9,152 research outputs found
Low computational complexity mode division multiplexed OFDM transmission over 130 km of few mode fiber
We demonstrate 337.5-Gb/s MDM-8QAM-OFDM transmission over 130 km of FMF. This confirms that OFDM can significantly reduce the required DSP complexity to compensate for differential mode delay, a key step towards real-time MDM transmission
Equilibration in Quark Gluon Plasma
The hydrodynamic expansion rate of quark gluon plasma (QGP) is evaluated and
compared with the scattering rate of quarks and gluons within the system.
Partonic scattering rates evaluated within the ambit of perturbative Quantum
Choromodynamics (pQCD) are found to be smaller than the expansion rate
evaluated with ideal equation of state (EoS) for the QGP. This indicate that
during the space-time evolution the system remains out of equilibrium.
Enhancement of pQCD cross sections and a more realistic EoS keep the partons
closer to the equilibrium.Comment: To be published in the Quark Matter 2008 poster proceeding
Low energy consequences from supersymmetric models with left-right symmetry
We consider several low energy consequences arising from a class of
supersymmetric models based on the gauge groups and in which the gauge
hierarchy and problems have been resolved. There are important
constraints on the MSSM parameters , and
, and we discuss how they are reconciled with radiative electroweak
breaking. We also consider the ensuing sparticle and Higgs spectroscopy, as
well as the decays and . The latter process
may be amenable to experimental tests through an order of magnitude increase in
sensitivity.Comment: 17 pages, latex2
Optimization of thermoluminescence response of copper doped zinc lithium borate glass co-doped with Na2O
Establishing the basic procedures that will influence the enhancement of the TL yield of a phosphor is paramount in the issue of dosimetry. Melt quenching method was adopted in synthesizing lithium borate glass modified with ZnO, doped with CuO and codoped with Na2O. The structural and optical properties of zinc lithium borate and some TL properties of copper doped zinc lithium borate were reported in our previous works. The amorphous nature of the prepared glasses was confirmed by x-ray diffraction analysis (XRD). Physical properties of the glass were obtained via Archimedes principle. The copper doped zinc lithium borate was co-doped with different concentration of Na2O (0.025 mol % to 0.1 mol %). The glasses were irradiated with 4 Gy dose of gamma rays using 60Co gamma cell. The highest TL response was recorded against 0.05 mol% concentration of Na2O. The best settings for TLD reading of the proposed TLD were determined. The optimal annealing temperature and time for this composition was found to be 300 oC and 50 min respectively. The best heating rate at which the new TLD can be readout was 3 oC S-1
The Promising Process to Distinguish Supersymmetric Models with Large tan from the Standard Model:
It is shown that in supersymmetric models (SUSYMs) the large supersymmetric
contributions to come from the Feynman diagrams
which consist of exchanging neutral Higgs bosons (NHBs) and the chargino-stop
loop and are proportional to tan when tan
is large and the mass of the lightest neutral Higgs boson m is not too
large (say, less than 150 Gev). Numerical results show that the branching
ratios of can be enhanced by more than 100%
compared to the standard model (SM) and the backward-forward asymmetry of
lepton is significantly different from that in SM when tan.Comment: 8 pages, including 2 figure
Gravity on codimension 2 brane worlds
We compute the matching conditions for a general thick codimension 2 brane, a
necessary previous step towards the investigation of gravitational phenomena in
codimension 2 braneworlds. We show that, provided the brane is weakly curved,
they are specified by the integral in the extra dimensions of the brane
energy-momentum, independently of its detailed internal structure. These
general matching conditions can then be used as boundary conditions for the
bulk solution. By evaluating Einstein equations at the brane boundary we are
able to write an evolution equation for the induced metric on the brane
depending only on physical brane parameters and the bulk energy-momentum
tensor. We particularise to a cosmological metric and show that a realistic
cosmology can be obtained in the simplest case of having just a non-zero
cosmological constant in the bulk. We point out several parallelisms between
this case and the codimension 1 brane worlds in an AdS space.Comment: 24 page
``Non-factorizable'' terms in hadronic B-meson weak decays
The branching ratios for the hadronic B-meson weak decays B -> J/psi K and B
-> D pi are used to extract the size of the ``non-factorizable'' terms in the
decay amplitudes. It is pointed out that the solutions are not uniquely
determined. In the B -> J/psi K case, a 2-fold ambiguity can be removed by
analyzing the contribution of this decay to B -> K l+ l-. In the B -> D pi
case, a 4-fold ambiguity can only be removed if the ``non-factorizable'' terms
are assumed to be a small correction to the vacuum insertion result.Comment: 15 pages (and 1 figure, available upon request), TRIUMF report no.
TRI-PP-94-7
Photons from Quark Gluon Plasma and Hot Hadronic Matter
The productions of real photons from quark gluon plasma and hot hadronic
matter formed after the nucleus - nucleus collisions at ultra-relativistic
energies are discussed. The effects of the spectral shift of the hadrons at
finite temperature on the production of photons are investigated. On the basis
of the present analysis it is shown that the photon spectra measured by WA98
collaboration in Pb + Pb collisions at CERN SPS energies can be explained by
both QGP as well as hadronic initial states if the spectral shift of hadrons at
finite temperature is taken into account. Several other works on the analysis
of WA98 photon data have also been briefly discussed.Comment: Latex file, six eps figures include
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