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Preliminary spectrometer results from E-802
No full textThis report presents preliminary spectrometer results from the E-802 experiment at the Tandem-AGS accelerator complex at Brookhaven National Laboratory. The data presented were taken in late April of 1987 using a 14.5 GeV/c per nucleon /sup 28/Si beam from the AGS. Data were obtained for a variety of targets and spectrometer settings, but we present here the analysis of data for one target-angle combination: a Au target wth the spectrometer spanning 14/sup 0/ to 28/sup 0/ in the lab. At this energy the laboratory mid-rapidity angle in N-N collisions is approx. = 21/sup 0/. A higher K/sup +//..pi../sup +/ ratio than K/sup -//..pi../sup -/ ratio is observed. The primary goal for the E-802 experiment is to measure inclusive particle spectra with good particle identification (PID) over a wide range of rapidity and transverse momentum, and to correlate these spectra with observables that characterize the vent topology such as total charged particle multiplicity and neutral transverse energy. The acceptance of the spectrometer is large enough to span roughly one unit of rapidity in a single setting and is adequate for studies of particle-particle correlations. The spectrometer is also sufficiently compact (6.5 m in length) to allow a reasonable fraction of low momentum pions and kaons to traverse the entire particle identification system. Segmentation for the tracking and PID counters was designed to handle particle multiplicities up to 15 through the spectrometer and 20 in front of the magnet
ATLAS Measurements of Isolated Photon Cross-Sections
No full textA measurement of the cross section for the inclusive production of isolated prompt photons in pp collisions at a centre-of-mass energy ~TeV is presented, as well as a measurement of di-photon production. Photon candidates are identified by combining information from the calorimeters and from the inner tracker. Residual background in the selected sample is estimated from data based on the observed distribution of the transverse isolation energy in a narrow cone around the photon candidate. The results are compared to predictions from next-to-leading order perturbative QCD calculations
Resolution of the proton radius puzzle via off-shell form factors
No full textWe show that off-mass-shell effects arising from the internal structure of the proton provide a new proton polarization mechanism in the Lamb shift, proportional to the lepton mass to the fourth power. This effect is capable of resolving the current puzzle regarding the difference in the proton radius extracted from muonic compared with electronic hydrogen experiments. These off-mass-shell effects could be probed in several other experiments. A significant ambiguity appearing in dispersion relation evaluations of the proton polarizability contribution to the Lamb shift is noted. © 2012 American Institute of Physics.Gerald A. Miller, Anthony W. Thomas, Jonathan D. Carroll and Johann Rafelsk
Projectilelike fragments from N14 beams at 15, 25, and 35 MeV/nucleon
No full textMomentum distributions of projectilelike fragments produced in the interaction of 15, 25, and 35 MeV/nucleon N14 beams on targets of C12, Mg24, Al27, Ti48, and Ni58 have been measured. Widths and centroids of the quasielastic component of the distributions have been extracted for fragments ranging from He4 to N13. The widths are compared with published data and several theoretical predictions. The Friedman model correctly predicts the charge and isotope dependence of the widths at the highest beam energy. At 15 MeV/nucleon some deviations from the trend of the published data suggest the possibility of a different reaction mechanism for the projectile-target combinations studied in the present work
Nucleon excitations in 2+1 flavor QCD
No full textA determination of the excited state spectrum of hadrons presents a significant challenge to the first-principles approach of Lattice QCD. Here a brief overview of the correlation-matrix methods developed recently by the CSSM Lattice Collaboration for the isolation of excited states of the nucleon is presented. The utility of the method is shown by exploring the first twelve states of the nucleon in the positive parity channel. Of particular interest is the Roper resonance, the first positive-parity excited-state of the nucleon. A low-lying Roper state is observed in full QCD calculations for the first time, showing significant curvature as the chiral regime is approached. The negative parity results are also explored, where the extracted first negative parity excited state approaches the physical value. © 2012 American Institute of Physics.M. S. Mahbub, W. Kamleh, D. B. Leinweber, P. J. Moran and A. G. William
A 10kc Kerr cell modulator for the production of repetitive giant laser pulse
No full textThe output from a conventional laser is a spontaneous burst of radiation which lasts about one microsecond. If now the reflectivity of one of the two "mirrors " in the system is controllable, it is possible to develop laser system conditions which permit the generation of high peak-power pulses with a pulse width of about 30 nanoseconds. Such a system utilizes the principle of regeneration modulation and has been successfully applied to the production of single high peak-power pulses. A natural step then is to utilize this method to generate a
series of repetitive "giant" pulses.
This report describes the electronics equipment developed to assist in producing such pulses at
a 10 kc pulse repetition frequency. The
approach used represents a first attempt towards an effective means of obtaining controlled high-powered laser pulses.
The author extends appreciation to all the members of the Hughes Aircraft Company laser
Research group who offered their advice and
knowledge.
The final successful days of the experiment were under the guidance of Dr. E. Woodbury .
The author was also directly and ably assisted
during the final stages of the experiment by engineer-physicist Mr. B.E. Dobratz. Also,
gratitude and appreciation is offered to Mr. E.D. Stephans for his special kind of guidance and good humor.Approved for public release; distribution is unlimited.Captain, United States Marine Corpshttp://archive.org/details/akckerrcellmodul109451154
Measurement of Evaporation Residue Cross Sections for the Si + C Reaction at E(Si) = 309,397 and 451 MeV
No full textMeasurement of Evaporation Residue Cross Sections for the Si + C Reaction at E(Si) = 309,397 and 451 MeV
No full textGeneration of Functional CLL-Specific Cord Blood CTL Using CD40-Ligated CLL APC
No full textPMCID: PMC3526610This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
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