2,805 research outputs found
Why the Water Bridge does not collapse
In 2007 an interesting phenomenon was discovered: a thread of water, the
so-called water bridge (WB), can hang between two glass beakers filled with
deionized water if voltage is applied to them. We analyze the available
explanations of the WB stability and propose a completely different one: the
force that supports the WB is the surface tension of water and the role of
electric field is not to allow the WB to reduce its surface energy by means of
breaking into separate drops.Comment: 4 pages, 3 figure
Gauge/Anomaly Syzygy and Generalized Brane World Models of Supersymmetry Breaking
In theories in which SUSY is broken on a brane separated from the MSSM matter
fields, supersymmetry breaking is naturally mediated in a variety of ways.
Absent other light fields in the theory, gravity will mediate supersymmetry
breaking through the conformal anomaly. If gauge fields propagate in the extra
dimension they, too, can mediate supersymmetry breaking effects. The presence
of gauge fields in the bulk motivates us to consider the effects of new
messenger fields with holomorphic and non-holomorphic couplings to the
supersymmetry breaking sector. These can lead to contributions to the soft
masses of MSSM fields which dramatically alter the features of brane world
scenarios of supersymmetry breaking. In particular, they can solve the negative
slepton mass squared problem of anomaly mediation and change the predictions of
gaugino mediation.Comment: 4 pages, RevTe
Late Reheating, Hadronic Jets and Baryogenesis
If inflaton couples very weakly to ordinary matter the reheating temperature
of the universe can be lower than the electroweak scale. In this letter we show
that the late reheating occurs in a highly non-uniform way, within narrow areas
along the jets produced by ordinary particles originated from inflaton decays.
Depending on inflaton mass and decay constant, the initial temperature inside
the lumps of the overheated plasma may be large enough to trigger the
unsuppressed sphaleron processes with baryon number non-conservation, allowing
for efficient local electroweak baryogenesis.Comment: 4 pages, 2 figures, revtex
Higgs Boson Exempt No-Scale Supersymmetry and its Collider and Cosmology Implications
One of the most straightforward ways to address the flavor problem of
low-energy supersymmetry is to arrange for the scalar soft terms to vanish
simultaneously at a scale much larger than the electroweak scale. This
occurs naturally in a number of scenarios, such as no-scale models, gaugino
mediation, and several models with strong conformal dynamics. Unfortunately,
the most basic version of this approach that incorporates gaugino mass
unification and zero scalar masses at the grand unification scale is not
compatible with collider and dark matter constraints. However, experimental
constraints can be satisfied if we exempt the Higgs bosons from flowing to zero
mass value at the high scale. We survey the theoretical constructions that
allow this, and investigate the collider and dark matter consequences. A
generic feature is that the sleptons are relatively light. Because of this,
these models frequently give a significant contribution to the anomalous
magnetic moment of the muon, and neutralino-slepton coannihilation can play an
important role in obtaining an acceptable dark matter relic density.
Furthermore, the light sleptons give rise to a large multiplicity of lepton
events at colliders, including a potentially suggestive clean trilepton signal
at the Tevatron, and a substantial four lepton signature at the LHC.Comment: 36 pages, 16 figure
Lepton Flavor Violation and Supersymmetric Dirac Leptogenesis
Dirac leptogenesis (or Dirac neutrinogenesis), in which neutrinos are purely
Dirac particles, is an interesting alternative to the standard leptogenesis
scenario. In its supersymmetric version, the modified form of the
superpotential required for successful baryogenesis contributes new,
generically non-flavor-diagonal terms to the slepton and sneutrino mass
matrices. In this work, we examine how current experimental bounds on
flavor-changing effects in the lepton sector (and particularly the bound on Mu
-> e Gamma) constrain Dirac leptogenesis and we find that it is capable of
succeeding with superpartner masses as low as 100 GeV. For such light scalars
and electroweakinos, upcoming experiments such as MEG are generically expected
to observe signals of lepton flavor violation.Comment: 15 pages, 4 figures, corrected parametric dependance on leading LFV
term, figure 2 and discussion modified accordingly, conclusions unchange
Relativistic Turbulence: A Long Way from Preheating to Equilibrium
We study, both numerically and analytically, the development of equilibrium
after preheating. We show that the process is characterised by the appearance
of Kolmogorov spectra and the evolution towards thermal equilibrium follows
self-similar dynamics. Simplified kinetic theory gives values for all
characteristic exponents which are close to what is observed in lattice
simulations. The resulting time for thermalization is long, and temperature at
thermalization is low, eV in the simple
inflationary model. Our results allow a straightforward generalization to
