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1.
Searching for the top squark(stop)is a key task to test the naturalness of SUSY.Different from stop pair production,single stop production relies on its electroweak properties and can provide some unique signatures.Following the single production process pp→t~1X(~)1→tX~10X~1-,the top quark has two decay channels:leptonic channel and hadronic channel.In this paper,we probe the observability of these two channels in a simplified minimal supersymmetric standard model scenario.We find that,at the 27 TeV LHC with the integrated luminosity of L=15 ab-1,mt-1<1900 GeV andμ<750 GeV can be excluded at 2σthrough the leptonic mono-top channel,while mt-1<1200 GeV andμ<350 GeV can be excluded at 2σthrough the hadronic channel. 相似文献
2.
Systems described by an O(n) symmetrical varphi;{4} Hamiltonian are considered in a d-dimensional film geometry at their bulk critical points. The critical Casimir forces between the film's boundary planes B_{j}, j=1,2, are investigated as functions of film thickness L for generic symmetry-preserving boundary conditions partial differential_{n}phi=c[over composite function]_{j}phi. The L-dependent part of the reduced excess free energy per cross-sectional area takes the scaling form f_{res} approximately D(c_{1}L;{Phi/nu},c_{2}L;{Phi/nu})/L;{d-1} when d<4, where c_{i} are scaling fields associated with the variables c[over composite function]_{i} and Phi is a surface crossover exponent. Explicit two-loop renormalization group results for the function D(c_{1},c_{2}) at d=4- dimensions are presented. These show that (i) the Casimir force can have either sign, depending on c_{1} and c_{2}, and (ii) for appropriate choices of the enhancements c[over composite function]_{j}, crossovers from attraction to repulsion and vice versa occur as L increases. 相似文献
3.
Tonietto Serena Nestola Fabrizio Redhammer Gunther J. Silvestri Alberta Molin Gianmario Bruno Marco 《Applied Physics A: Materials Science & Processing》2011,103(1):207-212
The mineral inclusions of two orange glass tesserae from paleo-Christian mosaics were investigated in order to derive the
melting temperature reached during their production (sourced from Padua and Vicenza, Veneto region, Italy). In particular,
clinopyroxene crystals were studied by single-crystal X-ray diffraction and electron microprobe WDS analysis. The crystals
show C2/c symmetry, typical of disordered Ca/Na and Mg/Al distributions indicating high-temperature of formation (>700°C). The cation
site populations were obtained by combining results from the two experimental techniques enabled us to derive the following
stoichiometric formula:
lM2[Ca0.819Na0.172Mn0.006K0.003]M1[Mg0.765Fe3+0.210 Cu0.015Ti0.006Zn0.006]T[Si1.933Al0.037Sn0.024]O6\begin{array}{l}{}^{M2}[\mathrm{Ca}_{0.819}\mathrm{Na}_{0.172}\mathrm{Mn}_{0.006}\mathrm{K}_{0.003}]{}^{M1}[\mathrm{Mg}_{0.765}\mathrm{Fe}^{3+}_{0.210}\\[3pt]\quad{}\mathrm{Cu}_{0.015}\mathrm{Ti}_{0.006}\mathrm{Zn}_{0.006}]{}^{T}[\mathrm{Si}_{1.933}\mathrm{Al}_{0.037}\mathrm{Sn}_{0.024}]\mathrm{O}_{6}\end{array} 相似文献
4.
We continue our study of the collision of two solitons for the subcritical generalized KdV equations
5.
《The European Physical Journal C - Particles and Fields》2007,52(4):1021-1023
In an earlier paper [1], the background for Ke3 was over estimated due to an erroneous calculation of the electron identification efficiency. The correct ratios of the partial
widths involving this channel are and . Assuming the PDG value [2] for the K2π branching ratio, the measured branching fraction of Br (Ke3) continues to exceed the current PDG value [2]. The extracted value of |Vus|f+(0) is in agreement with the CKM unitary prediction; thus, our conclusions in [1] do not change.
The online version of the original article can be found at 相似文献
6.
