704 research outputs found
Effect of Minimal lengths on Electron Magnetism
We study the magnetic properties of electron in a constant magnetic field and
confined by a isotropic two dimensional harmonic oscillator on a space where
the coordinates and momenta operators obey generalized commutation relations
leading to the appearance of a minimal length. Using the momentum space
representation we determine exactly the energy eigenvalues and eigenfunctions.
We prove that the usual degeneracy of Landau levels is removed by the presence
of the minimal length in the limits of weak and strong magnetic field.The
thermodynamical properties of the system, at high temperature, are also
investigated showing a new magnetic behavior in terms of the minimal length.Comment: 14 pages, 1 figur
Elliptic Flow, Initial Eccentricity and Elliptic Flow fluctuations in Heavy Ion Collisions at RHIC
We present measurements of elliptic flow and event-by-event fluctuations
established by the PHOBOS experiment. Elliptic flow scaled by participant
eccentricity is found to be similar for both systems when collisions with the
same number of participants or the same particle area density are compared. The
agreement of elliptic flow between Au+Au and Cu+Cu collisions provides evidence
that the matter is created in the initial stage of relativistic heavy ion
collisions with transverse granularity similar to that of the participant
nucleons. The event-by-event fluctuation results reveal that the initial
collision geometry is translated into the final state azimuthal particle
distribution, leading to an event-by-event proportionality between the observed
elliptic flow and initial eccentricity.Comment: To appear in the proceedings of the Lake Louise Winter Institute
2007. The proceedings of the institute will be published by World Scientifi
Study of the Fusion-Fission Process in the Reaction
Fusion-fission and fully energy-damped binary processes of the
Cl+Mg reaction were investigated using particle-particle
coincidence techniques at a Cl bombarding energy of E
8 MeV/nucleon. Inclusive data were also taken in order to determine the partial
wave distribution of the fusion process. The fragment-fragment correlation data
show that the majority of events arises from a binary-decay process with a
relatively large multiplicity of secondary light-charged particles emitted by
the two primary excited fragments in the exit channel. No evidence is observed
for ternary-breakup processes, as expected from the systematics recently
established for incident energies below 15 MeV/nucleon and for a large number
of reactions. The binary-process results are compared with predictions of
statistical-model calculations. The calculations were performed using the
Extended Hauser-Feshbach method, based on the available phase space at the
scission point of the compound nucleus. This new method uses
temperature-dependent level densities and its predictions are in good agreement
with the presented experimental data, thus consistent with the fusion-fission
origin of the binary fully-damped yields.Comment: 30 pages standard REVTeX file, 10 eps Figures; to be published at the
European Physical Journal A - Hadrons and Nucle
Entropy of the Randall-Sundrum black brane world to all orders in the Planck length
We study the effects, to all orders in the Planck length from a generalized
uncertainty principle (GUP), on the statistical entropy of massive scalar bulk
fields in the Randall-Sundrum black brane world. We show that the
Bekenstein-Hawking area law is not preserved, and contains small corrections
terms proportional to the black hole inverse area.Comment: 19 pages, 1 figure. (v2): section 4 improve
Deformation effects in the Si+C and Si+Si reaction Search
The possible occurence of highly deformed configurations is investigated in
the Ca and Ni di-nuclear systems as formed in the
Si+C,Si reactions by using the properties of emitted light
charged particles. Inclusive as well as exclusive data of the heavy fragments
and their associated light charged particles have been collected by using the
{\sc ICARE} charged particle multidetector array. The data are analysed by
Monte Carlo CASCADE statistical-model calculations using a consistent set of
parameters with spin-dependent level densities. Significant deformation effects
at high spin are observed as well as an unexpected large Be cluster
emission of a binary nature.Comment: 3 pages latex, 2 eps figures, paper presented in "wokshop on physics
with multidetector array (pmda2000)Calcutta, India (to be published at
PRAMANA, journal of Physics, India
Status and overview of development of the Silicon Pixel Detector for the PHENIX experiment at the BNL RHIC
We have developed a silicon pixel detector to enhance the physics
capabilities of the PHENIX experiment. This detector, consisting of two layers
of sensors, will be installed around the beam pipe at the collision point and
covers a pseudo-rapidity of | \eta | < 1.2 and an azimuth angle of | \phi | ~
2{\pi}. The detector uses 200 um thick silicon sensors and readout chips
developed for the ALICE experiment. In order to meet the PHENIX DAQ readout
requirements, it is necessary to read out 4 readout chips in parallel. The
physics goals of PHENIX require that radiation thickness of the detector be
minimized. To meet these criteria, the detector has been designed and
developed. In this paper, we report the current status of the development,
especially the development of the low-mass readout bus and the front-end
readout electronics.Comment: 9 pages, 8 figures and 1 table in DOCX (Word 2007); PIXEL 2008
workshop proceedings, will be published in the Proceedings Section of
JINST(Journal of Instrumentation
Black hole thermodynamics with generalized uncertainty principle
In the standard viewpoint, the temperature of a stationary black hole is
proportional to its surface gravity, . This is a
semiclassical result and the quantum gravity effects are not taken into
consideration. This Letter explores a unified expression for the black hole
temperature in the sense of a generalized uncertainty principle(GUP). Our
discussion involves a heuristic analysis of a particle which is absorbed by the
black hole. Besides a class of static and spherically symmetric black holes, an
axially symmetric Kerr-Newman black hole is considered. Different from the
existing literature, we suggest that the black hole's irreducible mass
represent the characteristic size in the absorption process. The information
capacity of a remnant is also discussed by Bousso's D-bound in de Sitter
spacetime.Comment: 18 pages, great improvement on the first version; a Kerr-Newman black
hole is considere
- …
