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RADIATION DAMAGE TO BSCCO-2223 FROM 50 MEV PROTONS

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

PDII- Additional discussion of the dynamic aperture

Description: This note is in the nature of an addition to the dynamic aperture calculations found in the report on the Proton Driver, FERMILAB-TM-2169. A extensive discussion of the Proton Driver lattice, as well as the nomenclature used to describe it can be found in TM-2169. Basically the proposed lattice is a racetrack design with the two arcs joined by two long straight sections. The straight sections are dispersion free. Tracking studies were undertaken with the objective of computing the dynamic aperture for the lattice and some of the results have been incorporated into TM-2169. This note is a more extensive report of those calculations.
Date: July 23, 2002
Creator: Gelfand, Norman M.
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

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

Slip stacking

Description: We have started beam studies for ''slip stacking''[1] in the Main Injector in order to increase proton intensity on a target for anti-proton production. It has been verified that the system for slip stacking is working with low intensity beam. For a high intensity operation, we are developing a feedback[2][3] and feedforward system.
Date: September 19, 2002
Creator: Steimel, Kiyomi Koba and James
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

Synchro-betatron resonances in the 8 GeV proton driver

Description: The major difference of these two versions is the size (circumference) and the maximum energy. In the first study, the circumference is chosen to be 711.3m, which is 1.5 times the present Booster, with the maximum energy of 16 GeV. In the second version, it is mandated to be the same as Booster together with the same maximum energy of 8 GeV. One of the major impacts of the reduced size of the ring is the inevitable reduction in the total length of available space for injection/collimation/extraction systems and for rf cavities, 14 slots of 7.43m each in the smaller ring compared with 24 slots of 6.15m each in the larger ring. Since each cavity occupies a slot of 2.35m and 22 cavities are desirable, seven or eight slots out of 14 in the smaller ring must be reserved for rf, only six or seven remaining for all other systems. The constraint in space is particularly troublesome for the extraction system since the beam loss at extraction (at the highest beam energy) is the major concern of any high intensity proton machines.
Date: December 2, 2002
Creator: Ohnuma, Shoroku
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

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

COMPARISON BETWEEN THE PREDICTIONS AND MEASUREMENTS FOR THE BEAM GAS INTERACTIONS DURING THE LAST GOLD AND PROTON RUNS IN RHIC.

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
Creator: TRBOJEVIC,D.; HSEUH,H.C.; FISCHER,W.; ZHANG,S.Y. & MACKAY,W.W.
Partner: UNT Libraries Government Documents Department

ACCELERATING AND COLLIDING POLARIZED PROTONS IN RHIC WITH SIBERIAN SNAKES.

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
Creator: ROSER,T.; AHRENS,L.; ALESSI,J.; BAI,M.; BEEBE - WANG,J.; BRENNAN,J.M. et al.
Partner: UNT Libraries Government Documents Department

A P + DEUTERON PROTON POLARIMETER AT 200 MEV.

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
Creator: HUANG,H.; ROSER,T.; ZELENSKI,A.; KURITA,K.; STEPHENSON,E. & TOOLE,R.
Partner: UNT Libraries Government Documents Department

Range Energy Relation for Protons in Nuclear Emulsions

Description: An experimental range-energy relation in Ilford C-2 emulsion has been obtained for proteins up to 39.5 Mev. In the region from 17 to 33 Mev the relation for dry emulsion is fitted by the empirical equation E{sub (MeV)} = 0.251 R{sub ({mu})} 0.581. Variations in water content due to changes in atmospheric humidity make several percent difference in range. The range in Ilford glass is found to be 18 {+-} 4 percent longer than in dry C-2 emulsion.
Date: September 9, 1949
Creator: Bradner, H.; Smith, F.M.; Barkas, W.H. & Bishop, A.S.
Partner: UNT Libraries Government Documents Department

Half-Scale Model Tests on the Three Quarter Wave R.F. System for the 184-inch Frequency Modulated Cyclotron

Description: Performance curves and test results on a half scale model of the radio frequency system designed to accelerate protons in the Berkeley 184-inch cyclotron are presented. This report is a sequel to K. R. Mackenzie's report on the three quarter wave radio frequency system for frequency modulated cyclotrons.
Date: December 30, 1947
Creator: Anderson, Robert L.
Partner: UNT Libraries Government Documents Department

Reliable-linac design for accelerator-driven subcritical reactor systems.

Description: Accelerator reliability corresponding to a very low frequency of beam interrupts is an important new accelerator requirement for accelerator-driven subcritical reactor systems. In this paper we review typical accelerator-reliability requirements and discuss possible methods for meeting these goals with superconducting proton-linac technology.
Date: January 1, 2002
Creator: Wangler, Thomas P.,
Partner: UNT Libraries Government Documents Department