118415383
Instanton Effective Action in Deformed Super Yang-Mills Theories
We study the ADHM construction of instantons in N = 2 supersymmetric Yang‐Mills theory deformed in constant Ramond‐Ramond (R‐R) 3‐form field strength background in type IIB superstrings. We compare the deformed instanton effective action with the effective action of fractional D3/D(−1) branes at the orbifold singularity of C2/Z2 in the same R‐R background. We find discrepancy between them at the second order in deformation parameters, which comes from the coupling of the translational zero modes of the D(−1)‐branes to the R‐R background. We improve the deformed action by adding a term with spacetime dependent gauge coupling such that the action reproduces the effective action of the fractional branes.
2668770
Coupling between M2-branes and form fields
In the context of low-energy effective theory of multiple M2-branes, we construct the interaction terms between the world-volume fields of M2-branes and the antisymmetric tensor fields of three- and six-forms. By utilizing the compactification procedure, we show coincidence between the dimensionally reduced coupling and the R-R coupling to D-branes in type II string theory. We also discuss that a cubic term proportional to six-form field reproduces the quartic mass-deformation term in the world-volume theory of multiple M2-branes.
18268747
Central charges in non(anti)commutative N=2 supersymmetric U(N) gauge theory
Abstract We study the central charge of the deformed N = ( 1 , 0 ) supersymmetry algebra in non(anti)commutative N = 2 supersymmetric U ( N ) gauge theory. In the cases of N = 1 / 2 superspace and N = 2 harmonic superspace with the singlet deformation, we find that the central charge is deformed by the non(anti)commutative parameters but depends on the electric and magnetic charges. For generic deformation of N = 2 harmonic superspace, we compute the O ( C ) correction to the central charges in the case of U ( 1 ) gauge group.
56166210
Fermionic T-duality and Morita equivalence
In this paper we investigate the relationship between the so-called fermionic T-duality and the Morita equivalence of noncommutative supertori. We first get an action satisfying the BRST invariance under nonvanishing constant R-R and NS-NS backgrounds in the hybrid formalism. We investigate the effect of bosonic T-duality transformation together with fermionic T-duality transformation in this background and look for the resultant symmetry of transformations. We find that the duality transformations correspond to Morita equivalence of noncommutative supertori. In particular, we obtain the symmetry group $ {\text{SO}}\left( {2,2,\mathcal{V}_\mathbb{Z}^0} \right) $ in two dimensions, where $ \mathcal{V}_\mathbb{Z}^0 $ denotes Grassmann even number whose body part belongs to $ \mathbb{Z} $.
14784732
Instanton calculus in R-R 3-form background and deformed = 2 super Yang-Mills theory
We study the ADHM construction of instantons in = 2 supersymmetric Yang-Mills theory deformed in constant Ramond-Ramond (R-R) 3-form field strength background in type IIB superstrings. We compare the deformed instanton effective action with the effective action of fractional D3/D(−1) branes at the orbifold singularity of C2/Z2 in the same R-R background. We find discrepancy between them at the second order in deformation parameters, which comes from the coupling of the translational zero modes of the D(−1)-branes to the R-R background. We improve the deformed action by adding a term with space-time dependent gauge coupling. Although the space-time action differs from the action in the Ω-background, both actions lead to the same instanton equations of motion at the lowest order in gauge coupling.
17493300
Supersymmetric CPN Sigma Model on Noncommutative Superspace
We construct a closed form of the action of the supersymmetric CP N sigma model on noncommutative superspace in four dimensions. We show that this model has N = 1/2 supersymmetry and that the transformation law is not modified. The supersymmetric CP N sigma model on noncommutative superspace in two dimensions is obtained by dimensional reducing the model in four dimensions.
16605019
Testing the seesaw mechanism at collider energies in the Randall-Sundrum model
The Randall-Sundrum model with gauge fields and fermions in the bulk has several attractive features including the gauge coupling unification, a candidate for the dark matter, and an explanation for the hierarchical Yukawa couplings. 
In this paper, we point out that the 1st Kaluza-Klein modes of right-handed neutrinos may be produced at colliders, for both Dirac and Majorana neutrino cases. Furthermore, we can see whether the neutrino masses are Dirac type or Majorana type from the mass spectrum of KK particles.
