182,409 research outputs found
Possibility of observing MSSM charged Higgs in association with a W boson at LHC
Possibility of observing associated production of charged Higgs and W boson
in the framework of MSSM at LHC is studied. Both leptonic and hadronic decays
of W boson are studied while the charged Higgs boson is considered to decay to
a lepton and a neutrino. Therefore two search categories are defined
based on the leptonic and hadronic final states, i.e.
and where or and is a light jet from
decay. The discovery chance of the two categories is evaluated at an
integrated luminosity of 300 \invfb at LHC. It is shown that both leptonic and
hadronic final states have the chance of discovery at high \tanb. Finally
and contours are provided for both search categories.Comment: 20 pages, 19 figure
Symmetry-preserving Observers
This paper presents three non-linear observers on three examples of
engineering interest: a chemical reactor, a non-holonomic car, and an inertial
navigation system. For each example, the design is based on physical
symmetries. This motivates the theoretical development of invariant observers,
i.e, symmetry-preserving observers. We consider an observer to consist in a
copy of the system equation and a correction term, and we give a constructive
method (based on the Cartan moving-frame method) to find all the
symmetry-preserving correction terms. They rely on an invariant frame (a
classical notion) and on an invariant output-error, a less standard notion
precisely defined here. For each example, the convergence analysis relies also
on symmetries consideration with a key use of invariant state-errors. For the
non-holonomic car and the inertial navigation system, the invariant
state-errors are shown to obey an autonomous differential equation independent
of the system trajectory. This allows us to prove convergence, with almost
global stability for the non-holonomic car and with semi-global stability for
the inertial navigation system. Simulations including noise and bias show the
practical interest of such invariant asymptotic observers for the inertial
navigation system.Comment: To be published in IEEE Automatic Contro
Do the gravitational corrections to the beta functions of the quartic and Yukawa couplings have an intrinsic physical meaning?
We study the beta functions of the quartic and Yukawa couplings of General
Relativity and Unimodular Gravity coupled to the and Yukawa
theories with masses. We show that the General Relativity corrections to those
beta functions as obtained from the 1PI functional by using the standard MS
multiplicative renormalization scheme of Dimensional Regularization are gauge
dependent and, further, that they can be removed by a non-multiplicative,
though local, field redefinition. An analogous analysis is carried out when
General Relativity is replaced with Unimodular Gravity. Thus we show that any
claim made about the change in the asymptotic behaviour of the quartic and
Yukawa couplings made by General Relativity and Unimodular Gravity lack
intrinsic physical meaning.Comment: 6 pages, 7 figure
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When adolescents stop psychological therapy: rupture-repair in the therapeutic alliance and association with therapy ending
therapeutic alliance consistently predicts dropout from psychological therapy, and ruptures in the therapeutic alliance may also predict dropout, yet there is a dearth
of research with adolescents. This study investigated whether markers of rupturerepair in the therapeutic alliance were indicative of different types of treatment ending in adolescents who received psychological treatment for depression. Data were from the IMPACT study, a trial investigating the effectiveness of therapies for adolescent depression. Participants were randomly allocated to receive a psychological therapy: Brief Psychosocial Intervention, Cognitive-Behavioural Therapy or Short-Term Psychoanalytic Psychotherapy. The sample (N=35) comprised adolescents who had either completed their treatment (n=14) or dropped out (n=21) according to their therapist. Dropout cases were further classified as dissatisfied (n=14) or got-whatthey-
needed (n=7) based on post-therapy interviews with the adolescent and therapist. Selected audio-recordings of therapy sessions were rated using the Rupture Resolution Rating System and Working Alliance Inventory (observer-version). Therapeutic alliance and rupture-repair during therapy were similar for completers and got-what-they-needed dropouts, while dissatisfied dropouts had poorer
therapeutic alliance, more ruptures, ruptures were frequently unresolved, and therapists contributed to ruptures to a greater extent. Qualitative analysis of the sessions led to the construction of three categories of therapist contribution to
ruptures: therapist minimal response; persisting with a therapeutic activity; and focus on risk. Results suggest that ruptures, especially when unresolved, could be regarded
as warning signs of disengagement and dropout from psychological treatment. Future research should investigate how ruptures may be effectively identified and resolved in
treatment with adolescents
Identifying capacitive and inductive loss in lumped element superconducting hybrid titanium nitride/aluminum resonators
We present a method to systematically locate and extract capacitive and
inductive losses in superconducting resonators at microwave frequencies by use
of mixed-material, lumped element devices. In these devices, ultra-low loss
titanium nitride was progressively replaced with aluminum in the
inter-digitated capacitor and meandered inductor elements. By measuring the
power dependent loss at 50 mK as the Al-TiN fraction in each element is
increased, we find that at low electric field, i.e. in the single photon limit,
the loss is two level system in nature and is correlated with the amount of Al
capacitance rather than the Al inductance. In the high electric field limit,
the remaining loss is linearly related to the product of the Al area times its
inductance and is likely due to quasiparticles generated by stray radiation. At
elevated temperature, additional loss is correlated with the amount of Al in
the inductance, with a power independent TiN-Al interface loss term that
exponentially decreases as the temperature is reduced. The TiN-Al interface
loss is vanishingly small at the 50 mK base temperature.Comment: 10 pages, 5 figure
On the evidence for brown-dwarf secondary stars in cataclysmic variables
We present the K-band spectrum of the cataclysmic variable LL And, obtained
using NIRSPEC on Keck-II. The spectrum shows no evidence for the absorption
features observed by Howell & Ciardi (2001), which these authors used to claim
a detection of a brown-dwarf secondary star in LL And. In light of our new
data, we review the evidence for brown-dwarf secondary stars in this and other
cataclysmic variables.Comment: 6 pages, to appear in Monthly Notices, accepte
Identifying Sneutrino Dark Matter: Interplay between the LHC and Direct Search
Under R-parity, the lightest supersymmetric particle (LSP) is stable and may
serve as a good dark matter candidate. The R-parity can be naturally introduced
with a gauge origin at TeV scale. We go over why a TeV scale B-L gauge
extension of the minimal supersymmetric standard model (MSSM) is one of the
most natural, if not demanded, low energy supersymmetric models. In the
presence of a TeV scale Abelian gauge symmetry, the (predominantly)
right-handed sneutrino LSP can be a good dark matter candidate. Its
identification at the LHC is challenging because it does not carry any standard
model charge. We show how we can use the correlation between the LHC
experiments (dilepton resonance signals) and the direct dark matter search
experiments (such as CDMS and XENON) to identify the right-handed sneutrino LSP
dark matter in the B-L extended MSSM.Comment: 5 pages, 3 figure
The influence of a local wall deformation on the development of natural instabilities in a laminar boundary layer
The natural instabilities which propagate in the laminar boundary layer of a flat plate composed of intermittent wave trains are described. A spectral analysis determines the frequency range and gives a frequency and the harmonic 2 only if there is a wall deformation. This analysis provides the amplitude modulation spectrum of the instabilities. Plots of the evolution of power spectral density are compared with the numerical results obtained from the resolve of the Orr-Sommerfeld equation, while the harmonic is related to a micro-recirculating flow near the wall deformation
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