122964093
Search for Tachyon Monopoles in Cosmic Rays
We have searched for a particle which combines the properties of a tachyon with those of a magnetic monopole. The tachyon monopole is assumed to exist in cosmic rays striking the earth and to be influenced by the extensive magnetic fringing field of Fermilab's 15-ft. bubble chamber. By hypothesizing that the tachyon monopole will either emit Cherenkov radiation in air or ionize Lexan plastic we set an upper limit of 5 x 10/sup 12/ cm/sup -2/ sec/sup -1/ on their flux.
123674916
HEAVY IONS AND HIGHER PROTON CURRENTS PROPOSED FOR THE PRINCETON-- PENNSYLVANIA ACCELERATOR.
118179130
Search for Monopoles Above the 15-Foot Bubble Chamber
Magnetic monopoles having energies less than about 40 TeV will be slowed to their terminal velocity by the earth's atmosphere. They may then be gathered by the fringing magnetic field of the 15-foot bubble chamber. We propose placing detectors of Lexan and nuclear emulsion at convenient locations above and below the bubble chamber. Such a systom would be sensitive to monopole masses between 10 GeV and 100 TeV and to monopole charges between {approx}0.7 and 10 hc/2e. The experiment would require the construction of a special light roof and would run for 5 weeks during a time when the bubble chamber is filled with air and not in use for other experiments. This study would lower the existing limit on in-flight detection of monopoles (at the earth's surface) by a factor of 20.
123909158
DESIGN AND OPERATION OF THE PRINCETON-PENNSYLVANIA PROTON SYNCHROTRON
The 16 sector magnet is weak focusing with n = 0.6 over a useful radial region of 16.5 cm and 6.1 cm vertically. A d-c biased, sine wave excitation at 19 cps is employed, the energy storage being in a resonant capacitor-inductor system. Injection at 3 Mev is provided by an electrostatic generator. Acceleration is achieved by a combination of drift tubes and resonant cavities which must provide 120 kv per turn, and must be precisely tuned over a 12: 1 range in frequency. To date, 2 x 10/sup 10/ protons per pulse have been injected, of which about 10% are captured by the r-f. A method for extracting the proton beam, which is similar to Piccionis' system, but freer of aberrations, is now under design. (auth)
120485938
The Acceleration of Heavy Ions to Very High Energies and Their Scientific Significance
118661436
The Princeton-Pennsylvania 3 GeV Proton Accelerator as a Nuclear Tool
I would like to describe the Princeton-Pennsylvania Accelerator as a tool for nuclear research. Some people tend to think of the PPA as being too high in energy for nuclear research and, therefore, regard it as only an elementary particle research tool. While much of our work has, in fact, been related to the study of mesons, especially K-mesons, and to the study of the invariance principles, such as C, P, T, about 15% of the research has been either purely nuclear, or with strong nuclear overtones. As examples of the purely nuclear, I mention spallation reactions at 3 BeV and the study of the resulting neutron deficient nuclei. On the other side of the valley are the baryon stable, neutron rich, light fragments, 19N and 21O, which have been discovered in confirmation of Garvey’s mass formula. Negative pion scattering by twelve different complex nuclei from Be to Au over the energy range 600-1600 MeV has been used to determine optical model potentials. Neutron total cross sections over the momentum range 500-2800 MeV/c are now being studied for a wide variety of target nuclei, including the Physical Review! An especially beautiful experiment, begun as a missing mass search in the reaction p+d → He3+X° not only studied things of interest to elementary particle physics, the so-called ABC region, but simultaneously, and inadvertently, provided a hadronic probe, the proton, at correlation distances far smaller than, ever achieved before.
118494817
Mass Estimation without using MET in early LHC data
Many techniques exist to reconstruct New Physics masses from LHC data, though these tend to either require high luminosity O(100) fb^-1, or an accurate measurement of missing transverse energy (MET) which may not be available in the early running of the LHC. Since in popular models such as SUSY a fairly sharp, triangular dilepton invariant mass spectrum can emerge already at low luminosity O(1) fb^-1, a Decay Kinematics (DK) technique can be used on events near the dilepton mass endpoint to estimate squark, slepton, and neutralino masses without relying on MET. With the first 2 fb^-1 of 7 TeV LHC data SPS1a masses can thus be found to 20% or better accuracy, at least several times better than what has been taken to be achievable.
14135931
Three body kinematic endpoints in SUSY models with non-universal Higgs masses
We derive and present expressions for the kinematic endpoints that arise in the invariant mass distributions of visible decay products of cascade decays featuring a two body decay followed by a three body decay. This is an extension of a current technique that addresses chains of successive two body decays. We then apply these to a supergravity model with Non-Universal Higgs Masses (NUHM), having simulated a data set using the ATLFAST detector simulation. We find that, should such a model be chosen by nature, the endpoints will be visible in ATLAS data, and we discuss the problems associated with mass reconstruction in models with a similar phenomenology.
44121878
Numerical Model for Conduction-Cooled Current Lead Heat Loads
Current leads are utilized to deliver electrical power from a room temperature junction mounted on the vacuum vessel to a superconducting magnet located within the vacuum space of a cryostat. There are many types of current leads used at laboratories throughout the world; however, conduction-cooled current leads are often chosen for their simplicity and reliability. Conduction-cooled leads have the advantage of using common materials, have no superconducting/normal state transition, and have no boil-off vapor to collect. This paper presents a numerical model for conduction-cooled current lead heat loads. This model takes into account varying material and fluid thermal properties, varying thicknesses along the length of the lead, heat transfer in the circumferential and longitudinal directions, electrical power dissipation, and the effect of thermal intercepts. The model is validated by comparing the numerical model results to ideal cases where analytical equations are valid. In addition, the XFEL (X-Ray Free Electron Laser) prototype current leads are modeled and compared to the experimental results from testing at DESY's XFEL Magnet Test Stand (XMTS) and Cryomodule Test Bench (CMTB).
117428092
Constraining the MSSM with Dark Matter indirect detection data
Recently, a claim of possible evidence for Dark Matter in data from the Fermi LAT experiment was made by Goodenough and Hooper [8]. We test the Dark Matter properties consistent with their claim in terms of the MSSM by a 24-dimensional parameter scan using nested sampling, excluding all but a very small region of the MSSM. Although this claim is very preliminary, and not made by the Fermi LAT experiment, our scan shows a possible approach for the analysis of future firm evidence from an indirect detection experiment, and its potential for heavily constraining models.
46688174
Diffusion of Gases in Air and Its Affect on Oxygen Deficiency Hazard Abatement
Density differences between air and released gases of cryogenic systems have been used to either require special oxygen deficiency hazard (ODH) control measures, or as a means of abatement. For example, it is not uncommon to assume that helium spills will quickly collect at the ceiling of a building or enclosure and will efficiently exit at the nearest vertical penetration or vent. Oxygen concentration reduction was found to be detectable during a localized helium spill throughout the entire 6.3 km Tevatron tunnel. This prompted us to perform diffusion tests in air with common gases used at Fermilab. The tests showed that gases, more readily than expected, diffused through an air column in the direction opposing buoyancy. Test results for helium and sulfur hexafluoride are presented. A system of tests were performed to better understand how easily released gases would fully mix with air and whether they remained fully mixed. The test results have been applied to a new system at Fermilab for ODH abatement.