706 research outputs found
Jet Investigations Using the Radial Moment
We define the radial moment, , for jets produced in hadron-hadron
collisions. It can be used as a tool for studying, as a function of the jet
transverse energy and pseudorapidity, radiation within the jet and the quality
of a perturbative description of the jet shape. We also discuss how
non-perturbative corrections to the jet transverse energy affect .Comment: 14 pages, LaTeX, 6 figure
Copy number variants are produced in response to low‐dose ionizing radiation in cultured cells
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106089/1/em21840.pd
Supersymmetric structure of electroweak Sudakov corrections
Electroweak radiative corrections can be evaluated in the Sudakov
approximation, a systematic high energy expansion known to be relevant for the
analysis of future collider experiments in the TeV energy range. In the Minimal
Supersymmetric Standard Model and at next-to-leading order, Sudakov electroweak
corrections satisfy remarkable relations at the one loop level. Explicit
computations in component fields are available for various different
processes relevant for Linear Collider or LHC physics. The Sudakov corrections
turn out to be equal or closely related in several classes of processes
differing by the replacement of certain final or initial states with their
superpartners. This fact suggests that supersymmetry is partially restored at
high-energy. We analyze the supersymmetric structure of such relations by
computing the Sudakov corrections in the framework of superfield perturbation
theory. As a simple application, we derive in full details an extended complete
set of supersymmetric relations among different processes related by
supersymmetry to the fundamental fermion pair production process .Comment: 22 pages, 7 eps figure
Children of prisoners: exploring the impact of families' reappraisal of the role and status of the imprisoned parent on children's coping strategies
Qualitative data from a larger study on the impact of parental imprisonment in four countries found that children of prisoners face fundamentally similar psychological and social challenges. The ways that children cope, however, are influenced by the interpretative frame adopted by the adults around them, and by how issues of parental imprisonment are talked about in their families. This article argues that families have to reappraise their view of the imprisoned parent and then decide on their policy for how to deal with this publicly. Their approach may be based on openness and honesty or may emphasise privacy and secrecy, or a combination of these. Children are likely to be influenced by their parents'/carers' views, although these may cause conflict for them. Where parents/carers retain a positive view of the imprisoned parent, children are likely to benefit; where parents/carers feel issues of shame and stigma acutely, this is likely to be transmitted to their children. This is important for social workers and practitioners involved in supporting prisoners' families and for parenting programmes
Schottky-based band lineups for refractory semiconductors
An overview is presented of band alignments for small-lattice parameter, refractory semiconductors. The band alignments are estimated empirically through the use of available Schottky barrier height data, and are compared to theoretically predicted values. Results for tetrahedrally bonded semiconductors with lattice constant values in the range from C through ZnSe are presented. Based on the estimated band alignments and the recently demonstrated p-type dopability of GaN, we propose three novel heterojunction schemes which seek to address inherent difficulties in doping or electrical contact to wide-gap semiconductors such as ZnO, ZnSe, and ZnS
Three-jet cross sections in hadron-hadron collisions at next-to-leading order
We present a new QCD event generator for hadron collider which can calculate
one-, two- and three-jet cross sections at next-to-leading order accuracy. In
this letter we study the transverse energy spectrum of three-jet hadronic
events using the kT algorithm. We show that the next-to-leading order
correction significantly reduces the renormalization and factorization scale
dependence of the three-jet cross section.Comment: 4 pages, 4 figures, REVTEX
Low power radiometric partial discharge sensor using composite transistor-reset integrator
The measurement of partial discharge provides a means of monitoring insulation health in high-voltage equipment. Traditional partial discharge measurements require separate installation for each item of plant to physically connect sensors with specific items. Wireless measurement methods provide an attractive and scalable alternative. Existing wireless monitoring technologies which use time-difference-of-arrival of a partial discharge signal at multiple, spatially separated, sensors place high demands on power consumption and cost due to a requirement for rapid sampling. A recently proposed partial discharge monitoring system using a wireless sensor network and measuring received signal strength only, has potential cost and scalability advantages. An incoherent wireless sensor incorporating a transistor-reset integrator has been developed that reduces the measurement bandwidth of the PD events and alleviates the need for high-speed sampling. It is based on composite amplifier techniques to reduce the power requirements by a factor of approximately four without compromising precision. The accuracy of the proposed sensor is compared to that obtained using a high-speed digital sampling oscilloscope. Received energies were measured over a 10 m distance in 1 m increments and produced an error within 1 dB beyond 4 m and 3.2 dB at shorter distances, resulting in a measurement accuracy within 1 m
Energy gap in superconducting fullerides: optical and tunneling studies
Tunneling and optical transmission studies have been performed on
superconducting samples of Rb3C60. At temperatures much below the
superconducting transition temperature Tc the energy gap is 2 Delta=5.2 +-
0.2meV, corresponding to 2 Delta/kB Tc = 4.2. The low temperature density of
states, and the temperature dependence of the optical conductivity resembles
the BCS behavior, although there is an enhanced ``normal state" contribution.
The results indicate that this fulleride material is an s-wave superconductor,
but the superconductivity cannot be described in the weak coupling limit.Comment: RevTex file with four .EPS figures. Prints to four pages. Also
available at http://buckminster.physics.sunysb.edu/papers/pubrece.htm
No Far-Infrared-Spectroscopic Gap in Clean and Dirty High-T Superconductors
We report far infrared transmission measurements on single crystal samples
derived from BiSrCaCuO. The impurity scattering rate of
the samples was varied by electron-beam irradiation, 50MeV O ion
irradiation, heat treatment in vacuum, and Y doping. Although substantial
changes in the infrared spectra were produced, in no case was a feature
observed that could be associated with the superconducting energy gap. These
results all but rule out ``clean limit'' explanations for the absence of the
spectroscopic gap in this material, and provide evidence that the
superconductivity in BiSrCaCuO is gapless.Comment: 4 pages and 3 postscript figures attached. REVTEX v3.0. Accepted for
publication in Phys. Rev. Lett. IRDIRT
Single-top production at future ep colliders
The production of top quarks in single mode at future ep colliders is
studied, the attention being mainly focused to the case of the proposed LEPXLHC
collider. We are motivated to reanalyse such a process following the discovery
of the top quark at Fermilab. Thanks to the measurement of its mass one is now
able to establish more accurately the relevance of single top production for
itself and for many other processes to which it may act as a background. In
addition, the recent improvement of our knowledge of the quark and gluon
dynamics inside the proton now allows one to pin down the dependence of single
top production on the partonic structure functions. Both the leptonic and
hadronic decay channels of the top quark are studied and compared to the yield
of the corresponding irreducible background in presence of b-taggingComment: 28 pages, latex, epsfig, 10 postscript figures, complete paper
available at ftp://axpa.hep.phy.cam.ac.uk/moretti/cavendish_9704 and at
http://www.hep.phy.cam.ac.uk/theory/papers
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