Superhyperfine Structures in ESR and ENDOR of Cubic CdTe:Mn2+

Superhyperfine structure tensors for the 12 next‐nearest ligands in CdTe:Mn2+ have been expressed in terms of molecular orbital and geometry parameters. ESR and ENDOR transition frequencies are related to the superhyperfine tensor components. An attempt is made to obtain the amount of d‐electron delocalization from such relations.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70842/2/JCPSA6-42-1-189-1.pd

Mechanism of Superhyperfine Structure in SnO2:V4+

Molecular orbital theory has been applied to SnO2:V4+ to account for the large and small superhyperfine structure observed by From et al. The unpaired spin density at the next‐nearest ligand tin nucleus is formulated. The result can be intepreted as due to two electron‐transfer processes. The first comes from the formation of antibonding molecular orbital. The second arises from the configuration mixing. The first process is found to be dominant and is proportional to the square of overlap integral between vanadium 3d and tin 5s orbitals. Calculated ratio of the large and small superhyperfine structure is in good agreement with experiment.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/71190/2/JCPSA6-42-1-186-1.pd

Probing anomalous ZγγγZ\gamma\gamma\gamma couplings at a future muon collider

The sensitivity to anomalous quartic gauge couplings (AQGCs) of the $\gamma\gamma\gamma Z$ interaction is studied in the $\mu^+\mu^- \rightarrow \mu^+\gamma\gamma \mu^-$ scattering at a future muon collider with unpolarized beams. The anomalous $\gamma\gamma\gamma Z$ vertex is described by two couplings, $\zeta_1$ and $\zeta_2$. The differential and total cross sections are calculated for the center-of-mass energies of 3 TeV, 14 TeV, and 100 TeV. For these values of the collision energy the $95\%$ C.L. exclusion regions for AQGCs are obtained depending on the systematic error. In particular, for the 14 TeV muon collider with the integrated luminosity $L = 20$ ab$^{-1}$ the best sensitivities are derived to be $\zeta_1 = 3.1 \times 10^{-5}$ TeV$^{-4}$ and $\zeta_2 = 6.5 \times 10^{-5}$ TeV$^{-4}$. These constraints are three orders of magnitude stronger than the bounds obtained for the 27 TeV HE-LHC with $L = 15$ ab$^{-1}$. At the 100 TeV muon collider with $L = 1000$ ab$^{-1}$ AQGCs can be probed up to $(1.64 \div 3.4) \times 10^{-8}$ TeV$^{-4}$. The partial-wave unitarity constraints on couplings $\zeta_1$, $\zeta_2$ are evaluated. It is shown that the unitarity is not violated in the region of the AQGCs examined in the present paper.Comment: 23 pages, 6 figure

Probing anomalous γγγγ\gamma\gamma\gamma\gamma couplings at a future muon collider

We have studied anomalous four-photon couplings in the $\mu^+\mu^- \rightarrow \mu^+ \gamma\gamma \mu^-$ scattering at a future muon collider, assuming that anomalous quartic gauge couplings with one or two $Z$ bosons are zero. The collision energies of 3 TeV, 14 TeV, and 100 TeV are addressed. Both differential and total cross sections versus invariant mass of the outgoing photons are calculated. The best 95\% C.L. exclusion bounds on anomalous couplings are obtained to be $g_1 = 2.23 \times 10^{-8}$ TeV$^{-4}$ and $g_2 = 4.22 \times 10^{-8}$ TeV$^{-4}$. They correspond to the muon collision energy of 100 TeV. The partial-wave unitary constraints on $g_1$ and $g_2$ are examined. We have demonstrated that the unitarity is not violated in a region of the anomalous couplings obtained in the present paper.Comment: 24 pages, 6 figure

Robust estimation in flat fading channels under bounded channel uncertainties

Cataloged from PDF version of article.We investigate channel equalization problem for time-varying flat fading channels under bounded channel uncertainties. We analyze three robust methods to estimate an unknown signal transmitted through a time-varying flat fading channel. These methods are based on minimizing certain meansquare error criteria that incorporate the channel uncertainties into their problem formulations instead of directly using the inaccurate channel information that is available. We present closed-form solutions to the channel equalization problems for each method and for both zero mean and nonzero mean signals. We illustrate the performances of the equalization methods through simulations. © 2013 Elsevier Inc. All rights reserved

