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Sample records for texas a and m k500 cyclotron

  1. Progress in research, April 1, 1991--March 31, 1992, Texas A and M University Cyclotron Institute

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1992-06-01

    Reports on research activities, facility operation, and facility development of the Texas A and M Cyclotron Institute for the period 1 April 1991--31 March 1992 are presented in this document. During the report period, the ECR-K500 Cyclotron Combination operated 4,377 hours. Of this time, 832 hours was used for beam development, 942 hours was used for tuning and optics, and the beam was available for experiments 2,603 hours. This time was used in a variety of studies including elastic and inelastic scattering, projectile break-up, the production and decay of giant resonances, fusion and fission dynamics, intermediate mass fragment emission, e{sup +}e{sup {minus}} production and molecular dissociation. In addition, studies of surfaces and metastable states in highly charged ions were carried out using the ECR source. Completion of two 19-element BaF{sub 2} arrays, of the focal plane detector for the proton spectrometer and installation of the HiLi multidetector have provided significant new experimental capabilities which have been further enhanced by major additions to the computer network. Progress on the Mass Achromat Recoil Spectrometer (MARS) is such that first operation of that device should occur this summer. Funding for installation of the MDM spectrometer was obtained at the beginning of this year. As this report is being completed, the Enge Split Pole Spectrometer is being disassembled and removed to make room for the MDM spectrometer. The split-pole will be shipped to CEBAF for use in experiments there. Installation of the MDM should be completed within the next year. Also expected in the next year is a 92 element plastic-CsI ball.

  2. Progress in research, April 1, 1992--March 31, 1993, Texas A and M University Cyclotron Institute

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-07-01

    This Institute annual report for the period 1 April 1992--31 March 1993 covers a period which has seen the initial runs of three new spectrometers which constitute a major portion of the new detection capabilities developed for this facility. These devices are the Proton Spectrometer (PSP), the Mass Achromat Recoil Mass Spectrometer (MARS), and the Multipole dipole Multipole (MDM) Particle Spectrometer. These devices are now available to pursue the studies of Gamow Teller states, reactions of astrophysical interest, and giant resonance studies for which they were constructed, as well as for other experiments. A beam analysis system which will deliver high resolution beams to the MDM spectrometer is currently under construction. With the completion of these spectrometer projects, the facility emphasis is now focused on the development of the full capabilities of the K500 cyclotron and on the research program. During the report period, the ECR-K500 cyclotron combination operated 5,849 hours. Theoretical work reported in this document ranges from nuclear structure calculations using the IBM-2 model to calculations of kaon production and the in-medium properties of the rho and phi mesons, the latter as a probe of the QCD phase transition. Nuclear dynamics and exotic shapes and fragmentation modes of hot nuclei are also addressed. In atomic physics, new measurements of x-ray emission from highly ionized ions, of molecular dissociation and of surface interactions are reported.

  3. Preliminary production of 211At at the Texas A&M University Cyclotron Institute.

    Science.gov (United States)

    Martin, Thomas Michael; Bhakta, Vihar; Al-Harbi, Abeer; Hackemack, Michael; Tabacaru, Gabriel; Tribble, Robert; Shankar, Sriram; Akabani, Gamal

    2014-07-01

    A feasibility study for the production of the alpha particle-emitting radionuclide At was performed at the Texas A&M University Cyclotron Institute as part of the Interdisciplinary Radioisotope Production and Radiochemistry Program. The mission of this program centers upon the production of radionuclides for use in diagnostic and therapeutic nuclear medicine with the primary focus on development of novel therapeutic strategies. As a first step in establishing this program, two goals were outlined: (i) verify production of At and compare results to published data, and (ii) evaluate shielding and radiological safety issues for large-scale implementation using an external target. The radionuclide At was produced via the Bi (α, 2n) At reaction using the K500 cyclotron. Two experiments were conducted, using beam energies of 27.8 MeV and 25.3 MeV, respectively. The resulting yields for At were found to be 36.0 MBq μA h and 12.4 MBq μA h, respectively, which fall within the range of published yield data. Strategies for increasing absolute yield and production efficiency were also evaluated, which focused chiefly on using a new target designed for use with the K150 cyclotron, which will enable the use of a higher beam current. Finally, neutron and gamma dose rates during production were evaluated by using the Monte Carlo code MCNPX. It was determined that a simple structure consisting of 4-in thick borated polyethylene will reduce the neutron dose rate within the cyclotron production vault by approximately a factor of 2, thereby decreasing activation of equipment.

  4. Cryogenic system for VECC K500 superconducting cyclotron

    CERN Document Server

    Pal, G; Bhattacharyya, T K; Bhandari, R K

    2009-01-01

    VEC Centre, Kolkata in India is at an advanced stage of commissioning a K500 superconducting cyclotron. The superconducting coil of the magnet for cyclotron is cooled by liquid helium. Three liquid helium cooled cryopanels, placed inside the Dees of the radiofrequency system, maintain the vacuum in the acceleration region of the superconducting cyclotron. The cryogenic system for magnet for cyclotron has been tested by cooling the coil and energizing the magnet. The cryogenic system for cryopanels has also been tested. Heater and temperature sensor were placed on the liquid helium cold head for cryopanel. The temperature of the cold head was observed to be below 20 K upto a heat load of 11.7 watt.

  5. Progress in research April 1, 1993--March 31, 1994, Texas A and M University Cyclotron Institute

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-07-01

    The period 1 April 1993--31 March 1994 has seen a number of significant developments of the research program as will be noted by the large increase in individual projects reviewed in this annual report. Among the highlights of the K500 experimental program in Sections 1, 2, and 4 are the investigations of excitation energy deposition and of fission dynamics employing both GDR and particle emission probes, measurements of isospin equilibration, studies of (d, {sup 2}He) reactions with the proton spectrometer and of the {beta} decay of {sup 57}Cu with MARS, and the precise studies of ionic charge state distributions using x-ray measurements. Progress in theoretical studies of the nuclear spectral function and the decay of many body systems, on the properties of mesons in hot hadronic matter and on the determination of astrophysical S-factors from experimental studies of very peripheral reactions are presented in Section 3. The status of the LAMPF based MEGA experiment and of the CERN based NA66 experiment, both of which involve institute scientists, is also briefly presented in this report. The shift to a seven day a week operation coupled with installation of cryopanels and more careful temperature control of the cooling water system have resulted in significant improvements in the operational efficiency and beam capabilities. Operating statistics are presented in Section 5.

  6. Accelerated Learning: Undergraduate Research Experiences at the Texas A&M Cyclotron Institute

    Science.gov (United States)

    Yennello, S. J.

    The Texas A&M Cyclotron Institute (TAMU CI) has had an NSF funded Research Experiences for Undergraduates program since 2004. Each summer about a dozen students from across the country join us for the 10-week program. They are each imbedded in one of the research groups of the TAMU CI and given their own research project. While the main focus of their effort is their individual research project, we also have other activities to broaden their experience. For instance, one of those activities has been involvement in a dedicated group experiment. Because not every experimental group will run during those 10 weeks and the fact that some of the students are in theory research groups, a group research experience allows everyone to actually be involved in an experiment using the accelerator. In stark contrast to the REU students' very focused experience during the summer, Texas A&M undergraduates can be involved in research projects at the Cyclotron throughout the year, often for multiple years. This extended exposure enables Texas A&M students to have a learning experience that cannot be duplicated without a local accelerator. The motivation for the REU program was to share this accelerator experience with students who do not have that opportunity at their home institution.

  7. Radioactive beams at Texas A and M University

    CERN Document Server

    Tribble, R E; Gagliardi, C A; Hardy, J C; Mukhamedzhanov, A; Tang, X; Trache, L; Yennello, S J

    2002-01-01

    The combination of the K500 superconducting cyclotron and the recoil spectrometer MARS have been used to generate secondary radioactive ion beams ranging from sup 7 Be at 12 MeV/u to sup 6 sup 2 Ga at 37 MeV/u. Secondary beams are produced via transfer reactions in inverse kinematics using stable beams from the cyclotron on gas targets. The radioactive beams have been used for reaction measurements and beta-decay studies.

  8. The Texas A&M Radioisotope Production and Radiochemistry Program

    Energy Technology Data Exchange (ETDEWEB)

    Akabani, Gamal [Texas A & M Univ., College Station, TX (United States). Dept. of Nuclear Engineering. Dept. of Veterinary Integrative Biosciences

    2016-10-28

    The main motivation of the project at Texas A&M University was to carry out the production of critically needed radioisotopes used in medicine for diagnostics and therapy, and to establish an academic program in radionuclide production and separation methods. After a lengthy battle with the Texas A&M University Radiation Safety Office, the Texas Department of State Health Services granted us a license for the production of radionuclides in July 2015, allowing us to work in earnest in our project objectives. Experiments began immediately after licensing, and we started the assembly and testing of our target systems. There were four analytical/theoretical projects and two experimental target systems. These were for At-211 production and for Zn-62/Cu-62 production. The theoretical projects were related to the production of Mo-99/Tc-99m using a) a subcritical aqueous target system and b) production of Tc-99m from accelerator-generated Mo-99 utilizing a photon-neutron interaction with enriched Mo-100 targets. The two experimental projects were the development of targetry systems and production of At-211 and Zn-62/Cu-62 generator. The targetry system for At-211 has been tested and production of At-211 is chronic depending of availability of beam time at the cyclotron. The installation and testing of the targetry system for the production of Zn-62/Cu-62 has not been finalized. A description of the systems is described. The academic program in radionuclide production and separation methods was initiated in the fall of 2011 and, due to the lack of a radiochemistry laboratory, it was suspended. We expect to re-start the academic program at the Texas A&M Institute for Preclinical Studies under the Molecular Imaging Program.

  9. The Texas A&M Radioisotope Production and Radiochemistry Program

    Energy Technology Data Exchange (ETDEWEB)

    Akabani, Gamal [Texas A & M Univ., College Station, TX (United States)

    2016-08-31

    The main motivation of the project at Texas A&M University was to carry out the production of critically needed radioisotopes used in medicine for diagnostic and therapy, and to establish an academic program in radionuclide production and separation methods. After a lengthy battle with the Texas A&M University Radiation Safety Office, the Texas Department of State Health Services granted us a license for the production of radionuclides in July 2015, allowing us to work in earnest in our project objectives. Experiments began immediately after licensing, and we started the assembly and testing of our target systems. There were four analytical/theoretical projects and two experimental target systems. These were for At-211 production and for Zn- 62/Cu-62 production. The theoretical projects were related to the production of Mo-99/Tc-99m using (a) a subcritical aqueous target system and (b) production of Tc-99m from accelerator-generated Mo-99 utilizing a photon-neutron interaction with enriched Mo-100 targets. The two experimental projects were the development of targetry systems and production of At-211 and Zn-62/Cu-62 generator. The targetry system for At-211 has been tested and production of At-211 is chronic depending of availability of beam time at the cyclotron. The installation and testing of the targetry system for the production of Zn-62/Cu-62 has not been finalized. A description of the systems is described. The academic program in radionuclide production and separation methods was initiated in the fall of 2011; due to the lack of a radiochemistry laboratory, it was suspended. We expect to re-start the academic program at the Texas A&M Institute for Preclinical Studies under the Molecular Imaging Program.

  10. Texas Affordable Baccalaureate Program: A Collaboration between the Texas Higher Education Coordinating Board, South Texas College, and Texas A&M University-Commerce. CBE Case Study

    Science.gov (United States)

    Klein-Collins, Rebecca; Glancey, Kathleen

    2015-01-01

    This case study is part of a series on newer competency-based degree programs that have been emerging in recent years. In January 2014, the Texas Higher Education Coordinating Board (THECB), South Texas College (STC), and Texas A&M University-Commerce (A&M Commerce) launched the Texas Affordable Baccalaureate Program, the state's first…

  11. Public Outreach of the South Texas Health Physic Society and Texas A&M University Nuclear Engineering Department

    Energy Technology Data Exchange (ETDEWEB)

    Berry, R. O.

    2003-02-24

    In a cooperative effort of the members of the South Texas Chapter of the Heath Physics Society (STC-HPS) and the Texas A&M University Nuclear Engineering Department, great efforts have been made to reach out and provide educational opportunities to members of the general public, school age children, and specifically teachers. These efforts have taken the form of Science Teacher Workshops (STW), visits to schools all over the state of Texas, public forums, and many other educational arenas. A major motivational factor for these most recent efforts can be directly tied to the attempt of the State of Texas to site a low-level radioactive waste facility near Sierra Blanca in West Texas. When the State of Texas first proposed to site a low level radioactive waste site after the Low-Level Radioactive Waste Policy Act of 1980 was passed, many years of political struggle ensued. Finally, a site at Sierra Blanca in far West Texas was selected for study and characterization for a disposal site for waste generated in the Texas Compact states of Maine, Vermont and Texas. During this process, the outreach to and education of the local public became a paramount issue.

  12. High energy physics program at Texas A and M University

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    The Texas A M experimental high energy physics program continued to reach significant milestones in each of its research initiatives during the course of the past year. We are participating in two major operating experiments, CDF and MACRO. In CDF, the Texas A M group has spearheaded the test beam program to recalibrate the Forward Hadron Calorimeter for the upcoming CDF data run, as well as contributing to the ongoing analysis work on jets and b-quarks. In MACRO, we have assisted in the development of the final version of the wave form digitizing system being implemented for the entire scintillator system. The construction of the first six supermodules of the detector has been completed and all six are currently taking data with streamer chambers while four have the completed scintillator counter system up and running. We have built and tested prototypes of a liquid-scintillator fiber calorimeter system, in which internally reflecting channels are imbedded in a lead matrix and filled with liquid scintillator. This approach combines the performance features of fiber calorimetry and the radiation hardness of liquid scintillator, and is being developed for forward calorimetry at the SSC. The microstrip chamber is a new technology for precision track chambers that offers the performance required for future hadron colliders. The theoretical high energy physics program has continued to develop during the past funding cycle. We have continued the study of their very successful string-derived model that unifies all known interactions; flipped SU(5), which is the leading candidate for a TOE. Work has continued on some generalizations of the symmetries of string theory, known as W algebras. These are expected to have applications in two-dimensional conformal field theory, two-dimensional extensions of gravity and topological gravity and W-string theory.

  13. A new approach for manufacturing and processing targets to produce 99mTc with cyclotrons

    Science.gov (United States)

    Matei, L.; McRae, G.; Galea, R.; Niculae, D.; Craciun, L.; Leonte, R.; Surette, G.; Langille, S.; Louis, C. St.; Gelbart, W.; Abeysekera, B.; Johnson, R. R.

    2017-06-01

    The most important radioisotope for nuclear medicine is 99mTc. After the supply crisis of 99Mo starting in 2008, the availability of 99mTc became a worldwide concern. Alternative methods for producing the medical imaging isotope 99mTc are actively being developed around the world. The reaction 100Mo(p, 2n)99mTc provides a direct route that can be incorporated into routine production in nuclear medicine centers that possess medical cyclotrons for production of other isotopes, such as those used for Positron Emission Tomography. This paper describes a new approach for manufacturing targets for the (p, 2n) nuclear reaction on 100Mo and the foundation for the subsequent commercial separation and purification of the 99mTc produced. Two designs of targets are presented. The targets used to produce 99mTc are subject to a number of operational constraints.They must withstand the temperatures generated by the irradiation, accommodate temperature gradients from cooling system of the target, must be resilient and must be easily post-processed to separate the 99mTc. After irradiation, the separation of Tc from Mo was carried out using an innovative two-step approach. The process described in this paper can be automated with modules that easily fit in standard production hot cells found in nuclear medicine facilities.

  14. X-ray emission in heavy-ion collisions. Progress report, April 1, 1980-February 28, 1981. [Cyclotron Inst. , Texas A and M Univ. , College Station, 4/1/80-2/28/81

    Energy Technology Data Exchange (ETDEWEB)

    Watson, R.L.

    1981-03-01

    During the past year, work on x-ray emission in heavy-ion collisions has concentrated on the following topics: environmental influences on the K..cap alpha.. x-ray spectra of 65-MeV sulfur ions traveling in solids; multiplet structure of few-electron sulfur ions; multiplet structure of Mg K..cap alpha.. x-ray satellites; polarization of 1s2p..-->..1s/sup 2/ transitions in He-like sulfur ions; and interatomic electron transfer in ionic fluorine compounds following 1s2p vacancy production. Among the most significant accomplishments of the program was a study of the dependence of dynamic screening energy shifts on electron density. It was found that the shifts measured for the 2/sup 1/P..-->..1/sup 1/S and 2/sup 2/P..-->..1/sup 2/S x-ray transitions of He- and H-like sulfur ions (respectively) were in remarkably good agreement with theoretical expectations. Another interesting discovery evolved from measurements of fluorine K..cap alpha.. x-ray spectra for the alkali metal and alkaline earth fluorides using 5.5-MeV He/sup +/ ions. The systematics of these spectra provide the first evidence for direct electron transfer between inner levels of neighboring atoms in a solid. 10 figures, 3 tables. (RWR)

  15. Clinical Trial with Sodium 99mTc-Pertechnetate Produced by a Medium-Energy Cyclotron: Biodistribution and Safety Assessment in Patients with Abnormal Thyroid Function.

    Science.gov (United States)

    Selivanova, Svetlana V; Lavallée, Éric; Senta, Helena; Caouette, Lyne; McEwan, Alexander J B; Guérin, Brigitte; Lecomte, Roger; Turcotte, Éric

    2017-05-01

    A single-site prospective open-label clinical study with cyclotron-produced sodium 99mTc-pertechnetate (99mTc-NaTcO4) was performed in patients with indications for a thyroid scan to demonstrate the clinical safety and diagnostic efficacy of the drug and to confirm its equivalence with conventional 99mTc-NaTcO4 eluted from a generator. Methods:99mTc-NaTcO4 was produced from enriched 100Mo (99.815%) with a cyclotron (24 MeV; 2 h of irradiation) or supplied by a commercial manufacturer (bulk vial eluted from a generator). Eleven patients received 325 ± 29 (mean ± SD) MBq of the cyclotron-produced 99mTc-NaTcO4, whereas the age- and sex-matched controls received a comparable amount of the generator-derived tracer. Whole-body and thyroid planar images were obtained for each participant. In addition to the standard-energy window (140.5 keV ± 7.5%), data were acquired in lower-energy (117 keV ± 10%) and higher-energy (170 keV ± 10%) windows. Vital signs and hematologic and biochemical parameters were monitored before and after tracer administration. Results: Cyclotron-produced 99mTc-NaTcO4 showed organ and whole-body distributions identical to those of conventional 99mTc-NaTcO4 and was well tolerated. All images led to a clear final diagnosis. The fact that the number of counts in the higher-energy window was significantly higher for cyclotron-produced 99mTc-NaTcO4 did not influence image quality in the standard-energy window. Image definition in the standard-energy window with cyclotron-produced 99mTc was equivalent to that with generator-eluted 99mTc and had no particular features allowing discrimination between the 99mTc production methods. Conclusion: The systemic distribution, clinical safety, and imaging efficacy of cyclotron-produced 99mTc-NaTcO4 in humans provide supporting evidence for the use of this tracer as an equivalent for generator-eluted 99mTc-NaTcO4 in routine clinical practice. © 2017 by the Society of Nuclear Medicine and Molecular Imaging.

  16. mA beam acceleration efforts on 100 MeV H- cyclotron at CIAE

    Science.gov (United States)

    Zhang, Tianjue; An, Shizhong; Lv, Yinlong; Ge, Tao; Jia, Xianlu; Ji, Bin; Yin, Zhiguo; Pan, Gaofeng; Cao, Lei; Guan, Fengping; Yang, Jianjun; Li, Zhenguo; Zhao, Zhenlu; Wu, Longcheng; Zhang, He; Wang, Jingfeng; Zhang, Yiwang; Liu, Jingyuan; Li, Shiqiang; Lu, Xiaotong; Liu, Zhenwei; Li, Yaoqian; Guo, Juanjuan; Cao, Xuelong; Guan, Leilei; Wang, Fei; Wang, Yang; Yang, Guang; Zhang, Suping; Hou, Shigang; Wang, Feng

    2017-09-01

    Various technologies for high current compact H- cyclotron have been developed at CIAE since 1990s. A 375 μA proton beam was extracted from a 30 MeV compact H- cyclotron CYCIAE-30 at the end of 1994. A central region model cyclotron CYCIAE-CRM was developed for the design verification of a 100 MeV high current compact H- cyclotron CYCIAE-100. It is also a 10 MeV proton machine as a prototype for PET application. A 430 μA beam was achieved in 2009. The first beam was extracted from the CYCIAE-100 cyclotron on July 4, 2014, the operation stability has been improved and beam current has been increased gradually. A 1.1 mA proton beam was measured on the internal target in July 2016. The effort for an increasing of proton beam has continued till now. In this paper, the effort on several aspects for mA beam development will be presented, including the multi-cusp source, buncher, matching from the energy of the injected beam, vertical beam line and central region, beam loading of the RF system and instrumentation for beam diagnostics etc.

  17. The Nuclear Security Science and Policy Institute at Texas A&M University

    Directory of Open Access Journals (Sweden)

    Claudio A. Gariazzo

    2015-07-01

    Full Text Available The Nuclear Security Science and Policy Institute (NSSPI is a multidisciplinary organization at Texas A&M University and was the first U.S. academic institution focused on technical graduate education, research, and service related to the safeguarding of nuclear materials and the reduction of nuclear threats. NSSPI employs science, engineering, and policy expertise to: (1 conduct research and development to help detect, prevent, and reverse nuclear and radiological proliferation and guard against nuclear terrorism; (2 educate the next generation of nuclear security and nuclear nonproliferation leaders; (3 analyze the interrelationships between policy and technology in the field of nuclear security; and (4 serve as a public resource for knowledge and skills to reduce nuclear threats. Since 2006, over 31 Doctoral and 73 Master degrees were awarded through NSSPI-sponsored research. Forty-one of those degrees are Master of Science in Nuclear Engineering with a specialization in Nuclear Nonproliferation and 16 were Doctorate of Philosophy degrees with a specific focus on nuclear nonproliferation. Over 200 students from both technical and policy backgrounds have taken classes provided by NSSPI at Texas A&M. The model for creating safeguards and security experts, which has in large part been replicated worldwide, was established at Texas A&M by NSSPI faculty and staff. In addition to conventional classroom lectures, NSSPI faculty have provided practical experiences; advised students on valuable research projects that have contributed substantially to the overall nuclear nonproliferation, safeguards and security arenas; and engaged several similar academic and research institutes around the world in activities and research for the benefit of Texas A&M students. NSSPI has had an enormous impact on the nuclear nonproliferation workforce (across the international community in the past 8 years, and this paper is an attempt to summarize the activities

  18. Laser Safety Program Development at Texas A&M University--Issues and Challenges.

    Science.gov (United States)

    Vasudevan, Latha; Menchaca, Daniel I; Tutt, James

    2015-09-01

    Implementing a laser safety program within a University setting encompassing a wide variety of Class 3b and Class 4 lasers with varied potential uses introduces many challenges. Texas A&M University (TAMU) currently has over 310 laser units that are registered with the Texas Department of State Health Services (TDSHS). One primary task in maintaining the laser registration is to have a program that identifies the regulatory responsibilities of the registrant. The Radiological Safety Staff, a part of Environmental Health and Safety (EHS), administers the use of both ionizing and non-ionizing radiation. The Radiological Safety Officer (RSO)/Laser Safety Officer (LSO) maintains the laser registration. This article outlines key elements that were put forth in the development and implementation of the laser safety program at TAMU.

  19. Texas A&M Physics Festival: bringing together the community, faculty, and students

    Science.gov (United States)

    Erukhimova, Tatiana

    Texas A&M Physics Festival started in 2003 with a dozen of hands-on exhibits and an inaugural lecture by Stephen Hawking. Over the years it evolved into one of the largest STEM outreach events in the area. The Festival attracts over 4000 visitors annually from all over Texas and other states. It features over 100 interactive exhibits displayed by faculty and students, public lectures by world-renowned scientists and astronauts, professional bubble shows, and many other activities. I will report on the structure of the Festival as well as strategies for involving undergraduate and graduate students and faculty in public outreach. I will further discuss the results of an independent evaluation of the 2015 Festival by the NSF-funded EvalFest program.

  20. Engineering and management experience at Texas A&M Transportation Institute

    Science.gov (United States)

    Chowdhury, Arif Tahjibul

    This manuscript presents the author's engineering and management experience during his internship in the Materials and Pavements (M&P) Division at the Texas A&M Transportation Institute (TTI), and is a record of study for the Doctor of Engineering at Texas A&M University. Through this internship, he met his established internship objectives of gaining technical knowledge as well as knowledge and skills in project management, organizational communication, and quality management of pavement condition data, and of attaining professional development. In meeting these objectives, the author describes the history, mission, and organizational structure of his workplace. He also presents his experience of developing and delivering a two-week training course on pavement design and construction in Kosovo. Participating in a number of professional development training courses and other activities prepared him for working as an engineering manager. These activities include Delta-T leadership training, an instructor development course, a time management and organizational skills course, and the M&P Division lecture series. Leadership and skills learned through the Delta-T program were beneficial for the employee as well as the employer. For the class project, the author and his teammates performed a study dealing with improving TTI's deliverables. The Delta-T team composed a report summarizing their efforts of examining the current state of TTI's project deliverables, the deliverables' shortcomings, and potential enhancements to expand the deliverables' appeal to additional types of potential users outside the traditional research community. The team also developed a prototype web-based model of deliverables and presented some implementation recommendations. Participating in the Texas Department of Transportation's (TxDOT's) pavement surface distress data collection program enabled the author to become familiar with pavement distress data quality management and thus attain the

  1. Development of a fast scintillator based beam phase measurement system for compact superconducting cyclotrons

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharjee, Tanushyam; Kanti Dey, Malay; Dhara, Partha; Roy, Suvodeep; Debnath, Jayanta; Balakrishna Bhole, Rajendra; Dutta, Atanu; Pradhan, Jedidiah; Pal, Sarbajit; Pal, Gautam; Roy, Amitava; Chakrabarti, Alok [Variable Energy Cyclotron Centre, 1/AF Bidhannagar, Kolkata 700064 (India)

    2013-05-15

    In an isochronous cyclotron, measurements of central phase of the ion beam with respect to rf and the phase width provide a way to tune the cyclotron for maximum energy gain per turn and efficient extraction. We report here the development of a phase measurement system and the measurements carried out at the Variable Energy Cyclotron Centre's (VECC's) K= 500 superconducting cyclotron. The technique comprises detecting prompt {gamma}-rays resulting from the interaction of cyclotron ion beam with an aluminium target mounted on a radial probe in coincidence with cyclotron rf. An assembly comprising a fast scintillator and a liquid light-guide inserted inside the cyclotron was used to detect the {gamma}-rays and to transfer the light signal outside the cyclotron where a matching photo-multiplier tube was used for light to electrical signal conversion. The typical beam intensity for this measurement was a few times 10{sup 11} pps.

  2. Steven Hawking to visit Texas A&M in spring

    CERN Multimedia

    Xavier, D

    2002-01-01

    Stephen Hawking will visit Texas A&M University from Feb. 24 to March 21 2003 to participate in the inaugural meeting of the George P. and Cynthia W. Mitchell Institute for Fundamental Physics. This institute will bring several of the world's top physicists to A&M for a month-long exploration of the latest ideas on topics ranging from superstrings to M-theory and supergravity (1/2 page).

  3. Battling Carpal Tunnel Syndrome through Ergonomics: A Case Study of Texas A&M's Library Provides Insights and Answers.

    Science.gov (United States)

    Thornton, Joyce K.

    1995-01-01

    Current library automation practices and new technologies have forced library managers to seek some means of reducing carpal tunnel syndrome, and a case study of Texas A&M's library provides insights. Highlights include identifying and assessing the injuries, adjusting work surfaces, testing and selecting new keyboards, and developing…

  4. 75 FR 36710 - The Texas Engineering Experiment Station/Texas A&M University System; Notice of Acceptance for...

    Science.gov (United States)

    2010-06-28

    ... COMMISSION The Texas Engineering Experiment Station/Texas A&M University System; Notice of Acceptance for... Facility Operating License No. R-83 (``Application''), which currently authorizes the Texas Engineering Experiment Station/Texas A&M University System (TEES, the licensee) to operate the Nuclear Science Center...

  5. Radioisotopic Purity of Sodium Pertechnetate 99mTc Produced with a Medium-Energy Cyclotron: Implications for Internal Radiation Dose, Image Quality, and Release Specifications.

    Science.gov (United States)

    Selivanova, Svetlana V; Lavallée, Éric; Senta, Helena; Caouette, Lyne; Sader, Jayden A; van Lier, Erik J; Zyuzin, Alexander; van Lier, Johan E; Guérin, Brigitte; Turcotte, Éric; Lecomte, Roger

    2015-10-01

    Cyclotron production of 99mTc is a promising route to supply 99mTc radiopharmaceuticals. Higher 99mTc yields can be obtained with medium-energy cyclotrons in comparison to those dedicated to PET isotope production. To take advantage of this capability, evaluation of the radioisotopic purity of 99mTc produced at medium energy (20-24 MeV) and its impact on image quality and dosimetry was required. Thick 100Mo (99.03% and 99.815%) targets were irradiated with incident energies of 20, 22, and 24 MeV for 2 or 6 h. The targets were processed to recover an effective thickness corresponding to approximately 5-MeV energy loss, and the resulting sodium pertechnetate 99mTc was assayed for chemical, radiochemical, and radionuclidic purity. Radioisotopic content in final formulation was quantified using γ-ray spectrometry. The internal radiation dose for 99mTc-pertechnetate was calculated on the basis of experimentally measured values and biokinetic data in humans. Planar and SPECT imaging were performed using thin capillary and water-filled Jaszczak phantoms. Extracted sodium pertechnetate 99mTc met all provisional quality standards. The formulated solution for injection had a pH of 5.0-5.5, contained greater than 98% of radioactivity in the form of pertechnetate ion, and was stable for at least 24 h after formulation. Radioisotopic purity of 99mTc produced with 99.03% enriched 100Mo was greater than 99.0% decay corrected to the end of bombardment (EOB). The radioisotopic purity of 99mTc produced with 99.815% enriched 100Mo was 99.98% or greater (decay corrected to the EOB). The estimated dose increase relative to 99mTc without any radionuclidic impurities was below 10% for sodium pertechnetate 99mTc produced from 99.03% 100Mo if injected up to 6 h after the EOB. For 99.815% 100Mo, the increase in effective dose was less than 2% at 6 h after the EOB and less than 4% at 15 h after the EOB when the target was irradiated at an incident energy of 24 MeV. Image spatial resolution

  6. Direct production of 99mTc using a small medical cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Lapi, Suzanne [Washington Univ., St. Louis, MO (United States)

    2017-10-03

    This project describes an investigation towards the production of 99mTc with a small medical cyclotron. This endeavor addresses the current urgent problem of availability of 99mTc due to the ongoing production reactor failures and the upcoming Canadian reactor shut down. Currently, 99mTc is produced via nuclear fission using highly enriched uranium which is a concern due to nuclear proliferation risks. In addition to this, the United States is dependent solely on currently unreliable foreign sources of this important medical isotope. Clearly, a need exists to probe alternative production routes of 99mTc. In the first year, this project measured cross-sections and production yields of potential pathways to 99mTc and associated radionuclidic impurities produced via these pathways using a small 15 MeV medical cyclotron. During the second and third years target systems for the production of 99mTc via the most promising reaction routes were developed and separation techniques for the isolation of 99mTc from the irradiated target material will be investigated. Systems for the recycling of the enriched target isotopes as well as automated target processing systems were examined in years four and five. This project has the potential to alleviate some of the current crisis in the medical community by developing a technique to produce 99mTc on location at a university hospital. This technology will be applicable at many other sites in the United States as many other similar, low energy (<20 MeV) cyclotrons (currently used for a few hours per day for the production of [18F]fluorodeoxyglucose) are available for production of 99mTc though this method, thus leading to job creation and preservation.

  7. A fast and simple dose-calibrator-based quality control test for the radionuclidic purity of cyclotron-produced (99m)Tc.

    Science.gov (United States)

    Tanguay, J; Hou, X; Esquinas, P; Vuckovic, M; Buckley, K; Schaffer, P; Bénard, F; Ruth, T J; Celler, A

    2015-11-07

    Cyclotron production of 99mTc through the (100)Mo(p,2n)99mTc reaction channel is actively being investigated as an alternative to reactor-based (99)Mo generation by nuclear fission of (235)U. Like most radioisotope production methods, cyclotron production of 99mTc will result in creation of unwanted impurities, including Tc and non-Tc isotopes. It is important to measure the amounts of these impurities for release of cyclotron-produced 99mTc (CPTc) for clinical use. Detection of radioactive impurities will rely on measurements of their gamma (γ) emissions. Gamma spectroscopy is not suitable for this purpose because the overwhelming presence of 99mTc and the count-rate limitations of γ spectroscopy systems preclude fast and accurate measurement of small amounts of impurities. In this article we describe a simple and fast method for measuring γ emission rates from radioactive impurities in CPTc. The proposed method is similar to that used to identify (99)Mo breakthrough in generator-produced 99mTc: one dose calibrator (DC) reading of a CPTc source placed in a lead shield is followed by a second reading of the same source in air. Our experimental and theoretical analysis show that the ratio of DC readings in lead to those in air are linearly related to γ emission rates from impurities per MBq of 99mTc over a large range of clinically-relevant production conditions. We show that estimates of the γ emission rates from Tc impurities per MBq of 99mTc can be used to estimate increases in radiation dose (relative to pure 99mTc) to patients injected with CPTc-based radiopharmaceuticals. This enables establishing dosimetry-based clinical-release criteria that can be tested using commercially-available dose calibrators. We show that our approach is highly sensitive to the presence of 93gTc, 93mTc, 94gTc, 94mTc, 95mTc, 95gTc, and 96gTc, in addition to a number of non-Tc impurities.

  8. A solvent-extraction module for cyclotron production of high-purity technetium-99m.

    Science.gov (United States)

    Martini, Petra; Boschi, Alessandra; Cicoria, Gianfranco; Uccelli, Licia; Pasquali, Micòl; Duatti, Adriano; Pupillo, Gaia; Marengo, Mario; Loriggiola, Massimo; Esposito, Juan

    2016-12-01

    The design and fabrication of a fully-automated, remotely controlled module for the extraction and purification of technetium-99m (Tc-99m), produced by proton bombardment of enriched Mo-100 molybdenum metallic targets in a low-energy medical cyclotron, is here described. After dissolution of the irradiated solid target in hydrogen peroxide, Tc-99m was obtained under the chemical form of 99mTcO4-, in high radionuclidic and radiochemical purity, by solvent extraction with methyl ethyl ketone (MEK). The extraction process was accomplished inside a glass column-shaped vial especially designed to allow for an easy automation of the whole procedure. Recovery yields were always >90% of the loaded activity. The final pertechnetate saline solution Na99mTcO4, purified using the automated module here described, is within the Pharmacopoeia quality control parameters and is therefore a valid alternative to generator-produced 99mTc. The resulting automated module is cost-effective and easily replicable for in-house production of high-purity Tc-99m by cyclotrons. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Steps Towards a 3 mA, 1.8 MW Proton Beam at the PSI Cyclotron Facility

    CERN Document Server

    Schmelzbach, Pierre A; Adelmann, Andreas; Fitze, Hansruedi; Heidenreich, Gerd; Raguin, Jean-Yves; Rohrer, Urs; Sigg, Peter K

    2005-01-01

    The PSI Cyclotron Facility produces routinely a 1.8-1.9 mA proton beam at 590 MeV. The beam power reaches 1.1 MW at the the pion production targets and 0.7 MW at the neutron spallation target SINQ. The accelerator complex will be analysed in respect to his potential for future improvements. The ongoing developments aiming to increase the beam intensity to 3 mA and hence the beam power to 1.8 MW will be discussed. Smooth extrapolations of the observed machine parameters as well as recent advances in the theoretical treatment of space charge dominated beams show that this goal can be achieved with available technologies. IA new RF-cavity operated at a voltage in excess of 1 MV has been successfully tested and installed in the Ring Cyclotron. Bunchers for the low energy and the medium energy transfer lines are in the design phase. A conceptual study of new accelerating cavities to replace the obsolete flattop-cavities of the Injector Cyclotron has been performed. While the upgrade of the Ring Cyclotron with four...

  10. Texas A&M University Industrial Assessment Center Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Heffington, Warren M.; Eggebrecht, James A.

    2007-02-24

    This project benefited the public by assisting manufacturing plants in the United States to save costly energy resources and become more profitable. Energy equivalent to over 75,000 barrels of oil was conserved. The Texas A&M University Industrial Assessment Center (IAC) visited 96 manufacturing plants and spent 101 days in those plants during the contract period from August 9, 2002, through November 30, 2006. Recommended annual energy savings for manufacturers were 37,400,000 kWh (127,600 MMBtu—site basis) of electricity and 309,000 MCF (309,000 MMBtu) of natural gas. Each manufacturer subsequently was surveyed, and based on these surveys reportedly implemented 79% of the electricity savings and 36% of the natural gas savings for an overall energy savings of 48% of recommended. Almost 800 (798) projects were recommended to manufacturers, and they accomplished two-thirds of the projects. Cost savings recommended were $12.3 million and implemented savings were $5.7 million or 47%. During the contract period our average time between site visit and report submittal averaged 46 days; and decreased from 48 days in 2003 to 44 days in 2006. Serving clients well and promptly has been a priority. We visited five ESA overflow clients during FY 06. The Texas A&M University IAC pioneered the presentation of air pollution information in reports, and includes NOx and CO2 reductions due to energy savings in all reports. We also experimented with formal PowerPoint BestPractices presentations called Lunchtime/Showtime in each plant and with delivering electronic versions of the report. During the period of the contract, the director served on the Texas Industries of the Future (IOF) Refining and Chemicals Committee, which oversaw the showcases in 2003 and 2006. The assistant director was the Executive Director of the International Energy Technology Conference held annually. The director and assistant director became qualified specialists in the Process Heating Assessment Scoping

  11. A study of three-half-turn and frame antennae for ion cyclotron range of frequency plasma heating in the URAGAN-3M torsatron

    Energy Technology Data Exchange (ETDEWEB)

    Lysoivan, A.I. [Kharkov Inst. of Phys. and Tech. (Ukraine). Nat. Sci. Center; Moiseenko, V.E. [Kharkov Inst. of Phys. and Tech. (Ukraine). Nat. Sci. Center; Plyusnin, V.V. [Kharkov Inst. of Phys. and Tech. (Ukraine). Nat. Sci. Center; Kasilov, S.V. [Kharkov Inst. of Phys. and Tech. (Ukraine). Nat. Sci. Center; Bondarenko, V.N. [Kharkov Inst. of Phys. and Tech. (Ukraine). Nat. Sci. Center; Chechkin, V.V. [Kharkov Inst. of Phys. and Tech. (Ukraine). Nat. Sci. Center; Fomin, I.P. [Kharkov Inst. of Phys. and Tech. (Ukraine). Nat. Sci. Center; Grigor`eva, L.I. [Kharkov Inst. of Phys. and Tech. (Ukraine). Nat. Sci. Center; Konovalov, V.G. [Kharkov Inst. of Phys. and Tech. (Ukraine). Nat. Sci. Center; Koval`ov, S.V. [Kharkov Inst. of Phys. and Tech. (Ukraine). Nat. Sci. Center; Litvinov, A.P. [Kharkov Inst. of Phys. and Tech. (Ukraine). Nat. Sci. Center; Mironov, Yu.K. [Kharkov Inst. of Phys. and Tech. (Ukraine). Nat. Sci. Center; Nazarov, N.I. [Kharkov Inst. of Phys. and Tech. (Ukraine). Nat. Sci. Center; Pavlichenko, O.S. [Kharkov Inst. of Phys. and Tech. (Ukraine). Nat. Sci. Center; Pavlichenko, R.O. [Kharkov Inst. of Phys. and Tech. (Ukraine). Nat. Sci. Center; Shapoval, A.N. [Kharkov Inst. of Phys. and Tech. (Ukraine). Nat. Sci. Center; Skibenko, A.I. [Kharkov Inst. of Phys. and Tech. (Ukraine). Nat. Sci. Center; Volkov, E.D. [Kharkov Inst. of Phys. and Tech. (Ukraine). Nat. Sci. Center

    1995-01-01

    Numerical and experimental results of Alfven wave heating of plasmas in the frequency range below the ion cyclotron frequency ({omega}<{omega}{sub ci}) are presented. Two different types of antenna were used for plasma production and heating: a frame type antenna (FTA) conventionally used in the URAGAN-3M device and a three-half-turn antenna (THTA) proposed recently to avoid the deleterious effects of conversion of fast wave to slow wave in the plasma periphery and to perform plasma core heating more effectively. Numerical modeling of electromagnetic field excitation in the URAGAN-3M plasma by the FTA and THTA was performed using a one-dimensional code. The results of calculations showed better performance of the compact THTA compared with the FTA for the case of a high density plasma (approximately 10{sup 13}cm{sup -3}). When using the THTA, the experiments performed showed the possibility of dense plasma production (more than 2x10{sup 13}cm{sup -3}) and heating, which had not been obtained earlier in the URAGAN-3M. Shifting the power deposition profile deeper inside the plasma body with the THTA resulted in modification of the plasma density profile and an improvement in plasma confinement. ((orig.)).

  12. Final report for Texas A&M University Group Contribution to DE-FG02-09ER25949/DE-SC0002505: Topology for Statistical Modeling of Petascale Data (and ASCR-funded collaboration between Sandia National Labs, Texas A&M University and University of Utah)

    Energy Technology Data Exchange (ETDEWEB)

    Rojas, Joseph Maurice [Texas A& M University

    2013-02-27

    We summarize the contributions of the Texas A\\&M University Group to the project (DE-FG02-09ER25949/DE-SC0002505: Topology for Statistical Modeling of Petascale Data - an ASCR-funded collaboration between Sandia National Labs, Texas A\\&M U, and U Utah) during 6/9/2011 -- 2/27/2013.

  13. History of the discovery of transmutation at Texas A and M University

    Energy Technology Data Exchange (ETDEWEB)

    Bockris, J.O.M. [Molecular Green Technology, College Station, TX 77845 (United States)

    2006-07-01

    Until 1989, to author was a publisher of high temperature physical chemistry, electrochemical and environmental research papers. He was a physical chemist and his contact with nuclear chemistry was only in using it in some tracer techniques. The Fleischmann and Pons announcement of March 1989 was of interest partly because of its radical nature) but also because the author has known Martin Fleischmann since his days as a student at the Imperial College of Science and Technology in London. He had easy access to Fleischmann and he therefore could instruct his co-workers (about 20 at the time) about the technique used in the Fleischmann and Pons work. It was around 3 weeks before they were able to detect strong concentrations of tritium in the solution after prolonged electrolysis and thus prove, for the first time, that the speculation which Fleischmann and Pons had made about their excess heat was indeed; correct and that a nuclear reaction was occurring at or in an electrode in the cold. They continued to work on the new nuclear phenomena, in 1991 discovering excess {sup 4}He in their palladium cathodes. Later in 1991, the author received a phone call from a Joseph Champion. He told him that the long initiation times which he had recorded in its papers could be avoided and that he could 'turn on' what he described as a 'radioactive gas' in less than 1 h. Champion invited him to visit his laboratory (which was in a trailer on the grounds of the University of Tennessee). He could operate his apparatus and see for himself. He asked Dr. Ramesh Kainthla and Mr. Omo Velev, senior researchers in my laboratory, to visit Champion and see if his statements could be confirmed. Upon return to Texas A and M, they told the author that Champion had left them alone in the so-called laboratory, pointed to the apparatus, gave them a few instructions about turning it on, and left them alone. They measured 40% of the excess heat, that he had said was obtainable

  14. Technical note: building a combined cyclotron and MRI facility: implications for interference.

    Science.gov (United States)

    Hofman, Mark B M; Kuijer, Joost P A; de Ridder, Jan Willem; Perk, Lars R; Verdaasdonk, Rudolf M

    2013-01-01

    With the introduction of hybrid PET∕MRI systems, it has become more likely that the cyclotron and MRI systems will be located close to each other. This study considered the interference between a cyclotron and a superconducting MRI system. Interactions between cyclotrons and MRIs are theoretically considered. The main interference is expected to be the perturbation of the magnetic field in the MRI due to switching on or off the magnetic field of the cyclotron. MR imaging is distorted by a dynamic spatial gradient of an external inplane magnetic field larger than 0.5-0.04 μT∕m, depending on the specific MR application. From the design of a cyclotron, it is expected that the magnetic fringe field at large distances behaves as a magnetic dipolar field. This allows estimation of the full dipolar field and its spatial gradients from a single measurement. Around an 18 MeV cyclotron (Cyclone, IBA), magnetic field measurements were performed on 5 locations and compared with calculations based upon a dipolar field model. At the measurement locations the estimated and measured values of the magnetic field component and its spatial gradients of the inplane component were compared, and found to agree within a factor 1.1 for the magnetic field and within a factor of 1.5 for the spatial gradients of the field. In the specific case of the 18 MeV cyclotron with a vertical magnetic field and a 3T superconducting whole body MR system, a minimum distance of 20 m has to be considered to prevent interference. This study showed that a dipole model is sufficiently accurate to predict the interference of a cyclotron on a MRI scanner, for site planning purposes. The cyclotron and a whole body MRI system considered in this study need to be placed more than 20 m apart, or magnetic shielding should be utilized.

  15. Technical Note: Building a combined cyclotron and MRI facility: Implications for interference

    Energy Technology Data Exchange (ETDEWEB)

    Hofman, Mark B. M.; Kuijer, Joost P. A.; Ridder, Jan Willem de; Perk, Lars R.; Verdaasdonk, Rudolf M. [Physics and Medical Technology, VU University Medical Center, Amsterdam 1007 MB (Netherlands) and BV Cyclotron VU, Amsterdam 1081HV (Netherlands)

    2013-01-15

    Purpose: With the introduction of hybrid PET/MRI systems, it has become more likely that the cyclotron and MRI systems will be located close to each other. This study considered the interference between a cyclotron and a superconducting MRI system. Methods: Interactions between cyclotrons and MRIs are theoretically considered. The main interference is expected to be the perturbation of the magnetic field in the MRI due to switching on or off the magnetic field of the cyclotron. MR imaging is distorted by a dynamic spatial gradient of an external inplane magnetic field larger than 0.5-0.04 {mu}T/m, depending on the specific MR application. From the design of a cyclotron, it is expected that the magnetic fringe field at large distances behaves as a magnetic dipolar field. This allows estimation of the full dipolar field and its spatial gradients from a single measurement. Around an 18 MeV cyclotron (Cyclone, IBA), magnetic field measurements were performed on 5 locations and compared with calculations based upon a dipolar field model. Results: At the measurement locations the estimated and measured values of the magnetic field component and its spatial gradients of the inplane component were compared, and found to agree within a factor 1.1 for the magnetic field and within a factor of 1.5 for the spatial gradients of the field. In the specific case of the 18 MeV cyclotron with a vertical magnetic field and a 3T superconducting whole body MR system, a minimum distance of 20 m has to be considered to prevent interference. Conclusions: This study showed that a dipole model is sufficiently accurate to predict the interference of a cyclotron on a MRI scanner, for site planning purposes. The cyclotron and a whole body MRI system considered in this study need to be placed more than 20 m apart, or magnetic shielding should be utilized.

  16. Transfer student and gender issues within the Department of Animal Science at Texas A&M University.

    Science.gov (United States)

    Cleer, J J; Minney, B A; Johnson, B H; Murano, P S; Briers, G E; Greathouse, T R

    2000-12-01

    Graduates with a B.S. or graduate degree from the Department of Animal Science (1986 to 1996) of Texas A&M University were surveyed by mail to gather opinions on the curriculum and satisfaction with their degrees. The survey contained five Likert questions (1 = excellent, 4 = poor) regarding satisfaction with major, educational results, personal growth, professional development, and skills important for employment. Multiple-choice questions (n = 9) addressed education, background, job status, and gender. Surveys (n = 2,192) were sent to students, and 470 responded. The undergraduate respondents (n = 396) comprised 71.2% (n = 282) nontransfer students and 28.8% (n = 114) transfer students. Transfer students reported a mean grade point ratio (GPR) of 3.05 +/- 0.43 at Texas A&M University in comparison to a nontransfer student mean GPR of 3.03 +/- 0.45 for hours completed at Texas A&M University (P = 0.83). The results for time from graduation to full-time employment for transfer students were similar to those of nontransfer students (P = 0.95). Differences in current annual salary between transfer students and nontransfer students were apparent (P job search time (P job. Males and females responded similarly that courses were valuable (P = 0.16) and were taught effectively (P = 0.37) and that teaching assistants made positive contributions (P = 0.43). Females felt a lesser contribution to critical thinking ability, leadership ability, and technical expertise. Results suggest the continuance of current educational practices, but changes to specific issues should be initiated.

  17. Mechanism-Based Modeling of Hydrogen Environment Assisted Cracking (HEAC) in High Strength Alloys for Marine Applications: Prediction of Monel K-500 HEAC for Select Environmental and Mechanical Conditions

    Science.gov (United States)

    2012-10-15

    interactions with plastic deformation . The model outputs will be KTH and da/dtn, each as a function of material and electrochemical conditions. Such...Lopez, M. Rodriguez, A. Martinez-Villafane and J.M. Bastidas, Cement & Concrete Composites, 34, p. 242-247 (2012) 7. T. Kamimura and H. Kishikawa...change with aging [2]. M23C6 carbides where M=Mn, Fe, or Ni form on isolated grain boundaries in Monel K-500 aged for long times. Lastly, annealing

  18. Texas flexible pavements and overlays : calibration plans for M-E models and related software.

    Science.gov (United States)

    2013-06-01

    This five-year project was initiated to collect materials and pavement performance data on a minimum of 100 highway test sections around the State of Texas, incorporating flexible pavements and overlays. Besides being used to calibrate and validate m...

  19. Analysis of the Cyclotron Facility Calibration and Aircraft Results Obtained by LIULIN-3M Instrument

    Science.gov (United States)

    Dachev, T. P.; Stassinopoulos, E. G.; Tomov, B. T.; Dimitrov, P. G.; Matviichuk, Y. N.; Shurshakov, V. A.; Petrov, V. M.

