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Excitation Functions for Reactions of Bev Protons on Indium (Master's Thesis)

Description: Abstract: "Indium was bombarded with protons in the energy range 2 to 6 Bev. Cross sections are reported for the (p,px+), (p,pn), and (p,p') reactions, as well as those for the formation of Be-7 and several neutron deficient isotopes of cadmium and indium. It was found that the (p,pn) yield increases slowly in the energy range 2 to 6 Bev, while the (p,px+) and (p,p') yields are approximately constant. The variation of the (p,pn) and (p,px+) yields with target thickness is discussed. The yields of several isomeric levels are correlated with their nuclear spin."
Date: January 1957
Creator: Nethaway, David Robert
Partner: UNT Libraries Government Documents Department

Experiments on Polarization in Scatterig Deuterons from Complex Nuclei and in Proton-Proton Scattering (Thesis)

Description: Abstract: "The elastic double scattering of deuterons by complex nuclei has been investigated experimentally. Measurements were made on carbon, aluminum, and copper at around 157 Mev; on lithium, beryllium, and carbon at around 125 Mev; and on carbon and aluminum at 94 Mev. The expected tensor components of the deuteron polarization have not been observed. Measurements have been made of the differential cross section and vector-type polarization as a function of angle for the scattering of deuterons from the above elements, at the above energies. The observed polarizations were larger than would be expected on the basis of the individual nucleon-nucleus interactions. In a second experiment we measured the 169-Mev proton-proton polarization at 10, 15, 22.5, 30, and 35 in the laboratory system. The results indicate that partial waves up to and including L = 3 are important at this energy."
Date: May 11, 1956
Creator: Baldwin, John A., Jr.
Partner: UNT Libraries Government Documents Department

A High-Current Radio-Frequency Ion Accellerator

Description: Abstract: "A radio-frequency ion accelerator is described which is capable of continuous currents of protons of 250 ma at an energy of 500 kev. The beam is less than 3 in. in diameter and has a divergence of less than 2 degree half angle. Operation of the machine accelerating deuterons to an energy of 1000 kev is also described."
Date: February 1957
Creator: Lamb, William A. S.; Hester, Ross E. & Kippenhan, Dean O.
Partner: UNT Libraries Government Documents Department


Description: The use of HTS materials in high radiation environments requires that the superconducting properties remain constant up to a radiation high dose. BSCCO-2223 samples from two manufacturers were irradiated with 50 MeV protons at fluences of up to 5 x 10{sup 17} protons/cm{sup 2}. The samples lost approximately 75% of their pre-irradiation I{sub c}. This compares with Nb{sub 3}Sn, which loses about 50% at the same displacements per atom.
Date: November 1, 2007
Creator: Zeller, A.F.; Ronningen, R.M.; Godeke, Arno; Heibronn, L.H; McMahan-Norris, P. & Gupta, R.
Partner: UNT Libraries Government Documents Department

Standard Practice for Dosimetry of Proton Beams for use in Radiation Effects Testing of Electronics

Description: Representatives of facilities that routinely deliver protons for radiation effect testing are collaborating to establish a set of standard best practices for proton dosimetry. These best practices will be submitted to the ASTM International for adoption.
Date: July 25, 2008
Creator: McMahan, Margaret A.; Blackmore, Ewart; Cascio, Ethan W.; Castaneda, Carlos; von Przewoski, Barbara & Eisen, Harvey
Partner: UNT Libraries Government Documents Department

Slip stacking experiments at Fermilab main injector

Description: In order to achieve an increase in proton intensity, Fermilab Main Injector will use a stacking process called ''slip stacking''. The intensity will be doubled by injecting one train of bunches at a slightly lower energy, another at a slightly higher energy, then bringing them together for the final capture. Beam studies have started for this process and we have already verified that, at least for a low beam intensity, the stacking procedure works as expected. For high intensity operation, development work of the feedback and feedforward systems is under way.
Date: June 2, 2003
Creator: al., Kiyomi Koba et
Partner: UNT Libraries Government Documents Department

Magnets for high intensity proton synchrotrons

Description: Recently, there has been considerable interest at Fermilab for the Proton Driver, a future high intensity proton machine. Various scenarios are under consideration, including a superconducting linac. Each scenario present some special challenges. We describe here the magnets proposed in a recent study, the Proton Driver Study II, which assumes a conventional warm synchrotron, roughly of the size of the existing FNAL booster, but capable of delivering 380 kW at 8 GeV.
Date: September 19, 2002
Creator: Jean-Francois Ostiguy, Vladimir Kashikhine and Alexander Makarov
Partner: UNT Libraries Government Documents Department


Description: The last gold-gold and polarized proton-proton collision runs were performed at energies of 100 GeV/nucleon. The beam gas interactions in RHIC are very important for the beam lifetime in RHIC. In this report the lifetime predicted by pressure data differences between the beams ON and beams OFF, at the energies of 100 GeV/nucleon. are compared to the predictions for the beam gas interaction and beam lifetimes.
Date: June 2, 2002
Partner: UNT Libraries Government Documents Department