realistic models.Comment: 4 pages, 3figures, LaTe
Implications of gauge-mediated supersymmetry breaking with vector-like quarks and a ~125 GeV Higgs boson
We investigate the implications of models that achieve a Standard Model-like
Higgs boson of mass near 125 GeV by introducing additional TeV-scale
supermultiplets in the vector-like 10+\bar{10} representation of SU(5), within
the context of gauge-mediated supersymmetry breaking. We study the resulting
mass spectrum of superpartners, comparing and contrasting to the usual
gauge-mediated and CMSSM scenarios, and discuss implications for LHC
supersymmetry searches. This approach implies that exotic vector-like fermions
t'_{1,2}, b',and \tau' should be within the reach of the LHC. We discuss the
masses, the couplings to electroweak bosons, and the decay branching ratios of
the exotic fermions, with and without various unification assumptions for the
mass and mixing parameters. We comment on LHC prospects for discovery of the
exotic fermion states, both for decays that are prompt and non-prompt on
detector-crossing time scales.Comment: 32 pages. v2: references added, figure caption 5.3 correcte
Anomaly mediated supersymmetry breaking and its test in linear colliders
Signatures of anomaly mediated supersymmetry breaking in linear colliders are
briefly reviewed after presenting an outline of the theoretical framework. A
unique and distinct feature of a large class of models of this type is a
winolike chargino which is very closely degenerate in mass with the lightest
neutralino. The very slow decay of this chargino results in a heavily ionizing
charged track and one soft charged pion with a characteristic momentum
distribution, leading to unique signals in linear colliders which are
essentially free of background. The determination of chargino and slepton
masses from such events is a distinctly interesting possibility.Comment: 15 pages, LaTex, 4 PS figures, ws-mpla.cls file included. One
reference added. To appear as a Brief Review in Modern Physics Letters
Chronic bacterial prostatitis: efficacy of short-lasting antibiotic therapy with prulifloxacin (Unidrox®) in association with saw palmetto extract, lactobacillus sporogens and arbutin (Lactorepens®)
Bacterial prostatitis (BP) is a common condition accounting responsible for about 5-10% of all prostatitis cases; chronic bacterial prostatitis (CBP) classified as type II, are less common but is a condition that significantly hampers the quality of life, (QoL) because not only is it a physical condition but also a psychological distress. Commonly patients are treated with antibiotics alone, and in particular fluoroquinolones are suggested by the European Urology guidelines. This approach, although recommended, may not be enough. Thus, a multimodal approach to the prolonged antibiotic therapy may be helpful.210 patients affected by chronic bacterial prostatitis were enrolled in the study. All patients were positive to Meares-Stamey test and symptoms duration was > 3 months. The purpose of the study was to evaluate the efficacy of a long lasting therapy with a fluoroquinolone in association with a nutraceutical supplement (prulifloxacin 600 mg for 21 days and an association of Serenoa repens 320 mg, Lactobacillus Sporogens 200 mg, Arbutin 100 mg for 30 days). Patients were randomized in two groups (A and B) receiving respectively antibiotic alone and an association of antibiotic plus supplement.Biological recurrence at 2 months in Group A was observed in 21 patients (27.6%) and in Group B in 6 patients (7.8%). Uropathogens found at the first follow-up were for the majority Gram - (E. coli and Enterobacter spp.). A statistically significant difference was found at the time of the follow-up between Group A and B in the NIH-CPSI questionnaire score, symptoms evidence and serum PSA.Broad band, short-lasting antibiotic therapy in association with a nutritional supplement (serenoa repens, lactobacillus sporogens and arbutin) show better control and recurrence rate on patients affected by chronic bacterial prostatitits in comparison with antibiotic treatment alone.NCT02130713Date of trial Registration: 30/04/2014
Reheating Temperature and Inflaton Mass Bounds from Thermalization After Inflation
We consider the conditions for the decay products of perturbative inflaton
decay to thermalize. The importance of considering the full spectrum of
inflaton decay products in the thermalization process is emphasized. It is
shown that the delay between the end of inflaton decay and thermalization
allows the thermal gravitino upper bound on the reheating temperature to be
raised from 10^{8} GeV to as much as 10^{12} GeV in realistic inflation models.
Requiring that thermalization occurs before nucleosynthesis imposes an upper
bound on the inflaton mass as a function of the reheating temperature, m_{S} <
10^{10} (T_{R}/1 GeV)^{7/9} GeV. It is also shown that even in realistic
inflation models with relatively large reheating temperatures, it is
non-trivial to have thermalization before the electroweak phase transition
temperature. Therefore the thermal history of the Universe is very sensitive to
details of the inflation model.Comment: 12 Pages LaTeX. Catalysed thermalization discussion correcte
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