Valter Moretti 《Communications in Mathematical Physics》2006,268(3):727-756
This work concerns some features of scalar QFT defined on the causal boundary
of an asymptotically flat at null infinity spacetime and based on the BMS-invariant Weyl algebra
.(a) (i) It is noticed that the natural BMS invariant pure quasifree state λ on
, recently introduced by Dappiaggi, Moretti and Pinamonti, enjoys positivity of the self-adjoint generator of u-translations with respect to every Bondi coordinate frame
on
, (
being the affine parameter of the complete null geodesics forming
and
complex coordinates on the transverse 2-sphere). This fact may be interpreted as a remnant of the spectral condition inherited from QFT in Minkowski spacetime (and it is the spectral condition for free fields when the bulk is the very Minkowski space). (ii) It is also proved that the cluster property under u-displacements is valid for every (not necessarily quasifree) pure state on
which is invariant under u displacements. (iii) It is established that there is exactly one algebraic pure quasifree state which is invariant under u-displacements (of a fixed Bondi frame) and has positive self-adjoint generator of u-displacements. It coincides with the GNS-invariant state λ. (iv) Finally it is shown that in the folium of a pure u-displacement invariant state ω (like λ but not necessarily quasifree) on
is the only state invariant under u-displacement.(b) It is proved that the theory can be formulated for spacetimes asymptotically flat at null infinity which also admit future time completion i
+ (and fulfill other requirements related with global hyperbolicity). In this case a -isomorphism ı exists - with a natural geometric meaning - which identifies the (Weyl) algebra of observables of a linear field propagating in the bulk spacetime with a sub algebra of
. Using ı a preferred state on the field algebra in the bulk spacetime is induced by the BMS-invariant state λ on
. 相似文献
7.
K. Ozga G. Lakshminarayana M. Szota M. Nabialek S. Tkaczyk V. Kapustianyk V. Rudyk G. Myronchuk S. Danylchuk A. O. Fedorchuk 《Optical and Quantum Electronics》2013,45(10):1115-1124
The occurrence of linear electrooptics and optical anisotropy is observed in the ferroic crystals $[\hbox {NH}_{2}(\hbox {C}_{2}\hbox {H}_{5})_{2}]_{2} \hbox {CuCl}_{4 }$ [ NH 2 ( C 2 H 5 ) 2 ] 2 CuCl 4 embedded into polymethylmethacrylate polymer matrix. The studies were performed for the optically treated bulk crystals and the large-size nanocrystals (with sizes higher than 50 nm) embedded into the polymer matrix. The specimens were both in a form of bulk as well as in the form of the composite films. To understand the mechanisms giving the principal role to the effect we have performed polarized absorption measurements for the samples treated in the external dc-electric field and bicolour 532 nm/1,064 nm laser treatments. The behaviour of the birefringence and of the linear electrooptics coefficients were studied within a temperature range covering the incommensurate phase existence. 相似文献
8.
Flows on (or variations of) discrete curves in
give rise to flows on a subalgebra of functions on that curve. For a special choice of flows and a certain subalgebra this is described by the Toda lattice hierarchy. Here it is shown that the canonical symplectic structure on
, which can be interpreted as the phase space of closed discrete curves in
with length N, induces Poisson commutation relations on the above-mentioned subalgebra which yield the tri-Hamiltonian poisson structure of the Toda lattice hierarchy. 相似文献
9.
H. Assaridis I. Panagiotopoulos A. Moukarika V. Papaefthymiou T. Bakas 《Hyperfine Interactions》2006,169(1-3):1331-1336
The magnetic critical behavior of the manganese perovskite series $ {\text{La}}_{{0.67 - y}} {\left( {{\text{Sr,}}\,\,{\text{Ba,}}\,\,{\text{Ca}}} \right)}_{{0.33 + y}} {\text{Mn}}_{{1 - x}} {\text{Sn}}_{x} {\text{O}}_{3}
10.
In an earlier paper [1], we reported the observation of photoconductivity from free-carrier absorption in [Hg, Cd]Te. By using samples of [Hg, Cd]Te with different electrical and alloy properties, we have improved the near-millimeter-wave (NMMW) responsivity by over two orders of magnitude. At 1.6 K a best sample responsivity of about 185 V/W and a bandwidth of over 5 MHz have been measured. This responsivity corresponds to a Johnson-noise-limited noise-equivalent-power (NEP) of 1.6 × 10–12
. Another sample of similar compposition yielded an NEP of 1.8 × 10–12
and a 25 MHz bandwidth. These results coupled with a wide spectral sensitivity [1] indicate that [Hg, Cd]Te NMMW detectors compare very favorably with similar InSb detectors [2]. 相似文献
11.
