with shot-noise limited extraction of the quantum beat frequencies, high counting rates, and long coherence times. We argue that improvement in sensitvity to the electron EDM by at least two orders of magnitude appears possible using these techniques.
119226921
Two-Higgs-doublet models and enhanced rates for a 125 GeV Higgs
A bstractWe examine the level of enhancement that can be achieved in the ZZ and γγ channels for a two-Higgs-doublet model Higgs boson (either the light h or the heavy H) with mass near 125 GeV after imposing all constraints from LEP data, B physics, precision electroweak data, vacuum stability, unitarity and perturbativity. The latter constraints restrict substantially the possibilities for enhancing the gg → h → γγ or gg → H → γγ signal relative to that for the SM Higgs, hSM. Further, we find that a large enhancement of the gg → h → γγ or gg → H → γγ signal in Type II models is possible only if the gg → h → ZZ or gg → H → ZZ mode is even more enhanced, a situation disfavored by current data. In contrast, in the Type I model one can achieve enhanced rates in the γγ final state for the h while having the ZZ mode at or below the SM rate — the largest [gg → h → γγ]/[gg → hSMγγ] ratio found is of order ~ 1.3 when the two Higgs doublet vacuum expectation ratio is tan β = 4 or 20 and the charged Higgs boson has its minimal LEP-allowed value of mH± = 90 GeV.
16931224
Loop induced W+- H-+ associated production via photon-photon collisions in the THDM and the MSSM
We study the loop induced production of charged Higgs boson associated with W-boson via photon-photon collisions at linear colliders (LC). The investigation is carried out under the two-Higgs-doublet model(THDM) and the minimal supersymmetric model (MSSM) using full on-mass-shell renormalization scheme. The numerical analysis of their production rates is presented with some typical parameter sets. The results show that the total cross sections in frame of the MSSM at linear colliders(LC) can reach 0.1 femto barn quantitatively. The contributions from supersymmetric sector can lead to an order of magnitude enhancement of the cross section in some parameter space. We conclude that the associated WH production rate in photon-photon collision mode is comparable to that in ee collision mode. PACS number(s): 12.60.Jv, 12.60.Fr, 12.15.Lk, 13.85.-t The project supported by National Natural Science Foundation of China