6,074 research outputs found
Top Notch Support for eBooks
Come learn tips and tricks for delivering top notch technical support for eBooks. Library staff are the front line technical support for a growing number of patrons with diverse technical abilities wanting to access eBooks. We’ll share VPL’s unique team approach and innovative techniques for delivering technical support for your eBook collection. In this session, participants will learn:
How to apply reference interview skills to technical support.
How to create effective tools to use with patrons, including templates and on-the-spot screencasts.
How to build an effective ebook-support team in your reference departmen
Charged LFV in a low-scale seesaw mSUGRA model
We investigate the influence of the boundary conditions of minimal
supergravity (mSUGRA) on the supersymmetric mechanism for lepton flavour
violation (LFV) proposed recently [1], within the framework of the MSSM
extended by TeV-scale singlet heavy neutrinos. We find that the consideration
of the mSUGRA boundary condition may increase the branching ratios of the muon
and tauon decaying into three charged leptons by up to a factor of 5, whereas
the corresponding branching ratio for their photonic decays remains almost
unchanged.Comment: 6 pages, 3 figures. Prepared for the Proceedings of the 11th
International Workshop on Tau Lepton Physics, Manchester, UK, September
13-17, 2010. Presented by A. Ilakova
Fine guidance for a spaceborne telescope
Two transparent plates are mounted at equal and opposite angles in secondary optical-system housing, angles being set for optimum astigmatism correction. Rotation of secondary housing assembly and translation of detector are proportional to angular position of secondary image. Combined movement of two retains image within sagittal foci of secondary system
Ritchey-Chretien Telescope
A Ritchey-Chretien telescope is described which was designed to respond to images located off the optical axis by using two transparent flat plates positioned in the ray path of the image. The flat plates have a tilt angle relative to the ray path to compensate for astigmatism introduced by the telescope. The tilt angle of the plates is directly proportional to the off axis angle of the image. The plates have opposite inclination angles relative to the ray paths. A detector which is responsive to the optical image as transmitted through the plates is positioned approximately on the sagittal focus of the telescope
RNase H enables efficient repair of R-loop induced DNA damage.
R-loops, three-stranded structures that form when transcripts hybridize to chromosomal DNA, are potent agents of genome instability. This instability has been explained by the ability of R-loops to induce DNA damage. Here, we show that persistent R-loops also compromise DNA repair. Depleting endogenous RNase H activity impairs R-loop removal in Saccharomyces cerevisiae, causing DNA damage that occurs preferentially in the repetitive ribosomal DNA locus (rDNA). We analyzed the repair kinetics of this damage and identified mutants that modulate repair. We present a model that the persistence of R-loops at sites of DNA damage induces repair by break-induced replication (BIR). This R-loop induced BIR is particularly susceptible to the formation of lethal repair intermediates at the rDNA because of a barrier imposed by RNA polymerase I
Mode hopping strongly affects observability of dynamical instability in optical parametric oscillators
Theoretical investigations of dynamical behavior in optical parametric
oscillators (OPO) have generally assumed that the cavity detunings of the
interacting fields are controllable parameters. However, OPOs are known to
experience mode hops, where the system jumps to the mode of lowest cavity
detuning. We note that this phenomenon significantly limits the range of
accessible detunings and thus may prevent instabilities predicted to occur
above a minimum detuning from being evidenced experimentally. As a simple
example among a number of instability mechanisms possibly affected by this
limitation, we discuss the Hopf bifurcation leading to periodic behavior in the
monomode mean-field model of a triply resonant OPO and show that it probably
can be observed only in very specific setups.Comment: submitted to Phys. Rev.
Comment on "the decoupling of heavy sneutrinos in low-scale seesaw models"
The authors of a recent communication [arXiv:1312.5318] claim to have traced
an error in the existing literature regarding the evaluation of the one-loop
right-handed sneutrino contributions to lepton-flavour-violating observables in
supersymmetric low-scale seesaw models. In this short note, we emphasize that
contrary to those authors' claim, our paper [arXiv:1212.5939] contains no such
a flaw, and both our analytical and numerical results exhibit the expected
decoupling property of the heavy sneutrinos in the Z-penguin graphs.Comment: 2 pages, 1 figur
Charged Lepton Flavour Violation in Supersymmetric Low-Scale Seesaw Models
We study charged lepton flavour violation in low-scale seesaw models of
minimal supergravity, which realize large neutrino Yukawa couplings thanks to
approximate lepton-number symmetries. There are two dominant sources of lepton
flavour violation in such models. The first source originates from the usual
soft supersymmetry-breaking sector, whilst the second one is entirely
supersymmetric and comes from the supersymmetric neutrino Yukawa sector. Within
the framework of minimal supergravity, we consider both sources of lepton
flavour violation, soft and supersymmetric, and calculate a number of possible
lepton-flavour-violating transitions, such as the photonic decays of muons and
taus, mu -> e gamma, tau -> e gamma and tau -> mu gamma, their neutrinoless
three-body decays, mu -> e e e, tau -> e e e, tau -> mu mu mu, tau -> e e mu
and tau -> e mu mu, and the coherent mu -> e conversion in nuclei. After taking
into account the exclusion bounds placed by present experiments of lepton
flavour violation, we derive combined theoretical limits on the universal heavy
Majorana mass scale mN and the light-to-heavy neutrino mixings. Supersymmetric
low-scale seesaw models offer distinct correlated predictions for
lepton-flavour-violating signatures, which might be discovered in current and
projected experiments, such as MEG, COMET/PRISM, Mu2e, super-BELLE and LHCb.Comment: 28 pages, 11 figures, comment added to conclusions, version as to
appear in Physical Review
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