Reconstruction of $$ \tilde \tau _1 $$ mass at the LHC

The cascade mass reconstruction approach was used for mass reconstruction of the lightest $ \tilde \tau $ \tilde \tau produced at the LHC in the cascade decay $ \tilde g \to \tilde bb \to \tilde \chi _2^0 bb \to \tilde \tau _1 \tau bb \to \tilde \chi _1^0 \tau \tau bb $ \tilde g \to \tilde bb \to \tilde \chi _2^0 bb \to \tilde \tau _1 \tau bb \to \tilde \chi _1^0 \tau \tau bb . The $ \tilde \tau _1 $ \tilde \tau _1 mass was reconstructed assuming that masses of gluino, bottom squark, and two lightest neutralinos were reconstructed in advance. SUSY data sample sets for the SU(3) model point containing 160k events each were generated which corresponded to an integrated luminosity of about 8 fb⁻¹ at 14 TeV. These events were passed through the AcerDET detector simulator, which parametrized the response of a generic LHC detector. The mass of the $ \tilde \tau _1 $ \tilde \tau _1 was reconstructed with a precision of about 20% on average.     

Maps on positive definite operators preserving the quantum $$\chi _\alpha ^2$$-divergence

We describe the structure of all bijective maps on the cone of positive definite operators acting on a finite and at least two-dimensional complex Hilbert space which preserve the quantum \(\chi _\alpha ^2\)-divergence for some \(\alpha \in [0,1]\). We prove that any such transformation is necessarily implemented by either a unitary or an antiunitary operator. Similar results concerning maps on the cone of positive semidefinite operators as well as on the set of all density operators are also derived.     

Study of Inelastic $$\boldsymbol{A}$$ ( $$\boldsymbol{p,p^{\prime}}$$ ) $$\boldsymbol{X}$$ Reaction with $${}^{\mathbf{9}}$$ Be and $${}^{\mathbf{90}}$$ Zr Nuclei at 1 GeV

Physics of Atomic Nuclei - The secondary proton polarization and differential cross sections of the ( $$p,p^{\prime}$$ ) inelastic reaction on nuclei $${}^{9}$$ Be and $${}^{90}$$ Zr at the initial...     

Proton-antiproton annihilation into a \Lambda_{c}^{+} \bar{{\Lambda}}_{c}^{-} pair

The process p $ \bar{{p}}$ $ \rightarrow$ $ \Lambda_{c}^{+}$ $ \bar{{\Lambda}}_{c}^{-}$ is investigated within the handbag approach. It is shown to lowest order of perturbative QCD that, under the assumption of restricted parton virtualities and transverse momenta, the dominant dynamical mechanism, characterized by the partonic subprocess u $ \bar{{u}}$ $ \rightarrow$ c $ \bar{{c}}$ , factorizes in the sense that only the subprocess contains highly virtual partons, namely a gluon, while the hadronic matrix elements embody only soft scales and can be parameterized in terms of helicity flip and non-flip generalized parton distributions. Modelling the latter functions by overlaps of light-cone wave functions for the involved baryons we are able to predict cross-sections and spin correlation parameters for the process of interest.     

$$\mathbb{C}^2/\mathbb{Z}_{n}$$ Fractional Branes and Monodromy

We construct geometric representatives for the fractional branes in terms of branes wrapping certain exceptional cycles of the resolution. In the process we use large radius and conifold-type monodromies, and also check some of the orbifold quantum symmetries. We find the explicit Seiberg-duality which connects our fractional branes to the ones given by the McKay correspondence. We also comment on the Harvey-Moore BPS algebras.     

$$\mathrm{SL}(2, \mathbb {C})$$ group action on cohomological field theories

We introduce the \(\mathrm {SL} (2,\mathbb {C})\) group action on a partition function of a cohomological field theory via a certain Givental’s action. Restricted to the small phase space we describe the action via the explicit formulae on a CohFT genus g potential. We prove that applied to the total ancestor potential of a simple-elliptic singularity the action introduced coincides with the transformation of Milanov–Ruan changing the primitive form (cf. Milanov and Ruan in Gromov–Witten theory of elliptic orbifold \(\mathbb {P}^{1}\) and quasi-modular forms, arXiv:1106.2321, 2011).     