    1998-01-01

    The LIULIN-3M instrument is a further development of the LIULIN dosimeter-radiometer, which has been used on the NffR space station in the 1988-1994 time period, The LIULIN-3M is designed for continuous monitoring of the radiation environment during the BION-12 satellite flight in 1999. A semiconductor detector with 1 mm thickness and 1 cm(exp 2) area is used in the instrument. Pulse high analysis technique is used for measurement of the energy losses in the detector. The final data sets from the instrument are the flux and the dose rate for the exposition time and 256 channels of LET spectra if a non-nal coincidence of the particles to the detector is considered. The LIULIN-3M instrument was calibrated by proton fluxes with different energies at the Indiana University Cyclotron Facility in June 1997 and was used for space radiation measurements during commercial aircraft flights. Obtained calibration and flight results are analyzed in the paper.

  20. Analysis of the Cyclotron Facility calibration and aircraft dosimetry results from the LIULIN-3M instrument.

    Science.gov (United States)

    Dachev, Ts P; Stassinopoulous, E G; Tomov, B T; Dimitrov, Pl G; Matviichuk, Yu N; Shurshakov, V A; Petrov, V M

    2003-01-01

    The LIULIN-3M instrument is a further development of the LIULIN dosimeter-radiometer, used on the MIR spacestation during the 1988-1994 time period. The LIULIN-3M is designed for continuous monitoring of the radiation environment during the BION-12 satellite flight in 1999. A semiconductor detector with 1 mm thickness and cm2 area is contained in the instrument. Pulse high analysis technique is used to determine the energy losses in the detector. The final data from the instrument are the flux and the dose rate for the exposure time and 256 channels of absorbed dose spectra based on the assumption that the particle flux is normal to the detector. The LIULIN-3M instrument was calibrated by proton fluxes with different energies at the Indiana University Cyclotron Facility in June 1997 and had been used for radiation measurements during commercial aircraft flights. The calibration procedure and some flight results are presented in this paper. c2003 COSPAR. Published by Elsevier Ltd. All rights reserved.

  1. High energy physics program at Texas A and M University. Annual report, April 1, 1991--March 31, 1992

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    The Texas A&M experimental high energy physics program continued to reach significant milestones in each of its research initiatives during the course of the past year. We are participating in two major operating experiments, CDF and MACRO. In CDF, the Texas A&M group has spearheaded the test beam program to recalibrate the Forward Hadron Calorimeter for the upcoming CDF data run, as well as contributing to the ongoing analysis work on jets and b-quarks. In MACRO, we have assisted in the development of the final version of the wave form digitizing system being implemented for the entire scintillator system. The construction of the first six supermodules of the detector has been completed and all six are currently taking data with streamer chambers while four have the completed scintillator counter system up and running. We have built and tested prototypes of a liquid-scintillator fiber calorimeter system, in which internally reflecting channels are imbedded in a lead matrix and filled with liquid scintillator. This approach combines the performance features of fiber calorimetry and the radiation hardness of liquid scintillator, and is being developed for forward calorimetry at the SSC. The microstrip chamber is a new technology for precision track chambers that offers the performance required for future hadron colliders. The theoretical high energy physics program has continued to develop during the past funding cycle. We have continued the study of their very successful string-derived model that unifies all known interactions; flipped SU(5), which is the leading candidate for a TOE. Work has continued on some generalizations of the symmetries of string theory, known as W algebras. These are expected to have applications in two-dimensional conformal field theory, two-dimensional extensions of gravity and topological gravity and W-string theory.

  2. Design and Research of Electron Cyclotron Resonance Heating and Current Dive System on HL-2M Tokamak

    Science.gov (United States)

    Huang, Mei; Rao, Jao; Song, Shaodong; Wang, He; Chen, Gangyu; Kang, Zhihua; Zhang, Feng; Wang, Jieqiong; Ye, Jiruo; Feng, Kun; Lu, Bo; Huang, Bo; Wang, Chao; Wang, Mingwei; Xuan, Weimin; Rao, Lieying; Li, Qing; Mao, Xiaohui; Duan, Xuru; Liu, Yong

    2017-07-01

    A research has been conducted to develop an 8MW electron cyclotron resonance heating and current drive (ECRH/ECCD) system on HL-2M tokamak. The ECRH system compromise eight 1MW gyrotrons, eight evacuated transmission lines and three launchers. The main purpose of the ECRH system was to suppress the neo-classical tearing modes and control the plasma profile. This paper presents an overview of the design and studies performed in this framework. Some primary test results of the critical components have been released in this paper, e.g. polarizers, power monitor and fast steering launchers.

  3. Continuation application for the Amarillo National Resource Center for Plutonium, a higher education consortium consisting of Texas A and M University, Texas Tech University, and the University of Texas at Austin

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-06-29

    This report describes the 5 tasks to be covered under this project and compiles budget information. Task 1 is to establish a Plutonium Information Resource, which has been established in Amarillo, Texas. Task 2, Advisory Functions, coordinates studies and activities relating to the disposition of excess weapons-grade plutonium. Task 3, Environmental, Public Health, and Safety, supports soil remediation activities. Task 4, Education and Outreach, is supporting four programs: K--12 education improvement in science and math courses; Academic intervention to identify and encourage high ability high school and middle school students with potential to become scientists and engineers; Graduate education evaluation; and Public outreach programs. Task 5, Plutonium and other Materials Studies, is currently funding two projects for the disposition of high explosives: a feasibility study of burning a mixture of high explosives and other materials in a commercial coal-fired power plant and synthesis of diamond by shock compression of bucky ball with explosives.

  4. A Citation Analysis of Atmospheric Science Publications by Faculty at Texas A&M University

    Science.gov (United States)

    Kimball, Rusty; Stephens, Jane; Hubbard, David; Pickett, Carmelita

    2013-01-01

    A citation analysis of publications produced by the Department of Atmospheric Sciences faculty at Texas A&M University was conducted. This study included a detailed analysis of 5,082 cited publications by source, format, and age. TAMU Libraries holdings were then assessed using the works cited within the context of the 80/20 rule. The sources…

  5. A Suzaku View of Cyclotron Line Sources and Candidates

    Science.gov (United States)

    Pottschmidt, K.; Suchy, S.; Rivers, E.; Rothschild, R. E.; Marcu, D. M.; Barragan, L.; Kuehnel, M.; Fuerst, F.; Schwarm, F.; Kreykenbohm, I.; hide

    2012-01-01

    Seventeen accreting neutron star pulsars, mostly high mass X-ray binaries with half of them Be-type transients, are known to exhibit Cyclotron Resonance Scattering Features (CRSFs) in their X-ray spectra, with characteristic line energies from 10 to 60 keY. To date about two thirds of them, plus a few similar systems without known CRSFs, have been observed with Suzaku. We present an overview of results from these observations, including the discovery of a CRSF in the transient IA1118-61 and pulse phase resolved spectroscopy of OX 301-2. These observations allow for the determination of cyclotron line parameters to an unprecedented degree of accuracy within a moderate amount of observing time. This is important since these parameters vary - e.g., with orbital phase, pulse phase, or luminosity - depending on the geometry of the magnetic field of the pulsar and the properties of the accretion column at the magnetic poles. We briefly introduce a spectral model for CRSFs that is currently being developed and that for the first time is based on these physical properties. In addition to cyclotron line measurements, selected highlights from the Suzaku analyses include dip and flare studies, e.g., of 4U 1907+09 and Vela X-I, which show clumpy wind effects (like partial absorption and/or a decrease in the mass accretion rate supplied by the wind) and may also display magnetospheric gating effects.

  6. Collaboration in nuclear engineering education between France and the United States: Participation of French students at Texas A M University

    Energy Technology Data Exchange (ETDEWEB)

    Peddicord, K.L.; Durand, J.L.; Gousty, Y.; Jeneveau, A.; Erdman, C.A. (Texas A M Univ., College Station (USA))

    1988-01-01

    Universities in the United States have had a long tradition of accepting students from other countries to pursue graduate degrees. This has particularly been the case in the fields of engineering and science. This trend has grown to the point that in several graduate engineering fields, the percentage of foreign nationals outnumbers US enrollees. Historically, most foreign students studying in the US universities have been from developing countries. Usually these students apply and are accepted on a case-by-case basis. For a number of reasons, less emphasis has been placed on programs with western Europe. In this paper, a program of collaboration is described in which the Department of Nuclear Engineering at Texas A M University has entered into memoranda of agreement with two institutions in France. The two universities are the Institut National Polytechnique de Grenoble (INPG) in Grenoble and the Ecole Polytechnique Feminine (EPF) in Sceaux. The purpose of the program is to enable students in nuclear engineering to simultaneously complete requirements for the diploma and the MS degree.

  7. Toward a green campus : a transportation strategy for Texas A&M University.

    Science.gov (United States)

    2009-03-01

    This research study produces a recommended sustainable transportation implementation plan for Texas : A&M University (TAMU) to enhance the environmental performance of its campus transportation system. : To achieve the goal, this study followed a his...

  8. Texas A and M University student/professional nuclear science and engineering conference

    Energy Technology Data Exchange (ETDEWEB)

    1984-03-12

    Abstracts of papers presented at the meeting are included. Topics discussed include: reactor engineering; space nuclear power systems; health physics and dosimetry; fusion engineering and physics; and reactor physics and theory.

  9. Quantitative analysis of relationships between irradiation parameters and the reproducibility of cyclotron-produced (99m)Tc yields.

    Science.gov (United States)

    Tanguay, J; Hou, X; Buckley, K; Schaffer, P; Bénard, F; Ruth, T J; Celler, A

    2015-05-21

    Cyclotron production of (99m)Tc through the (100)Mo(p,2n) (99m)Tc reaction channel is actively being investigated as an alternative to reactor-based (99)Mo generation by nuclear fission of (235)U. An exciting aspect of this approach is that it can be implemented using currently-existing cyclotron infrastructure to supplement, or potentially replace, conventional (99m)Tc production methods that are based on aging and increasingly unreliable nuclear reactors. Successful implementation will require consistent production of large quantities of high-radionuclidic-purity (99m)Tc. However, variations in proton beam currents and the thickness and isotopic composition of enriched (100)Mo targets, in addition to other irradiation parameters, may degrade reproducibility of both radionuclidic purity and absolute (99m)Tc yields. The purpose of this article is to present a method for quantifying relationships between random variations in production parameters, including (100)Mo target thicknesses and proton beam currents, and reproducibility of absolute (99m)Tc yields (defined as the end of bombardment (EOB) (99m)Tc activity). Using the concepts of linear error propagation and the theory of stochastic point processes, we derive a mathematical expression that quantifies the influence of variations in various irradiation parameters on yield reproducibility, quantified in terms of the coefficient of variation of the EOB (99m)Tc activity. The utility of the developed formalism is demonstrated with an example. We show that achieving less than 20% variability in (99m)Tc yields will require highly-reproducible target thicknesses and proton currents. These results are related to the service rate which is defined as the percentage of (99m)Tc production runs that meet the minimum daily requirement of one (or many) nuclear medicine departments. For example, we show that achieving service rates of 84.0%, 97.5% and 99.9% with 20% variations in target thicknesses requires producing on average

  10. Quantitative analysis of relationships between irradiation parameters and the reproducibility of cyclotron-produced 99mTc yields

    Science.gov (United States)

    Tanguay, J.; Hou, X.; Buckley, K.; Schaffer, P.; Bénard, F.; Ruth, T. J.; Celler, A.

    2015-05-01

    Cyclotron production of 99mTc through the 100Mo(p,2n) 99mTc reaction channel is actively being investigated as an alternative to reactor-based 99Mo generation by nuclear fission of 235U. An exciting aspect of this approach is that it can be implemented using currently-existing cyclotron infrastructure to supplement, or potentially replace, conventional 99mTc production methods that are based on aging and increasingly unreliable nuclear reactors. Successful implementation will require consistent production of large quantities of high-radionuclidic-purity 99mTc. However, variations in proton beam currents and the thickness and isotopic composition of enriched 100Mo targets, in addition to other irradiation parameters, may degrade reproducibility of both radionuclidic purity and absolute 99mTc yields. The purpose of this article is to present a method for quantifying relationships between random variations in production parameters, including 100Mo target thicknesses and proton beam currents, and reproducibility of absolute 99mTc yields (defined as the end of bombardment (EOB) 99mTc activity). Using the concepts of linear error propagation and the theory of stochastic point processes, we derive a mathematical expression that quantifies the influence of variations in various irradiation parameters on yield reproducibility, quantified in terms of the coefficient of variation of the EOB 99mTc activity. The utility of the developed formalism is demonstrated with an example. We show that achieving less than 20% variability in 99mTc yields will require highly-reproducible target thicknesses and proton currents. These results are related to the service rate which is defined as the percentage of 99mTc production runs that meet the minimum daily requirement of one (or many) nuclear medicine departments. For example, we show that achieving service rates of 84.0%, 97.5% and 99.9% with 20% variations in target thicknesses requires producing on average 1.2, 1.5 and 1.9 times the

  11. An automated module for the separation and purification of cyclotron-produced 99mTcO4-.

    Science.gov (United States)

    Morley, Thomas J; Dodd, Maurice; Gagnon, Katherine; Hanemaayer, Vicky; Wilson, John; McQuarrie, Stephen A; English, Wade; Ruth, Thomas J; Bénard, François; Schaffer, Paul

    2012-05-01

    The shortage of reactor-produced molybdenum-99 ((99)Mo, t(½)=66 h) has renewed interest in alternative production methods of its daughter isotope, technetium-99m ((99m)Tc, t(½)=6.02 h). While adsorption chromatography serves as a mechanism for selective elution of sodium pertechnetate from technetium generators, this method of purification is not sufficient for many alternative production methods. Several ion-separation/solid phase extraction chromatography methods are known, yet none have been demonstrated on cyclotron-produced [(99m)Tc]TcO(4)(-). Herein we describe the design, manufacture and optimization of a remotely operated module for the purification of sodium pertechnetate from a bulk solution of molybdate. The automated purification module was designed to separate [(99m)Tc]TcO(4)(-) using either Dowex 1x8 or an Aqueous Biphasic Extraction Chromatography (ABEC) resin. (100)Mo composite targets were irradiated with 18.5 MeV protons for 10 μA·h using an ASCI TR19 cyclotron. Once purified, the radiopharmaceutical quality of (99m)TcO(4)(-) isolated from each process (Dowex and/or ABEC) was established by assaying for molybdate breakthrough, alumina levels and, in the case of the Dowex approach, residual organics. The separation processes are efficient (75% for Dowex, 90% for ABEC) and complete in less than 30 min. Overall, up to 2.1 GBq of (99m)Tc was produced using the (100)Mo(p,2n)(99m)Tc transformation, processed using the separation module and subjected to a detailed chemical and radionuclidic analysis. Due to its expense and limited availability, (100)MoO(4)(2-) was recovered in >90% yield using a precipitation/filtration/lyophilization approach. Na[(99m)Tc]TcO(4) was produced using a medical cyclotron, recovered using an automated purification module and found to exceed all established quality control parameters. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. The Spirit of Aggieland: Neoliberalism, Militarization, and Football Culture at Texas A&M University

    Science.gov (United States)

    Ternes, Neal

    2016-01-01

    Significant scholarship exists indicating an increase in militarization within the neoliberal university (see Armitage 2005; Giroux 2008; Giroux 2013), which has transformed the academic institution into "a factory that is engaged in the militarization of knowledge, namely, in the militarization of the facts, information and abilities…

  13. A LabVIEW based cyclotron magnetic field mapping system

    Energy Technology Data Exchange (ETDEWEB)

    Marti, F.; Johnson, P. [NSCL, Michigan State University, East Lansing, MI (United States)

    1999-07-01

    This paper describes the application of National Instruments LabVIEW to the NSCL K500 magnet mapping, as part of the Coupled Cyclotron Upgrade. LabVIEW provides a fast development environment for hardware control from a PC running Windows NT. The PC and LabVIEW environment allow non-professional computer programmers to obtain a reliable and flexible system where modifications can be quickly implemented. This program supports the use of motor controllers, data acquisition cards, digital I/O modules and GPIB instruments. A complete map of 360 degrees is obtained in approximately 90 minutes, measuring 185000 field values with a spacing of 1.6 mm in radius every degree. (author)

  14. Experimental measurement and Monte Carlo assessment of Argon-41 production in a PET cyclotron facility.

    Science.gov (United States)

    Infantino, Angelo; Valtieri, Lorenzo; Cicoria, Gianfranco; Pancaldi, Davide; Mostacci, Domiziano; Marengo, Mario

    2015-12-01

    In a medical cyclotron facility, (41)Ar (t1/2 = 109.34 m) is produced by the activation of air due to the neutron flux during irradiation, according to the (40)Ar(n,γ)(41)Ar reaction; this is particularly relevant in widely diffused high beam current cyclotrons for the production of PET radionuclides. While theoretical estimations of the (41)Ar production have been published, no data are available on direct experimental measurements for a biomedical cyclotron. In this work, we describe a sampling methodology and report the results of an extensive measurement campaign. Furthermore, the experimental results are compared with Monte Carlo simulations performed with the FLUKA code. To measure (41)Ar activity, air samples were taken inside the cyclotron bunker in sealed Marinelli beakers, during the routine production of (18)F with a 16.5 MeV GE-PETtrace cyclotron; this sampling thus reproduces a situation of absence of air changes. Samples analysis was performed in a gamma-ray spectrometry system equipped with HPGe detector. Monte Carlo assessment of the (41)Ar saturation yield was performed directly using the standard FLUKA score RESNUCLE, and off-line by the convolution of neutron fluence with cross section data. The average (41)Ar saturation yield per one liter of air of (41)Ar, measured in gamma-ray spectrometry, resulted to be 3.0 ± 0.6 Bq/µA*dm(3) while simulations gave a result of 6.9 ± 0.3 Bq/µA*dm(3) in the direct assessment and 6.92 ± 0.22 Bq/µA*dm(3) by the convolution neutron fluence-to-cross section. Copyright © 2015 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  15. Texas A&M University in the JET Collaboration - Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Fries, Rainer [Texas A & M Univ., College Station, TX (United States); Ko, Che-Ming [Texas A & M Univ., College Station, TX (United States)

    2016-05-02

    This final report summarizes the work done by PIs at Texas A&M University within the JET Topical Collaboration. The main focus of the group at Texas A&M has been the development and implementation of a hadronization model suitable to calculate hadronization of jet showers in heavy ion collisions event by event. The group successfully developed a hybrid model of parton recombination and remnant string fragmentation including recombination with thermal partons. A code realizing this model was developed and shared with other JET members. In addition, the group at Texas A&M worked on both open and hidden heavy flavor probes. In particular, they developed a description of heavy flavor hadronization based on recombination, and consistent with in-medium scattering rates of heavy quarks, and suggested the Ds meson as a precise probe of the hadronization mechanism. Another noteworthy focus of their work was electromagnetic probes, in particular, dileptons and photons from interactions of jets with the medium. In the soft sector the group has made several contributions to modern topics, e.g. the splitting of elliptic flow between isospin partners and the role of the initial strong gluon fields.

  16. Physiological studies of methane- and methanol-oxidizing bacteria: comparison of a primary alcohol dehydrogenase from Methylococcus capsulatus (Texas strain) and Pseudomonas species M27.

    Science.gov (United States)

    Patel, R N; Bose, H R; Mandy, W J; Hoare, D S

    1972-05-01

    A primary alcohol dehydrogenase has been purified from Methylococcus capsulatus (Texas strain). The purified enzyme catalyzes the oxidation of methanol and formaldehyde to formate; other primary alcohols are oxidized to their corresponding aldehydes. Ammonium ions are required for enzyme activity. The enzyme has a molecular weight of 120,000 daltons and consists of two 62,000 molecular-weight subunits which dissociate at acidic pH. The enzyme is similar to an alcohol dehydrogenase enzyme isolated from Pseudomonas sp. M27.

  17. Comparison of neutron fluxes in an 18-MeV unshielded cyclotron room and a 16.5-MeV self-shielded cyclotron room.

    Science.gov (United States)

    Fujibuchi, Toshioh; Horitsugi, Genki; Yamaguchi, Ichiro; Eto, Akihisa; Iwamoto, Yasuo; Obara, Satoshi; Iimori, Takashi; Masuda, Yoshitada; Watanabe, Hiroshi; Hatazawa, Jun

    2012-07-01

    Some medical compact cyclotrons have self-shielding to reduce neutron fluxes. Thermal neutron fluxes in an 18-MeV unshielded cyclotron room and in a 16.5-MeV self-shielded cyclotron room were evaluated. In addition, the radioactivities in concrete and metals due to thermal neutrons in the cyclotron rooms for 30 years were calculated of operation such that the sum of the ratio of the nuclide concentration to the nuclide clearance level was equal to 1. The thermal neutron flux from the unshielded cyclotron was approximately 10(2) cm(-2) s(-1), whereas that from the self-shielded cyclotron was approximately 10(2) cm(-2) s(-1). The thermal neutron fluxes for concrete, stainless steel, vessel steel, and aluminum that reached their clearance levels were 9.80 × 10(4), 2.17 × 10(3), 1.87 × 10(4), and 2.41 × 10(5) cm(-2) s(-1), respectively. The specific activities in the cyclotron room were found to be sufficiently below the clearance level when the self-shield was employed.

  18. Method and apparatus for ion cyclotron spectrometry

    Science.gov (United States)

    Dahl, David A [Idaho Falls, ID; Scott, Jill R [Idaho Falls, ID; McJunkin, Timothy R [Idaho Falls, ID

    2010-08-17

    An ion cyclotron spectrometer may include a vacuum chamber that extends at least along a z-axis and means for producing a magnetic field within the vacuum chamber so that a magnetic field vector is generally parallel to the z-axis. The ion cyclotron spectrometer may also include means for producing a trapping electric field within the vacuum chamber that includes at least a first section that induces a first magnetron effect that increases a cyclotron frequency of an ion and at least a second section that induces a second magnetron effect that decreases the cyclotron frequency of an ion. The cyclotron frequency changes induced by the first and second magnetron effects substantially cancel one another so that an ion traversing the at least first and second sections will experience no net change in cyclotron frequency.

  19. New radionuclides production on the isochronous cyclotron U-120M

    Energy Technology Data Exchange (ETDEWEB)

    Stursa, J.; Cihak, M.; Krivanek, M.; Kucera, J.; Lacman, J. [Nuclear Physics Institute, Prague (Czech Republic)

    1999-07-01

    The production of {sup 18}F for positron emission tomography (PET) applications and manufacturing of the {sup 81}Rb for the {sup 81}Rb/{sup 81m}Kr radionuclidic generator (used in lung ventilation studies) have been introduced as a new program of the twenty year old cyclotron U-120M(K=40, A/Z=1-2.8). The cyclotron conversion from positive to H/{sup -}D{sup -} accelerating regimes and the extraction by means of stripping were necessary for obtaining sufficiently high beam intensities. Two possible solutions of H{sup -} gain - either from the external high intensive (1 mA DC) old TRIUMF CUSP ion source or from the internal ion source with a cold cathode developed in our laboratory - are described. Axial injector characteristics for H{sup -} currents up to 1 mA together with optimizing the central region, the ion extraction system and upgrade of the vacuum system are presented. The realization of the enriched H{sub 2}O{sup 18} target, its setting into operation and the first results of {sup 18}F production (average yields {approx} 2 GBq/{mu}A. hour at EOB) are briefly discussed. (authors)

  20. Hydro-abrasive disintegration of alloy Monel K-500 – the influence of technological and abrasive factors on the surface quality

    Czech Academy of Sciences Publication Activity Database

    Cárach, J.; Hloch, Sergej; Hlaváček, Petr; Gombár, M.; Klichová, Dagmar; Botko, F.; Mital, D.; Lehocká, D.

    2016-01-01

    Roč. 149, č. 149 (2016), s. 17-23 E-ISSN 1877-7058. [International Conference on Manufacturing Engineering and Materials, ICMEM 2016. Nový Smokovec, 06.06.2016-10.06.2016] R&D Projects: GA MŠk ED2.1.00/03.0082; GA MŠk(CZ) LO1406 Institutional support: RVO:68145535 Keywords : hydroabrasive disintegration * Alloy Monel K-500 * rotating workpiece * roughness parameters * material removal rate Subject RIV: JQ - Machines ; Tools http://www.sciencedirect.com/science/article/pii/S1877705816311328

  1. Simulation, design, and testing of a high power collimator for the RDS-112 cyclotron.

    Science.gov (United States)

    Peeples, Johanna L; Stokely, Matthew H; Poorman, Michael C; Bida, Gerald T; Wieland, Bruce W

    2015-03-01

    A high power [F-18] fluoride target package for the RDS-112 cyclotron has been designed, tested, and commercially deployed. The upgrade includes the CF-1000 target, a 1.3kW water target with an established commercial history on RDS-111/Eclipse cyclotrons, and a redesigned collimator with improved heat rejection capabilities. Conjugate heat transfer analyses were employed to both evaluate the existing collimator capabilities and design a suitable high current replacement. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Radiation surveillance in and around cyclotron facility

    Science.gov (United States)

    Kaur, Amandeep; Sharma, Sarika; Mittal, BR

    2012-01-01

    The cyclotron is the most widely used particle accelerator for producing medically important radio nuclides. Many medical centers in India have installed compact medical cyclotrons for on-site production of short-lived positron-emitting radio nuclides such as 18F, 13N, and 11C. A mandatory requirement for cyclotron installation is radiation control permit from Atomic Energy Regulatory Board. Cyclotron radiation survey is an integral part of the overall radiation safety in the cyclotron facility. Radiation surveillance in and around a newly installed cyclotron was performed using ionization chamber counter and Geiger Muller counter before, during and after operating the cyclotron. The readings were recorded at various locations where a high radiation field was expected. The results were recorded, tabulated and analyzed. The highest exposure level (0.93 μSv) was found at the back wall of the radiochemistry lab facing the cyclotron vault. Reason for the high exposure of 0.93 μSv/h: Synthesis of 18F-Fluoro-Deoxy-Glucose (18F-FDG) was going in the synthesis module and activity (18F) was present in the synthesis module when reading was taken. All other values were found to be below the recommended levels of exposure. PMID:24019654

  3. Cyclotrons and positron emitting radiopharmaceuticals

    Energy Technology Data Exchange (ETDEWEB)

    Wolf, A.P.; Fowler, J.S.

    1984-01-01

    The state of the art of Positron Emission Tomography (PET) technology as related to cyclotron use and radiopharmaceutical production is reviewed. The paper discusses available small cyclotrons, the positron emitters which can be produced and the yields possible, target design, and radiopharmaceutical development and application. 97 refs., 12 tabs. (ACR)

  4. Ion source and injection line for high intensity medical cyclotron.

    Science.gov (United States)

    Jia, XianLu; Guan, Fengping; Yao, Hongjuan; Zhang, TianJue; Yang, Jianjun; Song, Guofang; Ge, Tao; Qin, Jiuchang

    2014-02-01

    A 14 MeV high intensity compact cyclotron, CYCIAE-14, was built at China Institute of Atomic Energy (CIAE). An injection system based on the external H- ion source was used on CYCIAE-14 so as to provide high intensity beam, while most positron emission tomography cyclotrons adopt internal ion source. A beam intensity of 100 μA/14 MeV was extracted from the cyclotron with a small multi-cusp H- ion source (CIAE-CH-I type) and a short injection line, which the H- ion source of 3 mA/25 keV H- beam with emittance of 0.3π mm mrad and the injection line of with only 1.2 m from the extraction of ion source to the medial plane of the cyclotron. To increase the extracted beam intensity of the cyclotron, a new ion source (CIAE-CH-II type) of 9.1 mA was used, with maximum of 500 μA was achieved from the cyclotron. The design and test results of the ion source and injection line optimized for high intensity acceleration will be given in this paper.

  5. 77 FR 39996 - Department of Mechanical Engineering, Texas A&M University, Notice of Decision on Application for...

    Science.gov (United States)

    2012-07-06

    ... International Trade Administration Department of Mechanical Engineering, Texas A&M University, Notice of...., Washington, D.C. Docket Number: 12-024. Applicant: Department of Mechanical Engineering, Texas A&M University..., 2012. Gregory W. Campbell, Director, Subsidies Enforcement Office, Import Administration. BILLING CODE...

  6. AUTOMATED FLOWCHART SYSTEM FROM TEXAS A&M UNIVERSITY

    Science.gov (United States)

    Woodford, W.

    1994-01-01

    An accurate flowchart is an important part of the documentation for any computer program. The flowchart offers the user an easy to follow overview of program operation and the maintenance programmer an effective debugging tool. The TAMU FLOWCHART System was developed to flowchart any program written in the FORTRAN language. It generates a line printer flowchart which is representative of the program logic. This flowchart provides the user with a detailed representation of the program action taken as each program statement is executed. The TAMU FLOWCHART System should prove to be a valuable aid to groups working with complex FORTRAN programs. Each statement in the program is displayed within a symbol which represents the program action during processing of the enclosed statement. Symbols available include: subroutine, function, and entry statements; arithmetic statements; input and output statements; arithmetical and logical IF statements; subroutine calls with or without argument list returns; computed and assigned GO TO statements; DO statements; STOP and RETURN statements; and CONTINUE and ASSIGN statements. Comment cards within the source program may be suppressed or displayed and associated with a succeeding source statement. Each symbol is annotated with a label (if present in the source code), a block number, and the statement sequence number. Program flow and options within the program are represented by line segments and direction indicators connecting symbols. The TAMU FLOWCHART System should be able to accurately flowchart any working FORTRAN program. This program is written in COBOL for batch execution and has been implemented on an IBM 370 series computer with an OS operating system and with a central memory requirement of approximately 380K of 8 bit bytes. The TAMU FLOWCHART System was developed in 1977.

  7. Nuclear safety analyses and core design calculations to convert the Texas A & M University Nuclear Science Center reactor to low enrichment uranium fuel. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Parish, T.A.

    1995-03-02

    This project involved performing the nuclear design and safety analyses needed to modify the license issued by the Nuclear Regulatory Commission to allow operation of the Texas A& M University Nuclear Science Center Reactor (NSCR) with a core containing low enrichment uranium (LEU) fuel. The specific type of LEU fuel to be considered was the TRIGA 20-20 fuel produced by General Atomic. Computer codes for the neutronic analyses were provided by Argonne National Laboratory (ANL) and the assistance of William Woodruff of ANL in helping the NSCR staff to learn the proper use of the codes is gratefully acknowledged. The codes applied in the LEU analyses were WIMSd4/m, DIF3D, NCTRIGA and PARET. These codes allowed full three dimensional, temperature and burnup dependent calculations modelling the NSCR core to be performed for the first time. In addition, temperature coefficients of reactivity and pulsing calculations were carried out in-house, whereas in the past this modelling had been performed at General Atomic. In order to benchmark the newly acquired codes, modelling of the current NSCR core with highly enriched uranium fuel was also carried out. Calculated results were compared to both earlier licensing calculations and experimental data and the new methods were found to achieve excellent agreement with both. Therefore, even if an LEU core is never loaded at the NSCR, this project has resulted in a significant improvement in the nuclear safety analysis capabilities established and maintained at the NSCR.

  8. A cyclotron isotope production facility designed to maximize production and minimize radiation dose

    Science.gov (United States)

    Dickie, W. J.; Stevenson, N. R.; Szlavik, F. F.

    1993-06-01

    Continuing increases in requirements from the nuclear medicine industry for cyclotron isotopes is increasing the demands being put on an aging stock of machines. In addition, with the 1990 recommendations of the ICRP publication in place, strict dose limits will be required and this will have an effect on the way these machines are being operated. Recent advances in cyclotron design combined with lessons learned from two decades of commercial production mean that new facilities can result in a substantial charge on target, low personnel dose, and minimal residual activation. An optimal facility would utilize a well engineered variable energy/high current H - cyclotron design, multiple beam extraction, and individual target caves. Materials would be selected to minimize activation and absorb neutrons. Equipment would be designed to minimize maintenance activities performed in high radiation fields.

  9. Oceanography and Geoscience Scholars at Texas A&M University Funded through the NSF S-STEM (Scholarships in Science, Technology, Engineering and Mathematics) Program

    Science.gov (United States)

    Richardson, M. J.; Gardner, W. D.

    2016-02-01

    Over the last seven years we have led the creation and implementation of the Oceanography and Geoscience Scholars programs at Texas A&M University. Through these programs we have been able to provide scholarship support for 92 undergraduates in Geosciences and 29 graduate students in Oceanography. Fifty-seven undergraduate scholars have graduated in Geosciences: 30 undergraduate students in Meteorology, 7 in Geology, and 20 in Environmental Geosciences. Two students have graduated in other STEM disciplines. Twenty-four students are in the process of completing their undergraduate degrees in STEM disciplines. Twenty-three students have graduated with MS or PhD degrees in Oceanography and five PhD students are completing their dissertations. As specified in the program solicitation all of the scholars are academically talented students with demonstrated financial need as defined by the FAFSA (Free Application for Federal Student Aid). We have endeavored to recruit students from underrepresented groups. One-third of the undergraduate scholars were from underrepresented groups; 28% of the graduate students. We will present the challenges and successes of these programs.

  10. Comprehensive UAV agricultural remote-sensing research at Texas A M University

    Science.gov (United States)

    Thomasson, J. Alex; Shi, Yeyin; Olsenholler, Jeffrey; Valasek, John; Murray, Seth C.; Bishop, Michael P.

    2016-05-01

    Unmanned aerial vehicles (UAVs) have advantages over manned vehicles for agricultural remote sensing. Flying UAVs is less expensive, is more flexible in scheduling, enables lower altitudes, uses lower speeds, and provides better spatial resolution for imaging. The main disadvantage is that, at lower altitudes and speeds, only small areas can be imaged. However, on large farms with contiguous fields, high-quality images can be collected regularly by using UAVs with appropriate sensing technologies that enable high-quality image mosaics to be created with sufficient metadata and ground-control points. In the United States, rules governing the use of aircraft are promulgated and enforced by the Federal Aviation Administration (FAA), and rules governing UAVs are currently in flux. Operators must apply for appropriate permissions to fly UAVs. In the summer of 2015 Texas A&M University's agricultural research agency, Texas A&M AgriLife Research, embarked on a comprehensive program of remote sensing with UAVs at its 568-ha Brazos Bottom Research Farm. This farm is made up of numerous fields where various crops are grown in plots or complete fields. The crops include cotton, corn, sorghum, and wheat. After gaining FAA permission to fly at the farm, the research team used multiple fixed-wing and rotary-wing UAVs along with various sensors to collect images over all parts of the farm at least once per week. This article reports on details of flight operations and sensing and analysis protocols, and it includes some lessons learned in the process of developing a UAV remote-sensing effort of this sort.

  11. Method and apparatuses for ion cyclotron spectrometry

    Science.gov (United States)

    Dahl, David A [Idaho Falls, ID; Scott, Jill R [Idaho Falls, ID; McJunkin, Timothy R [Idaho Falls, ID

    2012-03-06

    An ion cyclotron spectrometer may include a vacuum chamber that extends at least along a z-axis and means for producing a magnetic field within the vacuum chamber so that a magnetic field vector is generally parallel to the z-axis. The ion cyclotron spectrometer may also include means for producing a trapping electric field within the vacuum chamber. The trapping electric field may comprise a field potential that, when taken in cross-section along the z-axis, includes at least one section that is concave down and at least one section that is concave up so that ions traversing the field potential experience a net magnetron effect on a cyclotron frequency of the ions that is substantially equal to zero. Other apparatuses and a method for performing ion cyclotron spectrometry are also disclosed herein.

  12. The 88-Inch Cyclotron: A One-Stop Facility for Electronics Radiation and Detector Testing

    Energy Technology Data Exchange (ETDEWEB)

    Kireeff Covo, M.; Albright, R. A.; Ninemire, B. F.; Johnson, M. B.; Hodgkinson, A.; Loew, T.; Benitez, J. Y.; Todd, D. S.; Xie, D. Z.; Perry, T.; Phair, L.; Bernsteiny, L. A.; Bevins, J.; Brown, J. A.; Goldblum, B. L.; Harasty, M.; Harrig, K. P.; Laplace, T. A.; Matthews, E. F.; Bushmaker, A.; Walker, D.; Oklejas, V.; Hopkins, A. R.; Bleuel, D. L.; Chen, J.; Cronin, S. B.

    2017-10-01

    In outer space down to the altitudes routinely flown by larger aircrafts, radiation can pose serious issues for microelectronics circuits. The 88-Inch Cyclotron at Lawrence Berkeley National Laboratory is a sector-focused cyclotron and home of the Berkeley Accelerator Space Effects Facility, where the effects of energetic particles on sensitive microelectronics are studied with the goal of designing electronic systems for the space community. This paper describes the flexibility of the facility and its capabilities for testing the bombardment of electronics by heavy ions, light ions, and neutrons. Experimental capabilities for the generation of neutron beams from deuteron breakups and radiation testing of carbon nanotube field effect transistor will be discussed.

  13. Cyclotron Phase-Coherent Ion Spatial Dispersion in a Non-Quadratic Trapping Potential is Responsible for FT-ICR MS at the Cyclotron Frequency

    Science.gov (United States)

    Nagornov, Konstantin O.; Kozhinov, Anton N.; Tsybin, Yury O.

    2017-11-01

    Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) at the cyclotron frequency instead of the reduced cyclotron frequency has been experimentally demonstrated using narrow aperture detection electrode (NADEL) ICR cells. Here, based on the results of SIMION simulations, we provide the initial mechanistic insights into the cyclotron frequency regime generation in FT-ICR MS. The reason for cyclotron frequency regime is found to be a new type of a collective motion of ions with a certain dispersion in the initial characteristics, such as pre-excitation ion velocities, in a highly non-quadratic trapping potential as realized in NADEL ICR cells. During ion detection, ions of the same m/z move in phase for cyclotron ion motion but out of phase for magnetron (drift) ion motion destroying signals at the fundamental and high order harmonics that comprise reduced cyclotron frequency components. After an initial magnetron motion period, ion clouds distribute into a novel type of structures - ion slabs, elliptical cylinders, or star-like structures. These structures rotate at the Larmor (half-cyclotron) frequency on a plane orthogonal to the magnetic field, inducing signals at the true cyclotron frequency on each of the narrow aperture detection electrodes. To eliminate the reduced cyclotron frequency peak upon dipolar ion detection, a number of slabs or elliptical cylinders organizing a star-like configuration are formed. In a NADEL ICR cell with quadrupolar ion detection, a single slab or an elliptical cylinder is sufficient to minimize the intensity of the reduced cyclotron frequency components, particularly the second harmonic. [Figure not available: see fulltext.

  14. Study of the Polarization Strategy for Electron Cyclotron Heating Systems on HL-2M

    Science.gov (United States)

    Zhang, F.; Huang, M.; Xia, D. H.; Song, S. D.; Wang, J. Q.; Huang, B.; Wang, H.

    2016-06-01

    As important components integrated in transmission lines of electron cyclotron heating systems, polarizers are mainly used to obtain the desired polarization for highly efficient coupling between electron cyclotron waves and plasma. The polarization strategy for 105-GHz electron cyclotron heating systems of HL-2M tokamak is studied in this paper. Considering the polarizers need high efficiency, stability, and low loss to realize any polarization states, two sinusoidal-grooved polarizers, which include a linear polarizer and an elliptical polarizer, are designed with the coordinate transformation method. The parameters, the period p and the depth d, of two sinusoidal-grooved polarizers are optimized by a phase difference analysis method to achieve an almost arbitrary polarization. Finally, the optimized polarizers are manufactured and their polarization characteristics are tested with a low-power test platform. The experimental results agree well with the numerical calculations, indicating that the designed polarizers can meet the polarization requirements of the electron cyclotron heating systems of HL-2M tokamak.

  15. EC-5 fifth international workshop on electron cyclotron emission and electron cyclotron heating

    Energy Technology Data Exchange (ETDEWEB)

    Prater, R.; Lohr, J. [eds.

    1985-12-31

    This report contains papers on the following topics: electron cyclotron emission measurements; electron cyclotron emission theory; electron cyclotron heating; gyrotron development; and ECH systems and waveguide development. These paper have been indexed separately elsewhere. (LSP).

  16. Vacuum Control Systems of the Cyclotrons in VECC, Kolkata

    Science.gov (United States)

    Roy, Anindya; Akhtar, Javed; Yadav, R. C.; Bhole, R. B.; Pal, Sarbajit; Sarkar, D.; Bhandari, R. K.

    2012-11-01

    VECC has undertaken the modernization of the K-130 Room Temperature Cyclotron (RTC) (operational since 1978) and commissioning of K-500 Superconducting Cyclotron (SCC) at present. The control system of RTC vacuum system has been upgraded to Programmable Logic Controller (PLC) based automated system from relay based manual system. A distributed PLC based system is under installation for SCC vacuum system. The requirement of high vacuum in both the cyclotrons (1×10-6 mbar for RTC and 5 × 10-8 mbar SCC) imposes the reliable local and remote operation of all vacuum components and instrumentation. The design and development of the vacuum control system of two cyclotrons using the Experimental Physics and Industrial Control System (EPICS) distributed real-time software tools are presented.

  17. EBCO Technologies TR Cyclotrons, Dynamics, Equipment, and Applications

    Science.gov (United States)

    Johnson, R. R.; Erdman, K. L.; Gyles, Wm.; Burbee, J.; VanLier, E.; Kovacs, M.; Perron, F.

    2003-08-01

    The Ebco Technologies TR cyclotrons have a common parent in the 500 MeV negative ion cyclotron at TRIUMF in Vancouver. As such, the TR cyclotrons have features that can be adapted for specific application. The cyclotron design is modularized into ion source and injection system, central region and then extraction. The cyclotron ion source is configured for cyclotron beam currents ranging from 50 microAmps to 2 milliAmps. The injection line can be operated in either continuous (CW) or in pulsed mode. The center region of the cyclotron is configured to match the ion source configuration. The extracted beams are directed either to a local target station or to beam lines and thence to target stations. There has been development both in solid, liquid and gas targets. There has been development in radioisotope handling techniques, target material recovery and radiochemical synthesis.

  18. MEGHNAD–A multi element detector array for heavy ion collision ...

    Indian Academy of Sciences (India)

    2015-11-27

    Nov 27, 2015 ... In the coming decade, the expanding field of experimental nuclear physics in our country is going to see a quantum leap in research and developmental activities with new accelerator facilities like the variable energy cyclotron with ECR heavy ion source, the upcoming K-500 superconducting cyclotron, ...

  19. Ion cyclotron waves at unmagnetized bodies: a comparison of Mars, Venus and Titan

    Science.gov (United States)

    Wei, H.; Russell, C. T.; Cowee, M.; Blanco-Cano, X.; Zhang, T.; Dougherty, M. K.

    2009-12-01

    Mars, Venus and Titan do not have appreciable global magnetic fields. Their high-altitude neutral atmospheres are not shielded from being lost to the solar wind and the Saturnian magnetosphere. When the atmospheric hydrogen atoms of Mars and Venus are ionized and picked up by the solar wind, proton cyclotron waves are created from the free energy of the ring-beam distribution of the pick-up ions. At Mars, proton cyclotron waves observed by Mars Global Surveyor extend from the magnetosheath to over 12 Mars radii, with intermittent occurrence and amplitudes slowly varying with distance. The wave occurrence pattern indicates a disk-shaped hydrogen exosphere of Mars with asymmetry in the direction of the interplanetary electric field. Fast neutrals produced by neutralization of the pickup ions can travel across fieldlines to distant regions where they get re-ionized and produce waves far downstream. Thus the top of Mars exosphere extends in a disk to high altitude, with its orientation controlled by the interplanetary magnetic field. At Venus, plasma waves having properties similar to ion cyclotron waves are observed in the solar wind around the planet by Venus Express, with wave frequencies that range from 0.2 to 5.9 times of the proton gyrofrequency. Statistical study shows that the waves with frequency higher than 1.5 times the proton gyrofrequency are not generated locally and are similar to the waves observed at 0.3 AU and 1 AU which appear to be created near the Sun and convected outward with the solar wind. The rest of the waves are mostly magnetically connected to the bow shock, so they are probably generated by particles backstreaming from the shock and propagate out further from the foreshock. At Titan, ion cyclotron waves are not observed although wave generation is expected due to the large pickup rate of hydrocarbon ions at high altitude of Titan. We attempt to understand the lack of ion cyclotron waves at Titan using hybrid simulations. Studying and

  20. SPES: A new cyclotron-based facility for research and applications with high-intensity beams

    Science.gov (United States)

    Maggiore, M.; Campo, D.; Antonini, P.; Lombardi, A.; Manzolaro, M.; Andrighetto, A.; Monetti, A.; Scarpa, D.; Esposito, J.; Silvestrin, L.

    2017-06-01

    In 2016, Laboratori Nazionali di Legnaro (Italy) started the commissioning of a new accelerator facility based on a high-power cyclotron able to deliver proton beams up to 70 MeV of energy and 700 μA current. Such a machine is the core of the Selective Production of Exotic Species (SPES) project whose main goal is to provide exotics beam for nuclear and astrophysics research and to deliver high-intensity proton beams for medical applications and neutrons generator.

  1. Recent achievements in Tc-99m radiopharmaceutical direct production by medical cyclotrons.

    Science.gov (United States)

    Boschi, Alessandra; Martini, Petra; Pasquali, Micol; Uccelli, Licia

    2017-09-01

    99mTc is the most commonly used radionuclide in the field of diagnostic imaging, a noninvasive method intended to diagnose a disease, assess the disease state and monitor the effects of treatments. Annually, the use of 99mTc, covers about 85% of nuclear medicine applications. This isotope releases gamma rays at about the same wavelength as conventional X-ray diagnostic equipment, and owing to its short half-life (t½ = 6 h) is ideal for diagnostic nuclear imaging. A patient can be injected with a small amount of 99mTc and within 24 h almost 94% of the injected radionuclide would have decayed and left the body, limiting the patient's radiation exposure. 99mTc is usually supplied to hospitals through a 99Mo/99mTc radionuclide generator system where it is produced from the β decay of the parent nuclide 99Mo (t½ = 66 h), which is produced in nuclear reactors via neutron fission. Recently, the interruption of the global supply chain of reactor-produced 99Mo, has forced the scientific community to investigate alternative production routes for 99mTc. One solution was to consider cyclotron-based methods as potential replacement of reactor-based technology and the nuclear reaction 100Mo(p,2n)99mTc emerged as the most worthwhile approach. This review reports some achievements about 99mTc produced by medical cyclotrons. In particular, the available technologies for target design, the most efficient extraction and separation procedure developed for the purification of 99mTc from the irradiated targets, the preparation of high purity 99mTc radiopharmaceuticals and the first clinical studies carried out with cyclotron produced 99mTc are described.

  2. A simple and powerful XY-Type current monitor for 30 MeV IPEN/CNEN-SP cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Barcellos, Henrique; Matsuda, Hylton; Sumyia, Luiz Carlos do A.; Junqueira, Fernando de C.; Costa, Osvaldo L. da, E-mail: hbolivei@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2017-11-01

    A water-cooled XY-type current monitor was designed and built in the Cyclotrons Laboratory of the Nuclear and Energy Research Institute (IPEN). It is a very simple design and easily adaptable to the cyclotron beam lines. Tests were done demonstrating to be an instrument of great assistance in proton beam position along beam transport line and target port. Nowadays the XY-type current monitor has been widely used in {sup 18}F-FDG routine productions, employing irradiation system which were originally designed for productions on 18 MeV cyclotron accelerator only, however, applying the XY-type current monitor the target port may be exchanged between the 30 MeV and 18 MeV cyclotrons and the observed results are in perfect agreement with expected. (author)

  3. The ion cyclotron turbulence generated by a low frequency kinetic Alfvén wave and turbulent heating of ions

    Science.gov (United States)

    Mikhailenko, V. S.; Mikhailenko, V. V.; Lee, Hae June

    2018-01-01

    The ion cyclotron instability driven by a strong kinetic Alfvén wave is investigated as a possible source of anisotropic heating of ions in the sun's corona. We present a novel model of a plasma with coupled inhomogeneous current and shearing flow, which results from the particle's motion in the electric field of the kinetic Alfvén wave of finite wavelength. The investigation is performed employing the non-modal kinetic theory grounded on the shearing mode approach. The solution of the governing linear integral equation for the perturbed potential displays that the flow velocity shear, which for the corona conditions may be above the growth rate of the ion cyclotron instability in the plasma with steady current, changes the exponential growth of the ion cyclotron potential on the power function of time, that impedes the growth of the unstable ion cyclotron wave and reduces the turbulent heating rate of ions across the magnetic field.

  4. Opening a Can of wERMS: Texas A&M University's Experiences in Implementing Two Electronic Resource Management Systems

    Science.gov (United States)

    Hartnett, Eric; Price, Apryl; Smith, Jane; Barrett, Michael

    2010-01-01

    Over the past few years, Texas A&M University (TAMU) has searched for a way to administer its electronic subscriptions as well as the electronic subscriptions shared among the TAMU System. In this article, we address our attempts to implement an effective electronic resource management system (ERMS), both for subscriptions on the main campus…

  5. Genetic evidence of enzootic leishmaniasis in a stray canine and Texas mouse from sites in west and central Texas

    Directory of Open Access Journals (Sweden)

    Evan J Kipp

    Full Text Available We detected Leishmania mexicana in skin biopsies taken from a stray canine (Canis familiaris and Texas mouse (Peromyscus attwateri at two ecologically disparate sites in west and central Texas using polymerase chain reaction (PCR. A single PCR-positive dog was identified from a sample of 96 stray canines and was collected in a peri-urban area in El Paso County, Texas. The PCR-positive P. attwateri was trapped at a wildlife reserve in Mason County, Texas, from a convenience sample of 20 sylvatic mammals of different species. To our knowledge, this represents the first description of L. mexicana in west Texas and extends the known geographic range of the parasite to an area that includes the arid Chihuahuan Desert. Our finding of L. mexicana in P. attwateri represents a new host record and is the first description of the parasite in a wild peromyscid rodent in the United States.

  6. Genetic evidence of enzootic leishmaniasis in a stray canine and Texas mouse from sites in west and central Texas.

    Science.gov (United States)

    Kipp, Evan J; Mariscal, Jacqueline; Armijos, Rodrigo X; Weigel, Margaret; Waldrup, Kenneth

    2016-10-01

    We detected Leishmania mexicana in skin biopsies taken from a stray canine (Canis familiaris) and Texas mouse (Peromyscus attwateri) at two ecologically disparate sites in west and central Texas using polymerase chain reaction (PCR). A single PCR-positive dog was identified from a sample of 96 stray canines and was collected in a peri-urban area in El Paso County, Texas. The PCR-positive P. attwateri was trapped at a wildlife reserve in Mason County, Texas, from a convenience sample of 20 sylvatic mammals of different species. To our knowledge, this represents the first description of L. mexicana in west Texas and extends the known geographic range of the parasite to an area that includes the arid Chihuahuan Desert. Our finding of L. mexicana in P. attwateri represents a new host record and is the first description of the parasite in a wild peromyscid rodent in the United States.

