36,380 research outputs found
Spherically confined isotropic harmonic oscillator
The generalized pseudospectral Legendre method is used to carry out accurate
calculations of eigenvalues of the spherically confined isotropic harmonic
oscillator with impenetrable boundaries. The energy of the confined state is
found to be equal to that of the unconfined state when the radius of
confinement is suitably chosen as the location of the radial nodes in the
unconfined state. This incidental degeneracy condition is numerically shown to
be valid in general. Further, the full set of pairs of confined states defined
by the quantum numbers [(n+1, \ell) ; (n, \ell+2)], n = 1,2,.., and with the
radius of confinement {(2 \ell +3)/2}^{1/2} a.u., which represents the single
node in the unconfined (1, \ell) state, is found to display a constant energy
level separation exactly given by twice the oscillator frequency. The results
of similar numerical studies on the confined Davidson oscillator with
impenetrable boundary as well as the confined isotropic harmonic oscillator
with finite potential barrier are also reported .The significance of the
numerical results are discussed.Comment: 28 pages, 4 figure
Effective String Theory Inspired Potential and Meson Masses in Higher Dimension
Nambu-Goto action in classical bosonic string model for hadrons predicts
quark-antiquark potential to be\cite{Nambu-Goto} . In this report we present studies of masses of heavy flavour mesons
in higher dimension with our recently developed wave functions obtained
following string inspired potential. We report the dimensional dependence of
the masses of mesons. Our results suggest that as the meson mass increases with
the number of extra spatial dimension, it will attain the Planck scale () asymptotically at an astronomically large spatial dimension (we
call it Planck dimension) , which sets the limit of
applicability of Schrodinger equation in large dimension
An Effective Cutoff for the Isolalated Lepton Background from Bottom Decay --
There is a strong correlation between the and isolation of the lepton
coming from decay. Consequently the isolated lepton background from
decay goes down rapidly with increasing lepton ; and there is a
cutoff beyond which it effectively vanishes. For the isolation cut of GeV, appropriate for LHC, the lepton cutoff is 80 GeV. This can be
exploited to effectively eliminate the background from the like sign
dilepton channel apropriate for Majorana particle searches, as well as the
unlike sign dilepton and the single lepton channels appropriate for the top
quark search. We illustrate this with a detailed analysis of the background
in these channels along with the signals at LHC energy using both parton level
MC and ISAJET programs.Comment: TIFR/TH/93-23 (LATEX, 20 pages, 7 figures available on request
Status Updates Over Unreliable Multiaccess Channels
Applications like environmental sensing, and health and activity sensing, are
supported by networks of devices (nodes) that send periodic packet
transmissions over the wireless channel to a sink node. We look at simple
abstractions that capture the following commonalities of such networks (a) the
nodes send periodically sensed information that is temporal and must be
delivered in a timely manner, (b) they share a multiple access channel and (c)
channels between the nodes and the sink are unreliable (packets may be received
in error) and differ in quality.
We consider scheduled access and slotted ALOHA-like random access. Under
scheduled access, nodes take turns and get feedback on whether a transmitted
packet was received successfully by the sink. During its turn, a node may
transmit more than once to counter channel uncertainty. For slotted ALOHA-like
access, each node attempts transmission in every slot with a certain
probability. For these access mechanisms we derive the age of information
(AoI), which is a timeliness metric, and arrive at conditions that optimize AoI
at the sink. We also analyze the case of symmetric updating, in which updates
from different nodes must have the same AoI. We show that ALOHA-like access,
while simple, leads to AoI that is worse by a factor of about 2e, in comparison
to scheduled access
Nucleophilicity/Electrophilicity Excess in Analyzing Molecular Electronics
Intramolecular electron transfer capability of all metal aromatic and
anti-aromatic aluminum cluster compounds is studied in terms of density
functional theory based global and local reactivity descriptors. This study
will provide important inputs towards the fabrication of the material required
for molecular electronics.Comment: 21 pages, 6 figures, 13 table
Permeability of a one-dimensional potential barrier
Permeability of one dimensional potential barrie
- …