1,232 research outputs found
How to erase surface plasmon fringes
We report the realization of a dual surface plasmon polariton (SPP)
microscope based on leakage radiation (LR) analysis. The microscope can either
image SPP propagation in the direct space or tin the Fourier space. This
particularity allows in turn manipulation of the LR image for a clear
separation of different interfering SPP contributions present close to optical
nanoelements.Comment: Appl. Phys. Lett. 89, 091117 (2006
Drop impact upon micro- and nanostructured superhydrophobic surfaces
We experimentally investigate drop impact dynamics onto different
superhydrophobic surfaces, consisting of regular polymeric micropatterns and
rough carbon nanofibers, with similar static contact angles. The main control
parameters are the Weber number \We and the roughness of the surface. At small
\We, i.e. small impact velocity, the impact evolutions are similar for both
types of substrates, exhibiting Fakir state, complete bouncing, partial
rebouncing, trapping of an air bubble, jetting, and sticky vibrating water
balls. At large \We, splashing impacts emerge forming several satellite
droplets, which are more pronounced for the multiscale rough carbon nanofiber
jungles. The results imply that the multiscale surface roughness at nanoscale
plays a minor role in the impact events for small \We \apprle 120 but an
important one for large \We \apprge 120. Finally, we find the effect of
ambient air pressure to be negligible in the explored parameter regime \We
\apprle 150Comment: 8 pages, 7 figure
Qualitätsprodukt Erziehungsberatung. Empfehlungen zu Leistungen, Qualitätsmerkmalen und Kennziffern
Neben einer Beschreibung der Leistung Erziehungs- und Familienberatung - Beratung und Therapie, präventive Angebote und Vernetzungsaktivitäten - werden ihre Qualitätsmerkmale - gegliedert nach Struktur-, Prozess- und Ergebnisqualität - ausführlich dargestellt und Kennziffern zu ihrer quantitativen Erfassung vorgeschlagen. Der Anhang enthält u.a. eine Kurzfassung der vorliegenden Empfehlungen zu Leistungen, Qualitätsmerkmalen und Kennziffern. (DIPF/Autor
Anomalies and WZW-term of two-flavour QCD
The U(2)_R x U(2)_L symmetry of QCD with two massless flavours is subject to
anomalies which affect correlation functions involving the singlet currents
A^0_\mu or V^0_\mu. These are relevant for pion-photon interactions, because -
for two flavours - the electromagnetic current contains a singlet piece. We
give the effective Lagrangian required for the corresponding low energy
analysis to next-to-leading order, without invoking an expansion in the mass of
the strange quark. In particular, the Wess-Zumino-Witten term that accounts for
the two-flavour anomalies within the effective theory is written down in closed
form.Comment: 17 pages, 1 figur
Muon Physics: A Pillar of the Standard Model
Since its discovery in the 1930s, the muon has played an important role in
our quest to understand the sub-atomic theory of matter. The muon was the first
second-generation standard-model particle to be discovered, and its decay has
provided information on the (Vector -Axial Vector) structure of the weak
interaction, the strength of the weak interaction, G_F, and the conservation of
lepton number (flavor) in muon decay. The muon's anomalous magnetic moment has
played an important role in restricting theories of physics beyond the standard
standard model, where at present there is a 3.4 standard-deviation difference
between the experiment and standard-model theory. Its capture on the atomic
nucleus has provided valuable information on the modification of the weak
current by the strong interaction which is complementary to that obtained from
nuclear beta decay.Comment: 8 pages, 9 figures. Invited paper for the Journal of Physical Society
in Japan (JPSJ), Special Topics Issue "Frontiers of Elementary Particle
Physics, The Standard Model and beyond
The quark loop calculation of the gamma -> 3 pi form factor
The presently experimentally interesting form factor for the anomalous
process gamma -> pi^+ pi^0 pi^- is calculated as the quark "box"-amplitude
where the intermediate fermion loop is the one of constituent quarks with the
pseudoscalar coupling to pions. This also corresponds to the form factor, in
the lowest order in pion interactions, of the sigma-model and of the chiral
quark model. We give the analytic expression for the form factor in terms of an
expansion in the pion momenta up to the order O(p^8) relative to the soft point
result, and also perform its exact numerical evaluation. We compare our
predictions with those of the vector meson dominance and chiral perturbation
theory, as well as with the scarce data available so far.Comment: revtex, 12 pages including 3 eps figure
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