Self-Consistent Calculations of Probabilities for Transitions between $${3}_{1}^{{-}}$$ and $${2}_{1}^{{+}}$$ One-Phonon States in Tin Isotopes

Physics of Atomic Nuclei - For the first time, a self-consistent method for studying second-order anharmonic effects within quantum many-body theory is applied to calculating probabilities for...     

The small x gluon and $b\bar{b}$ production at the LHC

We study open b[`(b)]b\bar{b} production at large rapidity at the LHC in an attempt to pin down the gluon distribution at very low x. For the LHC energy of 7 TeV, at next-to-leading order (NLO), there is a large factorization scale uncertainty. We show that the uncertainty can be greatly reduced if events are selected in which the transverse momenta of the two B-mesons balance each other to some accuracy, that is |p _1T +p _2T |<k ₀. This will fix the scale μ _F ≃k ₀, and will allow the LHCb experiment, in particular, to study the x-behaviour of gluon distribution down to x∼10⁻⁵, at rather low scales, μ∼2 GeV. We evaluate the expected cross sections using, for illustrative purposes, various recent sets of Parton Distribution Functions.     

Analysis of Angular $$\boldsymbol{t{-}\gamma}$$ Correlations in the Reaction $${}^{\boldsymbol{27}}$$ Al $$\boldsymbol{(\alpha,t)^{28}}$$ Si(2 $${}^{\boldsymbol{+}}$$ )

Physics of Atomic Nuclei - Angular $$t$$ – $$\gamma$$ correlations measured earlier in the reaction $${}^{27}$$ Al $$(\alpha,t)^{28}$$ Si(2 $${}^{+}$$ ) occurring at $$E_{\alpha}=30.3$$ MeV...     

Sextonions,Zorn matrices,and $$\mathbf {e}_{\mathbf{7} \frac{\mathbf{1}}{\mathbf{2}}}$$

By exploiting suitably constrained Zorn matrices, we present a new construction of the algebra of sextonions (over the algebraically closed field \(\mathbb {C}\)). This allows for an explicit construction, in terms of Jordan pairs, of the non-semisimple Lie algebra \(\mathbf {e}_{\mathbf{7} \frac{\mathbf{1}}{\mathbf{2}}}\), intermediate between \(\mathbf {e_7}\) and \(\mathbf {e_8}\), as well as of all Lie algebras occurring in the sextonionic row and column of the extended Freudenthal Magic Square.     

Simultaneous Investigation of the Nuclear Reactions $${}^{11}$$ B $$\boldsymbol{(p,3\alpha)}$$ and $${}^{11}$$ B $$\boldsymbol{(p,n)^{11}}$$ C as a New Tool for Determining the Absolute Yield of Alpha Particles in Picosecond Plasmas

Physics of Atomic Nuclei - The results of experimental investigations devoted to initiating the promising nuclear fusion reaction $${}^{11}$$ B $$(p,3\alpha)$$ in picosecond laser plasmas at a...     

The strong vertices of charmed mesons D, $$D^{*}$$ and charmonia $$J/\psi $$ , $$\eta _{c}$$

The European Physical Journal A - In the international atomic energy agency report on compact accelerator based neutron sources, IAEA-TECDOC-1981, Table 1 lists the typical source strength...     

Effect of tensile and compressive strain on the magnetic ordering of the ($$\hbox {LaMnO}_{3})_{1}/\hbox {(SrTiO}_{3})_{1}$$ superlattice

We study the effects of tensile and compressive strain on the \((\hbox {LaMnO}_{3})_{1}/(\hbox {SrTiO}_{3})_{1}\) superlattice from density functional theory using Quantum-Espresso open source code. In the unstrained superlattice, electron interactions in out-of-plane Mn–O–Ti chains are dominated by superexchange interactions, giving rise to ferromagnetic and half-metallic conducting characters. We found that the most stable magnetic configuration is G-type antiferromagnetic configuration for strong compressive strain and for strong tensile strain it is A-type antiferromagnetic configuration. The results are in accordance with the experimental observations which show that the superlattices can be grown on different substrates, and due to the difference in lattice parameters of the substrate and the main layer, there are also changes in the amount of strain applied to the superlattice.     

Properties of $$\boldsymbol{B}_{\boldsymbol{c}}$$ Mesons and Variational Constraints on Their Masses

Physics of Atomic Nuclei - Spectrum, radii, radial wave functions at origin, decay constants, and momentum widths for radial and orbital excited $$B_{c}$$ mesons are derived within non-relativistic...