We introduce a new observable, "gluino m_{T2}," which is an application of the Cambridge m_{T2} variable to the process where gluinos are pair produced in a proton-proton collision and each gluino subsequently decays into two quarks and one lightest supersymmetric particle, i.e., g[over ]g[over ]-->qqchi[over ]_{1};{0}qqchi[over ]_{1};{0}. We show that the gluino m_{T2} can be utilized to measure the gluino mass and the lightest neutralino mass separately and also the 1st and 2nd generation squark masses if squarks are lighter than the gluino, thereby providing a good first look at the pattern of sparticle masses experimentally. 相似文献
12.
Satish D Joglekar 《Pramana》1989,32(3):195-207
We discuss the general theory of renormalization of unbroken gauge theories in the nonlinear gauges in which the gauge-fixing
term is of the form
We show that higher loop renormalization modifiesfα [A] to contain ghost terms of the form
and show how the corresponding ghost terms are deduced fromfα [A, c, c] uniquely. We show that the theory can be renormalized while preserving a modified form of BRS invariance by multiplicative
and independent renormalizations onA, c, g, η, ζ, τ. We briefly discuss the independence of the renormalized S-matrix from η,ζ, τ. 相似文献
13.
We consider the problem of identifying sharp criteria under which radial H 1 (finite energy) solutions to the focusing 3d cubic nonlinear Schrödinger equation (NLS) i? t u + Δu + |u|2 u = 0 scatter, i.e., approach the solution to a linear Schrödinger equation as t → ±∞. The criteria is expressed in terms of the scale-invariant quantities ${\|u_0\|_{L^2}\|\nabla u_0\|_{L^2}}
14.
The identification of the fougerite mineral responsible for the bluish-green shade of gleysols in aquifers as being the FeII???III oxyhydroxycarbonate $\text{GR}(\text{CO}_{3}^{2-})^*$ of formula, $[\text{Fe}^{\rm II}_{6x}\text{Fe}^{\rm III}_{6(1 - x)}\text{O}_{12}\text{H}_{2(7-3x)}]^{2+}\bullet[\text{CO}_{3}^{2-}\bullet3\text{H}_{2}\text{O}]^{2-}$ where the ferric molar ratio x = [FeIII/Fetotal] is restricted to the domain [1/3–2/3] induces to study the reactivity of the synthetic green rust for reducing some major pollutants. The oxidation within the solid compound $\text{GR}(\text{CO}_{3}^{2-})^*$ in the presence of nitrates is followed by miniaturized Mössbauer spectrometer (MIMOS). Ratio x = [FeIII/Fetotal] increases up to 0.67 where $\text{GR}(\text{CO}_{3}^{2-})^*$ transforms gradually into magnetite. This could well explain the composition variability of fougerite occurrences. 相似文献
15.
Markus Heydenreich Remco van der Hofstad 《Communications in Mathematical Physics》2007,270(2):335-358
We investigate the scaling of the largest critical percolation cluster on a large d-dimensional torus, for nearest-neighbor percolation in sufficiently high dimensions, or when d > 6 for sufficiently spread-out percolation. We use a relatively simple coupling argument to show that this largest critical
cluster is, with high probability, bounded above by a large constant times V
2/3 and below by a small constant times , where V is the volume of the torus. We also give a simple criterion in terms of the subcritical percolation two-point function on
under which the lower bound can be improved to small constant times , i.e. we prove random graph asymptotics for the largest critical cluster on the high-dimensional torus. This establishes a conjecture by [1], apart from logarithmic
corrections. We discuss implications of these results on the dependence on boundary conditions for high-dimensional percolation.
Our method is crucially based on the results in [11, 12], where the scaling was proved subject to the assumption that a suitably defined critical window contains the percolation threshold on . We also strongly rely on mean-field results for percolation on proved in [17–20]. 相似文献
16.