  7. Factors influencing the choice of a career in food-animal practice among recent graduates and current students of Texas A&M University, College of Veterinary Medicine.

    Science.gov (United States)

    Lenarduzzi, Roland; Sheppard, Guy A; Slater, Margaret R

    2009-01-01

    Concerns about a shortage of large and mixed-animal veterinarians have been discussed in the profession. To better understand veterinary career choices among currently enrolled veterinary students (classes of 2007-2010) and recent graduate veterinarians in Texas (classes of 2002-2006), an online survey was developed. The objectives were to examine: (1) the respondents' backgrounds, demographic data, and experiences; (2) the respondents' working conditions and rural lifestyle considerations; (3) the respondents' perceptions of large/mixed-animal practice; and (4) the factors that have influenced respondents' career choices. The response rate was 37% (390/1,042). Overall, 72% of students and 55% of recent graduates were interested in large/mixed-animal practice. More than 70% of respondents indicated that veterinary practitioners had the strongest personal influence on career choices. Respondents who were no longer interested in large/mixed-animal practice, or who had never been interested, reported no experience with large animals (42% and 64%, respectively) as the most common reason for their lack of interest. Previous and current interest in large/mixed-animal practice were associated with working in a large/mixed-animal practice, any agricultural experience, and working for at least 6 months on a farm or ranch. Any 4-H experience increased the likelihood of previous interest, while being married decreased the likelihood of current interest. Student contact with practitioners (82%) and financial considerations (77%) were most commonly cited as factors that would make a career in large/mixed-animal practice more attractive. Rural lifestyle drawbacks influenced respondents' career choices. Many forms of agricultural experience may expose and encourage students to consider large/mixed-animal practice.

  8. Texas M-E flexible pavement design system: literature review and proposed framework.

    Science.gov (United States)

    2012-04-01

    Recent developments over last several decades have offered an opportunity for more rational and rigorous pavement design procedures. Substantial work has already been completed in Texas, nationally, and internationally, in all aspects of modeling, ma...

  9. Reflection and backscattering of microwaves under doubling of the plasma density and displacement of the gyroresonance region during electron cyclotron resonance heating of plasma in the l-2M stellarator

    Energy Technology Data Exchange (ETDEWEB)

    Batanov, G. M.; Borzosekov, V. D.; Vasilkov, D. G.; Kolik, L. V.; Konchekov, E. M., E-mail: konchekov@fpl.gpi.ru; Malakhov, D. V.; Vafin, I. Yu.; Petrov, A. E.; Sarksyan, K. A.; Sakharov, A. S.; Stepakhin, V. D.; Kharchev, N. K. [Russian Academy of Sciences, Prokhorov General Physics Institute (Russian Federation)

    2016-08-15

    Reflection and backscattering of high-power (400 kW) gyrotron radiation creating and heating plasma at the second harmonic of the electronic cyclotron frequency in the L-2M stellarator have been investigated experimentally. The effect of the displacement of the gyroresonance region from the axis of the plasma column under doubling of the plasma density on the processes of reflection and backscattering of microwave radiation has been examined. A near doubling of short-wavelength (k{sub ⊥} ≈ 30 cm{sup –1}) turbulent density fluctuations squared is observed. The change in the energy confinement time under variations of plasma parameters and characteristics of short-wavelength turbulence is discussed. A discrepancy between the measured values of the reflection coefficient from the electron cyclotron resonance heating region and predictions of the one-dimensional model is revealed.

  10. A gain and bandwidth enhanced transimpedance preamplifier for Fourier-transform ion cyclotron resonance mass spectrometry

    Science.gov (United States)

    Lin, Tzu-Yung; Green, Roger J.; O'Connor, Peter B.

    2011-01-01

    The nature of the ion signal from a 12-T Fourier-transform ion cyclotron resonance mass spectrometer and the electronic noise were studied to further understand the electronic detection limit. At minimal cost, a new transimpedance preamplifier was designed, computer simulated, built, and tested. The preamplifier design pushes the electronic signal-to-noise performance at room temperature to the limit, because of its enhanced tolerance of the capacitance of the detection device, lower intrinsic noise, and larger flat mid-band gain (input current noise spectral density of around 1 pA/\\documentclass[12pt]{minimal}\\begin{document}$\\sqrt{\\mbox{Hz}}$\\end{document}Hz when the transimpedance is about 85 dBΩ). The designed preamplifier has a bandwidth of ∼3 kHz to 10 MHz, which corresponds to the mass-to-charge ratio, m/z, of approximately 18 to 61 k at 12 T. The transimpedance and the bandwidth can be easily adjusted by changing the value of passive components. The feedback limitation of the circuit is discussed. With the maximum possible transimpedance of 5.3 MΩ when using an 0402 surface mount resistor, the preamplifier was estimated to be able to detect ∼110 charges in a single scan. PMID:22225232

  11. A new way to measure the electron cyclotron frequency

    Science.gov (United States)

    Palmer, F. L.

    1993-03-01

    A method is described for using spin flips to measure the 0 to 1 cyclotron transition frequency of a single electron in a Penning trap. Detection can be accomplished with magnetic bottles of 10 T/m2 or less, thereby greatly reducing the thermal broadening of the cyclotron line. This method complements a recently published technique for measuring the anomaly frequency, making a more precise measurement of the electron anomaly ratio possible.

  12. SC Cyclotron and RIB Facilities in Kolkata

    CERN Document Server

    Sinha, Bikash; Chakrabarti, Alok

    2005-01-01

    The superconducting cyclotron under construction at this Centre has bending limit (K-bend) of 520 and focusing limit (K-foc) of 160. It is being constructed, primarily, for nuclear physics experiments with heavy ion beams at intermediate energies. The 100-ton main magnet is currently in the commissioning phase with the main coil already at 4.2K temperature. Magnetic field measurements will be carried out over the next several months. All other systems of the cyclotron are in an advanced stage of fabrication or development. We plan to start assembly of the complete cyclotron around the end of 2005. In the phase-I of the project one beam line has been provided. Construction of three more beam lines and various experimental facilities for nuclear physics as well as irradiation experiments has also been funded and the work is well on its way. An ISOL type Radioactive Ion Beam (RIB) facility is being built with the existing K=130 room temperature cyclotron, VEC, as the primary beam source. In-beam RIB production a...

  13. Physical trajectory profile data from glider Stommel deployed by Texas A&M University; Texas A&M University - College Station; Geochemical and Environmental Research Group in the Gulf of Mexico from 2017-01-20 to 2017-05-07 (NCEI Accession 0162538)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Monitoring the baseline water quality across the Texas shelf. The National Centers for Environmental Information (NCEI) received the data in this archival package...

  14. Physical trajectory profile data from glider Stommel deployed by Texas A&M University; Texas A&M University - College Station; Geochemical and Environmental Research Group in the Gulf of Mexico from 2017-06-27 to 2017-07-05 (NCEI Accession 0164085)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Monitoring the baseline water quality across the Texas shelf. The National Centers for Environmental Information (NCEI) received the data in this archival package...

  15. Filling and Recycling Apparatus of a Cyclotron Target with Enriched Krypton for Production of Radiopharmaceuticals

    Directory of Open Access Journals (Sweden)

    M. Vognar

    2001-01-01

    Full Text Available An apparatus for multiple filling of a cyclotron target with enriched Kr gas is described. The system is based on recycling pressurized gas by cryogenic pumping between the target tube and storage containers. The design and construction makes use of previous experience in the construction and operation of two analogue apparatuses for Xe124 high pressure gas targets, but major modifications have been incorporated, evoked by the different physical properties of Kr, by the character of the nuclear reaction, and by the demand for automation from the side of the end user.

  16. Operation of a quasioptical electron cyclotron maser

    Energy Technology Data Exchange (ETDEWEB)

    Morse, E.C.; Pyle, R.V.

    1984-12-01

    The electron cyclotron maser or gyrotron concept has been developed to produce sources producing 200 kW at 28 GHz continuously, and higher power outputs and frequencies in pulsed mode. These sources have been useful in electron cyclotron resonance heating (ECRH) in magnetically confined fusion devices. However, higher frequencies and higher power levels will be required in reactor-grade fusion plasmas, with likely requirements of 1.0 MW or more per source at 140 GHz. Conventional gyrotrons follow a trend of decreasing power for increasing frequency. In order to circumvent this problem, the quasioptical electron cyclotron maser was proposed. In this device, the closed resonator of the conventional gyrotron is replaced with an open, Fabry-Perot type resonator. The cavity modes are then the TEM-type modes of an optical laser. The advantage of this configuration is that the cavity size is not a function of frequency, since the length can be any half-integer number of wavelengths. Furthermore, the beam traverses across the cavity transverse to the direction of radiation output, and thus the rf window design is less complicated than in conventional tubes. The rf output, if obtained by diffraction coupling around one of the mirrors, could be in a TEM mode, which would allow for quasioptical transmission of the microwaves into the plasma in fusion devices. 4 references, 1 figure.

  17. The Effect of Microstructural Variation on the Hydrogen Environment-Assisted Cracking of Monel K-500

    Science.gov (United States)

    Harris, Zachary D.; Dolph, Justin D.; Pioszak, Greger L.; Rincon Troconis, Brendy C.; Scully, John R.; Burns, James T.

    2016-07-01

    The influence of microstructural variation on hydrogen environment-assisted cracking (HEAC) of Monel K-500 was evaluated using five nominally peak-aged lots of material tested under slow-rising stress intensity loading while immersed in NaCl solution under cathodic polarizations. Minimal variation in HEAC resistance among material lots was observed for an applied potential of -950 mVSCE ( E app, vs saturated calomel), whereas lot-to-lot variability in the fracture morphology demonstrates a significant difference in the HEAC resistance at the less negative potential of -850 mVSCE, suggesting that relatively severe H environments produce sufficient crack-tip H to minimize the impact of metallurgical differences. Sensitivity analyses accomplished by varying the inputs used in decohesion-based, micromechanical models imply significant variations in HEAC resistance are possible for realistic changes in grain boundary toughness, hydrogen uptake behavior, and yield strength. Grain size, impurity segregation (including the effects of gettering elements), grain boundary character/connectivity, and crack path tortuosity are also considered in the context of HEAC susceptibility. Yield strength, global hydrogen content, as well as impurity segregation to grain boundaries, especially boron and sulfur, are speculatively considered to be the dominant contributions in determining HEAC resistance. Modifications that would incorporate the effects of grain boundary segregation are proposed for the K TH model; detailed validation of such changes require high-fidelity and quantitative inputs for the degree of grain boundary segregation. Regardless, fracture mechanics-based HEAC results, detailed microstructural characterization, and micromechanical modeling were successfully coupled to gain insights into the influences governing the microstructure-dependent HEAC susceptibility of Monel K-500.

  18. Cyclotron Production of (99m)Tc using (100)Mo2C targets.

    Science.gov (United States)

    Richards, Vernal N; Mebrahtu, Efrem; Lapi, Suzanne E

    2013-10-01

    An investigative study of the (100)Mo (p,2n)(99m)Tc reaction on a medical cyclotron using (100)Mo2C is reported. This is the first report of this compound being used as a target for this reaction. (100)Mo2C, a refractory carbide with high thermal conductivity, properties which underscore its use on a cyclotron, was synthesized using (100)MoO3. Its ease of oxidation back to (100)MoO3 under air at elevated temperatures facilitates the use of thermo-chromatography, a high temperature gas phase separation technique for the separation and isolation of (99m)Tc. Activity yields for (99m)Tc averaged 84% of the calculated theoretical yields. Additionally, the percent recovery of MoO3, the precursor for Mo2C, was consistently high at 85% ensuring a good life cycle for this target material. The produced (99m)Tc was radio-chemically pure and easily labeled MDP for imaging purposes. © 2013.

  19. Trapping, detection, and mass measurement of individual ions in a Fourier transform ion cyclotron resonance mass spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Bruce, J.E.; Cheng, X.; Bakhtiar, R.; Wu, Q.; Hofstadler, S.A.; Anderson, G.A.; Smith, R.D. [Pacific Northwest Lab., Richland, WA (United States)

    1994-08-24

    A fourier transform ion cyclotron resonance (FTICR) mass spectrometer has been used to trap individual multiply charged ions of several high molecular weight polymers, including poly(ethylene oxide), sodium poly(styrene sulfonate), and the protein bovine serum albumin. Detection of these ions is performed with the nondestructive method distinctive of FTICR, which also allows remeasurement of the same ion or ion population over several hours. For the determination of the charge states (and hence the masses) of individual ions, a new scheme was developed on the basis of the observation of the stepwise m/z shifts that results from charge exchange reactions or adduction of a substance of known mass. A novel technique for mass determination of individual ions has been made possible with the observation of cyclotron frequency shifts during the time-domain acquisition period. This time-resolved ion correlation (TRIC) technique allows reactant and product ions to be correlated with confidence and provides the basis for simultaneously studying a moderate number of ions. In this work, a range of observations related to the detection and measurement of individual ions is presented, as are examples of mass determinations of individual ions performed by utilizing the TRIC technique. 47 refs., 9 figs., 2 tabs.

  20. Quench analysis of a novel compact superconducting cyclotron

    Science.gov (United States)

    Ghosh, Sundeep; Dutta Gupta, Anjan; Kanti Dey, Malay; Pal, Gautam

    2017-02-01

    Design and analysis of a compact superconducting cyclotron dedicated for medical applications in the fields of nuclear medicine and therapy is presently being pursued in our organization. The novelty of this cyclotron lies in the fact that it does not consist of any iron-pole. The cyclotron magnet will be made of a set of NbTi coils comprising of solenoid and sector coils which are housed in two halves on either sides of the median plane. The average magnetic field is 1.74 T and the maximum extraction energy is 25 MeV, which is sufficient for production of 99mTc from Mo. In this paper, quench analyses of the coils have been discussed in details considering adiabatic condition. The entire cryostat magnet along with coils, formers and support links were modelled for the quench simulation. Self and mutual inductances of all the coils were obtained from a separate magnetic analysis and used in the simulation. Parametric analyses were carried out with different quench initiation energy at various critical locations on the coil surface. The corresponding quench behaviour, i.e. maximum temperature rise, maximum voltage and current decay in each of the coils have been studied.

  1. EURAC: A liquid target neutron spallation source using cyclotron technology

    Science.gov (United States)

    Perlado, J. M.; Mínguez, E.; Sanz, J.; Piera, M.

    1995-09-01

    Euratom/JRC Ispra led some years ago the design of an accelerator based neutron spallation source EURAC, with special emphasis as a fusion material testing device. DENIM was involved in the development of the last version of this source. EURAC proposes to use a beam of 600 MeV or 1.5 GeV protons, produced by an effective and low cost ring cyclotron with a current of 6 mA impinging in a liquid lead, or lead-bismuth, target. It will use an advanced cyclotron technology which can be implemented in the next future, in the line of the actual technology of the upgraded SIN-type cyclotron. The adjacent rows to the target correspond to the lead, or Li17Pb83, cooled channels where the samples will be located. The available volumes there were shown enough for material testing purposes. Here, proposal of using those experimental areas to introduce small masses of radioactive wastes for testing of transmutation in spallation source is made. In addition, extrapolation of present conceptual design to make available larger volumes under flexible conditions seems to be possible. Neutrons leaking from the test zone drive a subcritical booster (hidrogen moderator in the center.

  2. High energy physics program at Texas A&M University. Final report, April 1, 1990--March 31, 1991

    Energy Technology Data Exchange (ETDEWEB)

    1992-12-01

    The Texas A&M experimental high energy physics program has been supported since its inception by DOE Contract DE-AS05-81ER40039. During that period we established a viable experimental program at a university which before this time had no program in high energy physics. In 1990, the experimental program was augmented with a program in particle theory. In the accompanying final report, we outline the research work accomplished during the final year of this contract and the program being proposed for consideration by the Department of Energy for future grant support. Some of the particular areas covered are: Collider detector at Fermilab program; the TAMU MACRO program; SSC R&D program; SSC experimental program; and theoretical physics program.

  3. Theoretical and experimental study of cyclotronic waves in a fusion plasma; Etude theorique et experimentale des ondes cyclotroniques electroniques dans un plasma de fusion

    Energy Technology Data Exchange (ETDEWEB)

    Vezard, D.

    1994-12-20

    This thesis presents a study concerning cyclotronic waves in a plasma. It starts with an illustration of the elementary interaction between electromagnetic waves and matter.It shows that electrons from tokamak absorbs waves at cyclotronic frequency. Cyclotronic waves are studied by solving the dispersion relation in plasma; it concerns polarisation, absorption, dispersion, extinction. Then, classical theories are reminded in order to speak about decoupled electrons and their interactions. Absorption and emission properties of cyclotronic waves by electrons from a queue are described. After that, cyclotronic waves propagation is studied taking into account resonance. The last part of this thesis is dedicated to the electronic distribution function that is made by a wave spectra at a inferior hybrid frequency. (TEC). 129 refs., 75 figs.

  4. Neutron field inside a PET Cyclotron vault room

    Energy Technology Data Exchange (ETDEWEB)

    Vega C, H.R. [UAZ, C. Cipres 10, 98068 Zacatecas (Mexico); Mendez, R. [CIEMAT, Ave. Complutense 22, 28040 Madrid (Spain); Iniguez, M.P. [Universidad de Valladolid, Po Prado de la Magdalena s/n, 47011 Valladolid (Spain); Climent, J.M.; Penuelas, I. [Servicio de Medicina Nuclear de la Clinica Universitaria de Navarra, Pamplona (Spain); Barquero, R. [Hospital Universitario Rio Hortega, Valladolid (Spain)]. e-mail: fermineutron@yahoo.com

    2006-07-01

    The neutron field around a Positron Emission Tomography cyclotron was investigated during {sup 18} F radioisotope production with an 18 MeV proton beam. In this study the Ion Beam Application cyclotron, model Cyclone 18/9, was utilized. Measurements were carried out with a Bonner sphere neutron spectrometer with pairs of thermoluminescent dosemeters (TLD600 and TLD700) as thermal neutron detector. The TLDs readouts were utilized to unfold the neutron spectra at three different positions inside the cyclotron's vault room. With the spectra the Ambient dose equivalent was calculated. Neutron spectra unfolding were performed with the BUNKIUT code and the UTA4 response matrix. Neutron spectra were also determined by Monte Carlo calculations using a detailed model of cyclotron and vault room. (Author)

  5. Complete excavation and mapping of a Texas leafcutting ant nest

    Science.gov (United States)

    John C. Moser

    2006-01-01

    A medium-sized nest of the Texas leafcutting ant, Atta texana (Buckley), in northern Louisiana was excavated completely, and a three-dimensional model of its external and subterranean features was constructed. In total, 97 fungus gardens, 27 dormancy cavities, and 45 detritus cavities were located. At the lower center of the funnel-shaped nest was a...

  6. The cyclotron laboratory and the RFQ accelerator in Bern

    Science.gov (United States)

    Braccini, S.; Ereditato, A.; Kreslo, I.; Nirkko, M.; Scampoli, P.; von Bremen, K.; Weber, M.

    2013-07-01

    Two proton accelerators have been recently put in operation in Bern: an 18 MeV cyclotron and a 2 MeV RFQ linac. The commercial IBA 18/18 cyclotron, equipped with a specifically conceived 6 m long external beam line ending in a separate bunker, will provide beams for routine 18-F and other PET radioisotope production as well as for novel detector, radiation biophysics, radioprotection, radiochemistry and radiopharmacy developments. The accelerator is embedded into a complex building hosting two physics laboratories and four Good Manufacturing Practice (GMP) laboratories. This project is the result of a successful collaboration between the Inselspital, the University of Bern and private investors, aiming at the constitution of a combined medical and research centre able to provide the most cutting-edge technologies in medical imaging and cancer radiation therapy. The cyclotron is complemented by the RFQ with the primary goals of elemental analysis via Particle Induced Gamma Emission (PIGE), and the detection of potentially dangerous materials with high nitrogen content using the Gamma-Resonant Nuclear Absorption (GRNA) technique. In this context, beam instrumentation devices have been developed, in particular an innovative beam profile monitor based on doped silica fibres and a setup for emittance measurements using the pepper-pot technique. On this basis, the establishment of a proton therapy centre on the campus of the Inselspital is in the phase of advanced study.

  7. The cyclotron laboratory and the RFQ accelerator in Bern

    Energy Technology Data Exchange (ETDEWEB)

    Braccini, S.; Ereditato, A.; Kreslo, I.; Nirkko, M.; Weber, M. [Albert Einstein Center for Fundamental Physics, Laboratory for High Energy Physics (LHEP), University of Bern, Sidlerstrasse 5, CH-3012 Bern (Switzerland); Scampoli, P. [Albert Einstein Center for Fundamental Physics, Laboratory for High Energy Physics (LHEP), University of Bern, Sidlerstrasse 5, CH-3012 Bern, Switzerland and Department of Physical Sciences, University Federico II, Via Cintia, I-60126 Napoli (Italy); Bremen, K. von [SWAN Isotopen AG, Inselspital, CH-3010 Bern (Switzerland)

    2013-07-18

    Two proton accelerators have been recently put in operation in Bern: an 18 MeV cyclotron and a 2 MeV RFQ linac. The commercial IBA 18/18 cyclotron, equipped with a specifically conceived 6 m long external beam line ending in a separate bunker, will provide beams for routine 18-F and other PET radioisotope production as well as for novel detector, radiation biophysics, radioprotection, radiochemistry and radiopharmacy developments. The accelerator is embedded into a complex building hosting two physics laboratories and four Good Manufacturing Practice (GMP) laboratories. This project is the result of a successful collaboration between the Inselspital, the University of Bern and private investors, aiming at the constitution of a combined medical and research centre able to provide the most cutting-edge technologies in medical imaging and cancer radiation therapy. The cyclotron is complemented by the RFQ with the primary goals of elemental analysis via Particle Induced Gamma Emission (PIGE), and the detection of potentially dangerous materials with high nitrogen content using the Gamma-Resonant Nuclear Absorption (GRNA) technique. In this context, beam instrumentation devices have been developed, in particular an innovative beam profile monitor based on doped silica fibres and a setup for emittance measurements using the pepper-pot technique. On this basis, the establishment of a proton therapy centre on the campus of the Inselspital is in the phase of advanced study.

  8. A remotely steered millimetre wave launcher for electron cyclotron heating and current drive on ITER

    NARCIS (Netherlands)

    Bongers, W. A.; M. F. Graswinckel,; Goede, A. P. H.; Kasparek, W.; Danilov, I.; Curto, A. F.; M.R. de Baar,; van den Berg, M. A.; Donne, A. J. H.; Elzendoorn, B. S. Q.; Heidinger, R.; Ivanov, P.; Kruijt, O. G.; Lamers, B.; Meier, A.; Piosczyk, B.; Plaum, B.; Ronden, D. M. S.; Thoen, D. J.; Schmid, M.; Verhoeven, A. G. A.

    2010-01-01

    High-power millimetre wave beams employed on ITER for heating and Current drive at the 170 GHz electron cyclotron resonance frequency require agile steering and tight focusing of the beams to suppress neoclassical tearing modes. This paper presents experimental validation of the remote steering (RS)

  9. Cyclotron produced 198gAu, a potential radionuclide for diagnostic and therapeutic applications

    Science.gov (United States)

    Khandaker, Mayeen Uddin; Haba, Hiromitsu; Kassim, Hasan Abu

    2016-02-01

    Production cross-sections of the natPt(d,x)198Au reactions have been measured from a 24-MeV deuteron energy down to the threshold by using a stacked-foil activation technique combined with HPGe γ-ray spectrometry. Only a partial agreement is obtained with the existing literature data and the theoretical data extracted from the TENDL-2013 library. Physical thick target yield for the 198Au radionuclide was deduced using the measured cross-sections, and found a general agreement with the directly measured yield available in the literature. This study reveals that a low deuteron energy (<15 MeV) cyclotron and an enriched 198Pt (100%) target could be used to obtain 198Au in no carrier added form.

  10. Mechanical design control and implementation of a new movable diagnostic probe for the TRIUMF cyclotron

    Science.gov (United States)

    Ries, Thomas C.

    1994-10-01

    A new movable probe has been installed into the TRIUMF H- cyclotron. It is intended to measure the distribution of betatron amplitudes, in the vertical plane, of the circulating beam and to scrape halo. The probe, however, may also be scanned in the radial direction. The head may be positioned vertically and horizontally to an accuracy of 0.002`. The device is mechanically modular to facilitate fast and easy handling for maintenance in a radioactive area. The beam sensor on the probe head is a 1.25`×3`×0.003` tantalum foil and its overall coverage is 3.00`×7.25` in a vertical plane orthogonal to, and crossing through the beam orbit plane. Presently its radial center line location corresponds to a proton beam energy of about 430 MeV at radius 296`, however, the probe device may be easily relocated to operate from any 4` port, and, with an adaptor port flange, may be installed into any port in the cyclotron vacuum tank. A stationary catcher below the probe path collects those electrons stripped from the H- beam and scattered out from the probe head. The probe axis is vertical and the tank aperture is narrow so a worm gear arrangement combined with a modified ``Evans''-parallel linkage mechanism is used to transform vertical rotary motion into horizontal linear motion. The actuators are dc servo motors with tachometers driven by pulse width modulated servo amplifiers. Position sensing is done by variable reluctance type absolute rotary encoders and the higher level positioning is performed by TRIMAC based control software. The precision of movement and jitter was measured in the laboratory. Examples will be given of the probe use with beam.

  11. Cyclotron produced {sup 67}Ga, a potential radionuclide for diagnostic and therapeutic applications

    Energy Technology Data Exchange (ETDEWEB)

    Khandaker, Mayeen Uddin, E-mail: mu-khandaker@um.edu.my; Kassim, Hasan Abu [Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia); Haba, Hiromitsu [Nishina Center for Accelerator-Based Science, RIKEN, Wako, Saitama 351-0198 (Japan)

    2015-04-29

    Production cross-sections of the {sup nat}Zn(d,x){sup 67}Ga reactions have been measured from a 24-MeV deuteron energy down to the threshold by using a stacked-foil activation technique combined with HPGe γ-ray spectrometry. An overall good agreement is found with some of the earlier measurements, whereas a partial agreement is obtained with the theoretical data extracted from the TENDL-2013 library. Physical thick target yield for the {sup 67}Ga radionuclide was deduced using the measured cross-sections, and found in agreement with the directly measured yield available in the literature. This study reveals that a low deuteron energy (<11 MeV) cyclotron and an enriched {sup 66}Zn target could be used to obtain {sup 67}Ga in no carrier added form.

  12. Cyclotron produced 67Ga, a potential radionuclide for diagnostic and therapeutic applications

    Science.gov (United States)

    Khandaker, Mayeen Uddin; Haba, Hiromitsu; Kassim, Hasan Abu

    2015-04-01

    Production cross-sections of the natZn(d,x)67Ga reactions have been measured from a 24-MeV deuteron energy down to the threshold by using a stacked-foil activation technique combined with HPGe γ-ray spectrometry. An overall good agreement is found with some of the earlier measurements, whereas a partial agreement is obtained with the theoretical data extracted from the TENDL-2013 library. Physical thick target yield for the 67Ga radionuclide was deduced using the measured cross-sections, and found in agreement with the directly measured yield available in the literature. This study reveals that a low deuteron energy (<11 MeV) cyclotron and an enriched 66Zn target could be used to obtain 67Ga in no carrier added form.

  13. The ion cyclotron turbulence generated by a low frequency kinetic Alfven wave, and the related turbulent heating of ions

    Science.gov (United States)

    Mykhaylenko, Volodymyr S.; Mykhaylenko, Volodymyr V.; Lee, Hae June

    2017-10-01

    The ion cyclotron instability driven by the strong kinetic Alfven wave is investigated as a possible source of the anisotropic heating of ions in the coronal holes and solar wind. We present a novel model of a plasma with coupled inhomogeneous current and the sheared flow, which follows from the studies of the particles motion in the electric field of the kinetic Alfven wave of the finite wavelength. The investigation is performed employing the non-modal kinetic theory grounded on the shearing modes approach. The solution of the governing linear integral equation for the perturbed potential displays that the flow velocity shear, which for the corona conditions may be above the growth rate of the ion cyclotron instability in plasma with steady current, changes the exponential growth of the ion cyclotron potential on the power function of time, that impedes the growth of the unstable ion cyclotron wave and reduces the turbulent heating rate of ions across the magnetic field. This work was funded by National R&D Program through the National Research Foundation of Korea (NRF) (Grant No. NRF-2015R1D1A1A01061160).

  14. Benchmarking of codes for electron cyclotron heating and electron cyclotron current drive under ITER conditions

    NARCIS (Netherlands)

    Prater, R.; Farina, D.; Gribov, Y.; Harvey, R. W.; Ram, A. K.; Lin-Liu, Y. R.; Poli, E.; Smirnov, A. P.; Volpe, F.; Westerhof, E.; Zvonkovo, A.

    2008-01-01

    Optimal design and use of electron cyclotron heating requires that accurate and relatively quick computer codes be available for prediction of wave coupling, propagation, damping and current drive at realistic levels of EC power. To this end, a number of codes have been developed in laboratories

  15. Intense highly charged ion beam production and operation with a superconducting electron cyclotron resonance ion source

    Directory of Open Access Journals (Sweden)

    H. W. Zhao

    2017-09-01

    Full Text Available The superconducting electron cyclotron resonance ion source with advanced design in Lanzhou (SECRAL is a superconducting-magnet-based electron cyclotron resonance ion source (ECRIS for the production of intense highly charged heavy ion beams. It is one of the best performing ECRISs worldwide and the first superconducting ECRIS built with an innovative magnet to generate a high strength minimum-B field for operation with heating microwaves up to 24–28 GHz. Since its commissioning in 2005, SECRAL has so far produced a good number of continuous wave intensity records of highly charged ion beams, in which recently the beam intensities of ^{40}Ar^{12+} and ^{129}Xe^{26+} have, for the first time, exceeded 1 emA produced by an ion source. Routine operations commenced in 2007 with the Heavy Ion accelerator Research Facility in Lanzhou (HIRFL, China. Up to June 2017, SECRAL has been providing more than 28,000 hours of highly charged heavy ion beams to the accelerator demonstrating its great capability and reliability. The great achievement of SECRAL is accumulation of numerous technical advancements, such as an innovative magnetic system and an efficient double-frequency (24+18  GHz heating with improved plasma stability. This article reviews the development of SECRAL and production of intense highly charged ion beams by SECRAL focusing on its unique magnet design, source commissioning, performance studies and enhancements, beam quality and long-term operation. SECRAL development and its performance studies representatively reflect the achievements and status of the present ECR ion source, as well as the ECRIS impacts on HIRFL.

  16. Intense highly charged ion beam production and operation with a superconducting electron cyclotron resonance ion source

    Science.gov (United States)

    Zhao, H. W.; Sun, L. T.; Guo, J. W.; Lu, W.; Xie, D. Z.; Hitz, D.; Zhang, X. Z.; Yang, Y.

    2017-09-01

    The superconducting electron cyclotron resonance ion source with advanced design in Lanzhou (SECRAL) is a superconducting-magnet-based electron cyclotron resonance ion source (ECRIS) for the production of intense highly charged heavy ion beams. It is one of the best performing ECRISs worldwide and the first superconducting ECRIS built with an innovative magnet to generate a high strength minimum-B field for operation with heating microwaves up to 24-28 GHz. Since its commissioning in 2005, SECRAL has so far produced a good number of continuous wave intensity records of highly charged ion beams, in which recently the beam intensities of 40Ar+ and 129Xe26+ have, for the first time, exceeded 1 emA produced by an ion source. Routine operations commenced in 2007 with the Heavy Ion accelerator Research Facility in Lanzhou (HIRFL), China. Up to June 2017, SECRAL has been providing more than 28,000 hours of highly charged heavy ion beams to the accelerator demonstrating its great capability and reliability. The great achievement of SECRAL is accumulation of numerous technical advancements, such as an innovative magnetic system and an efficient double-frequency (24 +18 GHz ) heating with improved plasma stability. This article reviews the development of SECRAL and production of intense highly charged ion beams by SECRAL focusing on its unique magnet design, source commissioning, performance studies and enhancements, beam quality and long-term operation. SECRAL development and its performance studies representatively reflect the achievements and status of the present ECR ion source, as well as the ECRIS impacts on HIRFL.

  17. Safety and protection problems in the management of a plant with cyclotron, radiopharmacy laboratory and PET/CT equipment

    Energy Technology Data Exchange (ETDEWEB)

    Russo, A.; Speranza, A.; Panico, M. [University Federico-2, National Research Council - Institute of Biostructures and Bioimaging and Dept. of Bio-morphological and Functional Sciences, Napoli (Italy); Delia, R. [University La Sapienza - sez. Rieti, Faculty of Medicine, Rome (Italy); Casale, M. [University Federico-2, Dept. of Physics - Health Physics School, Napoli (Italy); Salvatore, M. [University Federico-2 and National Research Council - Institute of Biostructures and Bioimaging, Dept. of Bio-morphological and Functional Sciences, Napoli (Italy)

    2006-07-01

    The importance of Positron Emission Tomography (PET) is spreading and increasing in many clinical diagnostic fields, as well as the oncology, the cardiology, the neurology and so on. A strong input to the diffusion of this imaging technique from the research field to clinical one has been given either by the development of knowledge about PET or the modern technologies, which allow to set up at very suitable prices and in very little volumes, like in an hospital site, complete systems, which consist of: Cyclotron; Radiopharmacy Laboratory; one or more either PET or PET/CT. Such set-up arrangement allows to carry out highly innovative diagnostic examinations with a remarkable achievement of diagnostic quality and large number of daily examinations. In this paper the authors show the achieved know-how with respect to radioprotection for the set-up and running management of two systems such as PET/CT tomography unit, cyclotron and radiopharmacy laboratory, installed one in the Imaging Diagnostic Department of the Hospital of Naples University and used only for medical and research purposes, and the other one in A.C.O.M. (Advanced Center of Oncology in Macerata), used for commercial and research purposes. The following safety problems have been considered: the facility lay-out; the optimisation of the paths either for the operator, or the patients and the radiotracers; the guide lines for the protection and the safety of the patients, operators and general population, in relation to the utilization and the management of either the more common radiotracers (18 F and 11 C) or those in research progress, for example 64 Cu and 124 I; the protocol set up for the image quality control in relation to the patient protection and safety. The above problems have also been considered, taking into account the Italian regulation and the International Recommendations. (authors)

  18. Assessment of radionuclidic impurities in cyclotron produced (99m)Tc.

    Science.gov (United States)

    Lebeda, Ondřej; van Lier, Erik J; Štursa, Jan; Ráliš, Jan; Zyuzin, Alexander

    2012-11-01

    The commercial viability of cyclotron-produced (99m)Tc as an alternative to generator-produced (99m)Tc depends on several factors. These include: production yield, ease of target processing and recycling of (100)Mo, radiochemical purity, specific activity as well as the presence of other radionuclides, particularly various Tc radioisotopes that cannot be separated chemically and will remain in the final clinical preparation. These Tc radionuclidic impurities are derived from nuclear interactions of the accelerated protons with other stable Mo isotopes present in the enriched (100)Mo target. The aim of our study was to determine experimentally the yields of Tc radioisotopes produced from these stable Mo isotopes as a function of incident beam energy in order to predict radionuclidic purity of (99m)Tc produced in highly enriched (100)Mo targets of known isotopic composition. Enriched molybdenum targets of (95)Mo, (96)Mo, (97)Mo, (98)Mo and (100)Mo were prepared by pressing powdered metal into an aluminum target support. The thick targets were bombarded with 10 to 24MeV protons using the external beam line of the U-120M cyclotron of the Nuclear Physics Institute, Řež. The thick target yields of (94)Tc, (94m)Tc, (95)Tc, (95m)Tc, (96m+g)Tc and (97m)Tc were derived from their activities measured by γ spectrometry using a high purity Ge detector. These data were then used to assess the effect of isotopic composition of highly enriched (100)Mo targets on the radionuclidic purity of (99m)Tc as a function of proton beam energy. Estimates were validated by comparison to measured activities of Tc radioisotopes in proton irradiated, highly enriched (100)Mo targets of known isotopic composition. The measured thick target yields of (94)Tc, (94m)Tc, (95)Tc, (95m)Tc, (96m+g)Tc and (97m)Tc correspond well with recently published values calculated via the EMPIRE-3 code. However, the measured yields are more favourable with regard to achievable radionuclidic purity of (99m

  19. The radioprotection management of a PET department with a cyclotron and radiopharmacy laboratory, in accordance with Italian legislation.

    Science.gov (United States)

    Russo, A A; Ferrari, P; Casale, M; Delia, R

    2011-09-01

    The possibility of setting up a positron emission tomography (PET) facility with a cyclotron and radiopharmaceutical laboratory in situ, at a feasible price and in a very restricted space, has led to a steady increase both in the use of the PET technique in diagnostic clinical routine imaging and in the number of cyclotrons for drug production. Owing to the progress made in the PET procedures, it is now possible to have not only a highly innovative system of diagnostic examination, with a remarkable improvement in the diagnostic quality and patient care, but also a considerable increase in the number of daily examinations. In this paper, the authors show how the acquired know-how, with respect to radioprotection, has applied to the planning, running and management of the PET/CT unit, installed in the Imaging Diagnostic Department of the Policlinico Tor Vergata (PTV), at Tor Vergata University, Rome.

  20. Single-electron detection and spectroscopy via relativistic cyclotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Asner, David M.; Bradley, Rich; De Viveiros Souza Filho, Luiz A.; Doe, Peter J.; Fernandes, Justin L.; Fertl, M.; Finn, Erin C.; Formaggio, Joseph; Furse, Daniel L.; Jones, Anthony M.; Kofron, Jared N.; LaRoque, Benjamin; Leber, Michelle; MCBride, Lisa; Miller, M. L.; Mohanmurthy, Prajwal T.; Monreal, Ben; Oblath, Noah S.; Robertson, R. G. H.; Rosenberg, Leslie; Rybka, Gray; Rysewyk, Devyn M.; Sternberg, Michael G.; Tedeschi, Jonathan R.; Thummler, Thomas; VanDevender, Brent A.; Woods, N. L.

    2015-04-01

    It has been understood since 1897 that accelerating charges should emit electromagnetic radiation. Cyclotron radiation, the particular form of radiation emitted by an electron orbiting in a magnetic field, was first derived in 1904. Despite the simplicity of this concept, and the enormous utility of electron spectroscopy in nuclear and particle physics, single-electron cyclotron radiation has never been observed directly. Here we demonstrate single-electron detection in a novel radiofrequency spectrometer. We observe the cyclotron radiation emitted by individual electrons that are produced with mildly-relativistic energies by a gaseous radioactive source and are magnetically trapped. The relativistic shift in the cyclotron frequency permits a precise electron energy measurement. Precise beta electron spectroscopy from gaseous radiation sources is a key technique in modern efforts to measure the neutrino mass via the tritium decay endpoint, and this work is a proof-of-concept for future neutrino mass experiments using this technique.

  1. Ernest Orlando Lawrence (1901-1958), Cyclotron and Medicine

    Energy Technology Data Exchange (ETDEWEB)

    Chu, William T.

    2005-09-01

    On August 8, 2001, Lawrence Berkeley National Laboratory celebrated the centennial of the birth of its founder (and namesake), Ernest Orlando Lawrence. For the occasion, many speeches were given and old speeches were remembered. We recall the words of the late Luis Alvarez, a Nobel Laureate and one of the Lawrence's closest colleagues: ''Lawrence will always be remembered as the inventor of the cyclotron, but more importantly, he should be remembered as the inventor of the modern way of doing science''. J. L. Heilbron and R. W. Seidel, in the introduction of their book, ''Lawrence and His Laboratory'' stated, ''The motives and mechanisms that shaped the growth of the Laboratory helped to force deep changes in the scientific estate and in the wider society. In the entrepreneurship of its founder, Ernest Orlando Lawrence, these motives, mechanisms, and changes came together in a tight focus. He mobilized great and small philanthropists, state and local governments, corporations, and plutocrats, volunteers and virtuosos. The work they supported, from astrophysics and atomic bombs, from radiochemistry to nuclear medicine, shaped the way we observe, control, and manipulate our environment.'' Indeed, all over the civilized world, the ways we do science changed forever after Lawrence built his famed Radiation Laboratory. In this editorial, we epitomize his legacy of changing the way we do medicine, thereby affecting the health and well being of all humanity. This year marks the 75th anniversary of the invention of the cyclotron by Ernest Orlando Lawrence at the University of California at Berkeley. Lawrence conceived the idea of the cyclotron early in 1929 after reading an article by Rolf Wideroe on high-energy accelerators. In the spring of 1930 one of his students, Nels Edlefsen, constructed two crude models of a cyclotron. Later in the fall of the same year, another student, M. Stanley Livingston

  2. A proposal for a novel H ion source based on electron cyclotron resonance heating and surface ionization

    Energy Technology Data Exchange (ETDEWEB)

    Tarvainen, Ollie A [Los Alamos National Laboratory; Kurennoy, Sergey [Los Alamos National Laboratory

    2008-01-01

    A design for a novel H{sup -} ion source based on electron cyclotron resonance plasma heating and surface ionization is presented. The plasma chamber of the source is an rf-cavity designed for TE{sub 111} eigenmode at 2.45 GHz. The desired mode is excited with a loop antenna. The ionization process takes place on a cesiated surface of a biased converter electrode. The H{sup -} ion beam is further 'self-extracted' through the plasma region. The magnetic field of the source is optimized for plasma generation by electron cyclotron resonance heating, and beam extraction. The design features of the source are discussed in detail and the attainable H{sup -} ion current, beam emittance and duty factor of the novel source are estimated.

  3. How a disaster preparedness rotation helps teach the seven NAVMEC professional competencies: the Texas A&M University Experience.

    Science.gov (United States)

    Bissett, Wesley T; Zoran, Debra L; Clendenin, Angela; Espitia, Noberto F; Moyer, William; Rogers, Kenita S

    2013-01-01

    Changing societal expectations provide new challenges and opportunities for the veterinary medical profession. These changing expectations and approaches to the education of veterinary students in the future are reflected in the North American Veterinary Medical Education Consortium's report "Roadmap for Veterinary Medical Education in the 21st Century: Responsive, Collaborative, Flexible." They are also reflected in the expectations of the populace, who no longer find it acceptable that animals are not included in both planning for and responding to natural or manmade disasters. In response to the changing needs of society and the veterinary profession, Texas A&M University College of Veterinary Medicine has developed a required rotation in the fourth-year curriculum on emergency planning and response. The unique requirements of emergency preparedness and response and the design of the rotation provide an ideal platform for providing this valued public service while simultaneously addressing the seven professional competencies outlined in the NAVMEC roadmap. This article describes an overview of the rotation and its content and identifies opportunities for students to practice these important professional competencies using the tools introduced in this new rotation.

  4. Coaxial ring cyclotron as a perspective nuclear power engineering machine

    CERN Document Server

    Tumanyan, A R; Mkrtchyan, R L; Amatuni, T A; Avakian, R O; Khudaverdian, A G

    1995-01-01

    Coaxial Ring Cyclotron (CRC) is described, and its main advantages, such as simple injection technique, several injected beams summation option, high efficiency, are considered. The proposed proton accelerator is a perspective machine for the solution of the main problems of the present day nuclear power engineering as well as for the next-generation nuclear power plants, representing a combination of subcritical reactors and particle accelerators. The possibility of installation of CRCs into ring accelerators with an average diameter from 60 to 100m, e.g., the Yerevan electron synchrotron, is considered.

  5. Atlas of Formability: NICKELVAC K-500

    Science.gov (United States)

    1992-10-31

    representative of those used in metalforming practices. From the stress-strain curves, the flow behavior was characterized and a processing map...Bulletin. In some metalworking processes such as forging, strain rate varies within the workpiece. An analysis of the process with finite element method...Furthermore, FEM analysis with the data from the Atlas of Formability can be coupled with fracture criteria to predict defect formation in metalworking

  6. Developing and Planning a Texas Based Homeschool Curriculum

    Science.gov (United States)

    Terry, Bobby K.

    2011-01-01

    Texas has some of the lowest SAT scores in the nation. They are ranked 36th nationwide in graduation rates and teacher salaries rank at number 33. The public school system in Texas has problems with overcrowding, violence, and poor performance on standardized testing. Currently 300,000 families have opted out of the public school system in order…

  7. Magnetic field calculation for a 13 MeV PET cyclotron

    CERN Document Server

    Yang, W Y; Oh, S; Chai, J S; Ha, J H

    1999-01-01

    A design study of the main magnet for a 13 MeV cyclotron has been carried out in a joint collaboration between the Korea Cancer Center Hospital (KCCH) and POSTECH. A maximum energy of 13 MeV has been chosen to produce radioisotopes such as /sup 18/F. There are four magnet sectors, each with radial-ridged shape. Maximum magnetic fields are 1.85 T and 0.48 T at hill and valley centers, respectively. The total size of the cyclotron is less than 2 m in diameter. The program TOSCA has been utilized for the field calculation and optimization. In this paper, we describe design parameters of the 13 MeV PET cyclotron, with emphasis on the magnetic field shape and the beam optics calculation. (3 refs).

  8. A simple thick target for production of 89Zr using an 11 MeV cyclotron

    Science.gov (United States)

    Link, Jeanne M.; Krohn, Kenneth A.; O’Hara, Matthew J.

    2017-01-01

    The growing interest but limited availability of 89Zr for PET led us to test targets for the 89Y(p,n) reaction. The goal was an easily constructed target for an 11 MeV Siemens cyclotron. Yttrium foils were tested at different thicknesses, angles and currents. A 90° foil tolerated 41 μA without damage and produced ~800 MBq/h, > 20 mCi, an amount adequate for radiochemistry research and human doses in a widely available accelerator. This method should translate to higher energy cyclotrons. PMID:28187357

  9. Measurements of beam emittance, accelerated RF phase band, and centring in a 1 MeV test cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Dehnel, M.P.; Erdman, K.L. [Obco Technologies Inc., Richmond B.C. (Canada); Kuo, T. [TRIUMF, Vancouver B.C. (Canada)

    1999-07-01

    Differential probe measurements of radial and axial circulating beam intensity in the EBCO/TRIUMF 1 MeV H{sup -} Test Cyclotron have been made. Intensity profile simulations from an analytical model compare well with the measured beam intensity data, and yield important beam related quantities such as the emittance, the accelerated RF phase band and the beam centring. The experimental hardware details, comparisons of measured and computed data, and a description of the analytical model are reported. (authors)

  10. Whistler-cyclotron spontaneous fluctuations. A proxy to identify thermal and non-thermal electrons?

    Science.gov (United States)

    Moya, P. S.; López, R. A.; Navarro, R.; Vinas, A. F.; Munoz, V.; Araneda, J. A.; Valdivia, J. A.

    2016-12-01

    Observed electron velocity distributions in the space plasmas exhibit a variety of non-thermal features which deviate from thermal equilibrium, in the form of temperature anisotropies, suprathermal tails, and field aligned beams. The state close to thermal equilibrium and its departure from it provides a source for spontaneous emissions of electromagnetic fluctuations. For example, the whistler cyclotron waves at electron scales. Here we present a comparative analysis of these fluctuations based upon anisotropic plasma modeled with thermal and non-thermal particle distributions. The analysis presented here considers the second-order theory of fluctuations and the dispersion relation of weakly transverse fluctuations, with wave vectors parallel to the uniform background magnetic field, in a finite temperature isotropic magnetized electron-proton plasma modeled with bi-Maxwellian and kappa-like distributions. Dispersion analysis and stability thresholds are derived for these non-thermal distributions and compared with similar results obtained from PIC simulations using plasma and field parameters relevant to space nearly collisionless environments. Our results indicate that there is a strong dependence between the shape of the velocity distribution function and the spontaneous magnetic fluctuations wave spectrum. This feature may be used proxy to identify the nature of electron populations in space plasmas when high resolution particle instruments are not available.

  11. Production of copper-64 and gallium-68 with a medical cyclotron using liquid targets

    Science.gov (United States)

    Alves, F.; Alves, V. H. P.; Do Carmo, S. J. C.; Neves, A. C. B.; Silva, M.; Abrunhosa, A. J.

    2017-06-01

    This work describes the production of two clinically relevant metal radioisotopes 64Cu and 68Ga with a medical cyclotron by the irradiation of liquid targets. New results are presented for the implementation of this methodology in a fully automated system, using commercially available equipment. Liquid target solutions containing enriched 64Ni and 68Zn were loaded, bombarded and transferred to synthesis modules where a purified solution containing the desired radiometal is obtained and can then be used to further radiolabeling within only one hour after End-Of-Bombardment (EOB). Typical production runs using enriched material lead to the production of 5 GBq and 6 GBq (0.14 MBq/(μAh ṡ mg) and 1.5 MBq/(μAh ṡ mg)) of 64Cu and 68Ga; although the technique can be used to obtain up to 25 GBq and 40 GBq, respectively, by simply scaling up the amount of the enriched material. Purified solutions containing 64Cu and 68Ga were obtained within 30 min after EOB and used to produce 64Cu-ATSM and 68Ga-DOTA-NOC, respectively, with quality parameters suitable for human use.

  12. Electron cyclotron resonance discharge as a source for hydrogen and deuterium ions production

    Energy Technology Data Exchange (ETDEWEB)

    Chacon Velasco, A.J. [Universidad de Pamplona, Pamplona (Colombia); Dougar-Jabon, V.D. [Universidad Industrial de Santander, Bucaramanga (Colombia)

    2004-07-01

    In this report, we describe characteristics of a ring-structure hydrogen plasma heated in electron cyclotron resonance conditions and confined in a mirror magnetic trap and discuss the relative efficiency of secondary electrons and thermo-electrons in negative hydrogen and deuterium ion production. The obtained data and calculations of the balance equations for possible reactions demonstrate that the negative ion production is realized in two stages. First, the hydrogen and deuterium molecules are excited in collisions with the plasma electrons to high-laying Rydberg or vibrational levels in the plasma volume. The second stage leads to the negative ion production through the process of dissociative attachment of low energy electrons. The low energy electrons are originated due to a bombardment of the plasma electrode by ions of one of the driven rings and thermo-emission from heated tungsten filaments. Experiments seem to indicate that the negative ion generation occurs predominantly in the limited volume filled with thermo-electrons. Estimation of the negative ion generation rate shows that the main channel of H{sup -} and D{sup -} ion production involves the process of high Rydberg state excitation. (authors)

  13. Measurement and control of the air contamination generated in a medical cyclotron facility for PET radiopharmaceuticals.

