48 research outputs found
Gravitation and inertia; a rearrangement of vacuum in gravity
We address the gravitation and inertia in the framework of 'general gauge
principle', which accounts for 'gravitation gauge group' generated by hidden
local internal symmetry implemented on the flat space. We connect this group to
nonlinear realization of the Lie group of 'distortion' of local internal
properties of six-dimensional flat space, which is assumed as a toy model
underlying four-dimensional Minkowski space. The agreement between proposed
gravitational theory and available observational verifications is satisfactory.
We construct relativistic field theory of inertia and derive the relativistic
law of inertia. This theory furnishes justification for introduction of the
Principle of Equivalence. We address the rearrangement of vacuum state in
gravity resulting from these ideas.Comment: 17 pages, no figures, revtex4, Accepted for publication in Astrophys.
Space Sc
Low Q^2 Jet Production at HERA and Virtual Photon Structure
The transition between photoproduction and deep-inelastic scattering is
investigated in jet production at the HERA ep collider, using data collected by
the H1 experiment. Measurements of the differential inclusive jet
cross-sections dsigep/dEt* and dsigmep/deta*, where Et* and eta* are the
transverse energy and the pseudorapidity of the jets in the virtual
photon-proton centre of mass frame, are presented for 0 < Q2 < 49 GeV2 and 0.3
< y < 0.6. The interpretation of the results in terms of the structure of the
virtual photon is discussed. The data are best described by QCD calculations
which include a partonic structure of the virtual photon that evolves with Q2.Comment: 20 pages, 5 Figure
Hadron Production in Diffractive Deep-Inelastic Scattering
Characteristics of hadron production in diffractive deep-inelastic
positron-proton scattering are studied using data collected in 1994 by the H1
experiment at HERA. The following distributions are measured in the
centre-of-mass frame of the photon dissociation system: the hadronic energy
flow, the Feynman-x (x_F) variable for charged particles, the squared
transverse momentum of charged particles (p_T^{*2}), and the mean p_T^{*2} as a
function of x_F. These distributions are compared with results in the gamma^* p
centre-of-mass frame from inclusive deep-inelastic scattering in the
fixed-target experiment EMC, and also with the predictions of several Monte
Carlo calculations. The data are consistent with a picture in which the
partonic structure of the diffractive exchange is dominated at low Q^2 by hard
gluons.Comment: 16 pages, 6 figures, submitted to Phys. Lett.
Energy Flow in the Hadronic Final State of Diffractive and Non-Diffractive Deep-Inelastic Scattering at HERA
An investigation of the hadronic final state in diffractive and
non--diffractive deep--inelastic electron--proton scattering at HERA is
presented, where diffractive data are selected experimentally by demanding a
large gap in pseudo --rapidity around the proton remnant direction. The
transverse energy flow in the hadronic final state is evaluated using a set of
estimators which quantify topological properties. Using available Monte Carlo
QCD calculations, it is demonstrated that the final state in diffractive DIS
exhibits the features expected if the interaction is interpreted as the
scattering of an electron off a current quark with associated effects of
perturbative QCD. A model in which deep--inelastic diffraction is taken to be
the exchange of a pomeron with partonic structure is found to reproduce the
measurements well. Models for deep--inelastic scattering, in which a
sizeable diffractive contribution is present because of non--perturbative
effects in the production of the hadronic final state, reproduce the general
tendencies of the data but in all give a worse description.Comment: 22 pages, latex, 6 Figures appended as uuencoded fil
A Search for Selectrons and Squarks at HERA
Data from electron-proton collisions at a center-of-mass energy of 300 GeV
are used for a search for selectrons and squarks within the framework of the
minimal supersymmetric model. The decays of selectrons and squarks into the
lightest supersymmetric particle lead to final states with an electron and
hadrons accompanied by large missing energy and transverse momentum. No signal
is found and new bounds on the existence of these particles are derived. At 95%
confidence level the excluded region extends to 65 GeV for selectron and squark
masses, and to 40 GeV for the mass of the lightest supersymmetric particle.Comment: 13 pages, latex, 6 Figure
A Measurement of the Proton Structure Function
A measurement of the proton structure function is reported
for momentum transfer squared between 4.5 and 1600 and
for Bjorken between and 0.13 using data collected by the
HERA experiment H1 in 1993. It is observed that increases
significantly with decreasing , confirming our previous measurement made
with one tenth of the data available in this analysis. The dependence is
approximately logarithmic over the full kinematic range covered. The subsample
of deep inelastic events with a large pseudo-rapidity gap in the hadronic
energy flow close to the proton remnant is used to measure the "diffractive"
contribution to .Comment: 32 pages, ps, appended as compressed, uuencoded fil
Nanoscale Sensing Vitrification of 3D Confined Glassy Polymers through Refractory Thermoplasmonics
Advances in plasmonics have been fundamentally rooted in minimizing ohmic losses in metallic nanostructures. However, the losses at resonance can play a positive role; for instance, in optical heating, there are two sides to every story. Under laser illumination, plasmonic nanostructures serve not only as near-field enhancers but heat generators. The emerging field of thermoplasmonics opens up unprecedented possibilities to probe temperature-dependent phase transitions locally. In this paper, we develop a new approach behind plasmon-assisted optical heating for spectroscopically recognizing the glass transition temperature (Tg) of spatially confined poly(methyl methacrylate) (PMMA) polymers deposited on a square-shaped titanium nitride (TiN) pad. A local photoheating is controlled through Raman thermometry of a c-Si (100) substrate that functions as a temperature-sensing Raman reporter. The reliability of temperature measurements is corroborated by using both the anti-Stokes/Stokes ratio and the Raman peak shift. We show that optical heating can be adjusted by extruding a c-Si substrate, for example, the temperature increase is achieved by making c-Si pillars beneath the TiN pads longer. This peculiarity gives the possibility to probe the Tg in a broad temperature range for the diversity of glassy polymers. We believe that the developed method will pave the way for 2D mapping structural glass transitions of heterogeneous glassy polymers, polymeric blends, and eventually, 3D confined polymers