119514655
What the Gribov copy tells about confinement and the theory of dynamical chiral symmetry breaking
We performed lattice Landau gauge QCD simulation on {beta}=6.0,16{sup 4},24{sup 4},32{sup 4} and {beta}=6.4,32{sup 4},48{sup 4} and 56{sup 4} by adopting the gauge fixing that minimizes the norm of the gauge field, and measured the running coupling by using the gluon propagator and the ghost propagator. In view of ambiguity in the vertex renormalization factor Z{sub 1} in the lattice, we adjust the normalization of the running coupling by the perturbative QCD results near the highest momentum point. It has a maximum {alpha}{sub s}(q){approx_equal}2.1(3) at around q=0.5 GeV and decreases as q approaches 0, and the Kugo-Ojima parameter reached -0.83(2). The infrared exponent of the ghost propagator at 0.4 GeV region is {alpha}{sub G}=0.20 but there is an exceptional Gribov copy with {alpha}{sub G}=0.27. The features of the exceptional Gribov copy are investigated by measuring four one-dimensional Fourier transform (1-d FT) of the gluon propagator transverse to each lattice axis. We observe, in general, correlation between absolute value of the Kugo-Ojima parameter and the degree of reflection positivity violation in the 1-d FT of the gluon propagator. The 1-d FT of the exceptional Gribov copy has an axis whose samplewise gluon propagator manifestly violates reflection positivity, and the average ofmore » the Cartan subalgebra components of the Kugo-Ojima parameter along this axis is consistent to -1. The running coupling of the ensemble average shows a suppression at 0 momentum, but when the ghost propagator of the exceptional Gribov copy is adopted, the suppression disappears and the data implies presence of the infrared fixed point {alpha}{sub s}(0){approx}2.5(5) and {kappa}=0.5 suggested by the Dyson-Schwinger approach in the multiplicative renormalizable scheme. Comparison with the SU(2) QCD and N{sub f}=2 unquenched SU(3) QCD are also made.« less
16902285
Energy-Scale Calibration of the Suzaku X-Ray Imaging Spectrometer Using the Checker Flag Charge-Injection Technique in Orbit
The X-ray Imaging Spectrometer (XIS) aboard the Suzaku satellite is an X-ray CCD camera system that has superior performance, such as a low background, high quantum efficiency, and good energy resolution in the 0.2–12 keV band. Because of radiation damage in orbit, however, the charge-transfer inefficiency (CTI) has increased, and hence the energy scale and resolution of the XIS has been degraded since the launch in 2005 July. The CCD has a charge-injection structure, and the CTI of each column and the pulse-height dependence of the CTI are precisely measured by a checker flag charge-injection (CFCI) technique. Our precise CTI correction improved the energy resolution from 230 eV to 190 eV at 5.9 keV in 2006 December. This paper reports on CTI measurements with the CFCI experiments in orbit. Using the CFCI results, we have implemented the time-dependent energy scale and resolution to the Suzaku calibration database.
10853977
Lectures on instanton counting
These notes have two parts. The first is a study of Nekrasov's deformed partition functions $Z(\ve_1,\ve_2,\vec{a};\q,\vec{\tau})$ of N=2 SUSY Yang-Mills theories, which are generating functions of the integration in the equivariant cohomology over the moduli spaces of instantons on $\mathbb R^4$. The second is review of geometry of the Seiberg-Witten curves and the geometric engineering of the gauge theory, which are physical backgrounds of Nekrasov's partition functions. 
The first part is continuation of math.AG/0306198, where we identified the Seiberg-Witten prepotential with $Z(0,0,\vec{a};\q,0)$. 
We put higher Casimir operators to the partition function and clarify their relation to the Seiberg-Witten $u$-plane. We also determine the coefficients of $\ve_1\ve_2$ and $(\ve_1^2+\ve_2^2)/3$ (the genus 1 part) of the partition function, which coincide with two measure factors $A$, $B$ appeared in the $u$-plane integral. 
The proof is based on the blowup equation which we derived in the previous paper.
14815866
Handsaw quiver varieties and finite W-algebras
Following Braverman-Finkelberg-Feigin-Rybnikov (arXiv:1008.3655), we study the convolution algebra of a handsaw quiver variety, a.k.a. a parabolic Laumon space, and a finite W-algebra of type A. This is a finite analog of the AGT conjecture on 4-dimensional supersymmetric Yang-Mills theory with surface operators. Our new observation is that the C^*-fixed point set of a handsaw quiver variety is isomorphic to a graded quiver variety of type A, which was introduced by the author in connection with the representation theory of a quantum affine algebra. As an application, simple modules of the W-algebra are described in terms of IC sheaves of graded quiver varieties of type A, which were known to be related to Kazhdan-Lusztig polynomials. This gives a new proof of a conjecture by Brundan-Kleshchev on composition multiplicities on Verma modules, which was proved by Losev, in a wider context, by a different method.