    Science.gov (United States)

    Calandrino, R; del Vecchio, A; Todde, S; Fazio, F

    2007-05-01

    The aim of this paper is to report the data concerning the contamination of the exhausted air from the hot cells dedicated to the large-scale synthesis of positron emission tomography (PET) radiopharmaceuticals. Two cyclotrons are currently operating in Ospedale San Raffaele for the routine production of C and F. They are linked with four radiochemistry laboratories by means of shielded radioisotope delivery lines. The above labs are dedicated both to the large scale preparation and to the research and development of PET radiopharmaceuticals. The department hosts four CT-PET scanners, which operate with a mean patient workload of 40 per day. Radiosyntheses are performed using automated modules located in 10 hot cells. The air outlets are monitored online by a 2-inch NaI(Tl) counter in a Marinelli geometry counting volume. Contamination values up to 10(5) Bq L(-1) have been measured at the hot cell exit point during the synthesis. The corresponding concentrations at the point of release in atmosphere are largely above the threshold of 1.29 Bq L(-1), defined by national regulations as the limit for free environmental release. A shielded gas storage system controlled by a dedicated, customized software program has thus been installed to prevent the potentially hazardous release of gaseous radioactive contaminants. The system has allowed us to maintain the effective dose to neighboring population groups below the limit of 10 muSv y(-1).

  14. Cyclotron waves in plasma

    CERN Document Server

    Lominadze, D G

    2013-01-01

    Cyclotron Waves in Plasma is a four-chapter text that covers the basic physical concepts of the theory of cyclotron waves and cyclotron instabilities, brought about by the existence of steady or alternating plasma currents flowing perpendicular to the magnetic field.This book considers first a wide range of questions associated with the linear theory of cyclotron oscillations in equilibrium plasmas and in electron plasmas in metals and semiconductors. The next chapter deals with the parametric excitation of electron cyclotron oscillations in plasma in an alternating electric field. A chapter f

  15. The structure of ^23Al and consequences on the depletion of ^22Na from ONe novae

    Science.gov (United States)

    Zhai, Y.; Trache, L.; Iacob, V. E.; Hardy, J. C.; Fu, C.; Al-Abdullah, T.; Nica, N.; McCleskey, M.; Golovko, V. V.; Park, H. I.; Tabacaru, G.; Banu, A.; Tribble, R. E.

    2007-04-01

    There is interest in the structure of ^23Al due to the contribution of the ^22Mg(p, γ)^23Al and ^22Na(p, γ)^23Mg reactions in the depletion of ^22Na from ONe novae. Using MARS we produced and separated pure ^23Al samples with a 48 MeV/u ^24Mg beam from the K500 cyclotron at Texas A&M University. New β and β-γ coincidence measurements were made with a thin scintillator, an HPGe detector and a fast tape transport system. Addition of a BGO Compton shield improved very much the quality of the γ spectra around the transitions from the IAS state at 7803 keV. From the measured β singles and β-γ coincidence decay spectra we obtained the ^23Al β-decay scheme, branching ratios and absolute logft values for several transitions. We clearly determined that the ^23Al ground state spin and parity is J^π=5/2^+ , not 1/2^+, and also found spectroscopic information for the states that are resonances in the ^22Na(p, γ)^23Mg reaction. It follows that the larger capture rate implied by the now-rejected lower spin value for ^23Al can not explain the missing 1275 keV cosmic γ -ray from the decay of long-lived ^22Na, the last step in the hot NeNa cycle.

  16. Distribution of thermal neutron flux around a PET cyclotron.

    Science.gov (United States)

    Ogata, Yoshimune; Ishigure, Nobuhito; Mochizuki, Shingo; Ito, Kengo; Hatano, Kentaro; Abe, Junichiro; Miyahara, Hiroshi; Masumoto, Kazuyoshi; Nakamura, Hajime

    2011-05-01

    The number of positron emission tomography (PET) examinations has greatly increased world-wide. Since positron emission nuclides for the PET examinations have short half-lives, they are mainly produced using on-site cyclotrons. During the production of the nuclides, significant quantities of neutrons are generated from the cyclotrons. Neutrons have potential to activate the materials around the cyclotrons and cause exposure to the staff. To investigate quantities and distribution of the thermal neutrons, thermal neutron fluxes were measured around a PET cyclotron in a laboratory associating with a hospital. The cyclotron accelerates protons up to 18 MeV, and the mean particle current is 20 μA. The neutron fluxes were measured during both 18F production and C production. Gold foils and thermoluminescent dosimeter (TLD) badges were used to measure the neutron fluxes. The neutron fluxes in the target box averaged 9.3 × 10(6) cm(-2) s(-1) and 1.7 × 10(6) cm(-2) s(-1) during 18F and 11C production, respectively. Those in the cyclotron room averaged 4.1 × 10(5) cm(-2) s(-1) and 1.2 × 10(5) cm(-2) s(-1), respectively. Those outside the concrete wall shielding were estimated as being equal to or less than ∼3 cm s, which corresponded to 0.1 μSv h(-1) in effective dose. The neutron fluxes outside the concrete shielding were confirmed to be quite low compared to the legal limit.

  17. A line-of-sight electron cyclotron emission receiver for electron cyclotron resonance heating feedback control of tearing modes

    DEFF Research Database (Denmark)

    Oosterbeek, J.W.; Bürger, A.; Westerhof, E.

    2008-01-01

    An electron cyclotron emission (ECE) receiver inside the electron cyclotron resonance heating (ECRH) transmission line has been brought into operation. The ECE is extracted by placing a quartz plate acting as a Fabry-Perot interferometer under an angle inside the electron cyclotron wave (ECW) beam...

  18. DNA contents in Texas bluegrass (Poa arachnifera) selected in Texas and Oklahoma determined by flow cytometry

    Science.gov (United States)

    Texas bluegrass (Poa arachnifera Torr.) is a dioecious, perennial, cool-season grass native to southern Kansas, Oklahoma, western Arkansas and most of Texas. Its major use has been for forage on rangelands in Texas and Oklahoma. More recently, interspecific hybrids between Texas bluegrass and Kentuc...

  19. The First Bachelor of Science Degree in Wind Energy in the US at Texas Tech University Authors: A. Ruiz Columbié, K. Rozsavolgyi, P. Hughes, D. Farris, A. Swift, R. Walker and M. Baker

    Science.gov (United States)

    Ruiz-Columbie, A.

    2010-12-01

    This paper presents a new Bachelor of Science Degree in Wind Energy proposal at Texas Tech University (TTU) beginning the spring 2011. It is designed to prepare the students for admission into a graduate program in wind energy, and/or employment as a professional in wind energy. The program integrates the environmental, social, economic, ethical, technical, scientific principles and practical skills the graduates will need in order to success as professionals in their field of expertise. This degree will provide a multidisciplinary education in the wind energy field through the study of subjects as wind meteorology, wind power generation, wind resource assessment, sustainable energy systems, utility systems operations, and fiscal and operational oversight. Students will be prepared to contribute in areas that include planning, development, operations, analysis and supervision of wind energy systems and projects, as well as to continue in graduate studies. Following the Texas Tech Uniform Undergraduate Degree Requirement Act, the major in Wind Energy will include 47 hours of general education courses from the TTU academic core, 18 hours of junior/senior level electives, and 55 hours of coursework in wind energy topics. A minor of 18 hours is also provided at TTU for those students with a different major who might decide to get a higher education in wind energy.

  20. Whistler Cyclotron Electromagnetic Fluctuations in a Maxwellian and Tsallis-kappa-like Plasma

    Science.gov (United States)

    Vinas, A. F.; Moya, P. S.; Navarro, R.; Araneda, J. A.

    2014-12-01

    Observed electron velocity distributions in the Earth's magnetosphere and the solar wind exhibit a variety of non-thermal features which deviate from thermal equilibrium, for example, in the form of temperature anisotropies, suprathermal tail extensions, and field aligned beams. The state close to thermal equilibrium and its departure from it provides a source for spontaneous emissions of electromagnetic fluctuations, such as the whistler. Here we present a comparative analysis of whistler-cyclotron fluctuations based upon anisotropic plasma modeled with Maxwellian and Tsallis kappa-like particle distributions, to explain the correspondence relationship of the magnetic fluctuations as a function of the electron temperature and thermal anisotropy in the solar wind and magnetosphere plasmas. The analysis presented here considers correlation theory of the fluctuation-dissipation theorem and the dispersion relation of transverse fluctuations, with wave vectors parallel to the uniform background magnetic field, in a finite temperature anisotropic thermal bi-Maxwellian and non-thermal Tsallis-kappa-like magnetized electron-proton plasma. Dispersion analysis and stability thresholds are derived for these thermal and non-thermal distributions using plasma and field parameters relevant to the solar wind and magnetosphere environments. Our results indicate that there is an enhancement of the fluctuations level in the case of non-thermal distributions due to the effective higher-temperature and the excess of suprathermal particles. These results suggest that a comparison of the electromagnetic fluctuations due to thermal and non-thermal distributions provides a diagnostic signature by which inferences about the nature of the particle velocity distribution function can be ascertained without in-situ particle measurements.

  1. Inverse ion-cyclotron damping and excitation of multiharmonic ion-cyclotron waves in the northern magnetospheric cusp

    Science.gov (United States)

    Slapak, Rikard; Gunell, Herbert; Hamrin, Maria

    2017-04-01

    We have investigated a case of inverse ion-cyclotron damping taking place in the northern terrestrial magnetospheric cusp, exciting waves at the ion-cyclotron frequency and its harmonics. Magnetosheath influx in the cusps and the effect of convection and magnetic mirroring give rise to parallel velocity shears, dvallel/dx\\perp, often associated with instabilities in the plasma and corresponding ion-cyclotron waves, whose evolution is described by a damping factor. This damping factor depends on, for example, the wave numbers and the velocity shear itself and can under certain conditions be negative, hence describing inverse damping (or wave growth). However, an additional required condition for inverse ion-cyclotron damping is a velocity shear in the magnetic field-aligned ion-bulk flow, and this condition is only met for magnetosheath influx in the northern cusp, as oppose to the southern cusp. The ion-cyclotron waves are primarily seen as peaks in the magnetic-field spectral densities, as presented by Slapak et al., [GRL (2016), doi:10.1002/2016GL071680]. The corresponding peaks in the electric-field spectral densities are not as profound, suggesting a background electric field noise or other processes of wave generation causing the electric spectral densities to smoothen out more compared to the magnetic counterpart. We note that some ion-cyclotron wave activity is present in a few similar shear events in the southern cusp, which indicates that other mechanisms generating ion-cyclotron waves may also be present during such conditions.

  2. Graphical user interface for yield and dose estimations for cyclotron-produced technetium.

    Science.gov (United States)

    Hou, X; Vuckovic, M; Buckley, K; Bénard, F; Schaffer, P; Ruth, T; Celler, A

    2014-07-07

    The cyclotron-based (100)Mo(p,2n)(99m)Tc reaction has been proposed as an alternative method for solving the shortage of (99m)Tc. With this production method, however, even if highly enriched molybdenum is used, various radioactive and stable isotopes will be produced simultaneously with (99m)Tc. In order to optimize reaction parameters and estimate potential patient doses from radiotracers labeled with cyclotron produced (99m)Tc, the yields for all reaction products must be estimated. Such calculations, however, are extremely complex and time consuming. Therefore, the objective of this study was to design a graphical user interface (GUI) that would automate these calculations, facilitate analysis of the experimental data, and predict dosimetry. The resulting GUI, named Cyclotron production Yields and Dosimetry (CYD), is based on Matlab®. It has three parts providing (a) reaction yield calculations, (b) predictions of gamma emissions and (c) dosimetry estimations. The paper presents the outline of the GUI, lists the parameters that must be provided by the user, discusses the details of calculations and provides examples of the results. Our initial experience shows that the proposed GUI allows the user to very efficiently calculate the yields of reaction products and analyze gamma spectroscopy data. However, it is expected that the main advantage of this GUI will be at the later clinical stage when entering reaction parameters will allow the user to predict production yields and estimate radiation doses to patients for each particular cyclotron run.

  3. Graphical user interface for yield and dose estimations for cyclotron-produced technetium

    Science.gov (United States)

    Hou, X.; Vuckovic, M.; Buckley, K.; Bénard, F.; Schaffer, P.; Ruth, T.; Celler, A.

    2014-07-01

    The cyclotron-based 100Mo(p,2n)99mTc reaction has been proposed as an alternative method for solving the shortage of 99mTc. With this production method, however, even if highly enriched molybdenum is used, various radioactive and stable isotopes will be produced simultaneously with 99mTc. In order to optimize reaction parameters and estimate potential patient doses from radiotracers labeled with cyclotron produced 99mTc, the yields for all reaction products must be estimated. Such calculations, however, are extremely complex and time consuming. Therefore, the objective of this study was to design a graphical user interface (GUI) that would automate these calculations, facilitate analysis of the experimental data, and predict dosimetry. The resulting GUI, named Cyclotron production Yields and Dosimetry (CYD), is based on Matlab®. It has three parts providing (a) reaction yield calculations, (b) predictions of gamma emissions and (c) dosimetry estimations. The paper presents the outline of the GUI, lists the parameters that must be provided by the user, discusses the details of calculations and provides examples of the results. Our initial experience shows that the proposed GUI allows the user to very efficiently calculate the yields of reaction products and analyze gamma spectroscopy data. However, it is expected that the main advantage of this GUI will be at the later clinical stage when entering reaction parameters will allow the user to predict production yields and estimate radiation doses to patients for each particular cyclotron run.

  4. Molybdenum target specifications for cyclotron production of 99mTc based on patient dose estimates.

    Science.gov (United States)

    Hou, X; Tanguay, J; Buckley, K; Schaffer, P; Bénard, F; Ruth, T J; Celler, A

    2016-01-21

    In response to the recognized fragility of reactor-produced (99)Mo supply, direct production of (99m)Tc via (100)Mo(p,2n)(99m)Tc reaction using medical cyclotrons has been investigated. However, due to the existence of other Molybdenum (Mo) isotopes in the target, in parallel with (99m)Tc, other technetium (Tc) radioactive isotopes (impurities) will be produced. They will be incorporated into the labeled radiopharmaceuticals and result in increased patient dose. The isotopic composition of the target and beam energy are main factors that determine production of impurities, thus also dose increases. Therefore, they both must be considered when selecting targets for clinical (99m)Tc production. Although for any given Mo target, the patient dose can be predicted based on complicated calculations of production yields for each Tc radioisotope, it would be very difficult to reverse these calculations to specify target composition based on dosimetry considerations. In this article, a relationship between patient dosimetry and Mo target composition is studied. A simple and easy algorithm for dose estimation, based solely on the knowledge of target composition and beam energy, is described. Using this algorithm, the patient dose increase due to every Mo isotope that could be present in the target is estimated. Most importantly, a technique to determine Mo target composition thresholds that would meet any given dosimetry requirement is proposed.

  5. Source terms, shielding calculations and soil activation for a medical cyclotron.

    Science.gov (United States)

    Konheiser, J; Naumann, B; Ferrari, A; Brachem, C; Müller, S E

    2016-12-01

    Calculations of the shielding and estimates of soil activation for a medical cyclotron are presented in this work. Based on the neutron source term from the 18O(p,n)18F reaction produced by a 28 MeV proton beam, neutron and gamma dose rates outside the building were estimated with the Monte Carlo code MCNP6 (Goorley et al 2012 Nucl. Technol. 180 298-315). The neutron source term was calculated with the MCNP6 code and FLUKA (Ferrari et al 2005 INFN/TC_05/11, SLAC-R-773) code as well as with supplied data by the manufacturer. MCNP and FLUKA calculations yielded comparable results, while the neutron yield obtained using the manufacturer-supplied information is about a factor of 5 smaller. The difference is attributed to the missing channels in the manufacturer-supplied neutron source terms which considers only the 18O(p,n)18F reaction, whereas the MCNP and FLUKA calculations include additional neutron reaction channels. Soil activation was performed using the FLUKA code. The estimated dose rate based on MCNP6 calculations in the public area is about 0.035 µSv h-1 and thus significantly below the reference value of 0.5 µSv h-1 (2011 Strahlenschutzverordnung, 9 Auflage vom 01.11.2011, Bundesanzeiger Verlag). After 5 years of continuous beam operation and a subsequent decay time of 30 d, the activity concentration of the soil is about 0.34 Bq g-1.

  6. Charting a Course through CORAL: Texas A&M University Libraries' Experience Implementing an Open-Source Electronic Resources Management System

    Science.gov (United States)

    Hartnett, Eric; Beh, Eugenia; Resnick, Taryn; Ugaz, Ana; Tabacaru, Simona

    2013-01-01

    In 2010, after two previous unsuccessful attempts at electronic resources management system (ERMS) implementation, Texas A&M University (TAMU) Libraries set out once again to find an ERMS that would fit its needs. After surveying the field, TAMU Libraries selected the University of Notre Dame Hesburgh Libraries-developed, open-source ERMS,…

  7. Regional Haze Plan for Texas and Oklahoma

    Science.gov (United States)

    EPA partially approved and partially disapproved the Texas regional haze plan. EPA also finalized a plan to limit sulfur dioxide emissions from eight Texas coal-fired electricity generating facilities

  8. Electron cyclotron resonance heating in a short cylindrical plasma ...

    Indian Academy of Sciences (India)

    Electron cyclotron resonance (ECR) plasma is produced and studied in a small cylindrical system. Microwave power is delivered by a CW magnetron at 2.45 GHz in TE10 mode and launched radially to have extraordinary (X) wave in plasma. The axial magnetic field required for ECR in the system is such that the first two ...

  9. Electron cyclotron resonance breakdown studies in a linear plasma ...

    Indian Academy of Sciences (India)

    Abstract. Electron cyclotron resonance (ECR) plasma breakdown is studied in a small linear cylindrical system with four different gases – hydrogen, helium, argon and nitrogen. Microwave power in the experimental system is delivered by a magnetron at 2.45 ± 0.02. GHz in TE10 mode and launched radially to have ...

  10. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Upper Coast of Texas: M_MAMMAL (Marine Mammal Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for dolphins and manatees for the Upper Coast of Texas. Vector polygons in this data set represent marine...

  11. Evidence of local power deposition and electron heating by a standing electromagnetic wave in electron-cyclotron-resonance plasma.

    Science.gov (United States)

    Durocher-Jean, A; Stafford, L; Dap, S; Makasheva, K; Clergereaux, R

    2014-09-01

    Microwave plasmas excited at electron-cyclotron resonance were studied in the 0.5-15 mTorr pressure range. In contrast with low-limit pressure conditions where the plasma emission highlights a fairly homogeneous spatial structure, a periodic spatial modulation (period ∼6.2 cm) appeared as pressure increased. This feature is ascribed to a local power deposition (related to the electron density) due to the presence of a standing electromagnetic wave created by the feed electromagnetic field (2.45 GHz) in the cavity formed by the reactor walls. Analysis of the electron energy probability function by Langmuir probe and optical emission spectroscopy further revealed the presence of a high-energy tail that showed strong periodic spatial modulation at higher pressure. The spatial evolution of the electron density and of the characteristic temperature of these high-energy electrons coincides with the nodes (maximum) and antinodes (minimum) of the standing wave. These spatially-modulated power deposition and electron heating mechanisms are then discussed.

  12. Predicting induced activity in the Havar foils of the (18)F production targets of a PET cyclotron and derived radiological risk.

    Science.gov (United States)

    Martinez-Serrano, J Javier; Diez de Los Rios, Antonio

    2014-08-01

    The PET cyclotron at the Centre of Molecular Imaging of the Universidad de Malaga (CIMES) is a 16.5 MeV GE PETtrace cyclotron working at dual beam (40 μA beam). The cyclotron is dedicated mainly to F production. The F target has two thin circular foils composed of a metal alloy (Havar), that are highly activated by the proton beam and secondary neutrons. The main purpose of this study is to assess induced activity radiological risk derived from the Havar foils activation. Induced activity in Havar foils was estimated by two procedures. One consisted in estimating neutron and proton fluxes with MCNPX and using them as inputs in the activation code ACAB. Alternatively, given the regular periodicity of the irradiation cycles, an analytical expression was derived to estimate activity concentrations of activation products using production rates calculated with MCNPX. Large differences were found in the induced foil activities predicted by the two procedures. Therefore, an irradiated vacuum foil was measured with a Ge detector to analyze activity levels. Cobalt-58 (Co) and Co activities calculated with ACAB match well with measurements. Cobalt-60 (Co) activity estimated with the alternative method agrees acceptably with the measured activity, and Co activity is slightly overestimated. Cobalt-57 (Co) is the activation product of concern in the long term. The vacuum and window foils will be exempted in 3.3 y and 5.5 y, respectively, after replacement. Calculated effective dose with MCNPX and ICRP reference HML phantoms in the foils replacement operation is 0.34 mSv, and annual effective dose would be 2.1 mSv, which is below the annual limits.

  13. Fabrication of Natural Uranium UO2 Disks (Phase II): Texas A&M Work for Others Summary Document

    Energy Technology Data Exchange (ETDEWEB)

    Gerczak, Tyler J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Baldwin, Charles A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Schmidlin, Joshua E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Henry, Jr, John James [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-08-28

    The steps to fabricate natural UO2 disks for an irradiation campaign led by Texas A&M University are outlined. The process was initiated with stoichiometry adjustment of parent, U3O8 powder. The next stage of sample preparation involved exploratory pellet pressing and sintering to achieve the desired natural UO2 pellet densities. Ideal densities were achieved through the use of a bimodal powder size blend. The steps involved with disk fabrication are also presented, describing the coring and thinning process executed to achieve final dimensionality.

  14. A new species of Elasmia Möschler from New Mexico and Texas, and a new subspecies of Elasmia mandela (Druce from Texas and Oklahoma (Lepidoptera, Notodontidae, Nystaleinae

    Directory of Open Access Journals (Sweden)

    Eric Metzler

    2011-11-01

    Full Text Available Hippia packardii (Morrison and Hippia insularis (Grote are moved to the genus Elasmia Möschler as comb. n. Elasmia cave Metzler, sp. n. is described from New Mexico and Texas, and Elasmia mandela santaana Metzler & Knudson, ssp. n. is described from Texas and Oklahoma. A key to the species of Elasmia of southwestern U.S. is provided. Adult male and female moths of Elasmia from southwestern U.S. and their genitalia are illustrated.

  15. A micropulse monitor for control of cyclotron beams

    Science.gov (United States)

    Lind, D. A.; Peterson, R. J.; Da Silva, A. G.; Auler, L. T.; de Barros, S.

    1990-07-01

    A system using wall current monitors to observe the time structure of the individual beam current pulses of the Cyclotron Corp. CV28 cyclotron installed at the Instituto de Engenharia Nuclear of CNEN in Rio de Janeiro is described. The monitors are designed to give a faithful representation of the actual beam pulse, so the effects on the longitudinal phase space could be seen as the cyclotron parameters were changed. Beam pulses of width in the range of 1 to 4 ns and with a charge of 7 × 10-16 C or greater can be observed. With two units in the line transit times permit beam energy determination as well as charge distribution. For timing purposes a unit placed in front of a target is used to generate a start signal for time-of-flight measurements, and to monitor the effects of all parameters of the cyclotron tune. By measuring flight times in the beamlines of this machine, the energy for 28 MeV protons can be determined to about 50 keV and for the other available particles to about 30 keV.

  16. Low current performance of the Bern medical cyclotron down to the pA range

    Science.gov (United States)

    Auger, M.; Braccini, S.; Ereditato, A.; Nesteruk, K. P.; Scampoli, P.

    2015-09-01

    A medical cyclotron accelerating H- ions to 18 MeV is in operation at the Bern University Hospital (Inselspital). It is the commercial IBA 18/18 cyclotron equipped with a specifically conceived 6 m long external beam line ending in a separate bunker. This feature is unique for a hospital-based facility and makes it possible to conduct routine radioisotope production for PET diagnostics in parallel with multidisciplinary research activities, among which are novel particle detectors, radiation biophysics, radioprotection, radiochemistry and radiopharmacy developments. Several of these activities, such as radiobiology experiments for example, require low current beams down to the pA range, while medical cyclotrons are designed for high current operation above 10 μA. In this paper, we present the first results on the low current performance of a PET medical cyclotron obtained by ion source, radio-frequency and main coil tuning. With this method, stable beam currents down to (1.5+/- 0.5 ) pA were obtained and measured with a high-sensitivity Faraday cup located at the end of the beam transport line.

  17. The Texas Dental Association and advocacy: a TDA president's perspective.

    Science.gov (United States)

    Eggleston, Frank K; Jeske, Arthur H

    2008-08-01

    The TDA can take pride in the joint efforts of its leadership, its grassroots members, and its elected representatives in the middle of the decade of the 1990's. When asked about his legacy for the leadership of our organization, Dr. Eggleston emphatically states, "You have to act. You have to do the right thing even when you have critics and detractors." More recently, during his campaign for ADA President-elect, he constantly stressed the importance of our relationship with each other. Our relationship, in Dr. Eggleston's words now and during his TDA presidency, "is more important than all issues put together". As this brief retrospective illustrates, the issues faced by dentists and the TDA are never trivial and are always tied to the legislative process. Political advocacy by our association is, therefore, our first priority now, no less so than it was in the mid-1990's. As described in the recent "TDA Report Card" on our legislative agenda for the 80th Texas Legislature, our challenges continue unabated, but these challenges are answered, and in many cases, successfully overcome as a result of our advocacy efforts. Our need for constant involvement in the legislative process is perhaps best summarized by advice given to Dr. Eggleston by Senator (and oral surgeon) David Sibley at the 1995 TDA Annual Session. Senator Sibley complimented TDA on its achievements during the 1995 Texas legislative session, and added "but you've got to keep your garden weeded."

  18. Cyclotron laboratory of the Institute for Nuclear Research and Nuclear Energy

    Science.gov (United States)

    Tonev, D.; Goutev, N.; Georgiev, L. S.

    2016-06-01

    An accelerator laboratory is presently under construction in Sofia at the Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences. The laboratory will use a TR24 type of cyclotron, which provides a possibility to accelerate a proton beam with an energy of 15 to 24 MeV and current of up to 0.4 mA. An accelerator with such parameters allows to produce a large variety of radioisotopes for development of radiopharmaceuticals. The most common radioisotopes that could be produced with such a cyclotron are PET isotopes like: 11C, 13N, 15O, 18F, 124I, 64Cu, 68Ge/68Ga, and SPECT isotopes like: 123I, 111In, 67Ga, 57Co, 99m Tc. Our aim is to use the cyclotron facility for research in the fields of radiopharmacy, radiochemistry, radiobiology, nuclear physics, solid state physics, applied research, new materials and for education in all these fields including nuclear energy. The building of the laboratory will be constructed nearby the Institute for Nuclear Research and Nuclear Energy and the cyclotron together with all the equipment needed will be installed there.

  19. Hydrological extremes and their agricultural impacts under a changing climate in Texas

    Science.gov (United States)

    Lee, K.; Gao, H.; Huang, M.; Sheffield, J.

    2015-12-01

    With the changing climate, hydrologic extremes (such as floods, droughts, and heat waves) are becoming more frequent and intensified. Such changes in extreme events are expected to affect agricultural production and food supplies. This study focuses on the State of Texas, which has the largest farm area and the highest value of livestock production in the U.S. The objectives are two-fold: First, to investigate the climatic impact on the occurrence of future hydrologic extreme events; and second, to evaluate the effects of the future extremes on agricultural production. The Variable Infiltration Capacity (VIC) model, which is calibrated and validated over Texas river basins during the historical period, is employed for this study. The VIC model is forced by the statistically downscaled climate projections from the Coupled Model Intercomparison Project Phase 5 (CMIP5) model ensembles at a spatial resolution of 1/8°. The CMIP5 projections contain four different scenarios in terms of Representative Concentration Pathway (RCP) (i.e. 2.6, 4.5, 6.0 and 8.5 w/m2). To carry out the analysis, VIC outputs forced by the CMIP5 model scenarios over three 30-year periods (1970-1999, 2020-2049 and 2070-2099) are first evaluated to identify how the frequency and the extent of the extreme events will be altered in the ten Texas major river basins. The results suggest that a significant increase in the number of extreme events will occur starting in the first half of the 21st century in Texas. Then, the effects of the predicted hydrologic extreme events on the irrigation water demand are investigated. It is found that future changes in water demand vary by crop type and location, with an east-to-west gradient. The results are expected to contribute to future water management and planning in Texas.

  20. Experimental observation of acoustic emissions generated by a pulsed proton beam from a hospital-based clinical cyclotron.

    Science.gov (United States)

    Jones, Kevin C; Vander Stappen, François; Bawiec, Christopher R; Janssens, Guillaume; Lewin, Peter A; Prieels, Damien; Solberg, Timothy D; Sehgal, Chandra M; Avery, Stephen

    2015-12-01

    To measure the acoustic signal generated by a pulsed proton spill from a hospital-based clinical cyclotron. An electronic function generator modulated the IBA C230 isochronous cyclotron to create a pulsed proton beam. The acoustic emissions generated by the proton beam were measured in water using a hydrophone. The acoustic measurements were repeated with increasing proton current and increasing distance between detector and beam. The cyclotron generated proton spills with rise times of 18 μs and a maximum measured instantaneous proton current of 790 nA. Acoustic emissions generated by the proton energy deposition were measured to be on the order of mPa. The origin of the acoustic wave was identified as the proton beam based on the correlation between acoustic emission arrival time and distance between the hydrophone and proton beam. The acoustic frequency spectrum peaked at 10 kHz, and the acoustic pressure amplitude increased monotonically with increasing proton current. The authors report the first observation of acoustic emissions generated by a proton beam from a hospital-based clinical cyclotron. When modulated by an electronic function generator, the cyclotron is capable of creating proton spills with fast rise times (18 μs) and high instantaneous currents (790 nA). Measurements of the proton-generated acoustic emissions in a clinical setting may provide a method for in vivo proton range verification and patient monitoring.

  1. Imaging study of using radiopharmaceuticals labeled with cyclotron-produced 99mTc.

    Science.gov (United States)

    Hou, X; Tanguay, J; Vuckovic, M; Buckley, K; Schaffer, P; Bénard, F; Ruth, T J; Celler, A

    2016-12-07

    Cyclotron-produced 99mTc (CPTc) has been recognized as an attractive and practical substitution of reactor/generator based 99mTc. However, the small amount of 92-98Mo in the irradiation of enriched 100Mo could lead to the production of other radioactive technetium isotopes (Tc-impurities) which cannot be chemically separated. Thus, these impurities could contribute to patient dose and affect image quality. The potential radiation dose caused by these Tc-impurities produced using different targets, irradiation conditions, and corresponding to different injection times have been investigated, leading us to create dose-based limits of these parameters for producing clinically acceptable CPTc. However, image quality has been not considered. The aim of the present work is to provide a comprehensive and quantitative analysis of image quality for CPTc. The impact of Tc-impurities in CPTc on image resolution, background noise, and contrast is investigated by performing both Monte-Carlo simulations and phantom experiments. Various targets, irradiation, and acquisition conditions are employed for investigating the image-based limits of CPTc production parameters. Additionally, the relationship between patient dose and image quality of CPTc samples is studied. Only those samples which meet both dose- and image-based limits should be accepted in future clinical studies.

  2. Electromagnetic Cyclotron Waves in the Solar Wind: Wind Observation and Wave Dispersion Analysis

    Science.gov (United States)

    Jian, L. K.; Moya, P. S.; Vinas, A. F.; Stevens, M.

    2016-01-01

    Wind observed long-lasting electromagnetic cyclotron waves near the proton cyclotron frequency on 11 March 2005, in the descending part of a fast wind stream. Bi-Maxwellian velocity distributions are fitted for core protons, beam protons, and alpha-particles. Using the fitted plasma parameters we conduct kinetic linear dispersion analysis and find ion cyclotron and/or firehose instabilities grow in six of 10 wave intervals. After Doppler shift, some of the waves have frequency and polarization consistent with observation, thus may be correspondence to the cyclotron waves observed.

  3. The Texas Academy of Mathematics and Science: A 20-Year Perspective

    Science.gov (United States)

    Jones, Brent M.

    2011-01-01

    The Texas Academy of Mathematics and Science (TAMS) is a publicly financed, residential early college entrance institute at the University of North Texas at Denton. Created in 1987, TAMS enables high-achieving students planning STEM careers to complete their last 2 years of high school simultaneously with their first 2 years of college. Admission…

  4. One-electron quantum cyclotron (and implications for cold antihydrogen)

    CERN Document Server

    Gabrielse, G; Odom, B; D'Urso, B

    2001-01-01

    Quantum jumps between Fock states of a one-electron oscillator reveal the quantum limit of a cyclotron accelerator. The states live for seconds when spontaneous emission is inhibited by a factor of 140 within a cylindrical Penning trap cavity. Averaged over hours the oscillator is in thermal equilibrium with black-body photons in the cavity. At 80 mK, quantum jumps occur only when resonant microwave photons are introduced into the cavity, opening a route to improved measurements of the magnetic moments of the electron and positron. The temperature demonstrated is about 60 times lower than the 4.2 K temperature at which charged elementary particles were previously stored. Implications for the production of cold antihydrogen are discussed. (21 refs).

  5. Electron Cyclotron Resonance Heating of a High-Density Plasma

    DEFF Research Database (Denmark)

    Hansen, F. Ramskov

    1986-01-01

    Various schemes for electron cyclotron resonance heating of tokamak plasmas with the ratio of electron plasma frequency to electron cyclotron frequency, "»pe/^ce* larger than 1 on axis, are investigated. In particular, a mode conversion scheme is investigated using ordinary waves at the fundamental...

  6. Terahertz cyclotron resonance spectroscopy of an AlGaN/GaN heterostructure using a high-field pulsed magnet and an asynchronous optical sampling technique

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, B. F., E-mail: Ben.Spencer@manchester.ac.uk; Smith, W. F.; Hibberd, M. T.; Dawson, P.; Graham, D. M. [School of Physics and Astronomy and the Photon Science Institute, The University of Manchester, Manchester M13 9PL (United Kingdom); Beck, M.; Bartels, A. [Laser Quantum GmbH, Max-Stromeyer-Str. 116, 78467 Konstanz (Germany); Guiney, I.; Humphreys, C. J. [Department of Materials Science and Metallurgy, 27 Charles Babbage Road, University of Cambridge, Cambridge CB3 0FS (United Kingdom)

    2016-05-23

    The effective mass, sheet carrier concentration, and mobility of electrons within a two-dimensional electron gas in an AlGaN/GaN heterostructure were determined using a laboratory-based terahertz cyclotron resonance spectrometer. The ability to perform terahertz cyclotron resonance spectroscopy with magnetic fields of up to 31 T was enabled by combining a high-field pulsed magnet with a modified asynchronous optical sampling terahertz detection scheme. This scheme allowed around 100 transmitted terahertz waveforms to be recorded over the 14 ms magnetic field pulse duration. The sheet density and mobility were measured to be 8.0 × 10{sup 12 }cm{sup −2} and 9000 cm{sup 2} V{sup −1} s{sup −1} at 77 K. The in-plane electron effective mass at the band edge was determined to be 0.228 ± 0.002m{sub 0}.

  7. Texas urban triangle : creating a spatial decision support system for mobility policy and investments that shape the sustainable growth of Texas.

    Science.gov (United States)

    2010-11-01

    This project developed a GIS-based Spatial Decision Support System to help local, metropolitan, and state : jurisdictions and authorities in Texas understand the implications of transportation planning and : investment decisions, and plan appropriate...

  8. Neutron spectra due (13)N production in a PET cyclotron.

    Science.gov (United States)

    Benavente, J A; Vega-Carrillo, H R; Lacerda, M A S; Fonseca, T C F; Faria, F P; da Silva, T A

    2015-05-01

    Monte Carlo and experimental methods have been used to characterize the neutron radiation field around PET (Positron Emission Tomography) cyclotrons. In this work, the Monte Carlo code MCNPX was used to estimate the neutron spectra, the neutron fluence rates and the ambient dose equivalent (H*(10)) in seven locations around a PET cyclotron during (13)N production. In order to validate these calculations, H*(10) was measured in three sites and were compared with the calculated doses. All the spectra have two peaks, one above 0.1MeV due to the evaporation neutrons and another in the thermal region due to the room-return effects. Despite the relatively large difference between the measured and calculated H*(10) for one point, the agreement was considered good, compared with that obtained for (18)F production in a previous work. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Meet the aggies; internship experience at the Texas A&M University

    NARCIS (Netherlands)

    Shukla, A.

    2013-01-01

    “Welcome to the United States of America” the lines I had heard quite a few times in movies and sitcoms. Yet here I was listening to it, jet lagged and sleep deprived after roughly 24 hrs of flying, having just completed the immigration clearance at George Bush International Airport, Houston.

  10. Target development for diversified irradiations at a medical cyclotron.

    Science.gov (United States)

    Spellerberg, S; Scholten, B; Spahn, I; Bolten, W; Holzgreve, M; Coenen, H H; Qaim, S M

    2015-10-01

    The irradiation facility at an old medical cyclotron (Ep=17 MeV; Ed=10 MeV) was upgraded by extending the beam line and incorporation of solid state targetry. Tests performed to check the quality of the available beam are outlined. Results on nuclear data measurements and improvement of radiochemical separations are described. Using solid targets, with the proton beam falling at a slanting angle of 20°, a few radionuclides, e.g. (75)Se, (120)I, (124)I, etc. were produced with medium currents (up to 20 µA) in no-carrier-added form in quantities sufficient for local use. The extended irradiation facility has considerably enhanced the utility of the medical cyclotron. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Gamma ray facilities at the University of Maryland cyclotron. [data acquisition and radiation measurement

    Science.gov (United States)

    Hornyak, W. F.

    1978-01-01

    A special beam line was set up in a separate shielded experimental room to provide a low background station for gamma-ray measurements at the University of Maryland cyclotron. The transmitted beam leaving the target is gathered in by a magnetic quadrupole lens located 1.8 m further downstream and focused on a Faraday cup located on the far side of the 2.5 m thick concrete shielding wall of the experimental room. A software computer program permits timing information ot be obtained using the cyclotron beam fine structure as a time reference for the observed gamma-ray events. Measurements indicate a beam fine structure width of less than 1.2 nanoseconds repeated, for example, in the case of 140 MeV alpha particles every 90 nanoseconds. Twelve contiguous time channels of adjustable width may be set as desired with reference to the RF signal. This allows the creation of 12 separate 8192 channel analyzers.

  12. Optimizing C4+ and C5+ beams of the Kei2 electron cyclotron resonance ion source using a special gas-mixing technique

    NARCIS (Netherlands)

    Drentje, A. G.; Muramatsu, M.; Kitagawa, A.

    With the prototype electron cyclotron resonance ion source for the next carbon therapy facility in Japan a series of measurements has been performed in order (a) to find the best condition for producing high beam currents of C4+ ions, and (b) to study the effect of "special" gas mixing by using a

  13. Design and characterization of a 32-channel heterodyne radiometer for electron cyclotron emission measurements on experimental advanced superconducting tokamak.

    Science.gov (United States)

    Han, X; Liu, X; Liu, Y; Domier, C W; Luhmann, N C; Li, E Z; Hu, L Q; Gao, X

    2014-07-01

    A 32-channel heterodyne radiometer has been developed for the measurement of electron cyclotron emission (ECE) on the experimental advanced superconducting tokamak (EAST). This system collects X-mode ECE radiation spanning a frequency range of 104-168 GHz, where the frequency coverage corresponds to a full radial coverage for the case with a toroidal magnetic field of 2.3 T. The frequency range is equally spaced every 2 GHz from 105.1 to 167.1 GHz with an RF bandwidth of ~500 MHz and the video bandwidth can be switched among 50, 100, 200, and 400 kHz. Design objectives and characterization of the system are presented in this paper. Preliminary results for plasma operation are also presented.

  14. Realistic simulations of a cyclotron spiral inflector within a particle-in-cell framework

    Science.gov (United States)

    Winklehner, Daniel; Adelmann, Andreas; Gsell, Achim; Kaman, Tulin; Campo, Daniela

    2017-12-01

    We present an upgrade to the particle-in-cell ion beam simulation code opal that enables us to run highly realistic simulations of the spiral inflector system of a compact cyclotron. This upgrade includes a new geometry class and field solver that can handle the complicated boundary conditions posed by the electrode system in the central region of the cyclotron both in terms of particle termination, and calculation of self-fields. Results are benchmarked against the analytical solution of a coasting beam. As a practical example, the spiral inflector and the first revolution in a 1 MeV /amu test cyclotron, located at Best Cyclotron Systems, Inc., are modeled and compared to the simulation results. We find that opal can now handle arbitrary boundary geometries with relative ease. Simulated injection efficiencies and beam shape compare well with measured efficiencies and a preliminary measurement of the beam distribution after injection.

  15. Status of a compact electron cyclotron resonance ion source for National Institute of Radiological Sciences-930 cyclotron.

    Science.gov (United States)

    Hojo, S; Katagiri, K; Nakao, M; Sugiura, A; Muramatsu, M; Noda, A; Okada, T; Takahashi, Y; Komiyama, A; Honma, T; Noda, K

    2014-02-01

    The Kei-source is a compact electron cyclotron resonance ion source using only permanent magnets and a frequency of 10 GHz. It was developed at the National Institute of Radiological Sciences (NIRS) for producing C(4+) ions oriented for high-energy carbon therapy. It has also been used as an ion source for the NIRS-930 cyclotron. Its microwave band region for the traveling-wave-tube amplifier and maximum output power are 8-10 GHz and 350 W, respectively. Since 2006, it has provided various ion beams such as proton, deuteron, carbon, oxygen, and neon with sufficient intensity (200 μA for proton and deuteron, 50 μA for C(4+), for example) and good stability for radioisotope production, tests of radiation damage, and basic research experiments. Its horizontal and vertical emittances were measured using a screen monitor and waist-scan. The present paper reports the current status of the Kei-source.

  16. Status of a compact electron cyclotron resonance ion source for National Institute of Radiological Sciences-930 cyclotron

    Science.gov (United States)

    Hojo, S.; Katagiri, K.; Nakao, M.; Sugiura, A.; Muramatsu, M.; Noda, A.; Okada, T.; Takahashi, Y.; Komiyama, A.; Honma, T.; Noda, K.

    2014-02-01

    The Kei-source is a compact electron cyclotron resonance ion source using only permanent magnets and a frequency of 10 GHz. It was developed at the National Institute of Radiological Sciences (NIRS) for producing C4+ ions oriented for high-energy carbon therapy. It has also been used as an ion source for the NIRS-930 cyclotron. Its microwave band region for the traveling-wave-tube amplifier and maximum output power are 8-10 GHz and 350 W, respectively. Since 2006, it has provided various ion beams such as proton, deuteron, carbon, oxygen, and neon with sufficient intensity (200 μA for proton and deuteron, 50 μA for C4+, for example) and good stability for radioisotope production, tests of radiation damage, and basic research experiments. Its horizontal and vertical emittances were measured using a screen monitor and waist-scan. The present paper reports the current status of the Kei-source.

  17. Converting an AEG Cyclotron to H- Acceleration and Extraction

    Science.gov (United States)

    Ramsey, Fred; Carroll, Lewis; Rathmann, Tom; Huenges, Ernst; Bechtold, Matthias Mentler Volker

    2009-03-01

    Clinical Trials are under way to evaluate agents labeled with the nuclide 225Ac and its decay product 213Bi, in targeted alpha-immuno-therapy [1]. 225Ac can be produced on a medium-energy cyclotron via the nuclear reaction 226Ra(p,n)225Ac. To demonstrate proof-of-principle, a vintage AEG cyclotron, Model E33 [2], with an internal target, had been employed in a pilot production program at the Technical University of Munich (TUM). To enhance production capability and further support the clinical studies, the TUM facility has recently been refurbished and upgraded, adding a new external beam-line, automated target irradiation and transport systems, new laboratories, hot cells, etc. [3]. An improved high-power rotating target has been built and installed [4]. The AEG cyclotron itself has also been modified and upgraded to accelerate and extract H- ions. We have designed, built, and tested a new axial Penning-type ion source which is optimized for the production of H- ions. The ion source has continued to evolve through experiment and experience. Steady improvements in materials and mechanics have led to enhanced source stability, life-time, and H- production. We have also designed and built a precision H- charge-exchange beam-extraction system which is equipped with a vacuum lock. To fit within the tight mechanical constraint imposed by the narrow magnet gap, the system incorporates a novel chain-drive foil holder and foil-changer mechanism. The reconfigured cyclotron system has now been in operation for more than 1 year. Three long-duration target irradiations have been conducted. The most recent bombardment ran 160 continuous hours at a beam on target of ˜80 microamperes for a total yield of ˜70 milli-curies of 225Ac.

  18. 33 CFR 165.804 - Snake Island, Texas City, Texas; mooring and fleeting of vessels-safety zone.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Snake Island, Texas City, Texas... Guard District § 165.804 Snake Island, Texas City, Texas; mooring and fleeting of vessels—safety zone. (a) The following is a safety zone: (1) The west and northwest shores of Snake Island; (2) The...

  19. A Reference Handbook of the Texas Health Professions and their Support Personnel; The Health Professions in Texas.

    Science.gov (United States)

    Texas Nurses Association.

    The fields of dentistry, dietetics, medicine, medical technology, nursing, occupational therapy, pharmacy, physical therapy, and social work are defined in the handbook. The entrance requirements, educational institutions, and licensure regulations in Texas are treated for each major and allied support field. The functions or types of…

  20. RXTE Observations of the 1A 1118-61 in an Outburst, and the Discovery of a Cyclotron Line

    Science.gov (United States)

    Doroshenko, V.; Suchy, S.; Santangelo, A; Staubert, R.; Kreykenbohm, I.; Rothschild, R.; Pottschmidt, K.; Wilms, J.

    2010-01-01

    We present the analysis of RXTE monitoring data obtained during the January 2009 outburst of the hard X-ray transient IA 1118-61. Using these observations the broadband (3.5-120 keV) spectrum of the source was measured for the first time ever. We have found that the broadband continuum spectrum of the source is similar to other accreting pulsars and is well described by several conventionally used phenomenological models. We have discovered that regardless of the applied continuum model, a prominent broad absorption feature at approx. 55 keV is observed. We interpret this feature as a Cyclotron Resonance Scattering Feature (CRSF). The observed CRSF energy is one of the highest known and corresponds to a magnetic field of B approx. 4.8 x 10(exp 12) G in the scattering region. Furthermore, our data suggests an iron emission line presence, which was not reported previously for lA 1118-61 as well. Timing properties of the source, including a strong spin-up, were found to be similar to those observed by CGRO/BATSE during the previous outburst, however the broadband capabilities of RXTE reveal a more complicated energy dependency of the pulse-profile.

  1. Angiostrongylus cantonensis Meningitis and Myelitis, Texas, USA.

    Science.gov (United States)

    Al Hammoud, Roukaya; Nayes, Stacy L; Murphy, James R; Heresi, Gloria P; Butler, Ian J; Pérez, Norma

    2017-06-01

    Infection with Angiostrongylus cantonensis roundworms is endemic in Southeast Asia and the Pacific Basin. A. cantonensis meningitis and myelitis occurred in summer 2013 in a child with no history of travel outside of Texas, USA. Angiostrongyliasis is an emerging neurotropic helminthic disease in Texas and warrants increased awareness among healthcare providers.

  2. Physical trajectory profile data from glider Stommel deployed by Texas A&M University; Texas A&M University - College Station; Geochemical and Environmental Research Group in the Gulf of Mexico from 2016-08-05 to 2016-09-05 (NCEI Accession 0156568)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This deployment is to investigate conditions in the region of the Flower Garden Banks after a die-off was reported. The National Centers for Environmental...

  3. A Border vs. Nonborder Comparison of Food Environment, Poverty, and Ethnic Composition in Texas Urban Settings

    Directory of Open Access Journals (Sweden)

    Jennifer J Salilnas

    2015-04-01

    Full Text Available Purpose: The goal was to examine the relationship between the food environment and selected socioeconomic variables and ethnic/racial makeup in the eight largest urban settings in Texas so as to gain a better understanding of the relationships among Hispanic composition, poverty and urban foodscapes, comparing border to non-border urban environments. Methods: Census-tract level data on (a socioeconomic factors, like percentage below the poverty line and number of households on foodstamps, and (b ethnic variables, like percent of Mexican origin and percent foreign born, were obtained from the U.S. Census. Data at the census-tract level on the total number of healthy (e.g., supermarkets and less-healthy (e.g., fast food outlets food retailers were acquired from the CDC’s Modified Retail Food Environment Index (mRFEI. Variation among urban settings in terms of the relationship between mRFEI scores and socioeconomic and ethnic context was tested using a mixed-effect model, and linear regression was used to identify significant factors for each urban location. A jackknife variance estimate was used to account for clustering and autocorrelation of adjacent census tracts.Results: Average census-tract mRFEI scores exhibited comparatively small variation across Texas urban settings, while socioeconomic and ethnic factors varied significantly. The only covariates significantly associated with mRFEI score were percent foreign born and percent Mexican origin. Compared to the highest-population county (Harris, which incorporates most of Houston, the only counties that had significantly different mRFEI scores were Bexar, which is analogous to San Antonio (2.12 lower, El Paso (2.79 higher, and Neuces, which encompasses Corpus Christi (2.90 less. Significant interaction effects between mRFEI and percent foreign born (El Paso, Tarrant – Fort Worth, Travis – Austin, percent Mexican origin (Hidalgo – McAllen, El Paso, Tarrant, Travis, and percent living

  4. Symmetry Properties of Proton Velocity Distributions: a Vlasov Simulation Study of the Ion Cyclotron Instability

    Science.gov (United States)

    Araneda, J. A.; López, R. A.; Vinas, A. F.

    2014-12-01

    The ion cyclotron instability is driven by a sufficiently large proton temperature anisotropy, generating a spectrum of counterpropagating field-aligned ion cyclotron fluctuations. In this work, we use low-noise one-dimensional electromagnetic Vlasov simulations in a magnetized and collisionless plasma of fluid electrons and one ion species to study the evolution of proton velocity distributions during the thermal relaxation process. Special attention is given to deviations from initial bi-Maxwellian shapes.

  5. Mr Bikash Sinha, Director of SAHA & VECC and Prof. Rolf Heuer, Director general of CERN, sign a collaboration agreements between SAHA (Saha Institute of Nuclear Physics), VECC (Variable Energy Cyclotron Centre), India and CERN ISOLDE.

    CERN Multimedia

    Maximilien Brice

    2009-01-01

    Mr Bikash Sinha, Director of SAHA & VECC and Prof. Rolf Heuer, Director general of CERN, sign a collaboration agreements between SAHA (Saha Institute of Nuclear Physics), VECC (Variable Energy Cyclotron Centre), India and CERN ISOLDE.

