2,363 research outputs found
Visualizing Success: Investigating the Relationship between Ability and Self-Efficacy in the Domain of Visual Processing
The purpose of this study is to investigate the spatial reasoning capacities and related self-efficacy beliefs of student teachers. In recent years self-efficacy has been a focal point for those investigating various modes of determinism. The relationship between an individual’s perceptions of their ability to succeed within spatial reasoning tasks is examined in conjunction with their spatial reasoning ability. In this study three tests of spatial ability were administered to align with three unique spatial factors associated with mental rotation. These include Spatial Relations, Speeded Rotation and Spatial Orientation. Self-efficacy within the spatial domain is measured using an adapted Academic Self-Efficacy scale
Framing Spatial Cognition: Establishing a Research Agenda
A significant aim of research concerning human intelligence is to develop a comprehensive cognitive map of the human intelligence structure. The evolution of this knowledge base is mirrored through the chronological development of models which frame cognitive domains. The domain of Visual Processing (Gv), commonly known as spatial ability, is a domain which has seen significant advances in the pertinent knowledge base. Models framing this cognitive structure are arguably under-evolved through a lack of representation of factors identified in contemporary research. This paper presents the initial conception of a more comprehensive theoretical framework which builds upon existing theory. It is envisioned that such a framework could support further research exploring the nature of thinking in graphics and other related disciplines. A research agenda is discussed concerning the validation of this framework and its utilization in the holistic assessment of spatial ability
Spin Discrimination in Three-Body Decays
The identification of the correct model for physics beyond the Standard Model
requires the determination of the spin of new particles. We investigate to
which extent the spin of a new particle can be identified in scenarios
where it decays dominantly in three-body decays . Here we
assume that is a candidate for dark matter and escapes direct detection at
a high energy collider such as the LHC. We show that in the case that all
intermediate particles are heavy, one can get information on the spins of
and at the LHC by exploiting the invariant mass distribution of the two
standard model fermions. We develop a model-independent strategy to determine
the spins without prior knowledge of the unknown couplings and test it in a
series of Monte Carlo studies.Comment: 31+1 pages, 4 figures, 8 tables, JHEP.cls include
Diagnosing Spin at the LHC via Vector Boson Fusion
We propose a new technique for determining the spin of new massive particles
that might be discovered at the Large Hadron Collider. The method relies on
pair-production of the new particles in a kinematic regime where the vector
boson fusion production mechanism is enhanced. For this regime, we show that
the distribution of the leading jets as a function of their relative azimuthal
angle can be used to distinguish spin-0 from spin-1/2 particles. We illustrate
this effect by considering the particular cases of (i) strongly-interacting,
stable particles and (ii) supersymmetric particles carrying color charge. We
argue that this method should be applicable in a wide range of new physics
scenarios.Comment: 5 pages, 4 figure
The Maximal Inverse Seesaw from Operator and Oscillating Asymmetric Sneutrino Dark Matter
The maximal supersymmetric inverse seesaw mechanism (MSIS)
provides a natural way to relate asymmetric dark matter (ADM) with neutrino
physics. In this paper we point out that, MSIS is a natural outcome if one
dynamically realizes the inverse seesaw mechanism in the next-to minimal
supersymmetric standard model (NMSSM) via the dimension-five operator
, with the NMSSM singlet developing TeV scale VEV; it
slightly violates lepton number due to the suppression by the fundamental scale
, thus preserving maximally. The resulting sneutrino is a
distinguishable ADM candidate, oscillating and favored to have weak scale mass.