Cross-Sender Bit-Mixing Coding

Scheduling to avoid packet collisions is a long-standing challenge in networking, and has become even trickier in wireless networks with multiple senders and multiple receivers. In fact, researchers have proved that even {\em perfect} scheduling can only achieve $\mathbf{R} = O(\frac{1}{\ln N})$. Here $N$ is the number of nodes in the network, and $\mathbf{R}$ is the {\em medium utilization rate}. Ideally, one would hope to achieve $\mathbf{R} = \Theta(1)$, while avoiding all the complexities in scheduling. To this end, this paper proposes {\em cross-sender bit-mixing coding} ({\em BMC}), which does not rely on scheduling. Instead, users transmit simultaneously on suitably-chosen slots, and the amount of overlap in different user's slots is controlled via coding. We prove that in all possible network topologies, using BMC enables us to achieve $\mathbf{R}=\Theta(1)$. We also prove that the space and time complexities of BMC encoding/decoding are all low-order polynomials.Comment: Published in the International Conference on Information Processing in Sensor Networks (IPSN), 201

Large Extra Dimension effects through Light-by-Light Scattering at the CERN LHC

Observing light-by-light scattering at the Large Hadron Collider (LHC) has received quite some attention and it is believed to be a clean and sensitive channel to possible new physics. In this paper, we study the diphoton production at the LHC via the process $\rm pp\rightarrow p\gamma\gamma p\rightarrow p\gamma\gamma p$ through graviton exchange in the Large Extra Dimension (LED) model. Typically, when we do the background analysis, we also study the Double Pomeron Exchange (DPE) of $\gamma\gamma$ production. We compare its production in the quark-quark collision mode to the gluon-gluon collision mode and find that contributions from the gluon-gluon collision mode are comparable to the quark-quark one. Our result shows, for extra dimension $\delta=4$, with an integrated luminosity $\rm {\cal L} = 200 fb^{-1}$ at the 14 TeV LHC, that diphoton production through graviton exchange can probe the LED effects up to the scale $\rm M_S=5.06 (4.51, 5.11) TeV$ for the forward detector acceptance $\xi_1 (\xi_2, \xi_3)$, respectively, where $0.0015<\xi_1<0.5$, $0.1<\xi_2<0.5$ and $0.0015<\xi_3<0.15$.Comment: 25 pages. 7 figs. Change some grammatical error

Benefits of Project Management to Realizing Sustainable Buildings

Sustainable materials are becoming popular worldwide in terms of ecologically friendly structures that deal with pollution controls, climate change, global temperature increase, and resource conservation issues. Consequently, the researchers believe that simply using sustainable materials to design and create a building is insufficient. This article discusses several elements of sustainable construction planning including site choice mostly through the proposed project, material classification mostly through the life cycle, analysis time, cost, and commodity controls, reliability and stability, occupant health, manufacturing methodologies and procedures, and design concepts based on advanced ideas. The article argues that by integrating the choice of building components and construction strategic planning practices into the project, the productivity and consequently the reliability of the building could be significantly improved. The article also discusses the advantages and requirements of sustainable construction, the managerial roles in construction procedure, management processes, and a correlation of conventional construction planning and sustainable project management. The research paper indicates that the objective of constructing an environmentally friendly building is simply fully done when the notion of sustainability is integrated into every phase of the construction approach and that the procedures are not restricted to using recycled practices

Spin Resonance of SnO2:V and the Vanadium 3d Electron Orbital

The ESR spectrum of SnO2 containing about 0.5% vanadium observed in K band at liquid‐nitrogen temperature shows two sets of shfs. Relative intensity measurements show that the large shfs (168 G) is due to the two tins located along the c axis and the small shfs (28 G) due to the four tins lying in a diagonal plane of the unit cell containing four oxygens. The large shfs is largely isotropic, with an axial maximum along the c axis. This suggests that the ground electron level is 3d(x2−y2). The next level is 3d(xz). This is deduced from the g values (gxx = 1.939,gyy = 1.903,and gzz = 1.943)(gxx=1.939,gyy=1.903,andgzz=1.943).Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/71160/2/JCPSA6-42-1-181-1.pd