  6. A new EMIS facility at the Tohoku University cyclotron

    Science.gov (United States)

    Fujioka, M.; Shinozuka, T.; Tanaka, E.; Arai, Y.; Hayashibe, S.; Ishimatsu, T.

    1981-07-01

    An EMIS facility has begun operation at one of the beam lines of a multipurpose cyclotron of K = 50 MeV. The separator is of a Scandinavian type of 55° deflection and 1500 mm dispersion, and is equipped with three beam-transport lines to which are connected a tape-transport system for ISOL study, a retardation system for implantation work and an optical spectrometer for surface analysis. The status and developments of this facility are reported here for the first time.

  7. Senior Centers and Nutritional Outcomes: A Texas Example.

    Science.gov (United States)

    Swan, James H; Severance, Jennifer J; Turner, Keith

    2016-01-01

    Healthy diet and weight control are important for elders and senior centers (SCs). The authors consider effects of SCs on attendee nutrition and health and efforts to improve diets and weight. Data derive from surveys in 2006 (N = 798) and 2007 (N = 742) at 21 multipurpose SCs in Tarrant County, Texas, supplemented with data from 2012 (N = 1,402). Measures included attendee agreement that SC meals improved nutrition, improved health, attempts to improve diets, and success in controlling weight. Cumulative and binary logistic regression methods were employed. SC attendance and social engagement explained agreement that SC meals improved nutrition and health but were not shown to predict changes in diet or weight control. Findings suggest success of SC programs, as well as physician recommendations, in influencing attendee nutritional behavior and perceptions of nutrition and health effects. Practice recommendations include SC collaborations with local health providers to promote attendee nutritional health.

  8. Magnetic Cyclotron Waves near the Proton Cyclotron Frequency in the Solar Wind: Wind and ACE Observations in 2005

    Science.gov (United States)

    Broiles, T. W.; Jian, L.; Stevens, M. L.; Gary, S. P.; Lepri, S. T.; Vinas, A. F.; Moya, P. S.; Alexander, R.

    2016-12-01

    Strong narrow-band electromagnetic waves near the proton cyclotron frequency (fpc) have been observed extensively in the solar wind throughout the inner heliosphere. They are transverse and near-circularly polarized, and propagate in directions quasi-parallel or anti-parallel to the magnetic field. Their frequency is a few times of fpc in the spacecraft frame and a fraction of fpc in the plasma frame after removing the Doppler shift effect. These waves are left-hand (LH) or right-hand (RH) polarized in the spacecraft frame with otherwise similar characteristics except LH ones appear more often and have higher wave power. Intrinsically they can be LH polarized Alfven-cyclotron waves or RH polarized magnetosonic waves. Through the assistance of audification, we have studied the long-lasting wave events near fpc in 2005 using the high-cadence magnetic field data and well-calibrated plasma data from the Wind mission. A mixture of temperature anisotropies for core protons, beam protons, and alpha particles, as well as proton beam drift are often found for selected events of extensive waves. The wave dispersion analysis using these ion moments indicate these waves are likely to be associated with unstable Alfven-cyclotron anisotropy instability or ion beam instability, and suggest there is a mixture of Alfven-cyclotron waves and magnetosonic waves in the solar wind. Using the conjunction of Wind and ACE spacecraft when they were within 50 Earth radii of each other, we study how often the two spacecraft observe the same waves and whether there is noticeable heating for heavy ions associated with these waves.

  9. Direct Technetium radiopharmaceuticals production using a 30MeV Cyclotron

    Science.gov (United States)

    Jalilian, AR.; Targholizadeh, H.; Raisali, GR.; Zandi, H.; Kamali Dehgan, M.

    2011-01-01

    Background and the purpose of the study Technetium-99m is the major radionuclide used in the world and mainly is provided by fission product. However extensive research has been conducted on the use of accelerators for production of 99mTc. This investigation reports the production of 99mTc radioisotope using cyclotrons and the preparation, quality control and biodistribution studies of four major Tc-radiopharmaceuticals. Methods The high purity molybdenum natural target (130 mg/cm2) was irradiated in a Cyclone 30 accelerator using 160 µA of 25 MeV proton beam energy for 1000 µA-h. After dissolution, the technetium radionuclides were extracted using methyl ethyl ketone (MEK) followed by preparation of Tc-MIBI, Tc-DTPA, Tc-DMSA and Tc-phytate as radiopharmaceutical samples. Results The results of quality controls and animal biodistribution studies showed successful production of Tc radionuclides (including 99mTc) in the bombarded target and subsequent labelling of the kit with Tc. Conclusion The developed high power Mo target if constructed using enriched 100Mo, could be a practical method for large-scale production of 99mTc and promising as an alternative to fission product 99Mo-99mTc generators for local applications near cyclotron facilities. PMID:22615656

  10. STRUCTURE OF THE FRESH ONION MARKET IN THE SPRING SEASON: A FOCUS ON TEXAS AND ITS COMPETITION

    OpenAIRE

    Fuller, Stephen W.; Capps, Oral, Jr.; Bello, Haruna; Shafer, Carl E.

    1991-01-01

    A structural model of the spring onion economy is developed to analyze forces affecting the onion-producing sector in Texas. Spring onion prices in Texas are influenced by own shipments, shipments from storage stocks, and variety. Texas's decline in market share is largely the result of expanded late summer (storage) onion production. A decline in the U.S. real tariff and a weakening of the real exchange rate (pesos/$) encouraged onion imports from Mexico during the study period. However, thi...

  11. Direct Technetium radiopharmaceuticals production using a 30MeV Cyclotron

    Directory of Open Access Journals (Sweden)

    M Kamali Dehgan

    2011-07-01

    Full Text Available Background and purpose of the study: Technetium-99m is the major radionuclide used in the world and mainly is provided by fission product. However extensive research has been conducted on the use of accelerators for production of 99mTc. This investigation reports the production of 99mTc radioisotope using cyclotrons followed by the preparation, quality control and biodistribution studies of four major Tc-radiopharmaceuticals. Methods: The high purity molybdenum natural target (130mg/cm2 was irradiated in a Cyclone 30 accelerator using 160 µA of 25 MeV proton beam energy for 1000 µA-h. After dissolution, the technetium radionuclides were extracted using methyl ethyl ketone (MEK followed by preparation of Tc-MIBI, Tc-DTPA, Tc-DMSA and Tc-phytate as radiopharmaceutical samples. Results: The results of quality controls and animal biodistribution studies showed successful production of Tc radionuclides (including 99mTc in the bombarded target and subsequent labelling of the kit with Tc. Conclusion: The developed high power Mo target if constructed using enriched 100Mo, could be a practical method for large-scale production of 99mTc and promising as an alternative to fission product 99Mo-99mTc generators for local applications near cyclotron facilities.

  12. Physical trajectory profile data from glider Sverdrup deployed by Texas A&M University; Texas A&M University - College Station; Geochemical and Environmental Research Group in the Gulf of Mexico from 2017-09-02 to 2017-09-06 (NCEI Accession 0166617)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Qantifying mixing parameters and processes of the northern Gulf of Mexico using gliders. The National Centers for Environmental Information (NCEI) received the data...

  13. Physical trajectory profile data from glider Howdy deployed by Texas A&M University; Texas A&M University - College Station; Geochemical and Environmental Research Group in the Coastal Waters of Gulf of Mexico from 2016-09-02 to 2016-09-05 (NCEI Accession 0156591)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This deployment is to investigate mixing and microstructure in the Northern Gulf of Mexico. The National Centers for Environmental Information (NCEI) received the...

  14. Two-slope soft X-ray spectra observed in experiments on electron cyclotron resonance plasma heating in the L-2M stellarator

    Science.gov (United States)

    Meshcheryakov, A. I.; Vafin, I. Yu.; Grishina, I. A.; Letunov, A. A.; Tereshchenko, M. A.

    2017-06-01

    In experiments on the generation and electron cyclotron resonance heating (ECRH) of plasma in the L-2M stellarator, non-Maxwellian two-slope soft X-ray (SXR) spectra were observed. The temperatures of the thermal and epithermal components of the spectra were measured as functions of the heating power and plasma density. A hypothesis based on the experimental results is suggested to explain the formation mechanism of two-slope SXR spectra in the ECRH experiments at the L-2M stellarator. The measured SXR spectra are compared with the results of numerical simulations.

  15. Influence of injection beam emittance on beam transmission efficiency in a cyclotron.

    Science.gov (United States)

    Kurashima, Satoshi; Kashiwagi, Hirotsugu; Miyawaki, Nobumasa; Yoshida, Ken-Ichi; Okumura, Susumu

    2014-02-01

    The JAEA AVF cyclotron accelerates various kinds of high-energy ion beams for research in biotechnology and materials science. Beam intensities of an ion species of the order of 10(-9)-10(-6) ampere are often required for various experiments performed sequentially over a day. To provide ion beams with sufficient intensity and stability, an operator has to retune an ion source in a short time. However, the beam intensity downstream of the cyclotron rarely increases in proportion to the intensity at the ion source. To understand the cause of this beam behavior, transmission efficiencies of a (12)C(5+) beam from an electron cyclotron resonance ion source to the cyclotron were measured for various conditions of the ion source. Moreover, a feasible region for acceleration in the emittance of the injection beam was clarified using a transverse-acceptance measuring system. We confirmed that the beam emittance and profile were changed depending on the condition of the ion source and that matching between the beam emittance and the acceptance of the cyclotron was degraded. However, after fine-tuning to improve the matching, beam intensity downstream of the cyclotron increased.

  16. Physical trajectory profile data from glider Revellie deployed by Texas A&M University; Texas A&M University - College Station; Geochemical and Environmental Research Group in the Coastal Waters of Gulf of Mexico from 2016-06-29 to 2016-07-15 (NCEI Accession 0156372)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This deployment is to investigate hypoxia in the Northern Gulf of Mexico. The National Centers for Environmental Information (NCEI) received the data in this...

  17. Physical trajectory profile data from glider Howdy deployed by Texas A&M University; Texas A&M University - College Station; Geochemical and Environmental Research Group in the Coastal Waters of Gulf of Mexico from 2016-06-30 to 2016-07-14 (NCEI Accession 0156371)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This deployment is to investigate hypoxia in the Northern Gulf of Mexico. The National Centers for Environmental Information (NCEI) received the data in this...

  18. 10 GHz ECRIS for Warsaw Cyclotron

    CERN Document Server

    Sudlitz, K

    1999-01-01

    Cusp type, 10 GHz ECRIS has been built and tested earlier. For obtaining intensive beams, more relevant for cyclotron, cusp geometry has been replaced by hexapole. Discharge chamber (stainless steel, 50 mm diameter, 250 mm long) is an extension of a coaxial line, feeding RF (9,6 GHz, up to 200 W) to the plasma. The NdFeB hexapole (0,52 T on the surface) has been used. The axial magnetic field is created by water cooled coils. The axial injection line dedicated to K160 isochronous heavy ion cyclotron has been constructed. The line consists of Glaser lenses, double focusing magnet, solenoid and mirror type inflector. The system provides sufficient transmission of the beam from ECR ion source to the firsts orbits of the cyclotron for m/q ranging from 7 to 2. After successful initial tests which were done in July 1997 the ECRIS serves as an external source for Warsaw Cyclotron.

  19. [Proceedings of the 5th Symposium on Mesozoic and Cenozoic Decapod Crustaceans, Krakow, Poland, 2013: A tribute to Pál Mihály Müller / R.H.B. Fraaije, M. Hyžný, J.W.M. Jagt, M. Krobicki & B.W.M. van Bakel (eds.)]: Some decapods (Crustacea; Brachyura and Stomatopoda) from the Pleistocene Beaumont Formation of Galveston, Texas

    NARCIS (Netherlands)

    Collins, J.S.H.; Garvie, C.L.; Mellish, C.J.T.

    2014-01-01

    Seven species of crab and an indeterminate stomatopod are recorded from the Pleistocene Beaumont Formation of Galveston Island, Texas. Of these, Hepatus pauli sp. nov., plus the extant Persephona aquilonaris and Callinectes danae are recorded as fossils for the first time, whereas the modern

  20. High-harmonic electron bunching in the field of a signal wave and the use of this effect in cyclotron masers with frequency multiplication

    Directory of Open Access Journals (Sweden)

    I. V. Bandurkin

    2005-01-01

    Full Text Available A method of organizing electron-wave interaction at the multiplied frequency of the signal wave is proposed. This type of electron-wave interaction provides multiplied-frequency electron bunching, which leads to formation of an intense harmonic of the electron current at a selected multiplied frequency of the signal wave. This effect is attractive for the use in klystron-type cyclotron masers with frequency multiplication as a way to increase the output frequency and improve the selectivity.

  1. Electrostatic ion cyclotron waves in a plasma with an ion beam and counterstreaming bulk electrons - Waves in the zero-frequency band. [in aurora

    Science.gov (United States)

    Singh, N.; Conrad, J. R.; Schunk, R. W.

    1985-01-01

    A common feature of the auroral plasma in the region above field-aligned (parallel) potential drops are electrostatic hydrogen cyclotron (EHC) waves. The present paper has the objective to show that wave excitation in the zero-frequency band can occur when the ion beams and the current-carrying bulk electrons counterstream. The instability mechanism involves the Landau interaction of the slow (negative energy) ion-beam-cyclotron waves with the drifting electrons and also with the target (background) ions. Only the latter resonant interaction between the beam and the target ions was considered by Okuda and Nishikawa (1984). In this study, it is shown that an electron drift makes an additional unstable contribution to the waves in the zero-frequency band, including those discussed by Okuda and Nishikawa.

  2. Quantitative assessment of Naegleria fowleri and Escherichia coli concentrations within a Texas reservoir.

    Science.gov (United States)

    Painter, Stephanie M; Pfau, Russell S; Brady, Jeff A; McFarland, Anne M S

    2013-06-01

    Previous presence/absence studies have indicated a correlation between the presence of the pathogenic amoeba Naegleria fowleri and the presence of bacteria, such as the fecal indicator Escherichia coli, in environmental surface waters. The objective of this study was to use quantitative real-time polymerase chain reaction (qPCR) methodologies to measure N. fowleri and E. coli concentrations within a Texas reservoir in late summer, and to determine if concentrations of N. fowleri and E. coli were statistically correlated. N. fowleri was detected in water samples from 67% of the reservoir sites tested, with concentrations ranging up to an estimated 26 CE (cell equivalents)/100 mL. E. coli was detected in water samples from 60% of the reservoir sites tested, with concentrations ranging up to 427 CE/100 mL. In this study, E. coli concentrations were not indicative of N. fowleri concentrations.

  3. THE TRUE IDENTITY OF COPELAND'S AQUATIC SCUTTLE FLY (DIPTERA: PHORIDAE) FROM INDIANA AND RECOGNITION OF A SIBLING SPECIES FROM TEXAS

    Science.gov (United States)

    Disney, R. Henry L.; Copeland, Robert S.; Murrell, Ebony

    2012-01-01

    Among the insects reported by Copeland (1989) breeding in the waters retained by treeholes in Indiana was a scuttle fly identified by W. H. Robinson as Megaselia scalaris (Loew). It is here reported that in fact this fly, along with fresh material from Illinois and Missouri, is M. imitatrix Borgmeier, whose type series was from Puerto Rico. An aquatic species reported from Texas is recognized as a sibling species of M. imitatrix and is named M. hansonix Disney, sp. nov. A single female from Brazil represents a third species of this complex, thus raising doubts about the identity of specimens from Brazil attributed to M. imitatrix by Benton and Claugher (2000). PMID:22879679

  4. Forests of east Texas, 2015

    Science.gov (United States)

    Kerry J.W. Dooley

    2017-01-01

    This resource update provides an overview of forest resources in east Texas based on an inventory conducted by the U.S. Forest Service, Forest Inventory and Analysis (FIA) program at the Southern Research Station (SRS) in cooperation with Texas A&M Forest Service. The 254 counties of Texas are consolidated into seven FIA survey units—Southeast (unit 1),...

  5. Discovery and modelling of a flattening of the positive cyclotron line/luminosity relation in GX 304-1 with RXTE

    Science.gov (United States)

    Rothschild, Richard E.; Kühnel, Matthias; Pottschmidt, Katja; Hemphill, Paul; Postnov, Konstantin; Gornostaev, Mikhail; Shakura, Nikolai; Fürst, Felix; Wilms, Jörn; Staubert, Rüdiger; Klochkov, Dmitry

    2017-04-01

    The Rossi X-ray Timing Explorer (RXTE) observed four outbursts of the accreting X-ray binary transient source, GX 304-1 in 2010 and 2011. We present results of detailed 3-100 keV spectral analysis of 69 separate observations, and report a positive correlation between cyclotron line parameters, as well as other spectral parameters, with power-law flux. The cyclotron line energy, width and depth versus flux, and thus luminosity, correlations show a flattening of the relationships with increasing luminosity, which are well described by quasi-spherical or disc accretion that yield the surface magnetic field to be ˜5 × 1012 Gauss. Since HEXTE (High Energy X-ray Timing Experiment) cluster A was fixed aligned with the Proportional Counter Array field of view and cluster B was fixed viewing a background region 1.5° off of the source direction during these observations near the end of the RXTE mission, the cluster A background was estimated from cluster B events using HEXTEBACKEST. This made possible the detection of the ˜55 keV cyclotron line and an accurate measurement of the continuum. Correlations of all spectral parameters with the primary 2-10 keV power-law flux reveal it to be the primary driver of the spectral shape. The accretion is found to be in the collisionless shock braking regime.

  6. Gaseous Oxidized Mercury Dry Deposition Measurements in the Southwestern USA: A Comparison between Texas, Eastern Oklahoma, and the Four Corners Area

    Directory of Open Access Journals (Sweden)

    Mark E. Sather

    2014-01-01

    Full Text Available Gaseous oxidized mercury (GOM dry deposition measurements using aerodynamic surrogate surface passive samplers were collected in central and eastern Texas and eastern Oklahoma, from September 2011 to September 2012. The purpose of this study was to provide an initial characterization of the magnitude and spatial extent of ambient GOM dry deposition in central and eastern Texas for a 12-month period which contained statistically average annual results for precipitation totals, temperature, and wind speed. The research objective was to investigate GOM dry deposition in areas of Texas impacted by emissions from coal-fired utility boilers and compare it with GOM dry deposition measurements previously observed in eastern Oklahoma and the Four Corners area. Annual GOM dry deposition rate estimates were relatively low in Texas, ranging from 0.1 to 0.3 ng/m2h at the four Texas monitoring sites, similar to the 0.2 ng/m2h annual GOM dry deposition rate estimate recorded at the eastern Oklahoma monitoring site. The Texas and eastern Oklahoma annual GOM dry deposition rate estimates were at least four times lower than the highest annual GOM dry deposition rate estimate previously measured in the more arid bordering western states of New Mexico and Colorado in the Four Corners area.

  7. A new RF system for a rejuvenated Synchro-cyclotron

    CERN Multimedia

    1975-01-01

    The Synchro-cyclotron is shown here shortly after the completion of the improvement programme, which left the steel magnet yoke as almost the only remaining component of the original machine. On the left can be seen the rotary condenser which produces the frequency modulation required for the acceleration (one of a pair available -in this instance ROTCO II). (see photo 7506015)

  8. Pathways to the Geosciences through 2YR Community Colleges: A Strategic Recruitment Approach being used at Texas A&M University

    Science.gov (United States)

    Houser, C.; Nunez, J.; Miller, K. C.

    2016-12-01

    Department and college operating budgets are increasingly tide to enrollment and student credit hour production, which requires geoscience programs to develop strategic recruitment programs to ensure long-term stability, but also to increase institutional support. There is evidence that proactive high school recruitment programs are successful in engaging students in the geosciences, particularly those that involve the parents, but these programs typically have relatively low-yields and are relatively expensive. This means that increased enrollment of undergraduates in geosciences programs and participation by under-represented groups depends on innovative and effective recruitment and retention practices. The College of Geosciences at Texas A&M University has recently developed a Pathways to the Geosciences program that facilitates the transfer of students from 2-year institutions by providing direction to students interested in the geosciences from one of our partner institutions: Blinn College, Lee College, Houston Community College, San Jacinto College and Lone Star College. Each of the partner institutions offer disciplinary majors related to the geosciences, providing a gateway for students to discover and consider the geosciences starting in their freshman year. The guided pathways provide much needed direction without restricting options and allow students to see connections between courses and their career goals. In its first year, the Pathways to the Geosciences program has resulted in a significant increase in transfer applications and admissions from the partner institutions by 74% and 107% respectively. The program has been successful because we have been proactive in helping students at the partner institutions find the information they need to effectively transfer to a 4-year program. The increase in applications is evidence that students from our partner institutions are being intentional in following a pathway to a major in the College of

  9. Ion cyclotron emission from fusion-born ions in large tokamak plasmas: a brief review from JET and TFTR to ITER

    CERN Document Server

    Dendy, R O

    2014-01-01

    Ion cyclotron emission (ICE) was the first collective radiative instability, driven by confined fusion-born ions, observed from deuterium-tritium plasmas in JET and TFTR. ICE comprises strongly suprathermal emission, which has spectral peaks at multiple ion cyclotron harmonic frequencies as evaluated at the outer mid-plane edge of tokamak plasmas. The measured intensity of ICE spectral peaks scaled linearly with measured fusion reactivity in JET. In other large tokamak plasmas, ICE is currently used as an indicator of fast ions physics. The excitation mechanism for ICE is the magnetoacoustic cyclotron instability (MCI); in the case of JET and TFTR, the MCI is driven by a set of centrally born fusion products, lying just inside the trapped-passing boundary in velocity space, whose drift orbits make large radial excursions to the outer mid-plane edge. Diagnostic exploitation of ICE in future experiments therefore rests in part on deep understanding of the MCI, and recent advances in computational plasma physics...

  10. Coupling of electrostatic ion cyclotron and ion acoustic waves in the solar wind

    Energy Technology Data Exchange (ETDEWEB)

    Sreeraj, T., E-mail: sreerajt13@iigs.iigm.res.in [Indian Institute of Geomagnetism, Navi Mumbai (India); Singh, S. V., E-mail: satyavir@iigs.iigm.res.in; Lakhina, G. S., E-mail: gslakhina@gmail.com [Indian Institute of Geomagnetism, Navi Mumbai (India); University of the Western Cape, Bellville 7535, Capetown (South Africa)

    2016-08-15

    The coupling of electrostatic ion cyclotron and ion acoustic waves is examined in three component magnetized plasma consisting of electrons, protons, and alpha particles. In the theoretical model relevant to solar wind plasma, electrons are assumed to be superthermal with kappa distribution and protons as well as alpha particles follow the fluid dynamical equations. A general linear dispersion relation is derived for such a plasma system which is analyzed both analytically and numerically. For parallel propagation, electrostatic ion cyclotron (proton and helium cyclotron) and ion acoustic (slow and fast) modes are decoupled. For oblique propagation, coupling between the cyclotron and acoustic modes occurs. Furthermore, when the angle of propagation is increased, the separation between acoustic and cyclotron modes increases which is an indication of weaker coupling at large angle of propagation. For perpendicular propagation, only cyclotron modes are observed. The effect of various parameters such as number density and temperature of alpha particles and superthermality on dispersion characteristics is examined in details. The coupling between various modes occurs for small values of wavenumber.

  11. Development and Implementation of Sargassum Early Advisory System (SEAS): Phase One By Brandon N. Hill Ocean and Coastal Resources bhill8901@yahoo.com Robert K. Webster Ph.D. Candidate, Marine Sciences Department captrwebster@aol.com Texas A & M University at Galveston P.O. Box 1675 Galveston, Texas 77553

    Science.gov (United States)

    Hill, B. N.; Webster, R.; Frazier, J.; Linton, T.

    2013-12-01

    Abstract: Sargassum is a crucial aspect of many oceanic and coastal environments. However, it can inundate a coast if the conditions permit excessive growth and landings. In nature this is not a detriment to the beaches, but actually serves to reduce erosion and provide nutrients. When beaches are relied upon to support the tourism industry abnormally excessive Sargassum landings can become an impediment. This creates a struggle between the environmental good of the beach and the economic good of the tourism industry. The Sargassum Early Advisory System (SEAS) Phase One focuses on increasing the efficiency of the current beach management practices. Phase One begins with the effort to employ NASA Landsat images as early warning devices of Sargassum's impending landfall. Oceanic currents as well as coastal wind patterns are hypothesized to be the primary drivers of Sargassum. The Hybrid Coordinate Ocean Model (HYCOM) as well as the Texas Automated Buoy System (TABS), Weatherbuoy, and beach cameras are used to receive real time data as well as future predictions to allow for the creation of accurate macroalgae forecasts. Landsat imagery has a sufficient resolution that slicks created by the Sargassum's disruption of the water surface can be differentiated. The Landsat's RGB array allows it to identify large Sargassum mats by a distinct green glow. The SEAS Team has created a 555 km X 516 km swath of monitoring that provides two to three week notices of eminent Sargasssum landfall. The remote sensing data is crosschecked with ground-truthing via mounted beach cameras and boating contacts. The SEAS Team creates advisories that are sent out to local beach managers and other stakeholders. These advisories allow for the beach managers to more efficiently allocate resources. If Sargassum is not observed in the Landsat images then beach managers are able to scale back the workforce and equipment committed to removing the Sargassum from the beach. If an excess of Sargassum is

  12. Cyclotron facilities in Brazil: Current status and licensing aspects

    Energy Technology Data Exchange (ETDEWEB)

    Facure, A.; Carvalho, S.M.; Di Prinzio, R.; Silveira, C.S.; Gasparian, P.B.R.; Franca, W.F., E-mail: facure@cnen.gov.br [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro, RJ (Brazil)

    2017-09-01

    Positron Emission Tomography (PET) is a highly sensitive and accurate nuclear medicine imaging technology but the major problem of this technique is the use of radioisotopes with short half-life, less than two hours. The production and selling of short half-life radioisotopes used to be monopoly of the Brazilian Government. In 2006, a Constitutional Amendment revoked the state monopoly due to the need for the use of short half-life radioisotopes in nuclear medicine centers very far from the government production facilities. The aim of this study is to describe the current status of short half-life radioisotopes production in Brazil and discuss some licensing process. In Brazil, as has been occurring worldwide, the number of nuclear medicine centers is increasing. Currently there are 123 services performing PET scans in Brazil. There are 14 cyclotrons operating in Brazil. The type of licensing process conducted in Brazil does not take into account the population density of each state, with a free competition model being adopted. Because of this there is a lot of equipment concentrated in the Southeast and no cyclotrons operating in the Northern part of the country. One of the biggest obstacles during the licensing process is the designation of qualified personnel as operation workers and radiation safety officers. The number of cyclotron accelerators and PET/CT equipment increased in recent years. However, a number of external factors such as the distance from the nuclear medicine centers, and qualified personnel have proved crucial for the economic viability of this type of facility. (author)

  13. The ethics of the Texas death penalty and its impact on a prolonged appeals process.

    Science.gov (United States)

    Pearlman, T

    1998-01-01

    Society remains sharply divided as to the deterrent value of capital punishment. Following the reintroduction of the death penalty in the United States, Texas law mandates the affirmative predictability of future dangerousness beyond a reasonable doubt before a jury can impose the ultimate penalty for capital murder. The validity of prediction of dangerousness has been challenged in three Texas landmark cases before the U.S. Supreme Court. The case of Karla Faye Tucker highlights the moral controversy that occurs when execution follows an appeals process stretching over more than a decade, during which time personality growth and the effects of prison rehabilitation may have eliminated or curbed criminal tendencies.

  14. Practical experience and challenges in the operation of medical cyclotron.

    Science.gov (United States)

    Kumar, Rajeev; Sonkawade, Rajendra G; Pandey, Anil K; Tripathi, Madhavi; Damle, Nishikant A; Kumar, Praveen; Bal, Chandra S

    2017-01-01

    The aim of this article was to share 10 years of operational experience of medical cyclotron and to provide working knowledge on the same. This experience has helped us gain working knowledge on cyclotron operation with practical points, which may help in improving F yield, minimizing the breakdown time, and help in the prevention of the occurrence of unusual events. Our facility has a self-shielded radioisotope delivery system eclipse 111 medical cyclotron with an 11 MeV proton beam in use for the past 10 years to produce positron emitters - namely, F, N, and F-2 gas - for PET imaging. During F production, we have followed a set protocol comprising the following: monitoring target pressure, rinsing the target with O water just immediately after bombardment, ion source feedback, radiofrequency (RF) feedback, and recording any unusual events that occurred during the operation. Besides this, enrichment of O water, target volume, target current, energy of the beam, variation in argon pressure on the target, bombardment duration, target status (new or old target or total number of previous bombardments on the same target), status of the delivery lines from target to the radiochemistry module (old or new) were also recorded. Rinsing with O water immediately after bombardment increases the life of the target and delivery line. The frequent problems encountered were with the ion source, RF, and target foil rupture. These problems were solved by rebuilding the ion source, changing the fuse of RF, and rebuilding the target. F yield can be increased by rinsing with O water immediately after bombardment. The effect of target leak - that is, rupture of vacuum window - can be avoided by immediate stoppage of bombardment.

  15. Oceanographic data from CTD casts from as part of the Texas-Louisiana Shelf Circulation and Transport Processes Study (LATEX PART A) from 01 May 1992 to 08 May 1992 (NODC Accession 9200259)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Oceanographic data from CTD casts from from 01 May 1992 to 08 May 1992. Data were collected by Texas A&M Universtiy (TAMU) as part of the Texas-Louisiana Shelf...

  16. Assessing Heat-to-Heat Variations Affecting Mechanism Based Modeling of Hydrogen Environment Cracking (HEAC) in High Strength Alloys for Marine Applications: Monel K-500

    Science.gov (United States)

    2016-01-28

    shafts, oil-well tools and instruments, surgical blades and scrapers, springs, valve trim, fasteners, and marine propeller shafts. These Ni-based...34Assessing Heat-to-Heat Variations Affecting Mechanism Based Modeling of Hydrogen Environment Cracking (HEAC) in High Strength Alloys for Marine ...Environment Cracking (HEAC) in High Strength Alloys for Marine Applications: Monel K-500 5a. CONTRACT NUMBER N00014-12-1-0506 5b. GRANT NUMBER N/A 5c

  17. Compensation for Overloads and Summer Employment: A Survey of Current Practice in Texas.

    Science.gov (United States)

    Hardy, James C.

    A survey was sent to 58 chief academic officers to gain information about compensation for instructional overloads and summer employment at public and private Texas colleges and universities. Responses were received from 42 institutions. Only two indicated that their institutions did not have a uniform policy guiding summer compensation amounts.…

  18. Whistler-cyclotron spontaneous fluctuations as a proxy to identify thermal and non-thermal electrons in the solar wind

    Science.gov (United States)

    Moya, P. S.; Vinas, A. F.; Navarro, R.; Araneda, J. A.

    2014-12-01

    Observed electron velocity distributions in the solar wind exhibit a variety of non-thermal features which deviate from thermal equilibrium, in the form of temperature anisotropies, suprathermal tails, and field aligned beams. The state close to thermal equilibrium and its departure from it provides a source for spontaneous emissions of electromagnetic fluctuations as for example the whistler cyclotron waves at electron scales. Here we present a comparative analysis of these fluctuations based upon anisotropic plasma modeled with thermal and non-thermal particle distributions. The analysis presented here considers the second-order theory of fluctuations and the dispersion relation of weakly transverse fluctuations, with wave vectors parallel to the uniform background magnetic field, in a finite temperature isotropic thermal bi-Maxwellian and non-thermal Tsallis-kappa-like magnetized electron-proton plasma. Dispersion analysis and stability thresholds are derived for these non-thermal distributions and compared with similar results obtained from PIC simulations using plasma and field parameters relevant to the solar wind environments. Our results indicate that there is a strong dependence between the shape of the velocity distribution function and the topological regions in the frequency-wave number plane in which the spontaneous fluctuations emerge. In the case of non-thermal plasmas there is an enhancement of the fluctuations level due to the effective higher-temperature effects and the excess of suprathermal particles. This feature may be used proxy to identify the nature of electron populations in space plasmas when high resolution particle instruments are not available.

  19. Water supply and needs for West Texas

    Science.gov (United States)

    This presentation focused on the water supplies and needs of West Texas, Texas High Plains. Groundwater is the most commonly used water resources on the Texas High Plains, with withdrawals from the Ogallala Aquifer dominating. The saturation thickness of the Ogallala Aquifer in Texas is such that t...

  20. Teachers and Teaching Conditions in Rural Texas: Policy Brief

    Science.gov (United States)

    Jimerson, Lorna

    2004-01-01

    Over four milliion children go to public schools in Texas; of these, almost half a million (474,000) students attend school in rural areas. Thirty-six percent of rural Texas students are members of a minority group, 46% are poor, and more than 31,000 students in rural Texas do not speak English well. These are Texas-style large numbers that begin…

  1. Effective production of ⁶⁵Zn with a PET cyclotron.

    Science.gov (United States)

    Lucconi, G; Cicoria, G; Pancaldi, D; Malizia, C; Marengo, M

    2012-08-01

    Cyclotrons dedicated to the production of PET radiopharmaceuticals for clinical use can be a resource also for research in other fields of science. In the present study we assessed the feasibility of (65)Zn production via the (65)Cu(p,n)(65)Zn reaction using a 16.5 MeV GE-PETtrace biomedical cyclotron. The radioisotope (65)Zn (t(1/2)=244.26 zd; decay mode: EC 98.3%, β(+) 1.7%) has a wide range of applications, especially in botany and agriculture; its long half life allows storage and delivery to research centers without a cyclotron on site. Natural copper foils (thickness: 100 μm; purity: >99.9%) were irradiated in a solid target station developed in our institution. The EXFOR and IAEA cross sections databases were carefully studied to optimize the irradiation setup in order to maximize the yield of the radionuclide of interest and minimize the production of isotopic impurities. We performed production runs at 20 μA for 30 min. Activity was measured using a calibrated HPGe gamma ray detector and an ionization chamber radionuclide activity meter. These measures showed the presence of two main contaminants: (63)Zn (t(1/2)=38.47 min) and (64)Cu (t(1/2)=12.7h); we produced (65)Zn with a saturation yield of (1.06 ± 0.07) GBq/μA (E(p)=12.65→10.48 MeV). The irradiated target was dissolved in 1 ml of 6N HNO(3) at the temperature of 90°C and then purified through anion exchange chromatography with BIO RAD AG 1×8 resin. The radionuclidic purity of the final solution of (65)Zn in HCl 0.005 N, expressed in activity, resulted superior to (99.921 ± 0.003) %. Copyright © 2012. Published by Elsevier Ltd.

  2. A Brief Sampling of West Texas Teacher Attitudes Toward Southwest Spanish and English Language Varieties

    Science.gov (United States)

    MacIntosh, Roderick; Ornstein, Jacob

    1974-01-01

    A questionnaire was administered to twenty-five teachers of the El Paso, Texas, area to determine their attitudes toward the Spanish and English spoken in the area. Most viewed the language as a "border slang" not equivalent to correct English or Spanish. (CK)

  3. Radiologic assessment of a self-shield with boron-containing water for a compact medical cyclotron.

    Science.gov (United States)

    Horitsugi, Genki; Fujibuchi, Toshioh; Yamaguchi, Ichiro; Eto, Akihisa; Iwamoto, Yasuo; Hashimoto, Hiromi; Hamada, Seiki; Obara, Satoshi; Watanabe, Hiroshi; Hatazawa, Jun

    2012-07-01

    The cyclotron at our hospital has a self-shield of boron-containing water. The amount of induced radioactivity in the boron-containing water shield of a compact medical cyclotron has not yet been reported. In this study, we measured the photon and neutron dose rates outside the self-shield during cyclotron operation. We estimated the induced radioactivities of the boron-containing water used for the self-shield and then measured them. We estimated the activation of concrete outside the self-shield in the cyclotron laboratory. The thermal neutron flux during cyclotron operation was estimated to be 4.72 × 10(2) cm(-2) s(-1), and the activation of concrete in a cyclotron laboratory was about three orders of magnitude lower than the clearance level of RS-G-1.7 (IAEA). The activity concentration of the boron-containing water did not exceed the concentration limit for radioactive isotopes in drainage in Japan and the exemption level for Basic Safety Standards. Consequently, the boron-containing water is treatable as non-radioactive waste. Neutrons were effectively shielded by the self-shield during cyclotron operation.

  4. Cyclotron Resonance of Electrons Trapped in a Microwave Cavity

    Science.gov (United States)

    Elmore, W. C.

    1975-01-01

    Describes an experiment in which the free-electron cyclotron resonance of electrons trapped in a microwave cavity by a Penning trap is observed. The experiment constitutes an attractive alternative to one of the Gardner-Purcell variety. (Author/GS)

  5. A simple thick target for production of 89Zr using an 11MeV cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Link, Jeanne M.; Krohn, Kenneth A.; O' Hara, Matthew J.

    2017-04-01

    The growing interest but limited availability of 89Zr for PET led us to test targets for the 89(p,n) reaction. The goal was an easily constructed target for an 11 MeV Siements cyclotron. Yttrium foils were tested at different thicknesses, angles and currents. A 90 degree foil tolerated 41 microAmp without damage and produced ~800 MBq/hr, >20 mCi, an amount adequate for radiochemistry research and human doses in a widely available accelerator. This method should translate to higher energy cyclotrons.

  6. Education for Agricultural Improvement: Teacher Certification at the Agricultural and Mechanical College of Texas

    Science.gov (United States)

    Burlbaw, Lynn M.; Williams, Lauren; Kelly, Larry J.

    2017-01-01

    Texas A&M University has long been known for its engineering and agricultural programs. Only in the last 50 years has its reputation included the preparation of teachers for general education in the public schools of Texas. However, agricultural education has been an integral part of the institution's mandate since early in the 20th century.…

  7. Development of a miniature microwave electron cyclotron resonance plasma ion thruster for exospheric micro-propulsion.

    Science.gov (United States)

    Dey, Indranuj; Toyoda, Yuji; Yamamoto, Naoji; Nakashima, Hideki

    2015-12-01

    A miniature microwave electron cyclotron resonance plasma source [(discharge diameter)/(microwave cutoff diameter) micro-propulsion applications in the exosphere. The discharge source uses both radial and axial magnetostatic field confinement to facilitate electron cyclotron resonance and increase the electron dwell time in the volume, thereby enhancing plasma production efficiency. Performance of the ion thruster is studied at 3 microwave frequencies (1.2 GHz, 1.6 GHz, and 2.45 GHz), for low input powers (<15 W) and small xenon mass flow rates (<40 μg/s), by experimentally measuring the extracted ion beam current through a potential difference of ≅1200 V. The discharge geometry is found to operate most efficiently at an input microwave frequency of 1.6 GHz. At this frequency, for an input power of 8 W, and propellant (xenon) mass flow rate of 21 μg/s, 13.7 mA of ion beam current is obtained, equivalent to an calculated thrust of 0.74 mN.

  8. Differences between the Texas phoenix palm phytoplasma and the ...

    African Journals Online (AJOL)

    ntushk

    Restriction fragment length polymorphisms analysis of the PCR-amplified nusA and the ... Four restriction enzymes were used for the nusA gene and 16 were used for the hflB genes. Key words: nusA, hflB, phytoplasma, Texas Phoenix decline. ..... Lee I-M, Gundersen-Rindall DE, Davis RE, Bottner KD, Marcone C,.

  9. Characterization and performance of a field aligned ion cyclotron range of frequency antenna in Alcator C-Moda)

    Science.gov (United States)

    Wukitch, S. J.; Garrett, M. L.; Ochoukov, R.; Terry, J. L.; Hubbard, A.; Labombard, B.; Lau, C.; Lin, Y.; Lipschultz, B.; Miller, D.; Reinke, M. L.; Whyte, D.; Alcator C-Mod Team

    2013-05-01

    Ion cyclotron range of frequency (ICRF) heating is expected to provide auxiliary heating for ITER and future fusion reactors where high Z metallic plasma facing components (PFCs) are being considered. Impurity contamination linked to ICRF antenna operation remains a major challenge particularly for devices with high Z metallic PFCs. Here, we report on an experimental investigation to test whether a field aligned (FA) antenna can reduce impurity contamination and impurity sources. We compare the modification of the scrape of layer (SOL) plasma potential of the FA antenna to a conventional, toroidally aligned (TA) antenna, in order to explore the underlying physics governing impurity contamination linked to ICRF heating. The FA antenna is a 4-strap ICRF antenna where the current straps and antenna enclosure sides are perpendicular to the total magnetic field while the Faraday screen rods are parallel to the total magnetic field. In principle, alignment with respect to the total magnetic field minimizes integrated E|| (electric field along a magnetic field line) via symmetry. A finite element method RF antenna model coupled to a cold plasma model verifies that the integrated E|| should be reduced for all antenna phases. Monopole phasing in particular is expected to have the lowest integrated E||. Consistent with expectations, we observed that the impurity contamination and impurity source at the FA antenna are reduced compared to the TA antenna. In both L and H-mode discharges, the radiated power is 20%-30% lower for a FA-antenna heated discharge than a discharge heated with the TA-antennas. However, inconsistent with expectations, we observe RF induced plasma potentials (via gas-puff imaging and emissive probes to be nearly identical for FA and TA antennas when operated in dipole phasing). Moreover, the highest levels of RF-induced plasma potentials are observed using monopole phasing with the FA antenna. Thus, while impurity contamination and sources are indeed

  10. The electron-cyclotron maser instability as a source of plasma radiation. [Solar radio bursts

    Science.gov (United States)

    Winglee, R. M.; Dulk, G. A.

    1986-01-01

    The generation of continuum bursts from the sun at dm and m wavelengths (in particular, type IV bursts) via the electron-cyclotron-maser instability is examined. The maser instability can be driven by an electron distribution with either a loss-cone anisotropy or a peak at large pitch angles. For omega(p)/Omega(e) much greater than 1, the maser emission is produced by electrons interacting through a harmonic (cyclotron) resonance and is electrostatic, being in the upper hybrid mode at frequencies approximately equal to omega(p). Coalescence processes are required to convert the electrostatic waves into transverse radiation which can escape from the source region. Whether the resultant spectrum is nearly a smooth continuum or has a zebra-stripe pattern (both of which occur in type IV bursts) depends on the form of the electron distribution, inhomogeneities in the density and magnetic field, and whether the maser reaches saturation. For at least the case of some type IV dm bursts with fine structure, comparison with observations seems to indicate that the electrons producing the emission are more likely to have a loss-cone distribution, and that the maser instability is not at saturation.

  11. Medium to large scale radioisotope production for targeted radiotherapy using a small PET cyclotron

    DEFF Research Database (Denmark)

    Thisgaard, Helge; Jensen, Mikael; Elema, Dennis Ringkjøbing

    2011-01-01

    In recent years the use of radionuclides in targeted cancer therapy has increased. In this study we have developed a high-current solid target system and demonstrated that by the use of a typical low-energy medical cyclotron, it is possible to produce tens of GBq's of many unconventional radionuc......In recent years the use of radionuclides in targeted cancer therapy has increased. In this study we have developed a high-current solid target system and demonstrated that by the use of a typical low-energy medical cyclotron, it is possible to produce tens of GBq's of many unconventional...

  12. Unidirectional stripping extraction from a cyclotron which accelerates light as well as heavy ions

    Directory of Open Access Journals (Sweden)

    Jasna L. Ristić-Djurović

    2003-03-01

    Full Text Available The VINCY Cyclotron (VINča CYclotron is a multipurpose machine intended to accelerate light as well as heavy ions. To extract heavy ions with low energy and light ions an extraction system with stripping foil is used. Heavy ions with high energy will be extracted by means of an electrostatic deflector. The former extraction system will be manufactured and used first. The proposed unidirectional stripping extraction system is the optimal balance between the placement of the extraction line and the required diversity and quality of the extracted beam. The available range of extraction directions is set by geometry limitations.

  13. Production of hydrogen and deuterium negative ions in an electron cyclotron resonance driven plasma

    Energy Technology Data Exchange (ETDEWEB)

    Dougar-Jabon, V.D. [Industrial Univ. of Santander, Bucaramanga (Colombia)

    2001-04-01

    An electron cyclotron resonance source with driven plasma rings for hydrogen isotope ion production is studied. Extracted currents of positive and negative ions depending on gas pressure, microwave power value and extraction voltage are obtained. The study shows that the negative ion yield is an order of magnitude higher than the yield of positive particles when a driven ring is in contact with the surface of the plasma electrode. The production of negative ions of deuterium, D{sup -}, is close to the production of negative ions of light hydrogen isotope, H{sup -}. The comparison of the experimental data with the calculated ones shows that the most probable process of the H{sup -} and D{sup -} ion formation in the electron cyclotron driven plasma is dissociative attachment of electrons to molecules in high Rydberg states. For hydrogen ions and ions of deuterium, the negative current at a microwave power of 200 W through a 3-mm aperture and 8 kV extraction voltage are 4.7 mA and 3.1 mA respectively. (orig.)

  14. Climate Change Impacts on Texas Water: A White Paper Assessment of the Past, Present and Future and Recommendations for Action

    Energy Technology Data Exchange (ETDEWEB)

    Banner, Jay L.; Jackson, Charles S.; Yang, Zong-Liang; Hayhoe, Katharine; Woodhouse, Connie; Gulden, Lindsey; Jacobs, Kathy; North, Gerald; Leung, Lai-Yung R.; Washington, Warren M.; Jiang, Xiaoyan; Casteel, Richard

    2010-09-01

    Texas comprises the eastern portion of the Southwest region, where the convergence of climatological and geopolitical forces has the potential to put extreme stress on water resources. Geologic records indicate that Texas experienced large climate changes on millennial time scales in the past, and over the last thousand years, tree-ring records indicate that there were significant periods of drought in Texas. These droughts were of longer duration than the 1950s 'drought of record' that is commonly used in planning, and they occurred independently of human-induced global climate change. Although there has been a negligible net temperature increase in Texas over the past century, temperatures have increased more significantly over the past three decades. Under essentially all climate model projections, Texas is susceptible to significant climate change in the future. Most projections for the 21st century show that with increasing atmospheric greenhouse gas concentrations, there will be an increase in temperatures across Texas and a shift to a more arid average climate. Studies agree that Texas will likely become significantly warmer and drier, yet the magnitude, timing, and regional distribution of these changes are uncertain. There is a large uncertainty in the projected changes in precipitation for Texas for the 21st century. In contrast, the more robust projected increase in temperature with its effect on evaporation, which is a dominant component in the region's hydrologic cycle, is consistent with model projections of frequent and extended droughts throughout the state. For these reasons, we recommend that Texas invest resources to investigate and anticipate the impacts of climate change on Texas water resources, with the goal of providing data to inform resource planning. This investment should support development of (1) research programs that provide policy-relevant science; (2) education programs to engage future researchers and policy

  15. Cyclotrons with fast variable and/or multiple energy extraction

    Directory of Open Access Journals (Sweden)

    C. Baumgarten

    2013-10-01

    Full Text Available We discuss the possibility in principle of stripping extraction in combination with reverse bends in isochronous separate-sector cyclotrons (and/or fixed field alternating gradient accelerators. If one uses reverse bends between the sectors (instead of or in combination with drifts and places stripper foils at the sector exit edges, the stripped beam has a reduced bending radius and it should be able to leave the cyclotron within the range of the valley—even if the beam is stripped at less than full energy. We are especially interested in stripping of H_{2}^{+}, as it doubles the charge to mass ratio of the ions. However the method could be applied to other ions or ionized molecules as well. For the production of proton beams by stripping extraction of an H_{2}^{+} beam, we discuss possible designs for three types of machines: First, a low-energy cyclotron for the simultaneous production of several beams at multiple energies—for instance 15, 30, and 70 MeV—thus allowing beam delivery on several isotope production targets. In this case it can be an advantage to have a strong energy dependence of the direction of the extracted beam. Second, we consider a fast variable-energy proton machine for cancer therapy that should allow extraction (of the complete beam at all energies in the range of about 70 MeV to about 250 MeV into the same beam line. Third, we consider a high-intensity high-energy machine, where the main design goals are extraction with low losses, low activation of components, and high reliability. Especially if such a machine is considered for an accelerator driven system (ADS, this extraction mechanism has advantages: Beam trips by the failure of electrostatic elements could be avoided and the turn separation would be less critical, which allows operation at lower main cavity voltages. This would in turn reduce the number of rf trips. The price that has to be paid for these advantages is an increase in size and/or field

  16. Risks of developing breast and colorectal cancer in association with incomes and geographic locations in Texas: a retrospective cohort study.

    Science.gov (United States)

    Liu, Zheyu; Zhang, Kai; Du, Xianglin L

    2016-04-26

    No study has been conducted to investigate the spatial pattern and association of socioeconomic status (such as income) with breast and colorectal cancer incidence in Texas, United States. This study aimed to determine whether median household income was associated with the risk of developing breast and colorectal cancer in Texas and to identify higher cancer risks by race/ethnicity and geographic areas. This was a retrospective cohort study with an ecological component in using aggregated measures at the county level. We identified 243,677 women with breast cancer and 155,534 men and women with colorectal cancer residing in 254 counties in Texas in 1995-2011 from the public-use dataset of Texas Cancer Registry. The denominator population and median household income at the county level was obtained from the U.S. Bureau of the Census. Cancer incidence rates were calculated as number of cases per 100,000 persons and age-adjusted using the 2000 US population data. We used the ArcGIS v10.1 (geographic information system software) to identify multiple clustered counties with high and low cancer incidences in Texas. Age-adjusted breast cancer incidence rate in the highest median income quintile group was 151.51 cases per 100,000 in 2008-2011 as compared to 98.95 cases per 100,000 in the lowest median income quintile group. The risk of colorectal cancer appeared to decrease with increasing median income in racial/ethnic population. Spatial analysis revealed the significant low breast cancer incidence cluster regions located in southwest US-Mexico border counties in Texas. This study demonstrated that higher income was associated with an increased risk of breast cancer and a decreased risk of colorectal cancer in Texas. There were geographic variations with cancer incidence clustered in high risk areas in Texas. Future studies may need to explore more factors that might explain income and cancer risk associations and their geographic variations.

  17. DRAFT LANDSAT DATA MOSAIC: MONTGOMERY COUNTY, TEXAS; HARRIS COUNTY, TEXAS; FORT BEND COUNTY, TEXAS; BRAZORIA COUNTY, TEXAS; GALVESTON COUNTY, TEXAS

    Science.gov (United States)

    This is a draft Landsat Data Mosaic, which contains remote sensing information for Montgomery County, Texas Harris County, Texas Fort Bend County, Texas Brazoria County, Texas Galveston County, and Texas Imagery dates on the following dates: October 6, 1999 and September 29, 200...