A fairly large annihilating cross section of such a heavy ADM is available due
to the presence of singlet.Comment: journal versio
General analysis of signals with two leptons and missing energy at the Large Hadron Collider
A signal of two leptons and missing energy is challenging to analyze at the
Large Hadron Collider (LHC) since it offers only few kinematical handles. This
signature generally arises from pair production of heavy charged particles
which each decay into a lepton and a weakly interacting stable particle. Here
this class of processes is analyzed with minimal model assumptions by
considering all possible combinations of spin 0, 1/2 or 1, and of weak
iso-singlets, -doublets or -triplets for the new particles. Adding to existing
work on mass and spin measurements, two new variables for spin determination
and an asymmetry for the determination of the couplings of the new particles
are introduced. It is shown that these observables allow one to independently
determine the spin and the couplings of the new particles, except for a few
cases that turn out to be indistinguishable at the LHC. These findings are
corroborated by results of an alternative analysis strategy based on an
automated likelihood test.Comment: 18 pages, 3 figures, LaTe
Spin and Chirality Effects in Antler-Topology Processes at High Energy Colliders
We perform a model-independent investigation of spin and chirality
correlation effects in the antler-topology processes
at high energy colliders with polarized
beams. Generally the production process
can occur not only through the -channel exchange of vector bosons,
, including the neutral Standard Model (SM) gauge bosons,
and , but also through the - and -channel exchanges of new
neutral states, and , and the -channel
exchange of new doubly-charged states, . The general set of
(non-chiral) three-point couplings of the new particles and leptons allowed in
a renormalizable quantum field theory is considered. The general spin and
chirality analysis is based on the threshold behavior of the excitation curves
for pair production in collisions with
longitudinal and transverse polarized beams, the angular distributions in the
production process and also the production-decay angular correlations. In the
first step, we present the observables in the helicity formalism. Subsequently,
we show how a set of observables can be designed for determining the spins and
chiral structures of the new particles without any model assumptions. Finally,
taking into account a typical set of approximately chiral invariant scenarios,
we demonstrate how the spin and chirality effects can be probed experimentally
at a high energy collider.Comment: 50 pages, 14 figures, 6 tables, matches version published in EPJ
Reach the Bottom Line of the Sbottom Search
We propose a new search strategy for directly-produced sbottoms at the LHC
with a small mass splitting between the sbottom and its decayed stable
neutralino. Our search strategy is based on boosting sbottoms through an
energetic initial state radiation jet. In the final state, we require a large
missing transverse energy and one or two b-jets besides the initial state
radiation jet. We also define a few kinematic variables to further increase the
discovery reach. For the case that the sbottom mainly decays into the bottom
quark and the stable neutralino, we have found that even for a mass splitting
as small as 10 GeV sbottoms with masses up to around 400 GeV can be excluded at
the 95% confidence level with 20 inverse femtobarn data at the 8 TeV LHC.Comment: 16 pages, 6 figure
Missing Momentum Reconstruction and Spin Measurements at Hadron Colliders
We study methods for reconstructing the momenta of invisible particles in
cascade decay chains at hadron colliders. We focus on scenarios, such as SUSY
and UED, in which new physics particles are pair produced. Their subsequent
decays lead to two decay chains ending with neutral stable particles escaping
detection. Assuming that the masses of the decaying particles are already
measured, we obtain the momenta by imposing the mass-shell constraints. Using
this information, we develop techniques of determining spins of particles in
theories beyond the standard model. Unlike the methods relying on Lorentz
invariant variables, this method can be used to determine the spin of the
particle which initiates the decay chain. We present two complementary ways of
applying our method by using more inclusive variables relying on kinematic
information from one decay chain, as well as constructing correlation variables
based on the kinematics of both decay chains in the same event.Comment: Version to appear in JHE
Spread Supersymmetry
In the multiverse the scale of SUSY breaking, \tilde{m} = F_X/M_*, may scan
and environmental constraints on the dark matter density may exclude a large
range of \tilde{m} from the reheating temperature after inflation down to
values that yield a LSP mass of order a TeV. After selection effects, the
distribution for \tilde{m} may prefer larger values. A single environmental
constraint from dark matter can then lead to multi-component dark matter,
including both axions and the LSP, giving a TeV-scale LSP lighter than the
corresponding value for single-component LSP dark matter.
If SUSY breaking is mediated to the SM sector at order X^* X, only squarks,
sleptons and one Higgs doublet acquire masses of order \tilde{m}. The gravitino
mass is lighter by a factor of M_*/M_Pl and the gaugino masses are suppressed
by a further loop factor. This Spread SUSY spectrum has two versions; the
Higgsino masses are generated in one from supergravity giving a wino LSP and in
the other radiatively giving a Higgsino LSP. The environmental restriction on
dark matter fixes the LSP mass to the TeV domain, so that the squark and
slepton masses are order 10^3 TeV and 10^6 TeV in these two schemes. We study
the spectrum, dark matter and collider signals of these two versions of Spread
SUSY. The Higgs is SM-like and lighter than 145 GeV; monochromatic photons in
cosmic rays arise from dark matter annihilations in the halo; exotic short
charged tracks occur at the LHC, at least for the wino LSP; and there are the
eventual possibilities of direct detection of dark matter and detailed
exploration of the TeV-scale states at a future linear collider. Gauge coupling
unification is as in minimal SUSY theories.
If SUSY breaking is mediated at order X, a much less hierarchical spectrum
results---similar to that of the MSSM, but with the superpartner masses 1--2
orders of magnitude larger than in natural theories.Comment: 20 pages, 5 figure
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