J. Ellis F. Moortgat G. Moortgat-Pick J. M. Smillie J. Tattersall 《The European Physical Journal C - Particles and Fields》2009,60(4):633-651
We study the potential observation at the LHC of CP-violating effects in stop production and subsequent cascade decays,
,
,
, within the Minimal Supersymmetric Standard Model. We study T-odd asymmetries based on triple products between the different
decay products. There may be a large CP asymmetry at the parton level, but there is a significant dilution at the hadronic
level after integrating over the parton distribution functions. Consequently, even for scenarios where large CP intrinsic
asymmetries are expected, the measurable asymmetry is rather small. High luminosity and precise measurements of masses, branching
ratios and CP asymmetries may enable measurements of the CP-violating parameters in cascade decays at the LHC. 相似文献
17.
P. Huber S. Grüner C. Schäfer K. Knorr A. V. Kityk 《The European physical journal. Special topics》2007,141(1):101-105
We present measurements on the capillary rise of water and
two linear alkanes (n-C16H34, n-C24H50) in
nanopores of monolithic Vycor glass (mean pore radius 5 nm).
Measurements of the mass uptake as a function of time, m(t), are
in good agreement with the Lucas–Washburn
–prediction
typical of imbibition of liquids into porous hosts. The relative
capillary rise velocities of the liquids investigated scale as
expected from the bulk fluid parameters. 相似文献
18.
We prove bounds on moments of the Smoluchowski coagulation equations with diffusion, in any dimension d ≥ 1. If the collision propensities α(n, m) of mass n and mass m particles grow more slowly than , and the diffusion rate is non-increasing and satisfies for some b
1 and b
2 satisfying 0 ≤ b
2 < b
1 < ∞, then any weak solution satisfies for every and T ∈(0, ∞), (provided that certain moments of the initial data are finite). As a consequence, we infer that these conditions
are sufficient to ensure uniqueness of a weak solution and its conservation of mass.
This work was performed while A.H. held a postdoctoral fellowship in the Department of Mathematics at U.B.C.
This work is supported in part by NSF grant DMS0307021. 相似文献
19.
L. C. Shepley 《Communications in Mathematical Physics》1968,9(4):313-326
The postulate is made that across a given hypersurfaceN the metric and its first derivatives are continuous. This postulate is used to derive conditions which must be satisfied by discontinuities in the Riemann tensor acrossN. These conditions imply that the conformal tensor jump is uniquely determined by the stress-energy tensor discontinuity ifN is non-null (and to within an additive term of type Null ifN is lightlike). Alternatively,
and [R] determine
ifN is non-null. These relationships between the conformal tensor and stress-energy tensor jumps are given explicitly in terms of a three-dimensional complex representation of the antisymmetric tensors. Application of these results to perfect-fluid discontinuities is made:
is of type D across a fluid-vacuum boundary and across an internal, non-null shock front.
is of type I (non-degenerate) in general across fluid interfaces across which no matter flows, except for special cases.The research reported herein was supported in part by the Atomic Energy Commission under contract number AT (11-1)-34, Project Agreement No. 125, while the author was at the University of California at Berkeley, and in part by National Science Foundation Grant GU-1598-University Science Development Program. 相似文献
20.
Foias, Guillopé, & Temam showed in 1985 that for a given weak solution of the three-dimensional Navier-Stokes equations on a domain Ω, one can define a ‘trajectory mapping’ that gives a consistent choice of trajectory through each initial condition , and that respects the volume-preserving property one would expect for smooth flows. The uniqueness of this mapping is guaranteed
by the theory of renormalised solutions of non-smooth ODEs due to DiPerna & Lions.
However, this is a distinct question from the uniqueness of individual particle trajectories. We show here that if one assumes
a little more regularity for u than is known to be the case, namely that , then the particle trajectories are unique and C
1 in time for almost every choice of initial condition in Ω. This degree of regularity is more than can currently be guaranteed
for weak solutions () but significantly less than that known to ensure that u is regular ( . We rely heavily on partial regularity results due to Caffarelli, Kohn, & Nirenberg and Ladyzhenskaya & Seregin. 相似文献
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