  18. Archaeological Survey of Cooper Lake, Number 6, 1989. Cultural Resource Studies for Cooper Lake, Hopkins and Delta Counties, Texas

    Science.gov (United States)

    1989-01-01

    The disinterment was performed according comnposition cf the historic landscape consisted of to an explicit bioarchaeological and forensic a...consistM solely of One unique item, a Waco sinker formed on a surface collection. Whole (55.8%) and bri)en quartz cobble, was recovered. This artifact is...Hopkins County, Texas. Texian Society, Special Publication No. 1 and Texas Press, Waco , Texas. Memorial Museum Bulletin, No. 4, Austin. Saunders, Joe W

  19. Cyclotron Resonance Gain for FIR and THz Radiation in Graphene

    CERN Document Server

    Cole, Nightvid

    2016-01-01

    A cyclotron resonance maser source using low-effective-mass conduction electrons in graphene, if successful, would allow for generation of Far Infrared (FIR) and Terahertz (THz) radiation without requiring magnetic fields running into the tens of Tesla. In order to investigate this possibility, we consider a device in which electrons are effectively injected via pumping from the valence band to the conduction band using an infrared (IR) laser source, subsequently gyrate in a magnetic field applied perpendicular to the plane of the graphene, and give rise to gain for a FIR/THz wave crossing the plane of the graphene. A set of integral expressions is derived by assuming that the non-radiative energy loss processes of the electrons can be adequately represented by a damping force proportional and antiparallel to their momentum. Minimal gain may occur at very short electron damping times of hundreds of femtoseconds.

  20. The TXESS Revolution: A Partnership to Advance Earth and Space Science in Texas

    Science.gov (United States)

    Ellins, K. K.; Olson, H. C.; Willis, M.

    2007-12-01

    The Texas State Board of Education voted in 2006 to require a fourth year of science for graduation from high school and to authorize the creation of a new senior level Earth Systems and Space Science course as an option to fulfill that requirement. The new Earth Systems and Space Science course will be a capstone course for which three required science courses(biology, chemistry and physics)are prerequisites. Here, we summarize the collective efforts of business leaders, scientists and educators who worked collaboratively for almost a decade to successfully reinstate Earth science as part of Texas' standard high school curriculum and describe a new project, the Texas Earth and Space Science (TXESS) Revolution, a 5-year professional development program for 8th -12th grade minority and minority-serving science teachers and teacher mentors in Texas to help prepare them to teach the new capstone course. At the heart of TXESS Revolution is an extraordinary partnership, involving (1) two UT-Austin academic units, the Jackson School of Geosciences and the Department of Petroleum and Geosystems Engineering; (2) TERC, a not-for-profit educational enterprise in Massachusetts with 30 years experience in designing science curriculum; (3) the University of South Florida; and (4) the Texas Regional Collaboratives for Excellence in Science and Mathematics Teaching, a statewide network of teacher mentors and science teachers. With guidance from the Texas Education Agency, the state agency charged with overseeing education, the TXESS Revolution project will provide teachers with access to high quality materials and instruction aligned with the Texas educational standards for the new capstone course through: a program of eight different 3-day professional development academies offered to both teachers and teachers mentors; immersive summer institutes, field experiences, and a Petroleum Science and Technology Institute; training on how to implement Earth Science by Design, a teacher

  1. Why NASA and the Space Electronics Community Cares About Cyclotrons

    Science.gov (United States)

    LaBel, Kenneth A.

    2017-01-01

    NASA and the space community are faced with the harsh reality of operating electronic systems in the space radiation environment. Systems need to work reliably (as expected for as long as expected) and be available during critical operations such as docking or firing a thruster. This talk will provide a snapshot of the import of ground-based research on the radiation performance of electronics. Discussion topics include: 1) The space radiation environment hazard, 2) Radiation effects on electronics, 3) Simulation of effects with cyclotrons (and other sources), 4) Risk prediction for space missions, and, 5) Real-life examples of both ground-based testing and space-based anomalies and electronics performance. The talk will conclude with a discussion of the current state of radiation facilities in North America for ground-based electronics testing.

  2. Electromagnetic ion/ion cyclotron instability - Theory and simulations

    Science.gov (United States)

    Winske, D.; Omidi, N.

    1992-01-01

    Linear theory and 1D and 2D hybrid simulations are employed to study electromagnetic ion/ion cyclotron (EMIIC) instability driven by the relative streaming of two field-aligned ion beams. The characteristics of the instability are studied as a function of beam density, propagation angle, electron-ion temperature ratios, and ion beta. When the propagation angle is near 90 deg the EMIIC instability has the characteristics of an electrostatic instability, while at smaller angles electromagnetic effects play a significant role as does strong beam coupling. The 2D simulations point to a narrowing of the wave spectrum and accompanying coherent effects during the linear growth stage of development. The EMIIC instability is an important effect where ion beta is low such as in the plasma-sheet boundary layer and upstream of slow shocks in the magnetotail.

  3. Absorption and emission of extraordinary-mode electromagnetic waves near cyclotron frequency in nonequilibrium plasmas

    Science.gov (United States)

    Wu, C. S.; Lin, C. S.; Wong, H. K.; Tsai, S. T.; Zhou, R. L.

    1981-01-01

    An investigation is presented of two cases: (1) weakly relativistic electrons with a loss-cone type distribution, and (2) electrons with a drift velocity parallel to the ambient magnetic field. Numerical computations are given for physical parameters close to those in the polar region of the earth magnetosphere and laboratory experiments, with attention to the fast extraordinary-mode radiation whose frequency is near that of the electron cyclotron frequency. The fast extraordinary mode can escape from a strong field region to the weaker field region and may therefore be measured outside the plasma. It is found that the X mode radiation can be amplified by means of a cyclotron maser effect when the electrons have a loss-cone distribution, and it is concluded that, when the electron energy is sufficiently high, the X mode cutoff frequency may be lower than the cyclotron frequency.

  4. A gas-jet transport and catcher technique for on-line production of radioactive ion beams using an electron cyclotron resonance ion-source

    Energy Technology Data Exchange (ETDEWEB)

    Naik, V.; Chakrabarti, A.; Bhattacharjee, M.; Karmakar, P.; Bandyopadhyay, A.; Dechoudhury, S.; Mondal, M.; Pandey, H. K.; Lavanyakumar, D.; Mandi, T. K.; Dutta, D. P.; Kundu Roy, T.; Bhowmick, D.; Sanyal, D.; Srivastava, S. C. L.; Ray, A.; Ali, Md. S. [Variable Energy Cyclotron Centre (VECC), Sector-1, Block-AF, Bidhan Nagar, Kolkata 700064 (India); Bhattacharjee, S. [UGC-DAE CSR, Kolkata Centre, III/LB-8, Bidhan Nagar, Kolkata 700098 (India)

    2013-03-15

    Radioactive ion beams (RIB) have been produced on-line, using a gas-jet recoil transport coupled Electron Cyclotron Resonance (ECR) ion-source at the VECC-RIB facility. Radioactive atoms/molecules carried through the gas-jet were stopped in a catcher placed inside the ECR plasma chamber. A skimmer has been used to remove bulk of the carrier gas at the ECR entrance. The diffusion of atoms/molecules through the catcher has been verified off-line using stable isotopes and on-line through transmission of radioactive reaction products. Beams of {sup 14}O (71 s), {sup 42}K (12.4 h), {sup 43}K (22.2 h), and {sup 41}Ar (1.8 h) have been produced by bombarding nitrogen and argon gas targets with proton and alpha particle beams from the K130 cyclotron at VECC. Typical measured intensity of RIB at the separator focal plane is found to be a few times 10{sup 3} particles per second (pps). About 3.2 Multiplication-Sign 10{sup 3} pps of 1.4 MeV {sup 14}O RIB has been measured after acceleration through a radiofrequency quadrupole linac. The details of the gas-jet coupled ECR ion-source and RIB production experiments are presented along with the plans for the future.

  5. Forest Clearcutting and Site Preparation on a Saline Soil in East Texas: Impacts on Water Quality

    Science.gov (United States)

    Matthew McBroom; Mingteh Chang; Alexander K. Sayok

    2002-01-01

    Three 0.02 hectare plot-watersheds were installed on a saline soil in the Davy Crockett National Forest near Apple Springs, Texas. Each plot was installed with an H-flume, FW-1 automatic water level recorder, Coshocton N-1 runoff sampler, and two storage tanks. One watershed was undisturbed forested and served a control, one was clearcut without any site-preparation,...

  6. A Survey of Electron Cyclotron Waves in the Magnetosphere and the Diffuse Auroral Electron Precipitation

    Science.gov (United States)

    1990-03-09

    nature of these waves. Based on the cases examined in detail using the methods presented in Figures 1-6, we have found that the majority of emis- sions...precipitation can be identified, it will be difficult to access quantitatively its effects on the magnetospheric system. It seems that the only method of solving...REFERENCES Ashour-Abdalla, H., and C. F. Kennel, Diffuse auroral precipitation, J. Geomag. Geoelectr ., 30, 239-255, 1978. Barbosa, D. D., On the convective

  7. Preliminary Findings for a Relationship between Instream Flow and Shoal Chub Recruitment in the Lower Brazos River, Texas

    National Research Council Canada - National Science Library

    Rodger, Anthony W; Mayes, Kevin B; Winemiller, Kirk O

    2016-01-01

    ... hyostoma, a broadcast-spawning minnow in the Brazos River, Texas. From March 2013 to March 2014, we collected metalarval and juvenile Shoal Chub bimonthly at night using arrays of stationary drift nets...

  8. [Decommissioning of the medical cyclotron in National Center of Neurology and Psychiatry].

    Science.gov (United States)

    Ito, Kimiteru; Nakata, Yasuhiro; Matsuda, Hiroshi; Sato, Noriko

    2011-05-01

    In Japan, positron emission tomography has prevailed as a useful procedure for detecting malignancy, myocardial viability, and epileptic foci. Consequently, compact medical cyclotrons have been installed in many hospitals. However, reports about the dismantling or decommissioning of compact medical cyclotrons are rare. This report describes the series of steps involved in the decommissioning of a compact medical cyclotron that had been used to produce radioactively tagged substances over a period of fifteen years at the National Center of Neurology and Psychiatry in Japan. Additionally, this report describes the manner in which the radioactive waste was disposed. The plan to decommission the cyclotron was comprised of three phases: a preliminary survey, the dismantling work, and a reports after the dismantling. We complied with the guidelines for the disposal of radioactive waste published by the Ministry of Education, Culture, Sports, Science and Technology. The most radioactive material was the vacuuming foil used in the window of the target chamber, with a dose rate of 17 microSv/h (gamma rays) and 20 x 10(3) cpm (beta rays). The detected radionuclides were mainly 22Na, 57Co, 60Co and 65Zn. The total numbers of radioactive waste containers were thirteen 200 l containers and one 50 l container. We suspect that the long shutdown period of the cyclotron (more than one year) contributed to the decay of the radioactive waste because the amount of containers was smaller than the initial estimation. The shutdown period of a cyclotron may play a significant role in reducing the amount of radioactive waste.

  9. Wheelerodemus muhlenbergiae, a new genus and new species of Blissidae (Hemiptera: Heteroptera: Lygaeoidea) from Oklahoma and Texas

    Science.gov (United States)

    Abstract.— The new blissid genus Wheelerodemus is described to accommodate the new species W. muhlenbergiae, based on specimens collected on the grasses Muhlenbergia lindheimeri and M. reverchonii from the Arbuckle Mountains in southcentral Oklahoma and the Edward’s Plateau in westcentral Texas. Bec...

  10. Innovative Developmental Education Programs: A Texas Model

    Science.gov (United States)

    Booth, Eric A.; Capraro, Mary Margaret; Capraro, Robert M.; Chaudhuri, Nandita; Dyer, James; Marchbanks, Miner P., III

    2014-01-01

    This article provides insights from a 2-year, cross-site evaluation of state funded developmental education sites and serves as a focus article for response by those sites. Receiving grants from the Texas Higher Education Coordinating Board (THECB), nine sites (5 community colleges and 4 universities) implemented innovative developmental education…

  11. Texas site selection and licensing status

    Energy Technology Data Exchange (ETDEWEB)

    Avant, R.V. Jr.

    1989-11-01

    Texas has identified a potential site in Hudspeth County in far West Texas near the town of Fort Hancock. Over the past year the Texas Low-Level Radioactive Waste Disposal Authority has been conducting detailed geology, hydrology, meteorology, soils, and flora and fauna evaluations. An authorization by the Board of Directors of the Authority to proceed with a license application, assuming that the detailed evaluation indicates that the site is suitable, is expected by September. A prototype license has been prepared in anticipation of the order to proceed with licensing, and the formal license application is expected to be submitted to the Texas Department of Health-Bureau of Radiation Control in December, meeting the license application milestone. Although site selection processes in all siting areas across the country have experienced organized opposition, El Paso County has funded a particularly well-organized, well-financed program to legally and technically stop consideration of the Fort Hancock site prior to the licensing process. Many procedural, regulatory, and technical issues have been raised which have required responses from the Authority in order to proceed with licensing. This has provided a unique perspective of what to expect from well-organized opposition at the licensing stage. This paper presents an update on the Texas siting activity with detailed information on the site evaluation and license application. Experience of dealing with issues raised by opposition relating to NRC guidelines and rules is also discussed.

  12. Characterization of the onset of ion cyclotron parametric decay instability of lower hybrid waves in a diverted tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Baek, S. G., E-mail: sgbaek@mit.edu; Parker, R. R.; Shiraiwa, S.; Wallace, G. M.; Bonoli, P. T.; Porkolab, M.; Brunner, D.; Faust, I. C.; Hubbard, A. E.; LaBombard, B.; Lau, C. [MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139 (United States); Takase, Y. [University of Tokyo, Kashiwa 277-8561 (Japan)

    2014-06-15

    The goal of the lower hybrid current drive (LHCD) program on Alcator C-Mod is to develop and optimize reactor-relevant steady-state plasmas by controlling current density profile. However, current drive efficiency precipitously decreases as the line averaged density (n{sup ¯}{sub e}) increases above ∼1 × 10{sup 20} m{sup −3}. Previous simulations show that the observed loss of current drive efficiency in high density plasmas stems from the interactions of LH waves with edge/scrape-off layer plasmas [Wallace et al., Phys. Plasmas 19, 062505 (2012)]. A recent observation [Baek et al., Plasma Phys. Controlled Fusion 55, 052001 (2013)] shows that the configuration dependent ion cyclotron parametric decay instability (PDI) is excited in the density range where the discrepancy between the experiments and simulations remains. Comparing the observed spectra with the homogeneous growth rate spectra indicates that the observed ion cyclotron PDI can be excited not only at the low-field-side but also at the high-field-side (HFS) edge of the tokamak. The model analysis shows that a relevant PDI process to Alcator C-Mod LHCD experiments is decay into ion cyclotron quasi-mode driven by parallel coupling. The underlying cause of the observed onset of ion cyclotron PDI is likely due to the weaker radial penetration of the LH wave in high density plasmas, which can lead to enhanced convective growth. Configuration-dependent PDIs are found to be correlated with different edge density profiles in different magnetic configurations. While the HFS edge of the tokamak can be potentially susceptible to PDI, as evidenced by experimental observations and ray-tracing analyses, enhancing single-pass absorption is expected to help recover the LHCD efficiency at reactor-relevant densities because it could suppress several parasitic loss mechanisms that are exacerbated in multi-pass regimes.

  13. Characterization of the onset of ion cyclotron parametric decay instability of lower hybrid waves in a diverted tokamak

    Science.gov (United States)

    Baek, S. G.; Parker, R. R.; Shiraiwa, S.; Wallace, G. M.; Bonoli, P. T.; Porkolab, M.; Takase, Y.; Brunner, D.; Faust, I. C.; Hubbard, A. E.; LaBombard, B.; Lau, C.

    2014-06-01

    The goal of the lower hybrid current drive (LHCD) program on Alcator C-Mod is to develop and optimize reactor-relevant steady-state plasmas by controlling current density profile. However, current drive efficiency precipitously decreases as the line averaged density (n¯e) increases above ˜1 × 1020 m-3. Previous simulations show that the observed loss of current drive efficiency in high density plasmas stems from the interactions of LH waves with edge/scrape-off layer plasmas [Wallace et al., Phys. Plasmas 19, 062505 (2012)]. A recent observation [Baek et al., Plasma Phys. Controlled Fusion 55, 052001 (2013)] shows that the configuration dependent ion cyclotron parametric decay instability (PDI) is excited in the density range where the discrepancy between the experiments and simulations remains. Comparing the observed spectra with the homogeneous growth rate spectra indicates that the observed ion cyclotron PDI can be excited not only at the low-field-side but also at the high-field-side (HFS) edge of the tokamak. The model analysis shows that a relevant PDI process to Alcator C-Mod LHCD experiments is decay into ion cyclotron quasi-mode driven by parallel coupling. The underlying cause of the observed onset of ion cyclotron PDI is likely due to the weaker radial penetration of the LH wave in high density plasmas, which can lead to enhanced convective growth. Configuration-dependent PDIs are found to be correlated with different edge density profiles in different magnetic configurations. While the HFS edge of the tokamak can be potentially susceptible to PDI, as evidenced by experimental observations and ray-tracing analyses, enhancing single-pass absorption is expected to help recover the LHCD efficiency at reactor-relevant densities because it could suppress several parasitic loss mechanisms that are exacerbated in multi-pass regimes.

  14. New compact and efficient local oscillator optic system for the KSTAR electron cyclotron emission imaging system

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Y. B., E-mail: southub@postech.ac.kr; Yun, G. S. [Department of Physics, Pohang University of Science and Technology, Pohang 37673 (Korea, Republic of); Lee, D. J.; Lee, J.; Lee, W. [Ulsan National Institute of Science and Technology, Ulsan 44919 (Korea, Republic of); Kim, C. [Pennsylvania State University, Old Main, State College, Pennsylvania 16801 (United States); Park, H. K. [Ulsan National Institute of Science and Technology, Ulsan 44919 (Korea, Republic of); National Fusion Research Institute, Daejeon 34133 (Korea, Republic of)

    2016-11-15

    Electron cyclotron emission imaging (ECEI) diagnostic on Korean Superconducting Tokamak Advanced Research utilizes quasi-optical heterodyne-detection method to measure 2D (vertical and radial) T{sub e} fluctuations from two toroidally separated poloidal cross section of the plasma. A cylindrical lens local oscillator (LO) optics with optical path length (OPL) 2–2.5 m has been used in the current ECEI system to couple the LO source to the 24 vertically aligned array of ECE detectors. For efficient and compact LO optics employing the Powell lens is proposed so that the OPL of the LO source is significantly reduced from ∼2.0 m to 0.4 m with new optics. The coupling efficiency of the LO source is expected to be improved especially at the edge channels. Results from the optical simulation together with the laboratory test of the prototype optics will be discussed in this paper.

  15. ROKCY-12 (KCCH PET-dedicated cyclotron): main features and improvements

    Energy Technology Data Exchange (ETDEWEB)

    Chai, J. S.; Kim, Y. S.; Yang, Y. T.; Jung, I. S.; Hong, S. S.; Lee, M. Y.; Jang, H. S.; Kim, J. H. [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    2002-07-01

    In this paper, we describe the development of 13 MeV cyclotron (ROKCY-12) that can be used for a Position Emission Tomography(PET) purpose. This cyclotron with a maximum beam energy of 13 MeV can produce radio isotopes especially {sup 18}F which has a relatively short half lifetime of 110 minutes. First, we show the beam characteristics can be used to carry out the operation of ROCKY-12. Based on this, a computer program has been developed to determine main cyclotron parameters such as cyclotron magnet, RF system, ion source, vacuum system and other cyclotron operation parameters. And then we show the result of design and manufacturing feature of ROKCY-12. By using this design program, one can determines magnet yoke geometry and the average magnetic fields etc. And then the three-dimensional computer program OPERA-3D has been invoked to determine magnet pole tips. Validity of the design can be seen by investigating magnetic fields, radial and vertical focusing frequencies as a function of the beam energy. In this paper, we show the results of cyclotron beam by ROCKY-12. We designed 77.3 MHz RF system and ion source system. We tested RF resonance each coupling methods. We show the result of RF design and prototype operation. Developed ion source is PIG type. We described our design methods and implementation. We report the result of getting negative hydrogen ion. Cyclotron controller asks inputs of every sensor and output of every instrument for notifying current condition to operator. It has independent controllers, for example DC power supply, vacuum system, beam profile system, beam extraction system, RF system, ion source, cooling unit and so on. Basically, each control system uses RS-485 for communication to main control computer. Consumers reward products and services that feature quality, originality, a distinct personality and charm. The International Standardization Organization (ISO) requires, as its mission, that we achieve competitive superiority by

  16. Multi‐instrument observations from Svalbard of a traveling convection vortex, electromagnetic ion cyclotron wave burst, and proton precipitation associated with a bow shock instability

    DEFF Research Database (Denmark)

    Engebretson, M. J.; Yeoman, T. K.; Oksavik, K.

    2013-01-01

    An isolated burst of 0.35 Hz electromagnetic ion cyclotron (EMIC) waves was observed at four sites on Svalbard from 0947 to 0954 UT 2 January 2011, roughly 1 h after local noon. This burst was associated with one of a series of ~50 nT magnetic impulses observed at the northernmost stations......-based observations of the Hα line at Longyearbyen indicated proton precipitation at the same time as the EMIC wave burst, and NOAA-19, which passed over the west coast of Svalbard between 0951 and 0952, observed a clear enhancement of ring current protons at the same latitude. Electron precipitation from this same...... satellite indicated that the EMIC burst was located on closed field lines, but near to the polar cap boundary. We believe these are the first simultaneous observations of EMIC waves and precipitating energetic protons so near to the boundary of the dayside magnetosphere. Although several spacecraft upstream...

  17. Stability of electrostatic ion cyclotron waves in a multi-ion plasma†

    Indian Academy of Sciences (India)

    Abstract. We have studied the stability of the electrostatic ion cyclotron wave in a plasma consisting of isotropic hydrogen ions (H+) and temperature-anisotropic positively. (O+) and negatively (O−) charged oxygen ions, with the electrons drifting parallel to the magnetic field. Analytical expressions have been derived for the ...

  18. (44g)Sc production using a water target on a 13MeV cyclotron.

    Science.gov (United States)

    Hoehr, Cornelia; Oehlke, Elisabeth; Benard, Francois; Lee, Chris Jaeil; Hou, Xinchi; Badesso, Brian; Ferguson, Simon; Miao, Qing; Yang, Hua; Buckley, Ken; Hanemaayer, Victoire; Zeisler, Stefan; Ruth, Thomas; Celler, Anna; Schaffer, Paul

    2014-01-01

    Access to promising radiometals as isotopes for novel molecular imaging agents requires that they are routinely available and inexpensive to obtain. Proximity to a cyclotron center outfitted with solid target hardware, or to an isotope generator for the metal of interest is necessary, both of which can introduce significant hurdles in development of less common isotopes. Herein, we describe the production of ⁴⁴Sc (t1/2=3.97 h, Eavg,β⁺=1.47MeV, branching ratio=94.27%) in a solution target and an automated loading system which allows a quick turn-around between different radiometallic isotopes and therefore greatly improves their availability for tracer development. Experimental yields are compared to theoretical calculations. Solutions containing a high concentration (1.44-1.55g/mL) of natural-abundance calcium nitrate tetrahydrate (Ca(NO₃)2·4 H₂O) were irradiated on a 13MeV proton-beam cyclotron using a standard liquid target. (44g)Sc was produced via the ⁴⁴Ca(p,n)(44g)Sc reaction. (44g)Sc was produced for the first time in a solution target with yields sufficient for early radiochemical studies. Saturation yields of up to 4.6 ± 0.3 MBq/μA were achieved using 7.6 ± 0.3 μA proton beams for 60.0 ± 0.2 minutes (number of runs n=3). Experimental data and calculation results are in fair agreement. Scandium was isolated from the target mixture via solid-phase extraction with 88 ± 6% (n=5) efficiency and successfully used for radiolabelling experiments. The demonstration of the production of ⁴⁴Sc in a liquid target greatly improves its availability for tracer development. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Fourier Transform Ion Cyclotron Resonance Mass Spectrometry at the Cyclotron Frequency.

    Science.gov (United States)

    Nagornov, Konstantin O; Kozhinov, Anton N; Tsybin, Yury O

    2017-04-01

    The phenomenon of ion cyclotron resonance allows for determining mass-to-charge ratio, m/z, of an ensemble of ions by means of measurements of their cyclotron frequency, ω c . In Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), the ω c quantity is usually unavailable for direct measurements: the resonant state is located close to the reduced cyclotron frequency (ω+), whereas the ω c and the corresponding m/z values may be calculated via theoretical derivation from an experimental estimate of the ω+ quantity. Here, we describe an experimental observation of a new resonant state, which is located close to the ω c frequency and is established because of azimuthally-dependent trapping electric fields of the recently developed ICR cells with narrow aperture detection electrodes. We show that in mass spectra, peaks close to ω+ frequencies can be reduced to negligible levels relative to peaks close to ω c frequencies. Due to reduced errors with which the ω c quantity is obtained, the new resonance provides a means of cyclotron frequency measurements with precision greater than that achieved when ω+ frequency peaks are employed. The described phenomenon may be considered for a development into an FT-ICR MS technology with increased mass accuracy for applications in basic research, life, and environmental sciences. Graphical Abstract ᅟ.

  20. Geopressured geothermal resource of the Texas and Louisiana Gulf Coast: a technology characterization and environmental assessment

    Energy Technology Data Exchange (ETDEWEB)

    Usibelli, A.; Deibler, P.; Sathaye, J.

    1980-12-01

    Two aspects of the Texas and Louisiana Gulf Coast geopressured geothermal resource: (1) the technological requirements for well drilling, completion, and energy conversion, and, (2) the environmental impacts of resource exploitation are examined. The information comes from the literature on geopressured geothermal research and from interviews and discussions with experts. The technology characterization section emphasizes those areas in which uncertainty exists and in which further research and development is needed. The environmental assessment section discusses all anticipated environmental impacts and focuses on the two largest potential problems: (a) subsidence and (b) brine disposal.

  1. Simulation on the electronic wave packet cyclotron motion in a Weyl semimetal slab.

    Science.gov (United States)

    Yao, Haibo; Zhu, Mingfeng; Jiang, Liwei; Zheng, Yisong

    2017-04-20

    We perform a numerical simulation on the time evolution of an electronic wave packet in a Weyl semimetal (WSM) slab driven by a magnetic field. We find that the evolution trajectory of the wave packet depends sensitively on its initial spin state. Only with initial spin state identical to that of the Fermi arc state at the surface it localized, does the wave packet evolution demonstrate the characteristic cyclotron orbit of WSM previously predicted from a semiclassical viewpoint. By analyzing the eigen-expansion of the electronic wave packet, we find the chiral Landau levels (LLs) of the WSM slab, as ingredients of the wave packet, to be responsible for establishing the characteristic WSM cyclotron orbit. In contrast, the nonchiral LLs contribute irregular oscillations to the wave packet evolution, going against the formation of a well-defined cyclotron orbit. In addition, the tilted magnetic field does not affect the motion of the electronic wave packet along the Fermi arcs in the momentum space. It does, however, alter the evolution trajectory of the electronic wave packet in real space and spin space. Finally, the energy disalignment of the Weyl nodes results in a 3D cyclotron orbit in real space.

  2. Effect of ion clouds micromotion on measured signal in Fourier transform ion cyclotron resonance: Computer simulation.

    Science.gov (United States)

    Vladimirov, Gleb; Kostyukevich, Yury; Kharybin, Oleg; Nikolaev, Eugene

    2017-08-01

    Particle-in-cell-based realistic simulation of Fourier transform ion cyclotron resonance experiments could be used to generate ion trajectories and a signal induced on the detection electrodes. It has been shown recently that there is a modulation of "reduced" cyclotron frequencies in ion cyclotron resonance signal caused by Coulomb interaction of ion clouds. In this work it was proposed to use this modulation in order to determine frequency difference between an ion of known m/z and all other ions generating signal in ion cyclotron resonance cell. It is shown that with an increase of number of ions in ion cyclotron resonance trap, the modulation index increases, which lead to a decrease in the accuracy of determination of peak intensities by super Fourier transform resolution methods such as filter diagonalization method.

  3. Goodenough Spring, Texas, USA: Discharge and water chemistry of a large spring deeply submerged under the binational Amistad Reservoir

    Science.gov (United States)

    Kamps, Ray H.; Tatum, Gregg S.; Gault, Mike; Groeger, Alan W.

    2009-06-01

    Goodenough Spring (Texas, USA) is a large spring near the border of the American state of Texas and the Mexican state of Coahuila, discharging into the international Amistad Reservoir on the river Rio Grande (Rio Bravo). Discharge was routinely measured from 1928 until 1968 to partition the flow of the river between the two countries in accordance with water-use treaties. Samples were analyzed for water-quality parameters in 1967-1968 prior to inundation under 45 m of Amistad Reservoir in 1968. Subsequently, discharge has been estimated indirectly by the International Boundary and Water Commission (IBWC). For the first direct measurements of the spring in 37 years, velocity and cross-sectional measurements were made and water samples collected in the summer of 2005 using advanced self-contained underwater breathing apparatus (SCUBA) techniques. Spring discharge was calculated at 2.03 m3 s-1, approximately one-half of the historical mean of 3.94 m3 s-1. In situ and laboratory analyses of samples for temperature, pH, dissolved oxygen, specific conductance, alkalinity, nitrate-nitrogen, dissolved solids, chloride, sulfate, fluoride, phosphorus, calcium, sodium, potassium, magnesium, and iron showed the water quality to be very good for human consumption and crop irrigation. Measurement values are relatively unchanged from those reported 37 years prior.

  4. Ion cyclotron waves during the Rosetta approach phase: a magnetic estimate of cometary outgassing

    Directory of Open Access Journals (Sweden)

    M. Volwerk

    2013-12-01

    Full Text Available A theoretical model for the ion cyclotron wave generation during the approach phase of Rosetta to 67P/Churyumov–Gerasimenko is presented. For various activity levels of the comet, the crossing of the observational threshold is determined, whose level is derived from the wave power in the undisturbed solar wind near the comet's location during the approach phase at the appropriate frequency. The Giotto flyby at 27P/Grigg–Skjellerup is used to obtain an estimate of how often water-group ion cyclotron waves are observed, and to get insight into the wave forms. At 67P/Churyumov–Gerasimenko one can expect to observe water-group ion cyclotron waves already at a distance of 600 000 km from the nucleus for a nominal outgassing rate of Q = 350 × 1023 molecules per second. The observed first location of cyclotron waves during the Rosetta approach phase will give an indication of the actual outgassing rate of the comet.

  5. A Kinetic Model of Solar Wind Generation by Oblique Ion-cyclotron Waves

    Science.gov (United States)

    Isenberg, Philip A.; Vasquez, Bernard J.

    2011-04-01

    The fast solar wind is generated by extended perpendicular ion heating in coronal holes, but the kinetic mechanism responsible for this heating has not been determined. One long-standing possibility is the resonant-cyclotron dissipation of ion-cyclotron waves, replenished from a turbulent cascade of interacting counter-propagating Alfvén waves. We present results of a kinetic model for proton heating by the quasilinear resonant-cyclotron wave-particle interaction in a coronal hole. The resonant wave spectrum is taken as a power law in wavenumber, uniformly distributed in propagation direction between 0° and 60° with respect to the large-scale radial magnetic field. We obtain the steady-state solution of the kinetic guiding-center equation for the proton distribution in an expanding coronal hole, including the effects of large-scale forces of gravity, charge-separation electric field, Alfvén wave ponderomotive force, and mirror force, along with the small-scale scattering from the wave dissipation. We find that plausible wave intensities can yield reasonable flow speeds and temperatures in the heliocentric radial range between 2 and 6 solar radii. We address the claim in earlier work that dissipation of parallel-propagating ion-cyclotron waves cannot provide enough acceleration and show that claim to be incorrect. We find that the combined action of the large-scale forces and the resonant-cyclotron scattering produces proton distribution functions with a characteristic structure: compressed in the sunward half of velocity space with a high-density shell separate from the origin, and relatively expanded in the anti-sunward half of velocity space. We suggest that qualitatively similar proton distributions would result from the kinetic evolution of any sufficiently effective perpendicular heating mechanism operating in an expanding coronal hole.

  6. TRIUMF cyclotron vacuum system refurbishing

    Science.gov (United States)

    Sekachev, I.

    2008-03-01

    The cyclotron at TRIUMF was commissioned to full energy in 1974. The volume of the cyclotron vacuum tank is about 100 m3 and it operates at 5×10-8 Torr pressure during beam production. The pumping is mainly based on a Phillips B-20 cryogenerator (Stirling cycle 4-cylinder engine). The cryogenerator supplies helium gas at 16 K and 70 K to cryopanels in the tank. The decreasing reliability of the B-20 and demanding maintenance requirements triggered the decision to completely overhaul or replace the cryogenerator. Replacement with the LINDE-1630 helium refrigerator was found to be the most attractive (technically and economically) option. The details of the proposal with installation of the helium refrigerator and with a continuous flow liquid nitrogen shield cooling system are presented.

  7. Production of cyclotron radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Suh, Yong Sup; Lim, Sang Moo; Yang, Seung Dae; Chun, Kwon Soo; Ahn, Soon Hyuk; Yun, Yong Kee; Park, Hyun; Lee, Ji Sup; Lee, Jong Doo; Chai, Jong Seo; Kim, Yoo Seok; Hong, Sung Suk; Lee, Min Yong; Beak, Seung Ki [Korea Cancer Center Hospital, Seoul (Korea)

    1999-12-01

    In the project, 11,492mCi of {sup 201}Tl, 4,384mCi of {sup 67}Ga, 1,245mCi of {sup 123}l, 523mCi of [{sup 123}I]mlBG and 1,283mCi of {sup 18}FDG were supplied, and the revenue were 304,723,000won. In the production of RI, 13 deg for {sup 201}Tl and {sup 67}Ga, 45 deg for {sup 123}l angle solid target have been used, and liquid target system has been used for {sup 18}F production. For the efficient use of the cyclotron, the MC-50 cyclotron was opened to outside user and basic research project was carried out. The technical supports and radionuclides analysis were done during the execution of the research. Then the facilities of safety supervision and handling techniques of radioisotope production were improved. 7 refs., 9 figs., 8 tabs. (Author)

  8. Production of cyclotron radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Kwon Soo; Lim, Sang Moo; Yang, Seung Dae; Suh, Yong Sup; Ahn, Soon Hyuk; Yun, Yong Kee; Park, Hyun; Lee, Ji Sup; Chai, Jong Seo; Kim, Yoo Seok; Hong, Sung Suk; Lee, Min Yong; Beak, Seung Ki; Kim, Jang Hye; Kim, Gi Sup [Korea Cancer Center Hospital, Seoul (Korea)

    2000-12-01

    In the project, 12,077mCi of {sup 201}Tl, 5,717mCi of {sup 67}Ga, 2,096mCi of {sup 123}l, 482mCi of [{sup 123}I]mlBG and 2,738mCi of {sup 18}FDG were supplied, and the revenue were 387,253,000won. In the production of RI, 13 deg for {sup 201}Tl and {sup 67}Ga, 45 deg for {sup 123}l angle solid target have been used, and liquid target system has been used for {sup 18}F production. For the efficient use of the cyclotron, the MC-50 cyclotron was opened to outside user and basic research project was carried out. The technical supports and radionuclides analysis were done during the execution of the research. Then the facilities of safety supervision and handling techniques of radioisotope production were improved. 7 refs., 8 figs., 9 tabs. (Author)

  9. Stream and Aquifer Biology of South-Central Texas - A Literature Review, 1973-97

    Science.gov (United States)

    2000-01-01

    on seed germination and seedling growth of Texas wild rice (Zizania texana): The Southwestern Naturalist, v. 40, no. 1, p. 1–4. Puente, Celso, 1974... Poaceae Zizania texana Araceae Pistia stratiotes Pontederiaceae Eichhornia crassipes Ceratophyllaceae Ceratophyllum demersum Heteranthera

  10. A 10 Billion MeV Cyclotron

    Science.gov (United States)

    Edge, R. D.

    1974-01-01

    Discusses the design of a device which serves to demonstrate the principle of acceleration and phase stability by accelerating gravitationally a ball bearing along a spiral groove. Application of the design principle to the acceleration aspect of a linear accelerator is recommended. (CC)

  11. Texas Occurrence of Lyme Disease and Its Neurological Manifestations.

    Science.gov (United States)

    Dandashi, Jad A; Nizamutdinov, Damir; Dayawansa, Samantha; Fonkem, Ekokobe; Huang, Jason H

    2016-06-01

    Today, Lyme disease is the most commonly reported tick-borne disease in the United States and Europe. The culprits behind Lyme disease are the Borrelia species of bacteria. In the USA, Borrelia burgdorferi causes the majority of cases, while in Europe and Asia Borrelia afzelii and Borrelia garinii carry the greatest burden of disease. The clinical manifestations of Lyme disease have been identified as early localized, early disseminated, and late chronic. The neurological effects of Lyme disease include both peripheral and central nervous systems involvement, including focal nerve abnormalities, cranial neuropathies, painful radiculoneuritis, meningitis, and/or toxic metabolic encephalopathy, known as Lyme encephalopathy. Given the geographic predominance of Lyme disease in the Northeast and Midwest of the USA, no major studies have been conducted regarding Southern states. Between 2005 and 2014, the Center for Disease Control has reported 582 confirmed cases of Lyme disease in Texas. Because of the potential for increased incidence and prevalence in Texas, it has become essential for research and clinical efforts to be diverted to the region. The Texas A&M College of Veterinary Medicine and Biomedical Sciences Lyme Lab has been investigating the ecology of Lyme disease in Texas and developing a pan-specific serological test for Lyme diagnosis. This report aimed to exposure materials and raise awareness of Lyme disease to healthcare providers.

  12. Experimental monitoring of ozone production in a PET cyclotron facility

    Energy Technology Data Exchange (ETDEWEB)

    Zanibellato, L. [Department of Energetic, Nuclear and Environmental Control, University of Bologna (Italy); Cicoria, G.; Pancaldi, D. [Department of Medical Physics, University Hospital ' S.Orsola-Malpighi' , Bologna (Italy); Boschi, S. [PET Radiopharmacy Unit, Department of Nuclear Medicine, University Hospital ' S.Orsola-Malpighi' , Bologna (Italy); Mostacci, D. [Department of Energetic, Nuclear and Environmental Control, University of Bologna (Italy); Marengo, M., E-mail: marengo@med.unibo.i [Department of Medical Physics, University Hospital ' S.Orsola-Malpighi' , Bologna (Italy)

    2010-10-15

    Ozone produced from radiolytic processes was investigated as a possible health hazard in the working environment at the University Hospital 'S.Orsola-Malpighi' PET facility. Intense radiation fields can generate ozone, known to be the most toxic gas produced by ionizing radiation around a particle accelerator. To evaluate ozone concentration in air, two different measurement campaigns were conducted with passive diffusion detectors. Comparison of the results with the concentration limits recommended by American Conference of Governmental Industrial Hygienists (ACGIH) demonstrated that ozone poses no health hazard to workers around a biomedical cyclotron.

  13. submitter Development of a Superconducting Magnet for a Compact Cyclotron for Radioisotope Production

    CERN Document Server

    Garcia-Tabares, Luis; Calero, Jesus; Gutierrez, Jose L; Munilla, Javier; Obradors, Diego; Perez, Jose M; Toral, Fernando; Iturbe, Rafael; Minguez, Leire; Gomez, Jose; Rodilla, Elena; Bajko, Marta; Michels, Matthias; Berkowitz, Daniel; Haug, Friedrich

    2016-01-01

    The present paper describes the development process of a low critical temperature superconducting magnet to be installed in a compact cyclotron producing single-dose radioisotopes for clinical and preclinical applications. After a brief description of the accelerator, the magnet development process is described, starting from the magnetic, mechanical, quench, and thermal calculations, continuing with the designing process, particularly the support structure of the magnet and the cryogenic supply system, to finish with the fabrication and the first tests than have been performed.

  14. Techniques and mechanisms applied in electron cyclotron resonance sources for highly charged ions

    NARCIS (Netherlands)

    Drentje, AG

    Electron cyclotron resonance ion sources are delivering beams of highly charged ions for a wide range of applications in many laboratories. For more than two decades, the development of these ion sources has been to a large extent an intuitive and experimental enterprise. Much effort has been spent

  15. Summary of EC-17: the 17th Joint Workshop on Electron Cyclotron Emission and Electron Cyclotron Resonance Heating (Deurne, The Netherlands, 7-10 May 2012)

    NARCIS (Netherlands)

    Westerhof, E.; Austin, M. E.; Kubo, S.; Lin-Liu, Y. R.; Plaum, B.

    2013-01-01

    An overview is given of the papers presented at the 17th Joint Workshop on Electron Cyclotron Emission (ECE) and Electron Cyclotron Resonance Heating (ECRH). The meeting covered all aspects of the research field ranging from theory to enabling technologies. From the workshop, advanced control by

  16. Embracing the local: enriching scientific research, education, and outreach on the Texas-Mexico border through a participatory action research partnership.

    Science.gov (United States)

    May, Marlynn L; Bowman, Gloria J; Ramos, Kenneth S; Rincones, Larry; Rebollar, Maria G; Rosa, Mary L; Saldana, Josephine; Sanchez, Adelina P; Serna, Teresa; Viega, Norma; Villegas, Gregoria S; Zamorano, Maria G; Ramos, Irma N

    2003-01-01

    Cameron Park, Texas, is a colonia (an isolated, unincorporated rural settlement without municipal improvements) on the Texas-Mexico border in the Lower Rio Grande Valley, in Cameron County near Brownsville, Texas. Cameron Park has a population of 5,961 residents, 99.3% of whom are Hispanic. The annual median income is 16,934 US dollars, about one-half of the state median. Fifty-eight percent of families generally and 68% of those with children younger than 5 years have incomes below poverty level. Cameron Park resides geographically in a region where agriculture has been, and continues to be, a dominant industry, a fact consistent with the intensive use of pesticides and increased potential for air, water, and ground contamination. The practice of good environmental health is extremely difficult under these conditions. In 1999 the Texas A&M University Center for Housing and Urban Development's Colonias Program and the Center for Environmental and Rural Health teamed up to create an environmental health education and outreach program called the Cameron Park Project (CPP). The CPP focused on how to reduce potential environmental exposures associated with human illness by providing residents with scientifically sound information on positive health practices and how to deal with environmental hazards. In this article we discuss the research methodology used in the CPP, a methodology specifically chosen to address four challenges presented by colonias to conducting valid and reliable research. PMID:14527834

  17. Electron cyclotron emission measurements on JET: Michelson interferometer, new absolute calibration, and determination of electron temperature

    NARCIS (Netherlands)

    Schmuck, S.; Fessey, J.; Gerbaud, T.; Alper, B.; Beurskens, M. N. A.; de la Luna, E.; Sirinelli, A.; Zerbini, M.

    2012-01-01

    At the fusion experiment JET, a Michelson interferometer is used to measure the spectrum of the electron cyclotron emission in the spectral range 70-500 GHz. The interferometer is absolutely calibrated using the hot/cold technique and, in consequence, the spatial profile of the plasma electron

  18. Studies on a Q/A selector for the SECRAL electron cyclotron resonance ion source.

    Science.gov (United States)

    Yang, Y; Sun, L T; Feng, Y C; Fang, X; Lu, W; Zhang, W H; Cao, Y; Zhang, X Z; Zhao, H W

    2014-08-01

    Electron cyclotron resonance ion sources are widely used in heavy ion accelerators in the world because they are capable of producing high current beams of highly charged ions. However, the design of the Q/A selector system for these devices is challenging, because it must have a sufficient ion resolution while controlling the beam emittance growth. Moreover, this system has to be matched for a wide range of ion beam species with different intensities. In this paper, research on the Q/A selector system at the SECRAL (Superconducting Electron Cyclotron Resonance ion source with Advanced design in Lanzhou) platform both in experiment and simulation is presented. Based on this study, a new Q/A selector system has been designed for SECRAL II. The features of the new design including beam simulations are also presented.

  19. CLOVERLEAF CYCLOTRON

    Science.gov (United States)

    McMillan, E.M.; Judd, D.L.

    1959-02-01

    A cyclotron is presented embodying a unique magnetic field configuration, which configuration increases in intensity with radius and therefore compensates for the reltivistic mass effect, the field having further convolutions productive of axial stability in the particle beam. By reconciling the seemingly opposed requirements of mass increase compensation on one hand and anial stability on the other, the production of extremely high current particle beams in the relativistie energy range is made feasible. Certain further advantages inhere in the invention, notably an increase in the usable magnet gap, simplified and more efficient extraction of the beam from the accelerator, and ready adaptation to the use of multiply phased excitation as contrasted with the single phased systems herstofore utilized. General

  20. East Texas harvest and utilization study, 2008

    Science.gov (United States)

    Rhonda M. Mathison; James W. Bentley; Tony G. Johnson

    2009-01-01

    In 2008, a harvest and utilization study was conducted on 80 operations throughout eastern Texas. There were 2,024 total trees measured: 1,335 or 66 percent were softwood, while 689 or 34 percent were hardwood. Results from this study showed that 86 percent of the total softwood volume measured was utilized for a product, and 14 percent was left as logging...

  1. A real-time intercepting beam-profile monitor for a medical cyclotron

    Science.gov (United States)

    Hendriks, C.; Uittenbosch, T.; Cameron, D.; Kellogg, S.; Gray, D.; Buckley, K.; Schaffer, P.; Verzilov, V.; Hoehr, C.

    2013-11-01

    There is a lack of real-time continuous beam-diagnostic tools for medical cyclotrons due to high power deposition during proton irradiation. To overcome this limitation, we have developed a profile monitor that is capable of providing continuous feedback about beam shape and current in real time while it is inserted in the beam path. This enables users to optimize the beam profile and observe fluctuations in the beam over time with periodic insertion of the monitor.

  2. A real-time intercepting beam-profile monitor for a medical cyclotron.

    Science.gov (United States)

    Hendriks, C; Uittenbosch, T; Cameron, D; Kellogg, S; Gray, D; Buckley, K; Schaffer, P; Verzilov, V; Hoehr, C

    2013-11-01

    There is a lack of real-time continuous beam-diagnostic tools for medical cyclotrons due to high power deposition during proton irradiation. To overcome this limitation, we have developed a profile monitor that is capable of providing continuous feedback about beam shape and current in real time while it is inserted in the beam path. This enables users to optimize the beam profile and observe fluctuations in the beam over time with periodic insertion of the monitor.

  3. Cyclotron-based neutron source for BNCT

    Energy Technology Data Exchange (ETDEWEB)

    Mitsumoto, T.; Yajima, S.; Tsutsui, H.; Ogasawara, T.; Fujita, K. [Sumitomo Heavy Industries, Ltd (Japan); Tanaka, H.; Sakurai, Y.; Maruhashi, A. [Kyoto University Research Reactor Institute (Japan)

    2013-04-19

    Kyoto University Research Reactor Institute (KURRI) and Sumitomo Heavy Industries, Ltd. (SHI) have developed a cyclotron-based neutron source for Boron Neutron Capture Therapy (BNCT). It was installed at KURRI in Osaka prefecture. The neutron source consists of a proton cyclotron named HM-30, a beam transport system and an irradiation and treatment system. In the cyclotron, H- ions are accelerated and extracted as 30 MeV proton beams of 1 mA. The proton beams is transported to the neutron production target made by a beryllium plate. Emitted neutrons are moderated by lead, iron, aluminum and calcium fluoride. The aperture diameter of neutron collimator is in the range from 100 mm to 250 mm. The peak neutron flux in the water phantom is 1.8 Multiplication-Sign 109 neutrons/cm{sup 2}/sec at 20 mm from the surface at 1 mA proton beam. The neutron source have been stably operated for 3 years with 30 kW proton beam. Various pre-clinical tests including animal tests have been done by using the cyclotron-based neutron source with {sup 10}B-p-Borono-phenylalanine. Clinical trials of malignant brain tumors will be started in this year.

  4. Finding the Common Ground: A Comparison of Writing Expectations and Outcomes between the Texas Essential Knowledge and Skills and the Common Core State Standards

    Science.gov (United States)

    Jacoby, Pat; Vasinda, Sheri

    2014-01-01

    In the Winter 2013 edition of the "Texas Journal of Literacy Education," we announced that a special task force from the TALE board would be sharing the common ground among the Texas Essential Knowledge and Skills (TEKS), Common Core State Standards (CCSS), and the College and Career Readiness Standards (CCRS). In that first edition, we…

  5. Cyclotron-based neutron source for BNCT

    Science.gov (United States)

    Mitsumoto, T.; Yajima, S.; Tsutsui, H.; Ogasawara, T.; Fujita, K.; Tanaka, H.; Sakurai, Y.; Maruhashi, A.

    2013-04-01

    Kyoto University Research Reactor Institute (KURRI) and Sumitomo Heavy Industries, Ltd. (SHI) have developed a cyclotron-based neutron source for Boron Neutron Capture Therapy (BNCT). It was installed at KURRI in Osaka prefecture. The neutron source consists of a proton cyclotron named HM-30, a beam transport system and an irradiation & treatment system. In the cyclotron, H- ions are accelerated and extracted as 30 MeV proton beams of 1 mA. The proton beams is transported to the neutron production target made by a beryllium plate. Emitted neutrons are moderated by lead, iron, aluminum and calcium fluoride. The aperture diameter of neutron collimator is in the range from 100 mm to 250 mm. The peak neutron flux in the water phantom is 1.8×109 neutrons/cm2/sec at 20 mm from the surface at 1 mA proton beam. The neutron source have been stably operated for 3 years with 30 kW proton beam. Various pre-clinical tests including animal tests have been done by using the cyclotron-based neutron source with 10B-p-Borono-phenylalanine. Clinical trials of malignant brain tumors will be started in this year.

  6. A Quantitative Research Investigation into High School Design and Art Education in a Local High School in Texas

    Science.gov (United States)

    Lin, Yi-Hsien

    2013-01-01

    This study was designed to explore the differences between high school teachers with art and science backgrounds in terms of curriculum and student performance in art and design education, federal educational policy, and financial support. The study took place in a local independent school district in Texarkana, Texas. The independent school…

  7. Acute toxicity and treatment interruption related to electron and photon craniospinal irradiation in pediatric patients treated at the University of Texas M. D. Anderson Cancer Center.

