1,589 research outputs found
Sleptons without Hadrons
Multilepton searches for electroweakino and slepton pair production at hadron
colliders remain some of the best means to test weak-scale supersymmetry.
Searches at the CERN Large Hadron Collider, however, are limited by large
diboson and top quark pair backgrounds, despite the application of traditional,
central jet vetoes. In this context, we report the impact of introducing
dynamic jet vetoes in searches for colorless superpartners. As a representative
scenario, we consider the Drell-Yan production of a pair of right-handed smuons
decaying into a dimuon system accompanied with missing transverse energy. As an
exploratory step, we consider several global and local measures of the leptonic
and hadronic activity to construct the veto. In most all cases, we find that
employing a dynamic jet veto improves the sensitivity, independently of the
integrated luminosity. The inclusion of non-perturbative multiple particle
interactions and next-to-leading order jet merging does not alter this picture.
Directions for further improvements are discussed.Comment: 18 pages; 7 figures; additional discussions added; journal version;
results unchange
Odd Chern-Simons Theory, Lie Algebra Cohomology and Characteristic Classes
We investigate the generic 3D topological field theory within AKSZ-BV
framework. We use the Batalin-Vilkovisky (BV) formalism to construct explicitly
cocycles of the Lie algebra of formal Hamiltonian vector fields and we argue
that the perturbative partition function gives rise to secondary characteristic
classes. We investigate a toy model which is an odd analogue of Chern-Simons
theory, and we give some explicit computation of two point functions and show
that its perturbation theory is identical to the Chern-Simons theory. We give
concrete example of the homomorphism taking Lie algebra cocycles to
Q-characteristic classes, and we reinterpreted the Rozansky-Witten model in
this light.Comment: 52 page
Students’ Interest in Physical Education and Sports.
У статті зазначено, що в процесі навчання у вищому навчальному закладі простежено тенденцію до зниження рівня інтересу студентів до фізичного виховання й спорту. The tendency of decline of students’ interest in physical education and sports during studying at higher education institution is indicated in the article
The antifield Koszul-Tate complex of reducible Noether identities
A generic degenerate Lagrangian system of even and odd fields is examined in
algebraic terms of the Grassmann-graded variational bicomplex. Its
Euler-Lagrange operator obeys Noether identities which need not be independent,
but satisfy first-stage Noether identities, and so on. We show that, if a
certain necessary and sufficient condition holds, one can associate to a
degenerate Lagrangian system the exact Koszul-Tate complex with the boundary
operator whose nilpotency condition restarts all its Noether and higher-stage
Noether identities. This complex provides a sufficient analysis of the
degeneracy of a Lagrangian system for the purpose of its BV quantization.Comment: 23 page
Cohomology of Lie superalgebras and of their generalizations
The cohomology groups of Lie superalgebras and, more generally, of color Lie
algebras, are introduced and investigated. The main emphasis is on the case
where the module of coefficients is non-trivial. Two general propositions are
proved, which help to calculate the cohomology groups. Several examples are
included to show the peculiarities of the super case. For L = sl(1|2), the
cohomology groups H^1(L,V) and H^2(L,V), with V a finite-dimensional simple
graded L-module, are determined, and the result is used to show that
H^2(L,U(L)) (with U(L) the enveloping algebra of L) is trivial. This implies
that the superalgebra U(L) does not admit of any non-trivial formal
deformations (in the sense of Gerstenhaber). Garland's theory of universal
central extensions of Lie algebras is generalized to the case of color Lie
algebras.Comment: 50 pages, Latex, no figures. In the revised version the proof of
Lemma 5.1 is greatly simplified, some references are added, and a pertinent
result on sl(m|1) is announced. To appear in the Journal of Mathematical
Physic
Cyclic Statistics In Three Dimensions
While 2-dimensional quantum systems are known to exhibit non-permutation,
braid group statistics, it is widely expected that quantum statistics in
3-dimensions is solely determined by representations of the permutation group.
This expectation is false for certain 3-dimensional systems, as was shown by
the authors of ref. [1,2,3]. In this work we demonstrate the existence of
``cyclic'', or , {\it non-permutation group} statistics for a system of n
> 2 identical, unknotted rings embedded in . We make crucial use of a
theorem due to Goldsmith in conjunction with the so called Fuchs-Rabinovitch
relations for the automorphisms of the free product group on n elements.Comment: 13 pages, 1 figure, LaTex, minor page reformattin
Hysteresis phenomenon in deterministic traffic flows
We study phase transitions of a system of particles on the one-dimensional
integer lattice moving with constant acceleration, with a collision law
respecting slower particles. This simple deterministic ``particle-hopping''
traffic flow model being a straightforward generalization to the well known
Nagel-Schreckenberg model covers also a more recent slow-to-start model as a
special case. The model has two distinct ergodic (unmixed) phases with two
critical values. When traffic density is below the lowest critical value, the
steady state of the model corresponds to the ``free-flowing'' (or ``gaseous'')
phase. When the density exceeds the second critical value the model produces
large, persistent, well-defined traffic jams, which correspond to the
``jammed'' (or ``liquid'') phase. Between the two critical values each of these
phases may take place, which can be interpreted as an ``overcooled gas'' phase
when a small perturbation can change drastically gas into liquid. Mathematical
analysis is accomplished in part by the exact derivation of the life-time of
individual traffic jams for a given configuration of particles.Comment: 22 pages, 6 figures, corrected and improved version, to appear in the
Journal of Statistical Physic
Operation modes of a hydro-generator as a part of the inverter micro hydropower plant
The paper dwells on the selection problem of power equipment for a stand-alone inverter micro hydropower plant, in particular a hydro-generator, and evaluation of its operation modes. Numerical experiments included the modes calculation of hydroelectric units of the same type with various nominal power, supplied to the consumer according to the unchanged electric load curve. The studies developed requirements for a hydro-turbine and a synchronous generator in terms of a speed range and installed capacity, depending on the load curve. The possibility of using general industrial hydroelectric units with nominal power equal to half-maximum capacity of a typical daily load curve in rural areas was shown
Ground of the System of the physical Loadings, directed on Making healthy and Increase of Capacity in the conditions of Dwelling on muddy by a radiation Territory.
У статті обґрунтувано рекомендації щодо використання засобів фізичного виховання для корекції фізичного розвитку, підвищення функціональних можливостей і фізичної працездатності населення, яке проживає на
забруднених радіонуклідами територіях. In the article grounded recommendation in relation to the use of facilities of physical
education for the correction of physical development, increase of functional possibilities and physical capacity of
population which lives on muddy by a radiation territory
Cross-over behaviour in a communication network
We address the problem of message transfer in a communication network. The
network consists of nodes and links, with the nodes lying on a two dimensional
lattice. Each node has connections with its nearest neighbours, whereas some
special nodes, which are designated as hubs, have connections to all the sites
within a certain area of influence. The degree distribution for this network is
bimodal in nature and has finite variance. The distribution of travel times
between two sites situated at a fixed distance on this lattice shows fat
fractal behaviour as a function of hub-density. If extra assortative
connections are now introduced between the hubs so that each hub is connected
to two or three other hubs, the distribution crosses over to power-law
behaviour. Cross-over behaviour is also seen if end-to-end short cuts are
introduced between hubs whose areas of influence overlap, but this is much
milder in nature. In yet another information transmission process, namely, the
spread of infection on the network with assortative connections, we again
observed cross-over behaviour of another type, viz. from one power-law to
another for the threshold values of disease transmission probability. Our
results are relevant for the understanding of the role of network topology in
information spread processes.Comment: 12 figure
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