Proton irradiation effects on 2Gb flash memory

Description: The authors report total ionizing dose and single event effects on 2Gb Samsung flash memory devices after exposure to 200 MeV protons to various doses up to 83 krad(Si). They characterize observed failures and single event upsets on 22 devices from two different lots. Devices from both lots are robust to greater than 20 krad(Si) although they see evidence for lot-to-lot variation where only one lot appears robust up to about 50 krad(Si). Single event upsets are observed at a relatively low rate and are consistent with single isolated bit flips within registers that transfer bits to and from the flash memory cells.
Date: August 18, 2004
Creator: Wester, William; Nelson, Charles & Marriner, John
Partner: UNT Libraries Government Documents Department


Description: There has been concern about the analyzing power of the p-Carbon polarimeter at the end of 200 MeV LINAC of BNL. A new polarimeter based on proton-deuteron scattering was installed and we have repeated the calibration of proton-Carbon scattering at 12 degrees and 200 MeV against proton-deuteron scattering. The result is consistent with the value of A=0.62 now used to measure the beam polarization at the end of the LINAC.
Date: June 2, 2002
Partner: UNT Libraries Government Documents Department

Energetic Proton Generation in Ultra-Intense Laser-Solid Interactions

Description: An explanation for the energetic ions observed in the PetaWatt experiments is presented. In solid target experiments with focused intensities exceeding 10{sup 20} W/cm{sup 2}, high-energy electron generation, hard bremsstrahlung, and energetic protons have been observed on the backside of the target. In this report, we attempt to explain the physical process present that will explain the presence of these energetic protons, as well as explain the number, energy, and angular spread of the protons observed in experiment. In particular, we hypothesize that hot electrons produced on the front of the target are sent through to the back off the target, where they ionize the hydrogen layer there. These ions are then accelerated by the hot electron cloud, to tens of MeV energies in distances of order tens of microns, whereupon they end up being detected in the radiographic and spectrographic detectors.
Date: March 1, 2000
Creator: Wilks, S.C.; Langdon, A.B.; Cowan, T.E.; Roth, M.; Singh, M.; Hatchett, S. et al.
Partner: UNT Libraries Government Documents Department

Tevatron stripline turn by turn data and the head-tail instability

Description: Vic Scarpine recently collected turn by turn data from the vertical wideband stripline in the Tevatron during proton injection for store 1841. The data file name is ''PHT004.txt''. The single bunch intensity was roughly 200e9. The chromaticity was set to ''+6'' horizontal and ''-2'' vertical to induce instability. The data shown represents an extreme condition that shortly preceded losses leading to an abort. A Yokogawa DL 7200 oscilloscope was used to measure A-B and A+B simultaneously from the 1 meter long stripline. The scope has an analogue bandwidth of 500MHz with a 2 GHz sample rate. On each of the 2048 turns taken, 200 samples were saved. Vic Scarpine assembled some movie files from the same data that revealed intriguing variations in the A-B signals. The Excel data file contains 2048 turns of A+B followed by 2048 turns of A-B. The 200 samples taken on each turn is placed on one line in the file. Beam was injected at line 14 for A+B and line 2062 for A-B. Eight consecutive turns of data are examined starting at 1490 turns after injection (lines 1504-11 for A+B and 3552-9 for A-B).
Date: December 9, 2002
Creator: Crisp, James L
Partner: UNT Libraries Government Documents Department

Beam collimation and shielding in the Fermilab proton driver

Description: A high beam power in the proposed Fermilab Proton Drivers--1.2 MW in 16-GeV PD-I and 0.48 MW in 8-GeV PD-II--implies serious constraints on beam losses in these machines. Only with a very efficient beam collimation system can one reduce uncontrolled beam losses in the machine to an allowable level. The entire complex must be well shielded to allow acceptable hands-on maintenance conditions in the tunnel and a non-controlled access to the outside shielding at normal operation and accidental beam loss. Collimation and shielding performances are calculated and compared for both Proton Drivers.
Date: June 28, 2002
Creator: Mokhov, Alexandr I. Drozhdin and Nikolai V.
Partner: UNT Libraries Government Documents Department

Beam losses at injection energy and during acceleration in the Tevatron

Description: Protons and anti-protons circulate on helical orbits in the Tevatron. At injection energy (150 GeV) the lifetimes of both species are significantly lower on the helical orbits compared to lifetimes on the central orbit but for different reasons. There are also significant beam losses in both beams when they are accelerated to top energy (980 GeV) again for different reasons. They report on experimental studies to determine the reasons and on methods of improving the lifetimes and losses for both beams.
Date: June 2, 2003
Creator: al., Tanaji Sen et
Partner: UNT Libraries Government Documents Department


Description: We successfully injected polarized protons in both RHIC rings and maintained polarization during acceleration up to 100 GeV per ring using two Siberian snakes in each ring. Each snake consists of four helical superconducting dipoles which rotate the polarization by 180{sup o} about a horizontal axis. This is the first time that polarized protons have been accelerated to 100 GeV. We report on our experiences during commissioning and operation of collider with polarized protons.
Date: June 2, 2002
Partner: UNT Libraries Government Documents Department