    Science.gov (United States)

    Chang, Eric L; Allen, Pamela; Wu, Catherine; Ater, Joann; Kuttesch, John; Maor, Moshe H

    2002-03-15

    To determine the incidence of acute toxicity and treatment interruption associated with electron and photon craniospinal irradiation (CSI) in children treated with or without chemotherapy. A retrospective study involving a computerized search of the radiotherapy database at the University of Texas M. D. Anderson Cancer Center identified a total of 79 eligible patients electron (n = 46) or photon (n = 33) CSI from October 1980 to March 2000. Acute toxicity was graded according to the 1998 National Cancer Institute Common Toxicity Criteria. Chemotherapy sequencing was categorized as before or after CSI or no chemotherapy. The incidences of weight loss and skin toxicity were recorded and differences in treatment interruption and hematologic values with respect to modality used (electron vs. photon), age (6 years), and sequencing of chemotherapy were compared using chi-square tests. The median age of the electron group was lower than that of the photon group (6.7 years and 11.7 years, respectively). The two groups were otherwise well matched in terms of median spinal dose (31.1 vs. 33.3 Gy), fraction size (1.57 vs. 1.63 Gy), and total treatment time (32.4 vs. 30.7 days). Only 2 patients in each group (photon and electron) had a treatment break (>3 days). The mean number of days interrupted was 0.94 (photon) and 1.1 (electron) (p = 0.72). The electron and photon groups were well balanced in terms of receiving pre-CSI chemotherapy (37% vs. 41%, p = 0.776). Chemotherapy given before radiotherapy vs. after or not at all was associated with an increased incidence of Grade 3-4 leukopenia (76% vs. 49%, p = 0.02), thrombocytopenia (90% vs. 10%, p = 0), and neutropenia (50% vs. 15%, p = 0.005). A younger age was associated with Grade 3-4 thrombocytopenia (29% vs. 8.7%, p = 0.034), and decreased hemoglobin (29% vs. 6.5%, p = 0.014). The incidence of leukocyte depression of Grade 3-4 toxicity was 62% in the electron group and 32% in the photon group (p = 0.018). The incidence of

  8. Production of high intensity 48Ca for the 88-Inch Cyclotron and other updates.

    Science.gov (United States)

    Benitez, J Y; Franzen, K Y; Hodgkinson, A; Lyneis, C M; Strohmeier, M; Thullier, T; Todd, D; Xie, D

    2014-02-01

    Recently the Versatile ECR for NUclear Science (VENUS) ion source was engaged in a 60-day long campaign to deliver high intensity (48)Ca(11+) beam to the 88-Inch Cyclotron. As the first long term use of VENUS for multi-week heavy-element research, new methods were developed to maximize oven to target efficiency. First, the tuning parameters of VENUS for injection into the cyclotron proved to be very different than those used to tune VENUS for maximum beam output of the desired charge state immediately following its bending magnet. Second, helium with no oxygen support gas was used to maximize the efficiency. The performance of VENUS and its low temperature oven used to produce the stable requested 75 eμA of (48)Ca(11+) beam current was impressive. The consumption of (48)Ca in VENUS using the low temperature oven was checked roughly weekly, and was found to be on average 0.27 mg/h with an ionization efficiency into the 11+ charge state of 5.0%. No degradation in performance was noted over time. In addition, with the successful operation of VENUS the 88-Inch cyclotron was able to extract a record 2 pμA of (48)Ca(11+), with a VENUS output beam current of 219 eμA. The paper describes the characteristics of the VENUS tune used for maximum transport efficiency into the cyclotron as well as ongoing efforts to improve the transport efficiency from VENUS into the cyclotron. In addition, we briefly present details regarding the recent successful repair of the cryostat vacuum system.

  9. Electron cyclotron wave sources and applications for fusion

    Science.gov (United States)

    Thomassen, K. I.

    1990-03-01

    Advances in magnetic fusion research have come as often from the use of new technologies as from the invention of ideas and discovery of phenomena that are then applied to new experiments. The technologies needed for plasma production, heating, confinement, and control have largely been developed and are a major factor in the success of our current experiments. These include high vacuum techniques, normal and superconducting magnets, particle beams, pellet fueling devices, and rf sources in the ion cylotron and lower hybrid range of frequencies. One area where development is especially required, and where the potential impact on fusion research is large, is that of electron cyclotron wave (ECW) sources in the 100-600 GHz range. This journal issue is devoted to methods for ECW generation and transmission, and to applications including heating, current drive, profile shaping, and instability control. To help focus these articles the requirements(1) for a system to heat the Compact Ignition Tokamak (CIT) were used to define the necessary technology. Somewhat lower frequencies, but similar power, is anticipated(2) for the International Thermonuclear Experimental Reactor (ITER), and for future large devices of that class, should they use ECW sources in them.

  10. BEST medical radioisotope production cyclotrons

    Energy Technology Data Exchange (ETDEWEB)

    Sabaiduc, Vasile; Milton, Bruce; Suthanthiran, Krishnan; Johnson, Richard R. [Best Cyclotron Systems Inc., 7-8765 Ash Street, Vancouver, British Columbia, V6P 6T3 (Canada); Gelbart, W. Z. [Advanced System Designs Inc., 5295 Bear Bay Road, Garden Bay, BC, V0N 1S1 (Canada)

    2013-04-19

    Best Cyclotron Systems Inc (BCSI) is currently developing 14 MeV, 25 MeV, 35MeV and 70MeV cyclotrons for radioisotope production and research applications as well as the entire spectrum of targets and nuclear synthesis modules for the production of Positron Emission Tomography (PET), Single Photon Emission Computed Tomography (SPECT) and radiation therapy isotopes. The company is a subsidiary of Best Medical International, renowned in the field of medical instrumentation and radiation therapy. All cyclotrons have external negative hydrogen ion sources, four radial sectors with two dees in opposite valleys, cryogenic vacuum system and simultaneous beam extraction on opposite lines. The beam intensity ranges from 400 {mu}A to 1000 {mu}A, depending on the cyclotron energy and application.

  11. Forests of East Texas, 2014

    Science.gov (United States)

    Thomas J. Brandeis

    2015-01-01

    This resource update provides an overview of forest resources in east Texas derived from an inventory conducted by the U.S. Forest Service, Forest Inventory and Analysis (FIA) Program at the Southern Research Station in cooperation with the Texas A&M Forest Service. These estimates are based on field data collected using the FIA annualized sample design and are...

  12. Texas motorcycle crash countermeasure workshop.

    Science.gov (United States)

    2013-06-01

    The Texas Department of Transportation (TxDOT) contracted with the Texas A&M : Transportation Institute (TTI) to develop a 5-year strategic plan for improving motorcycle safety : in the State of Texas. The Texas Strategic Action Plan for Motorcycl...

  13. Understanding the bursty electron cyclotron emission during a sawtooth crash in the HT-7 tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Li, Erzhong, E-mail: rzhonglee@ipp.ac.cn; Hu, Liqun; Chen, Kaiyun [Institute of Plasma Physics, Chinese Academy of Science, Hefei 230031 (China)

    2014-01-15

    Bursts in electron cyclotron emission (ECE) were observed during sawtooth crashes in HT-7 in discharges with ion cyclotron resonance heating injected near the q = 1 rational surface (q is the safety factor). The local ECE measurement indicated that the bursty radiation is only observed on channels near but a little away outward from the q = 1 magnetic surface. In conjunction with the soft x-ray tomography analysis, it was determined that, for the first time, only a compression process survives in the later stage of fast magnetic reconnection but before prompt heat transport. The compression enhanced the electron radiation temperature, the increased amplitude of which agreed well with the estimation according to a kinetic compression theory model [R. J. Hastie and T. C. Hender, Nucl. Fusion 28, 585 (1988)]. This paper presents the experimental evidence that there indeed exists a transient compression phase which results in the bursty ECE radiation during a sawtooth crash.

  14. Understanding the bursty electron cyclotron emission during a sawtooth crash in the HT-7 tokamak

    Science.gov (United States)

    Li, Erzhong; Hu, Liqun; Chen, Kaiyun

    2014-01-01

    Bursts in electron cyclotron emission (ECE) were observed during sawtooth crashes in HT-7 in discharges with ion cyclotron resonance heating injected near the q = 1 rational surface (q is the safety factor). The local ECE measurement indicated that the bursty radiation is only observed on channels near but a little away outward from the q = 1 magnetic surface. In conjunction with the soft x-ray tomography analysis, it was determined that, for the first time, only a compression process survives in the later stage of fast magnetic reconnection but before prompt heat transport. The compression enhanced the electron radiation temperature, the increased amplitude of which agreed well with the estimation according to a kinetic compression theory model [R. J. Hastie and T. C. Hender, Nucl. Fusion 28, 585 (1988)]. This paper presents the experimental evidence that there indeed exists a transient compression phase which results in the bursty ECE radiation during a sawtooth crash.

  15. Offender and victim characteristics of registered female sexual offenders in Texas: a proposed typology of female sexual offenders.

    Science.gov (United States)

    Vandiver, Donna M; Kercher, Glen

    2004-04-01

    Victim and offender characteristic of all registered adult female sexual offenders in Texas (N = 471) were examined. The most common offenses the females were arrested for were indecency with a child--sexual contact, sexual assault on a child, and aggravated sexual assault on a child. The majority (88%) of the females were Caucasian and the ages ranged from 18 to 77 (M = 32). The results of Hierarchical Loglinear Modeling yielded a complex relationship between offender and victim characteristics; thus, identification of preferred victims is mitigated by more than one variable. Additionally, the employment of cluster analysis yielded 6 types of female sexual offenders. The most common group includes 146 offenders, heterosexual nurturers. They were the least likely to have an arrest for a sexual assault. The victims were males who averaged 12 years of age. The other types of offenders included, noncriminal homosexual offenders, female sexual predators, young adult child exploiters, homosexual criminals, and aggressive homosexual offenders.

  16. 76 FR 12683 - Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition To List the Texas...

    Science.gov (United States)

    2011-03-08

    ... banner-tailed kangaroo rat (D. spectabilis) based on general external morphology (body structure) and...; Nelson et al. 2009, pp. 128-129). Texas kangaroo rats primarily feed on grass seeds (Chapman 1972, pp. 878-879). However, the seeds, leaves, fruits, and flowers of annual forbs may also be a significant...

  17. A Study of Boards of Education in Texas -- the Makeup of Boards and the Perceptions of Board Members. Studies in Education XI.

    Science.gov (United States)

    Splawn, Robert E.

    This study is based on the results of a background questionnaire and a perception inventory administered to a stratified random sample of Texas boards of education members in independent school districts having grades K-12. The study attempted to determine (1) the status of Texas school boards, (2) the role of the board and the roles of the…

  18. The design of a correlation electron cyclotron emission system on J-TEXT

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Z. J.; Xiao, Y.; Ma, X. D.; Pan, X. M.; Xiao, J. S. [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, School of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2015-04-15

    To study the anomalous transport, a correlation electron cyclotron emission (CECE) was planned to be developed on J-TEXT for electron temperature fluctuation measurement. The spectral decorrelation method was employed for the CECE system. It was developed based on the previous 16-channel electron cyclotron emission system. They shared the optical transmission line and mixer. The CECE part consists of 4 channels. Two fixed frequency narrow band filters were used for two channels and two yttrium iron garnet (YIG) filters for the other two channels. To meet the measuring requirement, some tests have been taken for the YIG filters. The results show good performance of the filters. Gaussian optics is used to produce a good poloidal resolution. Wavenumbers resolved by the CECE diagnostic are k{sub θ} ≤ 1.5 rad/cm and k{sub r} ≤ 12 rad/cm. Some preliminary experiment results are also presented in this paper.

  19. Studies of extraction and transport system for highly charged ion beam of 18 GHz superconducting electron cyclotron resonance ion source at Research Center for Nuclear Physics.

    Science.gov (United States)

    Yorita, T; Hatanaka, K; Fukuda, M; Ueda, H; Yasuda, Y; Morinobu, S; Tamii, A; Kamakura, K

    2014-02-01

    An 18 GHz superconducting electron cyclotron resonance ion source is installed to increase beam currents and to extend the variety of ions especially for highly charged heavy ions which can be accelerated by cyclotrons of Research Center for Nuclear Physics (RCNP), Osaka University. The beam production developments of several ions from B to Xe have been already done [T. Yorita, K. Hatanaka, M. Fukuda, M. Kibayashi, S. Morinobu, H.Okamura, and A. Tamii, Rev. Sci. Instrum. 79, 02A311 (2008) and T. Yorita, K. Hatanaka, M. Fukuda, M. Kibayashi, S. Morinobu, H.Okamura, and A. Tamii, Rev. Sci. Instrum. 81, 02A332 (2010)] and the further studies for those beam extraction and its transport have been done in order to increase the beam current more. The plasma electrode, extraction electrode, and einzel lens are modified. Especially extraction electrode can be applied minus voltage for the beam extraction and it works well to improve the extracted beam current. The extraction voltage dependences of transmission and emittance also have been studied for beam current improvement which is injected into azimuthally varying field cyclotron at RCNP.

  20. The Texas Earth and Space Science (TXESS) Revolution: A Model for the Delivery of Earth Science Professional Development to Minority-Serving Teachers

    Science.gov (United States)

    Ellins, K. K.; Snow, E.; Olson, H. C.; Stocks, E.; Willis, M.; Olson, J.; Odell, M. R.

    2013-01-01

    The Texas Earth and Space Science (TXESS) Revolution was a 5-y teacher professional development project that aimed to increase teachers' content knowledge in Earth science and preparing them to teach a 12th-grade capstone Earth and Space Science course, which is new to the Texas curriculum. The National Science Foundation-supported project was…

  1. Cherenkov-cyclotron instability in a metamaterial loaded waveguide for high power generation

    Science.gov (United States)

    Lu, Xueying; Shapiro, Michael; Temkin, Richard

    2017-10-01

    This work presents the analytical theory for an S-band high power microwave experiment at MIT utilizing a metamaterial (MTM) structure. A 490 kV, 84 A electron beam travels through a rectangular waveguide loaded with two MTM plates in a DC magnetic field B0. The excited waveguide mode is deflecting with a transverse E field on beam axis. Microsecond long megawatt level microwave pulses were generated under a low B0 in the Cherenkov-cyclotron type of interaction. A linear theory has been developed to explain the high power generation due to the Cherenkov-cyclotron instability. The simplified model is a planar waveguide filled with a double negative dispersive medium, and in the mode being studied, the longitudinal E field has an antisymmetric pattern in the direction perpendicular to the MTM plates. We have proved that the Cherenkov-cyclotron instability can happen with a zero initial transverse beam velocity when B0 is below a threshold. Also this instability is a unique feature of the left-handed MTM, since it requires a propagating mode below the cut-off frequency. The minimum beam current to start the instability is calculated, and the scaling law different from that of the traditional backward wave oscillators operated by longitudinal bunching will be discussed. This research was supported by the Air Force Office of Scientific Research within the Multidisciplinary University Research Initiative under Grant No. FA9550-12-1-0489 through the University of New Mexico.

  2. Cyclotron for Beam Therapy Application

    CERN Document Server

    Alenitsky, Yu G; Karamysheva, G A; Kostromin, S A; Mitsyn, G V; Molokanov, A G; Onishchenko, L M; Samsonov, E V; Vorozhtsov, S B; Zaplatin, N L

    2005-01-01

    The basic parameters of the proton isochronous cyclotron on the fixed energy are considered. The energy of protons is $E_{p}\\sim $ 220~MeV, intensity of the extracted beam is $I_{p}\\sim $ 0.1~$\\mu$A. The cyclotron is projected on the basis of compact magnet with four sectors and the diameter of poles 300 cm. Two dees of the accelerating system are located in valleys.

  3. Development, calibration, and validation of performance prediction models for the Texas M-E flexible pavement design system.

    Science.gov (United States)

    2010-08-01

    This study was intended to recommend future directions for the development of TxDOTs Mechanistic-Empirical : (TexME) design system. For stress predictions, a multi-layer linear elastic system was evaluated and its validity was : verified by compar...

  4. Review on production of 89Zr in a medical cyclotron for PET radiopharmaceuticals.

    Science.gov (United States)

    Kasbollah, Azahari; Eu, Peter; Cowell, Simon; Deb, Pradip

    2013-03-01

    This article is intended to provide an overview of the production and application of (89)Zr for the professional development of nuclear medicine technologists. It outlines the cyclotron targeting, separation and labeling options, and techniques for the preparation of the radionuclide (89)Zr (half-life, 78.4 h [3.3 d]) used in PET. Unlike the commonly used (18)F-FDG, with a 109.7-min half-life, the longer half-life of (89)Zr makes it possible to use high-resolution PET/CT to localize and image tumors with monoclonal antibody radiopharmaceuticals and thus potentially expand the use of PET. This paper briefly reviews the cyclotron technique of (89)Zr production and outlines the range and preparation techniques available for making (89)Y targets as a starting material. It then discusses how cyclotron-produced (89)Zr can be separated, purified, and labeled to monoclonal antibodies for PET/CT of specific tumors. We argue that knowledge and understanding of this long-lived PET radionuclide should be part of the professional development of nuclear medicine technologists because it will lead to better patient outcomes and potentially increase the pool of collaborators in this field of research.

  5. Laboratory and cyclotron requirements for PET research

    Energy Technology Data Exchange (ETDEWEB)

    Schlyer, D.J.

    1993-06-01

    This report describes four types of PET facilities: Clinical PET with no radionuclide production; clinical PET with a small accelerator; clinical PET with research support; and research PET facilities. General facility considerations are also discussed.

  6. Electron Cloud Cyclotron Resonances in the Presence of a Short-bunch-length Relativistic Beam

    Energy Technology Data Exchange (ETDEWEB)

    Celata, C.M.; Furman, Miguel A.; Vay, J.-L.; Yu, Jennifer W.

    2008-09-02

    Computer simulations using the 2D code"POSINST" were used to study the formation of the electron cloud in the wiggler section of the positron damping ring of the International Linear Collider. In order to simulate an x-y slice of the wiggler (i.e., a slice perpendicular to the beam velocity), each simulation assumed a constant vertical magnetic field. At values of the magnetic field where the cyclotron frequency was an integral multiple of the bunch frequency, and where the field strength was less than approximately 0.6 T, equilibrium average electron densities were up to three times the density found at other neighboring field values. Effects of this resonance between the bunch and cyclotron frequency are expected to be non-negligible when the beam bunch length is much less than the product of the electron cyclotron period and the beam velocity, for a beam moving at v~;;c. Details of the dynamics of the resonance are described.

  7. Adult Community Orchestras in Texas: Activity and Background Profiles of Participants with a Report of Organizational Standing

    Science.gov (United States)

    Brown, Kathryn Dharlene

    2016-01-01

    The purpose of this study was to identify and assess Texas community orchestras and create a demographic and musical profile of participants. This was accomplished through use of two online questionnaires. A director survey questionnaire determined the organizational status of each orchestra. The directors surveyed were leaders in these…

  8. Collision cross section measurements for biomolecules within a high-resolution Fourier transform ion cyclotron resonance cell.

    Science.gov (United States)

    Mao, Lu; Chen, Yu; Xin, Yi; Chen, Yu; Zheng, Li; Kaiser, Nathan K; Marshall, Alan G; Xu, Wei

    2015-04-21

    To understand the role and function of a biomolecule in a biosystem, it is important to know both its composition and structure. Here, a mass spectrometric based approach has been proposed and applied to demonstrate that collision cross sections and high-resolution mass spectra of biomolecule ions may be obtained simultaneously by Fourier transform ion cyclotron resonance mass spectrometry. With this method, the unfolding phenomena for ubiquitin ions that possess different number of charges have been investigated, and results agree well with ion mobility measurements. In the present approach, we extend ion collision cross-section measurements to lower pressures than in prior ion cyclotron resonance (ICR)-based experiments, thereby maintaining the potentially high resolution of Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS), and enabling collision cross section (CCS) measurements for high-mass biomolecules.

  9. Development of a medical humanities and ethics certificate program in Texas.

    Science.gov (United States)

    Erwin, Cheryl J

    2014-12-01

    Education in the medical humanities and ethics is an integral part of the formation of future physicians. This article reports on an innovative approach to incorporating the medical humanities and ethics into the four-year curriculum in a Certificate Program spanning all four years of the medical school experience. The faculty of the McGovern Center for Humanities and Ethics at the University of Texas Medical School at Houston conceived and implemented this program to teach medical students a range of scholarly topics in the medical humanities and to engage the full human experience into the process of becoming a physician. This study follows six years of experience, and we report student experiences and learning in their own words.

  10. Cyclotron-produced radioisotopes and their clinical use at the Austin PET Centre

    Energy Technology Data Exchange (ETDEWEB)

    Tochon-Danguy, H.J. [Centre for PET, Melbourne, VIC (Australia). Austin and Repatriation Medical Centre

    1997-12-31

    A Centre for Positron Emission Tomography (PET) has been established within the Department of Nuclear Medicine at the Austin and Repatriation Medical Centre in Melbourne. PET is a non-invasive technique based on the use of biologically relevant compounds labelled with short-lived positron-emitting radionuclides such as carbon-11, nitrogen-13, oxygen-15 and fluorine-18. The basic equipment consists of a medical cyclotron (10 MeV proton and 5 MeV deuteron), six lead-shielded hot cells with associated radiochemistry facilities and a whole body PET scanner. During its first five years of operation, the Melbourne PET Centre, has pursued a strong radiolabelling development program, leading to an ambitious clinical program in neurology, oncology and cardiology. This presentation will describe the basic principles of the PET technique and review the cyclotron-produced radioisotopes and radiopharmaceuticals. Radiolabelling development programs and clinical applications are also addressed. 30 refs., 1 tab., 1 fig.

  11. 76 FR 62165 - Endangered and Threatened Wildlife and Plants; 12-Month Finding on a Petition To List Texas...

    Science.gov (United States)

    2011-10-06

    ... release clouds of sperm into the water column, which females draw in through their siphons. Fertilization... created by artificial impoundments. Distribution and Abundance Historical Distribution The Texas fatmucket...

  12. The accuracy of heavy-ion mass measurements using time of flight-ion cyclotron resonance in a Penning trap

    Science.gov (United States)

    Bollen, G.; Moore, R. B.; Savard, G.; Stolzenberg, H.

    1990-11-01

    Ion motion in a Penning trap and the electrical signals it can produce have been analyzed for the purpose of identifying the important causes of uncertainty in high-accuracy mass measurements of heavy ions. The role of the azimuthal quadrupole electric field in signal pickup, and its effects on ion motion at the sum frequency of the cyclotron and magnetron motions, have been identified. A useful scheme for calculating the signal strength and strength of the interaction between an applied field and the ion motion has been developed. The important sources of uncertainty in using the sum frequency of the cyclotron and magnetron motions for determining the ion mass are discussed. Particular application is made to the case of cyclotron resonance detection by observation of the time of flight of ejected ions.

  13. Demographic Changes of Hispanic Populations and Hispanic Student Enrollment in Texas Community Colleges: A Literature Review

    Science.gov (United States)

    Hernandez, Jack; Slate, John R.; Joyner, Sheila A.

    2015-01-01

    In this literature review, Hispanic demographic changes in the United States and in Texas are examined. Hispanics have accounted for large changes in population, population change, and proportion of population. Accordingly, the literature was reviewed regarding Hispanic immigrants, both authorized and non-authorized immigrants. The issue of…

  14. A CW radiofrequency ion source for production of negative hydrogen ion beams for cyclotrons

    Energy Technology Data Exchange (ETDEWEB)

    Kalvas, T.; Tarvainen, O.; Komppula, J.; Koivisto, H.; Tuunanen, J. [University of Jyväskylä, Department of Physics (Finland); Potkins, D.; Stewart, T.; Dehnel, M. P. [D-Pace, Inc., Nelson, B.C. Canada (Canada)

    2015-04-08

    A CW 13.56 MHz radiofrequency-driven ion source RADIS for production of H{sup −} and D{sup −} beams is under development for replacing the filament-driven ion source of the MCC30/15 cyclotron. The RF ion source has a 16-pole multicusp plasma chamber, an electromagnet-based magnetic filter and an external planar spiral RF antenna behind an AlN window. The extraction is a 5-electrode system with an adjustable puller electrode voltage for optimizing the beam formation, a water-cooled electron dump electrode and an accelerating einzel lens. At 2650 W of RF power, the source produces 1 mA of H{sup −} (2.6 mA/cm{sup 2}), which is the intensity needed at injection for production of 200 µA H{sup +} with the filament-driven ion source. A simple pepperpot device has been developed for characterizing the beam emittance. Plans for improving the power efficiency with the use of a new permanent magnet front plate is discussed.

  15. Groundwater Challenges of the Lower Rio Grande: A Case Study of Legal Issues in Texas and New Mexico

    Directory of Open Access Journals (Sweden)

    Elizabeth Wheat

    2015-03-01

    Full Text Available In 1938, Texas, New Mexico, and Colorado signed the Rio Grande Compact, establishing terms of apportionment for some of the water from the Rio Grande for the three states. Following congressional approval in 1939, this compact governs water allocation in a region with a variable climate and frequent drought conditions and established the Rio Grande Compact Commission, comprised of a commissioner from each state and one from the federal government, to enforce the compact. With an increasing population and declining surface water supply, the Compact has been tested among the parties and within the states themselves. In a case currently before the U.S. Supreme Court, Texas v. New Mexico and Colorado (2013, Texas claims New Mexico is violating the Compact and Rio Grande Project Act by using water in excess of its apportionment through its allowance of diversions of surface and groundwater. The issue is further compounded by disputes within Texas over separate legal regimes for groundwater and surface water. Combined with growing scarcity issues, the allocation of water in the Lower Rio Grande presents a timely natural resource challenge. This review explores legal issues involved in the case as well as growing challenges of population growth, agricultural development needs, and water shortages.

  16. Education Outreach Associated with Technology Transfer in a Colonia of South Texas: Green Valley Farms Science and Space Club for Middle School Aged Children in Green Valley Farms, San Benito, Texas

    Science.gov (United States)

    Potess, Marla D.; Rainwater, Ken; Muirhead, Dean

    2004-01-01

    Texas colonias are unincorporated subdivisions characterized by inadequate water and wastewater infrastructure, inadequate drainage and road infrastructure, substandard housing, and poverty. Since 1989 the Texas Legislature has implemented policies to halt further development of colonias and to address water and wastewater infrastructure needs in existing and new colonias along the border with Mexico. Government programs and non-government and private organization projects aim to address these infrastructure needs. Texas Tech University's Water Resources Center demonstrated the use of alternative on-site wastewater treatment in the Green Valley Farms colonia, San Benito, Texas. The work in Green Valley Farms was a component of a NASA-funded project entitled Evaluation of NASA's Advanced Life Support Integrated Water Recovery System for Non-Optimal Conditions and Terrestrial Applications. Two households within the colonia are demonstration sites for constructed wetlands. A colonia resident and activist identified educational opportunities for colonia children as a primary goal for many colonia residents. Colonia parents view education as the door to opportunity and escape from poverty for their children. The educational outreach component of the project in Green Valley Farms was a Science and Space Club for middle-school age students. Involved parents, schoolteachers, and school administrators enthusiastically supported the monthly club meetings and activities. Each month, students participated in interactive learning experiences about water use and reuse in space and on earth. Activities increased knowledge and interest in water resource issues and in science and engineering fields. The Institute for the Development and Enrichment of Advanced Learners (IDEAL) at Texas Tech University provided full scholarships for five students from Green Valley Farms to attend the Shake Hands With Your Future camp at Texas Tech University in June 2003. The educational outreach

  17. The Association between Sensation Seeking and E-Cigarette Use in Texas Young Adults: A Cross-Sectional Study

    Science.gov (United States)

    Case, Kathleen R.; Loukas, Alexandra; Harrell, Melissa B.; Wilkinson, Anna V.; Springer, Andrew E.; Pérez, Adriana; Creamer, MeLisa R.; Perry, Cheryl L.

    2017-01-01

    Objective: To examine the associations between sensation seeking and ever and current e-cigarette use in Texas young adults (18-29 years old). Current cigarette use was examined as a potential effect modifier of the associations. Participants: Participants included college students enrolled in four-year and two-year colleges in four metropolitan…

  18. "Chicano Empowerment and Bilingual Education: Movimiento Politics in Crystal City, Texas," by A. Trujillo (1998). Book Review.

    Science.gov (United States)

    Valenzuela, Angela

    2000-01-01

    Reviews a book that analyzes the 1970s political takeover of the Crystal City (Texas) school board, city council, and county offices by radical Chicano activists; district-wide establishment of maintenance bilingual education; internal and community divisions that followed; and eventual abandonment of the innovative programs. Points out the links…

  19. Through the Looking Glass: A Comparative Analysis of the Career Patterns of Rural Female Administrators in Saskatchewan and Texas

    Science.gov (United States)

    Wallin, Dawn C.

    2005-01-01

    This article stems from research that examined the effect of the rural context on the career patterns of female administrators in rural public school divisions in the province of Saskatchewan, Canada, and in the state of Texas, United States. These two studies examined (a) the nature of rural communities and its relationship to women's career…

  20. Incarceration and Adult Felon Probation in Texas: A Cost Comparison. Criminal Justice Monograph. Volume IV, Number 3.

    Science.gov (United States)

    Fraizer, Robert Lee; And Others

    In attempting to determine the cost of probation and the cost of incarceration of adult felons in Texas, it was discovered that there were no comparative figures available. A search of the literature was conducted to determine the proper standards for probation caseload management and to identify problems associated with previous cost studies. In…

  1. Excitation functions and yields for cyclotron production of radiorhenium via deuteron irradiation. {sup nat}W(d,xn){sup 181,182,(A+B),183,184(m+g),186g}Re nuclear reactions and tests on the production of {sup 186g}Re using enriched {sup 186}W

    Energy Technology Data Exchange (ETDEWEB)

    Manenti, Simone; Persico, Elisa; Bonardi, Mauro L.; Gini, Luigi; Groppi, Flavia [LASA, Univ. degli Studi di Milano, Segrate (Italy); INFN Milano (Italy); Abbas, Kamel; Holzwarth, Uwe; Simonelli, Federica [Institute for Health and Consumer Protection, IHCP, JRC-Ispra, Ispra (Italy)

    2014-10-01

    Excitation functions, thin- and thick-target yields for the {sup 181-186g}Re and {sup 187}W radionuclides were measured by the activation stacked-foil technique on natural tungsten foils for deuteron energies up to 18.0 MeV. These cross sections were validated by comparing the experimental results for thick-target yields with those calculated by integration of the thin-target yields. It was found that the maximum {sup 186g}Re content by irradiation of natural tungsten is about 55%, a higher value compared with the one found for proton beam, but not sufficient to use natural tungsten for medical purposes yet. Thus, in order to have a higher specific activity A{sub S} of {sup 186g}Re, the use of enriched {sup 186}W target is necessary. Therefore the irradiation of a thick target of enriched {sup 186}W by accelerated deuterons was studied and the results for the production of {sup 186g}Re were compared with those obtained from the irradiation of the same target by accelerated protons. It was found that the deuteron irradiation is preferable for three reasons: larger yield, less contamination by tantalum radioisotopes and smaller required amount of the target, which simplify the separation of the {sup 186g}Re from the target itself.

  2. Seminar | Development of a PET Cyclotron Based Irradiation Setup for Proton Radiobiology | 25 June

    CERN Multimedia

    2015-01-01

    Sharif Hasan Mahmoud Ghithan, a Palestinian postdoctoral researcher at the Laboratory of Instrumentation and Experimental Particle Physics (Portugal), will discuss the development of an out-of-yoke irradiation setup using the proton beam from a cyclotron that ordinarily produces radioisotopes for Positron Emission Tomography (PET). The speaker will also discuss possible future use of the results of this research for CERN’s new LEIR biomedical facility. The seminar will be proposed in the framework of a meeting of the CERN Medical Applications Study Group.   25 June, 2 p.m. to 3 p.m. Room 13-2-005 ABSTRACT: In this new irradiation setup, the current from a 20 mm thick aluminum transmission foil is read out by homemade transimpedance electronics, providing online dose information. The main monitoring variables, delivered in real-time, include beam current, integrated charge and dose rate. Hence the dose and integrated current delivered at a given instant to an experimental setu...

  3. Developing the smallest possible medical cyclotron

    CERN Multimedia

    Katarina Anthony

    2011-01-01

    Imagine a portable medical cyclotron operated in a conventional radioactive facility at a hospital. Imagine a nurse or technician switching it on and producing isotopes at the patient’s bedside. Sounds like science fiction? Think again.   CERN has teamed up with Spain’s national scientific research centre (CIEMAT) to develop an avant-garde cyclotron to be used for Positron Emission Tomography (PET). “We plan to make a cyclotron that doesn't need an insulated building or ‘vault’: a cyclotron small enough to fit inside a hospital lift,” explains Jose Manuel Perez, who is leading the CIEMAT/CERN collaboration. “It will be the smallest possible medical cyclotron for single patient dose production and will dramatically reduce costs for hospitals.” While PET technology has transformed imaging techniques, many of its medical benefits have remained confined to highly specialised hospitals. “Studies have foun...

  4. Was everything bigger in Texas? Characterization and trends of a land-based recreational shark fishery

    Science.gov (United States)

    Ajemian, Matthew J.; Jose, Philip D.; Froeschke, John T.; Wildhaber, Mark L.; Stunz, Gregory W.

    2016-01-01

    Although current assessments of shark population trends involve both fishery-independent and fishery-dependent data, the latter are generally limited to commercial landings that may neglect nearshore coastal habitats. Texas has supported the longest organized land-based recreational shark fishery in the United States, yet no studies have used this “non-traditional” data source to characterize the catch composition or trends in this multidecadal fishery. We analyzed catch records from two distinct periods straddling heavy commercial exploitation of sharks in the Gulf of Mexico (historical period = 1973–1986; modern period = 2008–2015) to highlight and make available the current status and historical trends in Texas’ land-based shark fishery. Catch records describing large coastal species (>1,800 mm stretched total length [STL]) were examined using multivariate techniques to assess catch seasonality and potential temporal shifts in species composition. These fishery-dependent data revealed consistent seasonality that was independent of the data set examined, although distinct shark assemblages were evident between the two periods. Similarity percentage analysis suggested decreased contributions of Lemon Shark Negaprion brevirostris over time and a general shift toward the dominance of Bull Shark Carcharhinus leucas and Blacktip Shark C. limbatus. Comparisons of mean STL for species captured in historical and modern periods further identified significant decreases for both Bull Sharks and Lemon Sharks. Size structure analysis showed a distinct paucity of landed individuals over 2,000 mm STL in recent years. Although inherent biases in reporting and potential gear-related inconsistencies undoubtedly influenced this fishery-dependent data set, the patterns in our findings documented potential declines in the size and occurrence of select large coastal shark species off Texas, consistent with declines reported in the Gulf of Mexico. Future management efforts

  5. Deployment Area Selection and Land Withdrawal/Acquisition. M-X/MPS (M-X/Multiple Protective Shelter) Environmental Technical Report. Native Americans Texas/New Mexico.

    Science.gov (United States)

    1981-10-02

    headwaters of the Brazos. In 1683 a great battle on the plains east of the Pecos River was fought between Apaches and Cebollas (Indian bison hunters...line of settlement. The final treaty with Comanches, Kiowas, and Kiowa Apaches was signed at Medicine Lodge, Kansas, in 1867. It restricted them to an...310). The pacification of the Comanche, Kiowa, and Kiowa Apache did not end with the signing of the Medicine Lodge treaty. Not all went to the

  6. Texas School Dropout Survey: A Report to the 69th Legislature, State of Texas.

    Science.gov (United States)

    Texas State Dept. of Community Affairs, Austin. Training and Employment Development Div.

    As a response to legislative demands, the Texas School Dropout Survey described in this document attempted to identify the magnitude of the dropout problem, regional characteristics or causes of the problem, costs associated with dropping out, and programs currently available for serving the dropout population. Twenty-four major findings of the…

  7. 78 FR 56071 - Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for Texas Golden...

    Science.gov (United States)

    2013-09-11

    ... local Soil and Water Conservation District, NRCS, Texas Forest Service, a private forestry services... critical habitat designation for the Texas golden gladecress would be an improvement to conservation... and Threatened Wildlife and Plants; Designation of Critical Habitat for Texas Golden Gladecress and...

  8. Ion cyclotron and spin-flip emissions from fusion products in tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Arunasalam, V.; Greene, G.J.; Young, K.M.

    1993-02-01

    Power emission by fusion products of tokamak plasmas in their ion cyclotron range of frequencies (ICRF) and at their spin-flip resonance frequency is calculated for some specific model fusion product velocity-space distribution functions. The background plasma of say deuterium (D) is assumed to be in equilibrium with a Maxwellian distribution both for the electrons and ions. The fusion product velocity distributions analyzed here are: (1) A monoenergetic velocity space ring distribution. (2) A monoenergetic velocity space spherical shell distribution. (3) An anisotropic Maxwellian distribution with T {perpendicular} {ne} T{parallel}and with appreciable drift velocity along the confining magnetic field. Single ``dressed`` test particle spontaneous emission calculations are presented first and the radiation temperature for ion cyclotron emission (ICE) is analyzed both for black-body emission and nonequilibrium conditions. Thresholds for instability and overstability conditions are then examined and quasilinear and nonlinear theories of the electromagnetic ion cyclotron modes are discussed. Distinctions between ``kinetic or causal instabilities`` and ``hydrodynamic instabilities`` are drawn and some numerical estimates are presented for typical tokamak parameters. Semiquantitative remarks are offered on wave accessibility, mode conversion, and parametric decay instabilities as possible for spatially localized ICE. Calculations are carried out both for k{parallel} = 0 for k{parallel} {ne} 0. The effects of the temperature anisotropy and large drift velocities in the parallel direction are also examined. Finally, proton spin-flip resonance emission and absorption calculations are also presented both for thermal equilibrium conditions and for an ``inverted`` population of states.

  9. Optical imaging of irradiated cyclotron target window foils using Cerenkov and radioluminescence imaging

    Science.gov (United States)

    Spinelli, A. E.; Boschi, F.; Calandrino, R.

    2017-05-01

    Radioisotopes production for PET radiopharmaceuticals is performed using cyclotrons resulting in radio activation of different cyclotron components. It is thus necessary to measure the level of radiation exposure and, if possible, to image the areas where most of the radiations are emitted in particular during maintenance or decommissioning procedures. In this work we present a novel optical imaging approach using Cerenkov luminescence imaging (CLI) and radioluminescence imaging (RLI). CLI was performed by placing a glass Cerenkov radiator on a target window (Havar foils) and RLI data were obtained by covering the Havar foils with an intensifying screen. CLI or RLI were acquired using a small animal optical imaging system used in bioluminescence mode without the use of any optical filters. The analysis of the normalized radiance line profiles of both CLI and RLI images showed a similar pattern, however the absolute radiance of the RLI signal is several order of magnitude higher with respect to CLI. We conclude that optical imaging with CLI and RLI can be considered a novel method to detect and image activation areas in irradiated samples from a medical cyclotron.

  10. Cyclotron production of the 105,106mAg, 100,101Pd, 100,101m,105Rh radionuclides by natPd(p,x) nuclear processes

    Science.gov (United States)

    Khandaker, Mayeen Uddin; Kim, Kwangsoo; Kim, Guinyun; Otuka, Naohiko

    2010-07-01

    Production cross-sections of the 105g+m,106mAg, 100,101Pd, and 100g+m,101m,105g+mRh radionuclides through proton-induced reactions on natural palladium were measured up to 40 MeV by using a stacked-foil activation technique combined with high-resolution γ-ray spectrometry. The production cross-sections of 101Pd and 100g+m,105g+mRh radionuclides have been reported here for the first time from the natPd(p,x) nuclear processes. The present results are compared with the available literature values as well as the theoretical data calculated by the TALYS and the ALICE-IPPE computer codes. A quantitative comparison of the present results with the theoretical data has also been done with several deviation factor definitions. Optimal production pathways of the therapeutic 105gRh radionuclide with minimal contamination using cyclotrons are discussed elaborately.

  11. Subsequent radical fragmentation reactions of N, N-diethylamino-substituted azobenzene derivatives in a Fourier transform ion cyclotron resonance mass spectrometer using collision-induced dissociation and photodissociation.

    Science.gov (United States)

    Clemen, Martin; Grotemeyer, Jürgen

    2017-12-01

    The fragmentation behavior of N, N-diethylamino-substituted azobenzene derivatives is investigated by high-resolving mass spectrometry using a Fourier transform ion cyclotron resonance mass spectrometer. Former investigations by photodissociation as well as collision-induced dissociation experiments used to induce a loss of C 3 H 8 from the diethylamino group. The position of the additional proton in [M + H] + ions is important due to the sequences of radical fragmentation reactions. Two possibilities arise. First, a charge is located at the azo group leading to a methyl radical loss. The second possibility is that the charge has been located on the aniline nitrogen of the molecule resulting in an ethyl radical loss. Only o-ethyl red has shown the overall loss of C 3 H 8 in a two-step radical reaction mechanism. Nevertheless, p-ethyl red and ethyl yellow have shown systematic fragmentation reactions as well. Loss of C 3 H 8 has not been likely regarding both these molecules. All experimental findings together with quantum chemical calculations as well as kinetic calculations support the proposed fragmentation mechanisms of the three azo dyes.

  12. Advances in intense beams, beam delivery, targetry, and radiochemistry at advanced cyclotron systems

    Science.gov (United States)

    Johnson, R. R.; Watt, R.; Kovac, B.; Zyuzin, A.; Van Lier, E.; Erdman, K. L.; Gyles, Wm.; Sabaiduc, V.; McQuarrie, S. A.; Wilson, J.; Backhouse, C.; Gelbart, Wm.; Kuo, T.

    2007-08-01

    The increasing demand for radionuclides for PET and SPECT has resulted in ACSI system improvements starting from the cyclotron and proceeding to the Radiochemistry Modules. With more TR30 cyclotrons installed and operating at full capacity, emphasis has been placed on improving the operational components to reduce both the incidence of failure and subsequent maintenance time. A cyclotron system has been developed that meets the needs of a regional radiopharmacy that supplies both positron and single photon emitters that would not otherwise be available. This new system has been named the TR24. In order to deal with some of the challenges of high currents, a method has been developed for passivating the entrance window foil during high current irradiation of a water target used to produce F-18. A method has been developed for passivating the entrance window foil to reduce unwanted chemical species that interfere with radiopharmaceutical production. Preliminary results for novel radioiodine production technique using the TR19/9 are also discussed.

  13. A real-time beam-profile monitor for a PET cyclotron

    Science.gov (United States)

    Hoehr, C.; Uittenbosch, T.; Verzilov, V.; English, W.; Buckley, K.; Gray, D.; Kellog, S.; Cameron, D.; Schaffer, P.

    2012-12-01

    Beam profiles in medical cyclotrons are traditionally measured using techniques that do not provide any information about short-term fluctuations of the beam shape or beam intensity. To overcome this, we have developed a real-time harp beam profile monitor which can withstand beam power in excess of 300 W. The monitor and electronics were constructed and applied toward a 13 MeV proton beam with current of up to 25 μA. Herein are reported preliminary beam-profile measurement results.

  14. Analytical study of effects of positron density and temperature anisotropy on electrostatic ion cyclotron instability

    Science.gov (United States)

    Barati Moqadam Niyat, M.; Khorashadizadeh, S. M.; Niknam, A. R.

    2017-03-01

    The effects of the positron concentration and ion temperature anisotropy on the electrostatic ion cyclotron instability are studied analytically, in a magnetized electron-positron-ion plasma with temperature anisotropy, using the linear kinetic theory. Positrons and electrons are supposed to drift either in the same direction or in opposite directions relative to singly ionized stationary ions and parallel to the magnetic field. The dispersion relation of the electrostatic ion cyclotron waves is derived, and then the conditions for exciting the instability of the waves are investigated. Moreover, the condition for the marginally stable state is also studied. It is found that as the positron concentration and perpendicular ion temperature increase, the growth rate of the electrostatic ion cyclotron instability decreases, whereas the critical drift velocity increases. It is also found that for the chosen set of parameters, with electrons and positrons drifting in the same direction, the instability in the plasma is stronger than when the electrons and positrons drift in opposite directions. In addition, a comparison is made to the normal electron-ion plasma.

  15. Determination of Magnet Specification of 13 MeV Proton Cyclotron Based on Opera 3D

    Directory of Open Access Journals (Sweden)

    Taufik

    2014-08-01

    Full Text Available The magnet is one of the main components of a cyclotron, used to form a circular particle beam trajectories and to provide focusing of the beam. To support the mastery of 13-MeV proton cyclotron technologies, cyclotron magnet design must be done to satisfy cyclotron magnet requirements. This research was conducted by studying important parameters in designing the cyclotron magnet which is then used to determine the design requirements. The magnet design was based on the results of a 3D simulation using Opera 3D software. Opera 3D is a software developed by Cobham plc to solve physical problems in 3D such as magnetostatic using finite element methods. The simulation started by drawing a 3D model of the magnet using a modeler, followed by magnetic field calculations by Tosca module in the Opera 3D software. Simulation results were analyzed with the Genspeo software to determine whether the parameters of the cyclotron magnet have met design requirements. The results indicate that the magnet design satisfied the cyclotron magnet design requirement, that B in the median plane of the magnetic pole approached the isochronous curve, providing axial and radial focusing beam, crossing the resonance line at vr = 1 when the particle energy is low and the particle energy is more than 13 MeV, and lead to small enough phase shift of about 13°. The dimension of the cyclotron magnet is 1.96 m × 1.30 m × 1.21 m; its weight is 17.3 ton; its coil current is 88,024 ampere-turn; its center magnetic field is 1.27479 T; its maximum magnetic field is 1.942116 T; its minimum magnetic field is 0.7689 T; its valley gap is 120 mm; its hill gaps are 40 to 50.78 mm; and its hill angles are 35° to 44°.to 44°

  16. A Tuning Method for Electrically Compensated Ion Cyclotron Resonance Mass Spectrometer Traps

    Science.gov (United States)

    Brustkern, Adam M.; Rempel, Don L.; Gross, Michael L.

    2010-01-01

    We describe a method for tuning electrically compensated ion cyclotron resonance (ICR) traps by tracking the observed cyclotron frequency of an ion cloud at different oscillation mode amplitudes. Although we have used this method to tune the compensation voltages of a custom-built electrically compensated trap, the approach is applicable to other designs that incorporate electrical compensation. To evaluate the effectiveness of tuning, we examined the frequency shift as a function of cyclotron orbit size at different z-mode oscillation amplitudes. The cyclotron frequencies varied by ~ 12 ppm for ions with low z-mode oscillation amplitudes compared to those with high z-mode amplitudes. This frequency difference decreased to ~1 ppm by one iteration of trap tuning. PMID:20060743

  17. Calibration and use cases of the electron cyclotron emission diagnostic at Wendelstein 7-X

    Energy Technology Data Exchange (ETDEWEB)

    Hoefel, Udo; Hirsch, Matthias; Ewert, Karsten; Hartfuss, Hans-Juergen; Laqua, Heinrich Peter; Stange, Torsten; Wolf, Robert [Max-Planck-Institut fuer Plasmaphysik, Greifswald (Germany); Collaboration: the W7-X Team

    2016-07-01

    The world's largest stellarator, Wendelstein 7-X (W7-X), is equipped with a 140 GHz electron cyclotron resonance heating (ECRH) system providing up to 5 MW absorbed power in the first operation phase OP1.1. The foreseen X2-heating scenario uses the high absorption of the second harmonic extraordinary electron cyclotron waves, which leads on the other hand to a black body electron cyclotron emission (ECE) being proportional to the local electron temperature. ECE is one of the fundamental operating diagnostics and is planned to yield the electron temperature profile from the very first discharges onwards. Unlike most other ECE diagnostics, the 32 channel ECE radiometer diagnostic (with additional 16 channels with higher radial resolution) at W7-X is absolutely calibrated. It is planned to use this diagnostic for intensive studies on electron heat transport in the upcoming operational phases of W7-X. Simple switch-off experiments for the determination of the energy confinement time should already be possible within the first plasma shots. Due to the high temporal and radial resolution the ECE will be used also to determine the power deposition by modulation of the heating gyrotron. or the localization of a power modulated ECRH to optimize the power deposition. If reasonably equilibrated plasma conditions could be generated in the first operational phase (OP 1.1), first studies on electron thermal diffusivity could also be possible.

  18. A stem batrachian from the Early Permian of Texas and the origin of frogs and salamanders.

    Science.gov (United States)

    Anderson, Jason S; Reisz, Robert R; Scott, Diane; Fröbisch, Nadia B; Sumida, Stuart S

    2008-05-22

    The origin of extant amphibians (Lissamphibia: frogs, salamanders and caecilians) is one of the most controversial questions in vertebrate evolution, owing to large morphological and temporal gaps in the fossil record. Current discussions focus on three competing hypotheses: a monophyletic origin within either Temnospondyli or Lepospondyli, or a polyphyletic origin with frogs and salamanders arising among temnospondyls and caecilians among the lepospondyls. Recent molecular analyses are also controversial, with estimations for the batrachian (frog-salamander) divergence significantly older than the palaeontological evidence supports. Here we report the discovery of an amphibamid temnospondyl from the Early Permian of Texas that bridges the gap between other Palaeozoic amphibians and the earliest known salientians and caudatans from the Mesozoic. The presence of a mosaic of salientian and caudatan characters in this small fossil makes it a key taxon close to the batrachian (frog and salamander) divergence. Phylogenetic analysis suggests that the batrachian divergence occurred in the Middle Permian, rather than the late Carboniferous as recently estimated using molecular clocks, but the divergence with caecilians corresponds to the deep split between temnospondyls and lepospondyls, which is congruent with the molecular estimates.

  19. Unsustainable Home Telehealth: A Texas Qualitative Study.

    Science.gov (United States)

    Radhakrishnan, Kavita; Xie, Bo; Jacelon, Cynthia S

    2016-10-01

    Telehealth has emerged as an innovative approach to aid older individuals in managing chronic diseases in their homes and avoid hospitalizations and institutionalization. However, the sustainability of home telehealth programs remains a major challenge. This qualitative study explored the reasons for the initial adoption and the eventual decline of a decade-long home telehealth program at a Texas home health agency (HHA). Barriers to and facilitators for sustaining home telehealth programs were also explored. Semistructured interviews of 13 HHA nursing staff and administrators, 1 physician, and 9 patients aged >55 years and their informal caregivers who used telehealth were conducted in summer 2013. Interview transcripts were analyzed using conventional content analysis. Data analysis generated 5 themes representing the decline of the Texas home telehealth program: its impact on patient-centered outcomes, its cost-effectiveness, patient-clinician and interprofessional communication, technology usability, and home health management culture. Lack of significant impact on patient outcomes, in addition to financial, technical, management, and communication-related challenges, adversely affected the sustainability of this home telehealth program. A home telehealth program that attains patient-centered outcomes, improves cost-effectiveness of managing chronic diseases, improves quality of communication among patients and clinicians, is user-friendly for older adults, and involves end users in decision making is likely to be sustainable. © The Author 2015. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  20. Resource Management in a Changing Climate: Understanding the Relationships between Water Quality and Golden Alga Distribution in the Pecos River, New Mexico and Texas

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Texas Tech University will conduct sampling at a wide variety of sites in the Middle and Lower Pecos River for golden alga and environmental variables. The toxins...

  1. Optically detected cyclotron resonance in a single GaAs/AlGaAs heterojunction

    Energy Technology Data Exchange (ETDEWEB)

    Bartsch, Gregor

    2011-09-23

    Optically detected far-infrared cyclotron resonance (FIR-ODCR) in GaAs/AlGaAs HJs is interpreted in the frame of an exciton-dissociation mechanism. It is possible to explain the ODR mechanism by an exciton drag, mediated by ballistically propagating phonons. Furthermore, very narrow resonances are presented and realistic electron mobility values can be calculated. The exceptionally narrow ODCRs allow to measure conduction-band nonparabolicity effects and resolve satellite resonances, close to the main cyclotron resonance line.

  2. Chemical and physical characteristics of water in estuaries of Texas; October 1978-September 1983

    Science.gov (United States)

    Fisher, J.C.; Grozier, R.U.

    1985-01-01

    The Texas Water Plan (Texas Water Development Board, 1968) proposed development and utilization of water resources in Texas and included a provision for the use and preservation of water in the estuaries of the State. Management of estuarine waters requires knowledge of the hydrodynamics and of the continuing changes in the chemical and physical characteristics of water in the estuaries.

  3. Multicavity proton cyclotron accelerator

    Directory of Open Access Journals (Sweden)

    J. L. Hirshfield

    2002-08-01

    Full Text Available A mechanism for acceleration of protons is described, in which energy gain occurs near cyclotron resonance as protons drift through a sequence of rotating-mode TE_{111} cylindrical cavities in a strong nearly uniform axial magnetic field. Cavity resonance frequencies decrease in sequence from one another with a fixed frequency interval Δf between cavities, so that synchronism can be maintained between the rf fields and proton bunches injected at intervals of 1/Δf. An example is presented in which a 122 mA, 1 MeV proton beam is accelerated to 961 MeV using a cascade of eight cavities in an 8.1 T magnetic field, with the first cavity resonant at 120 MHz and with Δf=8 MHz. Average acceleration gradient exceeds 40 MV/m, average effective shunt impedance is 223 MΩ/m, but maximum surface field in the cavities does not exceed 7.2 MV/m. These features occur because protons make many orbital turns in each cavity and thus experience acceleration from each cavity field many times. Longitudinal and transverse stability appear to be intrinsic properties of the acceleration mechanism, and an example to illustrate this is presented. This acceleration concept could be developed into a proton accelerator for a high-power neutron spallation source, such as that required for transmutation of nuclear waste or driving a subcritical fission burner, provided a number of significant practical issues can be addressed.

  4. Measuring canopy loss and climatic thresholds from an extreme drought along a fivefold precipitation gradient across Texas.

    Science.gov (United States)

    Schwantes, Amanda M; Swenson, Jennifer J; González-Roglich, Mariano; Johnson, Daniel M; Domec, Jean-Christophe; Jackson, Robert B

    2017-12-01

    Globally, trees are increasingly dying from extreme drought, a trend that is expected to increase with climate change. Loss of trees has significant ecological, biophysical, and biogeochemical consequences. In 2011, a record drought caused widespread tree mortality in Texas. Using remotely sensed imagery, we quantified canopy loss during and after the drought across the state at 30-m spatial resolution, from the eastern pine/hardwood forests to the western shrublands, a region that includes the boundaries of many species ranges. Canopy loss observations in ~200 multitemporal fine-scale orthophotos (1-m) were used to train coarser Landsat imagery (30-m) to create 30-m binary statewide canopy loss maps. We found that canopy loss occurred across all major ecoregions of Texas, with an average loss of 9.5%. The drought had the highest impact in post oak woodlands, pinyon-juniper shrublands and Ashe juniper woodlands. Focusing on a 100-km by ~1,000-km transect spanning the State's fivefold east-west precipitation gradient (~1,500 to ~300 mm), we compared spatially explicit 2011 climatic anomalies to our canopy loss maps. Much of the canopy loss occurred in areas that passed specific climatic thresholds: warm season anomalies in mean temperature (+1.6°C) and vapor pressure deficit (VPD, +0.66 kPa), annual percent deviation in precipitation (-38%), and 2011 difference between precipitation and potential evapotranspiration (-1,206 mm). Although similarly low precipitation occurred during the landmark 1950s drought, the VPD and temperature anomalies observed in 2011 were even greater. Furthermore, future climate data under the representative concentration pathway 8.5 trajectory project that average values will surpass the 2011 VPD anomaly during the 2070-2099 period and the temperature anomaly during the 2040-2099 period. Identifying vulnerable ecological systems to drought stress and climate thresholds associated with canopy loss will aid in predicting how forests will

  5. A comparative study of historical droughts over Texas, USA and Murray-Darling Basin, Australia: Factors influencing initialization and cessation

    Science.gov (United States)

    Verdon-Kidd, Danielle C.; Scanlon, Bridget R.; Ren, Tong; Fernando, D. Nelun

    2017-02-01

    Water availability and food security are tightly coupled on a global scale. The occurrence of drought puts this balance at risk due to reductions in dryland farming production and water allocations to irrigated agriculture. Improved understanding of drought initiation and cessation would therefore be beneficial for drought planning and management. The study objective was to determine factors affecting drought initiation and cessation over the past century in two climatologically similar regions that represent net agricultural exporters; south central U.S. (Texas) and southeast Australia (Murray Darling Basin, MDB). Drought indices included the Standardized Precipitation Index (SPI, 1900-2014) for meteorological drought, the Normalized Difference Vegetation Index (NDVI, 1981-2014) for agricultural drought, and the Streamflow Drought Index (SDI, 1930-2014) for hydrological drought. Results show that meteorological drought tends to develop gradually over a period of up to six months, with agricultural drought developing shortly thereafter (within one month) in both regions. Evidence of hydrological drought was observed within one month (Texas) and within four months (MDB) on average after meteorological drought was established. Further, droughts appear to cease more quickly than they initiate over Texas, whereas rates of drought initiation and cessation are similar over the MDB. Drought breaking rainfall in Texas is generally a result of a southward shift in the Polar Jet Stream or a low-pressure trough over central North America, whereas drought cessation in the MDB is typically associated with a monsoon trough or low-pressure system in the Tasman Sea/Great Australian Bight. Improved knowledge of the climate mechanisms controlling the onset and termination of drought periods should enhance drought forecasts and improve drought management practices, particularly in regions where water security is a primary objective.

  6. 68Ga-PET: a powerful generator-based alternative to cyclotron-based PET radiopharmaceuticals.

    Science.gov (United States)

    Fani, Melpomeni; André, João P; Maecke, Helmut R

    2008-01-01

    PET (positron emission tomography) is a powerful diagnostic and imaging technique which requires short-lived positron emitting isotopes. The most commonly used are accelerator-produced (11)C and (18)F. An alternative is the use of metallic positron emitters. Among them (68)Ga deserves special attention because of its availability from long-lived (68)Ge/(68)Ga generator systems which render (68)Ga radiopharmacy independent of an onsite cyclotron. The coordination chemistry of Ga(3+) is dominated by its hard acid character. A variety of mono- and bifunctional chelators have been developed which allow the formation of stable (68)Ga(3+)complexes and convenient coupling to biomolecules. (68)Ga coupling to small biomolecules is potentially an alternative to (18)F- and (11)C-based radiopharmacy. In particular, peptides targeting G-protein coupled receptors overexpressed on human tumour cells have shown preclinically and clinically high and specific tumour uptake. Kit-formulated precursors along with the generator may be provided, similar to the (99)Mo/(99m)Tc-based radiopharmacy, still the mainstay of nuclear medicine.

  7. Advanced electron cyclotron heating and current drive experiments on the stellarator Wendelstein 7-X

    Directory of Open Access Journals (Sweden)

    Stange Torsten

    2017-01-01

    Full Text Available During the first operational phase (OP 1.1 of Wendelstein 7-X (W7-X electron cyclotron resonance heating (ECRH was the exclusive heating method and provided plasma start-up, wall conditioning, heating and current drive. Six gyrotrons were commissioned for OP1.1 and used in parallel for plasma operation with a power of up to 4.3 MW. During standard X2-heating the spatially localized power deposition with high power density allowed controlling the radial profiles of the electron temperature and the rotational transform. Even though W7-X was not fully equipped with first wall tiles and operated with a graphite limiter instead of a divertor, electron densities of n e > 3·1019 m-3 could be achieved at electron temperatures of several keV and ion temperatures above 2 keV. These plasma parameters allowed the first demonstration of a multipath O2-heating scenario, which is envisaged for safe operation near the X-cutoff-density of 1.2·1020 m-3 after full commissioning of the ECRH system in the next operation phase OP1.2.

  8. Advanced electron cyclotron heating and current drive experiments on the stellarator Wendelstein 7-X

    Science.gov (United States)

    Stange, Torsten; Laqua, Heinrich Peter; Beurskens, Marc; Bosch, Hans-Stephan; Bozhenkov, Sergey; Brakel, Rudolf; Braune, Harald; Brunner, Kai Jakob; Cappa, Alvaro; Dinklage, Andreas; Erckmann, Volker; Fuchert, Golo; Gantenbein, Gerd; Gellert, Florian; Grulke, Olaf; Hartmann, Dirk; Hirsch, Matthias; Höfel, Udo; Kasparek, Walter; Knauer, Jens; Langenberg, Andreas; Marsen, Stefan; Marushchenko, Nikolai; Moseev, Dmitry; Pablant, Novomir; Pasch, Ekkehard; Rahbarnia, Kian; Mora, Humberto Trimino; Tsujimura, Toru; Turkin, Yuriy; Wauters, Tom; Wolf, Robert

    2017-10-01

    During the first operational phase (OP 1.1) of Wendelstein 7-X (W7-X) electron cyclotron resonance heating (ECRH) was the exclusive heating method and provided plasma start-up, wall conditioning, heating and current drive. Six gyrotrons were commissioned for OP1.1 and used in parallel for plasma operation with a power of up to 4.3 MW. During standard X2-heating the spatially localized power deposition with high power density allowed controlling the radial profiles of the electron temperature and the rotational transform. Even though W7-X was not fully equipped with first wall tiles and operated with a graphite limiter instead of a divertor, electron densities of n e > 3·1019 m-3 could be achieved at electron temperatures of several keV and ion temperatures above 2 keV. These plasma parameters allowed the first demonstration of a multipath O2-heating scenario, which is envisaged for safe operation near the X-cutoff-density of 1.2·1020 m-3 after full commissioning of the ECRH system in the next operation phase OP1.2.

  9. ELECTRON CYCLOTRON WAVES

    NARCIS (Netherlands)

    Westerhof, E.

    2010-01-01

    This lecture gives an overview of heating and current drive with electron cyclotron waves. We present the main theoretical aspects of wave propagation, wave absorption, and non-inductive current drive, as well as important technical aspects for the application of high power electron cyclotron waves,

  10. Electron cyclotron waves

    NARCIS (Netherlands)

    Westerhof, E.

    2012-01-01

    This lecture gives an overview of heating and current drive with electron cyclotron waves. We present the main theoretical aspects of wave propagation, wave absorption, and non-inductive current drive, as well as important technical aspects for the application of high power electron cyclotron waves,

  11. Electron cyclotron waves

    NARCIS (Netherlands)

    Westerhof, E.

    2008-01-01

    This lecture gives an overview of heating and current drive with electron cyclotron waves. We present the main theoretical aspects of wave propagation, wave absorption, and non-inductive current drive, as well as important technical aspects for the application of high power electron cyclotron waves,

  12. Ready, Willing, and Unable: How Financial Barriers Obstruct Bachelor-Degree Attainment in Texas. A Report to the 80th Regular Session of the Texas Legislature. December 2006-Revised

    Science.gov (United States)

    Webster, Jeff; Creusere, Marlena; McQueen, Carla; Goode, Meredith; Barone, Sandra; Wang, David

    2006-01-01

    The United States is losing high-paying jobs to countries that produce a more reliable supply of college graduates in math and science. Texas faces its own economic slowdown if it is unable to graduate more students with bachelor's degrees. The state has been addressing many of the obstacles students face in earning a four-year degree. Outreach…

  13. A historical perspective on precipitation, drought severity, and streamflow in Texas during 1951-56 and 2011

    Science.gov (United States)

    Winters, Karl E.

    2013-01-01

    The intense drought throughout Texas during 2011 resulted in substantial declines in streamflow. By April 2011, nearly all of the State was experiencing severe to extreme drought according to data from the University of Nebraska–Lincoln Drought Monitor. By the end of July 2011, more than 75 percent of the State was experiencing exceptional drought. The worst of the drought occurred around October 4, 2011, when 97 percent of Texas was suffering from extreme to exceptional drought. The historical drought of 1951–56 has long been used by water-resource managers, engineers, and scientists as a point of reference for water-supply planning. A comparison of drought conditions during the 2011 water year (October 1, 2010, through September 30, 2011) to the historical drought of 1951–56 from a hydrologic perspective serves as an additional reference for water-supply planning.

  14. Neigiamojo standumo vibroizoliacinio staliuko „MINUS K 500BM-1“ tyrimas

    Directory of Open Access Journals (Sweden)

    Vitalija Meškelytė

    2012-01-01

    Full Text Available Nagrinėjamas neigiamojo standumo (angl. negative-stiffness vibroizoliacinio staliuko „Minus K 500BM-1“ efektyvumas 2–110 Hz diapazone. Apžvelgti kiti galimi vibroizoliacijos būdai. Atlikti eksperimentiniai vibracijų perduodamumo tyrimai. Išbandyta speciali vibracijų žadinimo įranga, leidžianti atlikti numatytus bandomojo objekto tyrimus. Aprašyta eksperimentinių tyrimų metodika. Pateikti eksperimentų metu gauti rezultatai ir išvados.

  15. Gambling in Texas: 1995 Surveys of Adult and Adolescent Gambling Behavior.

    Science.gov (United States)

    Wallisch, Lynn S.

    The impact of the Texas State Lottery on gambling patterns, expenditures on gambling, and the prevalence of problem gambling in Texas is assessed. Background and methodology is presented in Part 1. Data are compared with a survey run prior to the introduction of the first state lottery. Part 2, "Gambling among Texas Adults," includes…

  16. Integrated Plasma Simulation of Ion Cyclotron and Lower Hybrid Range of Frequencies Actuators in Tokamaks

    Science.gov (United States)

    Bonoli, P. T.; Shiraiwa, S.; Wright, J. C.; Harvey, R. W.; Batchelor, D. B.; Berry, L. A.; Chen, Jin; Poli, F.; Kessel, C. E.; Jardin, S. C.

    2012-10-01

    Recent upgrades to the ion cyclotron RF (ICRF) and lower hybrid RF (LHRF) components of the Integrated Plasma Simulator [1] have made it possible to simulate LH current drive in the presence of ICRF minority heating and mode conversion electron heating. The background plasma is evolved in these simulations using the TSC transport code [2]. The driven LH current density profiles are computed using advanced ray tracing (GENRAY) and Fokker Planck (CQL3D) [3] components and predictions from GENRAY/CQL3D are compared with a ``reduced'' model for LHCD (the LSC [4] code). The ICRF TORIC solver is used for minority heating with a simplified (bi-Maxwellian) model for the non-thermal ion tail. Simulation results will be presented for LHCD in the presence of ICRF heating in Alcator C-Mod. [4pt] [1] D. Batchelor et al, Journal of Physics: Conf. Series 125, 012039 (2008).[0pt] [2] S. C. Jardin et al, J. Comp. Phys. 66, 481 (1986).[0pt] [3] R. W. Harvey and M. G. McCoy, Proc. of the IAEA Tech. Comm. Meeting on Simulation and Modeling of Therm. Plasmas, Montreal, Canada (1992).[0pt] [4] D. Ignat et al, Nucl. Fus. 34, 837 (1994).[0pt] [5] M. Brambilla, Plasma Phys. and Cont. Fusion 41,1 (1999).

  17. Diagnostic assessment to estimate and minimize neutron dose rates received by occupationally exposed individuals at cyclotron facilities.

    Science.gov (United States)

    Reina, L C; Silva, A X; Suita, J C; Souza, M I S; Facure, A; Silva, J C P; Furlanetto, J A D; Rebello, W

    2010-03-01

    Since 2003, radiopharmaceuticals for medical diagnostic purposes have been produced at the Instituto de Engenharia Nuclear, in Brazil, using two cyclotron accelerators - CV-28 and RDS111. As a result of the ever increasing production, a diagnostic assessment to reduce neutron dose rates received by occupationally exposed individuals during irradiation processes has been developed. The purpose of this work is to present this assessment, which is currently being applied to both the Fluorine and Iodine targets of CV-28 and RDS111 cyclotron accelerators. Copyright 2009 Elsevier Ltd. All rights reserved.

  18. Creating a disease risk map for West Nile virus for surveillance in Central Texas using a Geographic Information System and Remote Sensing technologies

    Science.gov (United States)

    Following the discovery of the West Nile virus (WNv) in Brazos County, TX in 2002, mosquito research personnel at Texas A&M University established a routine WNv mosquito vector surveillance program in the county. In 2004, a map of Brazos County was created depicting areas that had a heightened leve...

  19. Molecular evidence of heavy-oil weathering following the M/V Cosco Busan spill: insights from Fourier transform ion cyclotron resonance mass spectrometry.

    Science.gov (United States)

    Lemkau, Karin L; McKenna, Amy M; Podgorski, David C; Rodgers, Ryan P; Reddy, Christopher M

    2014-04-01

    Recent studies have highlighted a critical need to investigate oil weathering beyond the analytical window afforded by conventional gas chromatography (GC). In particular, techniques capable of detecting polar and higher molecular weight (HMW; > 400 Da) components abundant in crude and heavy fuel oils (HFOs) as well as transformation products. Here, we used atmospheric pressure photoionization Fourier transform ion cyclotron resonance mass spectrometry (APPI FT-ICR MS) to identify molecular transformations in oil-residue samples from the 2007 M/V Cosco Busan HFO spill (San Francisco, CA). Over 617 days, the abundance and diversity of oxygen-containing compounds increased relative to the parent HFO, likely from bio- and photodegradation. HMW, highly aromatic, alkylated compounds decreased in relative abundance concurrent with increased relative abundance of less alkylated stable aromatic structures. Combining these results with GC-based data yielded a more comprehensive understanding of oil spill weathering. For example, dealkylation trends and the overall loss of HMW species observed by FT-ICR MS has not previously been documented and is counterintuitive given losses of lower molecular weight species observed by GC. These results suggest a region of relative stability at the interface of these techniques, which provides new indicators for studying long-term weathering and identifying sources.

  20. A Progress Report on the TeXas Earth and Space Science (TXESS) Revolution

    Science.gov (United States)

    Ellins, K. K.; Snow, E.; Olson, H. C.; Odell, M. R.; Stocks, E.

    2009-12-01

    The TeXas Earth and Space Science (TXESS) Revolution is a five-year, NSF-sponsored professional development program for minority-serving 8th grade and high science school teachers who are preparing to teach a new senior capstone course in Earth and Space Science that is an option for the four years of science required for high school graduation in Texas. In this presentation (1) we will describe the sequence and content of the professional development academies and the summer institutes; (2) report on our effort to reach minority students; (3) review the preliminary results of the project evaluation on the effectiveness of the TXESS Revolution professional development program; and (4) describe enrichment opportunities for TXESS Revolution participants in connection with other projects, professional organizations and consortia (e.g., UNAVCO, IRIS, and the Consortium for Ocean Leadership). The program consists of eight professional development academies, each with a different contemporary content theme, during which teachers engage in rigorous, data-driven learning activities. Field trips, guest lectures, and other special programs are integrated into the professional development. Summer institutes are offered each year. The number of teachers participating in Cohorts A (spring 2008- summer 2009), B (fall 2008 - summer 2010) and C (fall 2009 - summer 2011) is 160. Cohort A and B teachers have directly impacted 9,494 K-12 students of which 67% are Hispanic, African American, Asian American or Native American, and 35% are Caucasian. Thirty-five Cohort A teachers have turned the training around and offered project-related professional development to 1,356 other teachers. The content of the TXESS Revolution worklshops is rigorous. Evaluation results reveal that many teachers felt overwhelmed at the start of the project. However, they soon became accustomed to the level of information presented and felt increased confidence in the core content. Participants appreciate how

  1. Using the Orbit Tracking Code Z3CYCLONE to Predict the Beam Produced by a Cold Cathode PIG Ion Source for Cyclotrons under DC Extraction

    CERN Document Server

    Forringer, Edward

    2005-01-01

    Experimental measurements of the emittance and luminosity of beams produced by a cold-cathode Phillips Ionization Guage (PIG) ion source for cyclotrons under dc extraction are reviewed. (The source being studied is of the same style as ones that will be used in a series of 250 MeV proton cyclotrons being constructed for cancer therapy by ACCEL Inst, Gmbh, of Bergisch Gladbach, Germany.) The concepts of 'plasma boundary' and 'plasma temperature' are presented as a useful set of parameters for describing the initial conditions used in computational orbit tracking. Experimental results for r-pr and z-pz emittance are compared to predictions from the MSU orbit tracking code Z3CYCLONE with results indicating that the code is able to predict the beam produced by these ion sources with adequate accuracy such that construction of actual cyclotrons can proceed with reasonably prudent confidence that the cyclotron will perform as predicted.

  2. Enhancement of beam pulse controllability for a single-pulse formation system of a cyclotron.

    Science.gov (United States)

    Kurashima, Satoshi; Miyawaki, Nobumasa; Kashiwagi, Hirotsugu; Okumura, Susumu; Taguchi, Mitsumasa; Fukuda, Mitsuhiro

    2015-07-01

    The single-pulse formation technique using a beam chopping system consisting of two types of high-voltage beam kickers was improved to enhance the quality and intensity of the single-pulse beam with a pulse interval over 1 μs at the Japan Atomic Energy Agency cyclotron facility. A contamination rate of neighboring beam bunches in the single-pulse beam was reduced to less than 0.1%. Long-term purification of the single pulse beam was guaranteed by the well-controlled magnetic field stabilization system for the cyclotron magnet. Reduction of the multi-turn extraction number for suppressing the neighboring beam bunch contamination was achieved by restriction of a beam phase width and precise optimization of a particle acceleration phase. In addition, the single-pulse beam intensity was increased by a factor of two or more by a combination of two types of beam bunchers using sinusoidal and saw-tooth voltage waveforms. Provision of the high quality intense single-pulse beam contributed to improve the accuracy of experiments for investigation of scintillation light time-profile and for neutron energy measurement by a time-of-flight method.

  3. Development of a prototype T-shaped fast switching device for electron cyclotron current drive systems

    Science.gov (United States)

    Sekiguchi, Kenji; Nagashima, Koji; Honzu, Toshihiko; Saigusa, Mikio; Oda, Yasuhisa; Takahashi, Koji; Sakamoto, Keishi

    2016-09-01

    A T-shaped high-power switching device composed of circular corrugated waveguides with three ports and double dielectric disks made of sapphire was proposed as a fast switching device based on a new principle in electron cyclotron current drive systems. This switching device has the advantages of operating at a fixed frequency and being compact. The design of the prototype switch was obtained by numerical simulations using a finite-difference time-domain (FDTD) method. The size of these components was optimized for the frequency band of 170 GHz. Low-power tests were carried out in a cross-shaped model.

  4. An intrinsically safe facility for forefront research and training on nuclear technologies — An example of accelerator: the SPES cyclotron

    Science.gov (United States)

    Maggiore, M.; Lombardi, A.; Piazza, L. A. C.; Prete, G.

    2014-04-01

    The SPES project, under construction at INFN, Laboratori Nazionali di Legnaro, is a research facility for nuclear and applied physics, based on a high-current H- cyclotron with two exits. One exit will be devoted to supply an ISOL facility for the production of radioactive beams, the second one can be used as driver for the ADS system. The main characteristics of the cyclotron are described together with the main building designed to operate high-current proton beams according to radioprotection rules.

  5. Synthesis of model humic substances: a mechanistic study using controllable H/D exchange and Fourier transform ion cyclotron resonance mass spectrometry.

    Science.gov (United States)

    Zherebker, Alexander Ya; Airapetyan, David; Konstantinov, Andrey I; Kostyukevich, Yury I; Kononikhin, Alexey S; Popov, Igor A; Zaitsev, Kirill V; Nikolaev, Eugene N; Perminova, Irina V

    2015-07-07

    The products of the oxidative coupling of phenols are frequently used as synthetic analogues to natural humic substances (HS) for biomedical research. However, their molecular compositions and exact structures remain largely unknown. The objective of this study was to develop a novel approach for the molecular-level analysis of phenolic polymerisates that is capable of inventorying molecular constituents and resolving their distinct structural formulas. For this purpose, we have synthesized the model HS using the oxidative coupling of a specifically designed phenylpropanoic monomer, 3-(4-hydroxy-3-methoxyphenyl)-3-oxopropionic acid, to hydroquinone. We have characterized the synthesized model HS using high resolution Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS), (1)H NMR spectroscopy, and controllable hydrogen/deuterium (H/D) exchange. We succeeded in the molecular inventory of the model HS. The assigned molecular formulas occupied the substantial space of CHO compositions in the Van Krevelen diagram with a maximum density found in the regions of tannins and lignins, resembling those of natural HS. To identify the exact structural formulas of the individual constituents in the model HS, we have applied selective H/D exchange of non-labile backbone protons by a choice of basic or acidic catalytic conditions followed by FTICR MS. The determined formulas allowed us to verify the proposed pathways of hydroxylation and carboxylation in the course of the phenolic coupling and to identify the acetylation of aromatic rings as an important side reaction. We conclude that the proposed analytical approach may be used to identify the molecular carriers of biological activity within the phenolic polymerisates and eventually within natural HS.

  6. Patterns of precipitation and soil moisture extremes in Texas, US: A complex network analysis

    Science.gov (United States)

    Sun, Alexander Y.; Xia, Youlong; Caldwell, Todd G.; Hao, Zengchao

    2018-02-01

    Understanding of the spatial and temporal dynamics of extreme precipitation not only improves prediction skills, but also helps to prioritize hazard mitigation efforts. This study seeks to enhance the understanding of spatiotemporal covariation patterns embedded in precipitation (P) and soil moisture (SM) by using an event-based, complex-network-theoretic approach. Events concurrences are quantified using a nonparametric event synchronization measure, and spatial patterns of hydroclimate variables are analyzed by using several network measures and a community detection algorithm. SM-P coupling is examined using a directional event coincidence analysis measure that takes the order of event occurrences into account. The complex network approach is demonstrated for Texas, US, a region possessing a rich set of hydroclimate features and is frequented by catastrophic flooding. Gridded daily observed P data and simulated SM data are used to create complex networks of P and SM extremes. The uncovered high degree centrality regions and community structures are qualitatively in agreement with the overall existing knowledge of hydroclimate extremes in the study region. Our analyses provide new visual insights on the propagation, connectivity, and synchronicity of P extremes, as well as the SM-P coupling, in this flood-prone region, and can be readily used as a basis for event-driven predictive analytics for other regions.

  7. Characterization and Field Studies of a Cucumber Mosaic Virus Isolate from Spinach in the Winter Garden Area of Texas

    Science.gov (United States)

    A. Dan Wilson; R.S. Halliwell

    1985-01-01

    An isolate of cucumber mosaic virus (CMV) was identified from spinach in the Winter Garden area of Texas. The isolate was very closely related serologically to strain S of CMVand is designated the Texas spinach isolate of CMV-S. The virus infected 39 species of crop plants and wild hosts in 12 of 13 families tested. The green peach aphid efficiently transmitted the...

  8. Cyclotrons: From Science to Human Health

    Science.gov (United States)

    Craddock, Michael

    2011-04-01

    Lawrence's invention of the cyclotron, whose 80th anniversary we have just celebrated, not only revolutionized nuclear physics, but proved the starting point for a whole variety of recirculating accelerators, from the smallest microtron to the largest synchrotron, that have had an enormous impact in almost every branch of science and in several areas of medicine and industry. Cyclotrons themselves have proved remarkably adaptable, incorporating a variety of new ideas and technologies over the years: frequency modulation, edge focusing, AG focusing, separate magnet sectors, axial and azimuthal injection, ring geometries, stripping extraction, superconducting magnets and rf...... Even FFAGs, those most complex members of the cyclotron (fixed-magnetic-field) family, are making a comeback. Currently there are more than 50 medium or large cyclotrons around the world devoted to research. These provide intense primary beams of protons or stable ions, and correspondingly intense secondary beams of neutrons, pions, muons and radioactive ions, for experiments in nuclear, particle and condensed-matter physics, and in the materials and life sciences. Far outnumbering these, however, are the 800 or so small and medium cyclotrons used to produce radioisotopes for medical and other purposes. In addition, a rapidly growing number of 230-MeV proton cyclotrons are being built for cancer therapy -12 brought into operation since 1998 and as many more in the works. Altogether, cyclotrons are flourishing!

  9. Plasma response measurements of external magnetic perturbations using electron cyclotron emission and comparisons to 3D ideal MHD equilibrium

    CERN Document Server

    Willensdorfer, M; Strumberger, E; Suttrop, W; Vanovac, B; Brida, D; Cavedon, M; Classen, I; Dunne, M; Fietz, S; Fischer, R; Kirk, A; Laggner, F M; Liu, Y Q; Odstrcil, T; Ryan, D A; Viezzer, E; Zohm, H; Luhmann, I C

    2016-01-01

    The plasma response from an external n = 2 magnetic perturbation field in ASDEX Upgrade has been measured using mainly electron cyclotron emission (ECE) diagnostics and a rigid rotating field. To interpret ECE and ECE-imaging (ECE-I) measurements accurately, forward modeling of the radiation transport has been combined with ray tracing. The measured data is compared to synthetic ECE data generated from a 3D ideal magnetohydrodynamics (MHD) equilibrium calculated by VMEC. The measured amplitudes of the helical displacement in the midplane are in reasonable agreement with the one from the synthetic VMEC diagnostics. Both exceed the vacuum field calculations and indicate the presence of an amplified kink response at the edge. Although the calculated magnetic structure of this edge kink peaks at poloidal mode numbers larger than the resonant components |m| > |nq|, the displacement measured by ECE-I is almost resonant |m| ~ |nq|. This is expected from ideal MHD in the proximity of rational surfaces. VMEC and MARS-...

  10. Accessing Disadvantaged Pregnant Women in Houston, Texas, and Characterizing Biomarkers of Metal Exposure: A Feasibility Study

    Directory of Open Access Journals (Sweden)

    Kristina W. Whitworth

    2017-04-01

    Full Text Available Abstract: Communities of color or low socioeconomic status are disproportionately affected by metal exposure given spatial variability of the ambient levels of these contaminants. Despite this, there is little research characterizing metal concentrations in blood among disadvantaged populations in the U.S., especially among pregnant women who are particularly vulnerable and difficult to access. Thus, we conducted a pilot study among disadvantaged pregnant women in Houston, Texas to assess willingness to participate in key activities of an epidemiologic study and characterize exposures to 16 metals. Thirty-one women attending a Medicaid-serving prenatal clinic were included in this pilot study and completed an interviewer-administered questionnaire. We obtained and measured metal compounds in whole blood samples for 22 of these women during third-trimester prenatal visits. Median whole blood concentrations of Ni, As, Cd, and Pb were 27, 1.4, 0.6, and 6.3 µg/L, respectively. Most women were willing to participate in critical aspects of a research study, including wearing a personal air-sampling badge for 2–3 days (87.1%, receiving ultrasounds (83.9%, and providing blood draws (64.5%. Despite the small sample, our results provide evidence of women’s metal exposure and their willingness to participate in future research studies to elucidate exposure pathways and explore related health effects experienced among this population of disadvantaged pregnant women.

  11. Theory of electromagnetic cyclotron wave growth in a time-varying magnetoplasma

    Science.gov (United States)

    Gail, William B.

    1990-01-01

    The effect of a time-dependent perturbation in the magnetoplasma on the wave and particle populations is investigated using the Kennel-Petchek (1966) approach. Perturbations in the cold plasma density, energetic particle distribution, and resonance condition are calculated on the basis of the ideal MHD assumption given an arbitrary compressional magnetic field perturbation. An equation is derived describing the time-dependent growth rate for parallel propagating electromagnetic cyclotron waves in a time-varying magnetoplasma with perturbations superimposed on an equilibrium configuration.

  12. Soil Black Carbon Loss and Sediment Black Carbon Accumulation in a Central Texas Woodland

    Science.gov (United States)

    Schieve, E. A.; Hockaday, W. C.; White, J. D.

    2016-12-01

    The Balcones Canyonlands National Wildlife Refuge is located along the eastern edge of the Edwards Plateau in Texas, and was established in 1992 for the purpose of conserving habitat for two endangered bird species. The landscape is composed of hilly, mesa-valley terrain, which is mostly covered by grasslands and woodlands dominated by juniper with intermingling of various oak species. Based on historical photo analysis and tree fire scar dendrochronology, the area has experienced major land use changes over the last century due to wildfire, logging, and drought affecting soil stability and woodland species composition. A previous study on soil black carbon showed that site-specific soil erosion potential and time since last fire may act as controls on soil black carbon concentrations. However, the black carbon transport flux, depositional fate, or the magnitude of soil erosion effects upon the black carbon budget are unconstrained at the watershed scale. To address this, we sampled the sediments accumulating in small ponds constructed during the 1950's for livestock watering. We are quantifying black carbon in sediments using solid-state 13C nuclear magnetic resonance spectroscopy. Preliminary data suggest that the pond sediments are a black carbon sink. Black carbon comprises 15 % - 25 %, of the sedimentary organic carbon, as substantial enrichment relative to soils within the watershed. We will present an early assessment of the black carbon erosion and sediment accumulation rates in first- and second-order watersheds.

  13. Cyclotron Radiation Emission Spectroscopy: First demonstration and performance benchmarks from the Project 8 experiment

    Science.gov (United States)

    LaRoque, Benjamin Hines

    The Project 8 collaboration is taking a phased approach to developing an experimental search for the absolute neutrino mass scale, based on a novel technique, Cyclotron Radiation Emission Spectroscopy. The first phase was a demonstration of this new spectroscopy technique using a well understood source of narrow conversion electron lines, 83mKr, as a proof of principle. Results from the first successful operation of the detector are presented, demonstrating the viability of the approach. The strong conversion electron lines near 17.8, 30.4, and 32 keV were observed with full width at half maximum between 140 eV and 15 eV depending on the choice of trapping configuration used. Various upgrades were made to the detector prior to its being operated with the specific goal of determining a performance baseline for planning future phases. These included alternative trapping configurations, with which the observed full width at half maximum has been improved to 3.6 eV. Evaluation of the event reconstruction and data quality are presented based on this data collection period. Areas where improvements will be required for phase II, when the approach will be used for the first time to measure a electrons from a continuous spectrum, are identified.

  14. Quality and yield of seven forages grown under partial shading of a simulated silvopastoral system in east Texas

    Science.gov (United States)

    J. Hill; K. Farrish; B. Oswald; L. Young; A. Shadow

    2016-01-01

    The goal of this project is to evaluate the growth and nutritional characteristics of seven forages, including various warm season native grasses, grown under simulated partial shading (50 percent typical of a loblolly pine silvopastoral system in east Texas. The results are from year two of a three year study. In order to meet the overall objective, individual,...

  15. An Archeological Overview and Management Plan for the Saginaw Army Aircraft Plant, Tarrant County, Texas.

    Science.gov (United States)

    1984-05-28

    included the Comanche, Kiowa, and Kiowa Apache ( Newcomb 1958). These were nomadic, equestrian tribes subsisting primary by large-scale communal bison...hunting. Typical set- S. tlements were camps, usually located along running water ( Newcomb 1958). K 2-6 0060D-6 Around AD 1700, Spanish Texas was invaded...Geological Survey Bulletin No. 12. Brown, Theodore M. 1981. German-Texas Study Unit. In Resource Protection Planning Process for Texas, by Theodore H. Brown

  16. STEREO and Wind Observations of Intense Cyclotron Harmonic Waves at the Earth's Bow Shock and Inside the Magnetosheath

    Science.gov (United States)

    Breneman, A. W.; Cattell, C.

    2013-01-01

    We present the first observations of electron cyclotron harmonic waves at the Earth's bow shock from STEREO and Wind burst waveform captures. These waves are observed at magnetic field gradients at a variety of shock geometries ranging from quasi-parallel to nearly perpendicular along with whistler mode waves, ion acoustic waves, and electrostatic solitary waves. Large amplitude cyclotron harmonic waveforms are also observed in the magnetosheath in association with magnetic field gradients convected past the bow shock. Amplitudes of the cyclotron harmonic waves range from a few tens to more than 500 millivolts/meter peak-peak. A comparison between the short (15 meters) and long (100 meters) Wind spin plane antennas shows a similar response at low harmonics and a stronger response on the short antenna at higher harmonics. This indicates that wavelengths are not significantly larger than 100 meters, consistent with the electron cyclotron radius. Waveforms are broadband and polarizations are distinctively comma-shaped with significant power both perpendicular and parallel to the magnetic field. Harmonics tend to be more prominent in the perpendicular directions. These observations indicate that the waves consist of a combination of perpendicular Bernstein waves and field-aligned waves without harmonics. A likely source is the electron cyclotron drift instability which is a coupling between Bernstein and ion acoustic waves. These waves are the most common type of high-frequency wave seen by STEREO during bow shock crossings and magnetosheath traversals and our observations suggest that they are an important component of the high-frequency turbulent spectrum in these regions.

  17. MC-50 AVF cyclotron operation

    Energy Technology Data Exchange (ETDEWEB)

    Chae, Jong Seo; Lee, Dong Hoon; Kim, You Seok; Park, Chan Won; Lee, Yong Min; Hong, Sung Seok; Lee, Min Yong

    1995-12-01

    The first cyclotron in Korea, MC-59 cyclotron is used for neutron irradiation, radionuclide development, production and material and biomedical research. 50.5MeV and 35MeV proton beam have been extracted with 20-70 .mu.A. A total of beam extraction time are 1095.7 hours. 206.5 hours are used for the developments and 663.8 hours are for radionuclide production and development and 225.4 hours for application researches. The shutdown days are 23days. Fundamental data for failure decrement and efficient beam extraction were composed and maintenance technologies were developed. (author). 8 tabs., 17 figs., 10 refs.

  18. MC-50 AVF cyclotron operation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yu Seok; Chai, Jong Seo; Bak, Seong Ki; Park, Chan Won; Jo, Young Ho; Hong, Seong Seok; Lee, Min Yong; Jang Ho Ha

    2000-01-01

    The first cyclotron in Korea, MC-50 cyclotron is used for neutron irradiation, radionuclide development, production and material and biomedical research. 50.5MeV and 35MeV proton beam have been extracted with 20-60{mu}A. A total of beam extraction time are 1095.7 hours. 206.5 hours are used for the developments and 663.8 hours are for radionuclide production and development and 225.4 hours for application researches. The shutdown days are 23 days. Fundamental data for failure decrement and efficient beam extraction were composed and maintenance technologies were developed.

  19. A Broadband Investigation of the Texas/Gulf of Mexico Passive Margin

    Science.gov (United States)

    Evanzia, D.; Ainsworth, R.; Pratt, K. W.; Pulliam, J.; Gurrola, H.

    2012-12-01

    The lithosphere of central and east Texas underwent two cycles of continental rifting and orogeny from the formation of Laurentia and assembly through the breakup of Pangea. The craton itself, exposed in the Llano uplift of central Texas, formed ~1.4 Ga as part of the great expanse of Mesoproterozoic crust that makes up southern Laurentia. Some of this crust was deformed during the Grenville orogeny ~1.1 Ga. Southern Laurentia was subsequently stable until rifting began in Cambrian time (~530 Ma). Suturing of Gondwana to Laurentia (310-290 Ma) during the assembly of Pangea formed the Ouachita orogen in west Texas. Sometime before 200 Ma rifting was initiated, opening the Gulf of Mexico (GoM). In north and east Texas the Ouachita front lies north of GoM rifting but, according to deep seismic data, Ouachita structures appear to coincide with GoM rifting in south and central Texas. This suggests that rifting in that region occurred along structures that were weakened previously by Ouachita deformation and reactivated during the Jurassic opening of the GoM. It is not clear whether the process that created the Gulf of Mexico and led to the formation of Texas' Gulf Coast Plain (GCP) is best described as "active" or "passive" rifting. A recent study interpreted the GCP to be a volcanic rifted margin—an active rifting process—using available gravity, magnetic, drilling and geological data, but older studies describe the opening of the GoM as a passive event. In the coastal plain, a large magnetic anomaly suggests that the crust here was modified by volcanism. Seismic data are sparse and of limited quality in the Gulf Coast region so we conducted a 2.5-year broadband seismograph transect across the GCP in an effort to clarify its structure and origin. In all, twenty-three broadband seismographs were deployed in a line from Matagorda Island, in the Gulf of Mexico, to Johnson City, TX, on the uplifted Llano Plateau from July 2010 to December 2012. These seismographs have

  20. The Berkeley accelerator space effects facility (BASE) - A newmission for the 88-inch cyclotron at LBNL

    Energy Technology Data Exchange (ETDEWEB)

    McMahan, M.A.

    2005-09-06

    In FY04, the 88-Inch Cyclotron began a new operating mode that supports a local research program in nuclear science, R&D in accelerator technology and a test facility for the National Security Space (NSS) community (the U.S. Air Force and NRO). The NSS community (and others on a cost recovery basis) can take advantage of both the light- and heavy-ion capabilities of the Cyclotron to simulate the space radiation environment. A significant portion of this work involves the testing of microcircuits for single event effects. The experimental areas within the building that are used for the radiation effects testing are now called the Berkeley Accelerator and Space Effects (BASE) facility. Improvements to the facility to provide increased reliability, quality assurance and new capabilities are underway and will be discussed. These include a 16 AMeV ''cocktail'' of beams for heavy ion testing, a neutron beam, more robust dosimetry, and other upgrades.

  1. Design of the ITER upper port electron cyclotron heating and current drive system based on remote steering

    NARCIS (Netherlands)

    M. F. Graswinckel,; van den Berg, M. A.; Bongers, W. A.; Donne, A. J. H.; Goede, A. P. H.; Cardozo, N. L.; Ronden, D. M. S.; Verhoeven, A. G. A.

    2008-01-01

    A design is presented for the electron cyclotron (EC) heating and current drive system of the ITER upper port launchers based on the remote steering (RS) concept. In this concept the millimeter-wave beam is steered by a mirror that is located at the back end of the launcher waveguide. The RS concept

  2. The Best Choice for a Prosperous Texas: A Texas-Style Personal Income Tax. Policy Brief No. 2

    Science.gov (United States)

    Center for Public Policy Priorities, 2006

    2006-01-01

    Part one of this trilogy of policy briefs explains the challenge facing Texas in funding public education. This policy brief explains why a Texas-style personal income tax is the best way to meet the needs of Texas. Only a personal income tax can significantly reduce reliance on property taxes--cutting the school operations tax from $1.50 to…

  3. Magnetic field and dimensionality-induced population effects in HgSe : Fe quantum wells: the cyclotron resonance

    Science.gov (United States)

    Portugall, O.; Barczewski, M.; von Ortenberg, M.; Schikora, D.; Widmer, T.; Lischka, H.

    1998-02-01

    Line shapes of the high-field cyclotron resonance are investigated both experimentally and theoretically for thin layers of the Fermi-level pinned system HgSe : Fe. Characteristic features are related to a subband population representing the two- and three-dimensional limits as well as intermediate steps.

  4. NuSTAR Discovery of a Cyclotron Line in KS 1947+300

    Science.gov (United States)

    Furst, Felix; Pottschmidt, Katja; Wilms, Jorn; Kennea, Jamie; Bachetti, Matteo; Bellm, Eric; Boggs, Steven E.; Chakrabarty, Deepto; Christensen, Finn E.; Craig, William W.; hide

    2014-01-01

    We present a spectral analysis of three simultaneous Nuclear Spectroscopy Telescope Array and Swift/XRT observations of the transient Be-neutron star binary KS 1947+300 taken during its outburst in 2013/2014. These broadband observations were supported by Swift/XRTmonitoring snapshots every three days, which we use to study the evolution of the spectrum over the outburst.We find strong changes of the power-law photon index, which shows a weak trend of softening with increasing X-ray flux. The neutron star shows very strong pulsations with a period of P ˜ [almost equal to] 18.8 s. The 0.8-79 keV broadband spectrum can be described by a power law with an exponential cutoff and a blackbody component at low energies. During the second observation we detect a cyclotron resonant scattering feature at 12.5 keV, which is absent in the phase-averaged spectra of observations 1 and 3. Pulse phase-resolved spectroscopy reveals that the strength of the feature changes strongly with pulse phase and is most prominent during the broad minimum of the pulse profile. At the same phases the line also becomes visible in the first and third observation at the same energy. This discovery implies that KS 1947+300 has a magnetic field strength of B ˜ [almost equal to] 1.1 × 1012(1 + z) G, which is at the lower end of known cyclotron line sources.

  5. Development of a low-level RF control system for PET cyclotron CYCIAE-14

    Science.gov (United States)

    Li, Pengzhan; Yin, Zhiguo; Ji, Bin; Zhang, Tianjue; Zhao, Zhenlu

    2014-01-01

    The project of a 14 MeV PET cyclotron aiming at medical diagnosis and treatment was proposed and started at CIAE in 2010. The low-level RF system is designed to stabilize acceleration voltage and control the resonance of the cavity. Based on the experience of the existing CRM Cyclotron in CIAE, a new start-up sequence is developed and tested. The frequency sweeping is used to activate the RF system. Before the tuner is put into use, a new state called "DDS tuning" is applied to trace the resonance frequency to the designed value. This new option state helps to cover the tuning range, if a large frequency variation occurs because of a thermal cavity deformation. The logic control unit detects the spark, reflection, Pulse/CW state and the frequency of the RF source to perform all kinds of protection and state operations. The test bench and on-line test are carried out to verify the initial design.

  6. Characteristic Experimentations of Degrader and Scatterer at MC-50 Cyclotron

    CERN Document Server

    Lee Seok Ki; Kim, Kye-Ryung; Lee, Hwa-Ryun; Park, Bum-Sik

    2005-01-01

    Building proton beam user facilities, especially deciding beam energy level, depends on the attached proton accelerator and users' needs. To adjust beam energy level, two methods are generally used. One is to directly adjust the beam in the accelerator. The other is to adjust beam energy after extracting from the accelerator. Degrader/Scatterer System has been installed in the MC-50 Cyclotron to adjust energy level of the beam used for various application fields. Its degrader and scatterer are made of Al foils and Au foils, respectively. Al thickness are 2, 1, 0.5, 0.3, 0.2, 0.1, 0.05, 0.03, 0.02, 0.01mm and Au thickness are 0.2, 0.1, 0.05, 0.03, 0.02, 0.01mm, respectively. In this study, suitable beam condition was adjusted through overlapping Al/Au foils of various thickness through simulation results. After that, LET(Linear Energy Transfer) value was indirectly acquired by measuring the bragg peak of the external beam through PMMA plastic Phantom and profile was measured by film dosimetry.

  7. Development of the Wink Sink in west Texas, U.S.A., due to salt dissolution and collapse

    Science.gov (United States)

    Johnson, K. S.

    1989-01-01

    The Wink Sink, in Winkler County, Texas, is a collapse feature that formed in June 1980 when an underground dissolution cavity migrated upward by successive roof failures until it breached the land surface. The original cavity developed in the Permian Salado Formation salt beds more than 400 m (1,300 ft) below ground level. Natural dissolution of salt occurred in the vicinity of the Wink Sink in several episodes that began as early as Salado time and recurred in later Permian, Triassic, and Cenozoic times. Although natural dissolution occurred in the past below the Wink Sink, it appears likely that the dissolution cavity and resultant collapse described in this report were influenced by petroleum-production activity in the immediate area. Drilling, completion, and plugging procedures used on an abandoned oil well at the site of the sink appear to have created a conduit that enabled water to circulate down the borehole and dissolve the salt. When the dissolution cavity became large enough, the roof failed and the overlying rocks collapsed into the cavity. Similar collapse features exist where underground salt beds have been intentionally dissolved during solution mining or accidentally dissolved as a result of petroleum-production activity. ?? 1989 Springer-Verlag New York Inc.

  8. Shielding for a cyclotron used for medical isotope production in China.

    Science.gov (United States)

    Pevey, R; Miller, L F; Marshall, B J; Townsend, L W; Alvord, B

    2005-01-01

    Monte Carlo and discrete ordinate calculations have been performed to determine the doses at several locations in a positron emission tomography (PET) facility in China, where the radiation source is a cyclotron that is used for the production of the isotopes necessary for PET scans. The energy-dependent neutron source term is obtained by calculations using the ALICE code, and is interpolated for input to Monte Carlo and discrete ordinate calculations. The building that houses the cyclotron has a labyrinth of walls to minimise dose to operators and to other occupants of the building. Unbiased Monte Carlo calculations did not converge after more than one week of CPU time, whereas direction biasing alone resulted in convergence in several days. A study of several biasing techniques indicated that about a factor of 3 in computational efficiency is obtained using evaluated biasing methods. The use of adjoint fluxes for biasing Monte Carlo calculations can improve computational efficiencies by one or two orders of magnitude for some problems.

  9. Ion cyclotron and spin-flip emissions from fusion products in tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Arunasalam, V.; Greene, G.J.; Young, K.M.

    1993-02-01

    Power emission by fusion products of tokamak plasmas in their ion cyclotron range of frequencies (ICRF) and at their spin-flip resonance frequency is calculated for some specific model fusion product velocity-space distribution functions. The background plasma of say deuterium (D) is assumed to be in equilibrium with a Maxwellian distribution both for the electrons and ions. The fusion product velocity distributions analyzed here are: (1) A monoenergetic velocity space ring distribution. (2) A monoenergetic velocity space spherical shell distribution. (3) An anisotropic Maxwellian distribution with T [perpendicular] [ne] T[parallel]and with appreciable drift velocity along the confining magnetic field. Single dressed'' test particle spontaneous emission calculations are presented first and the radiation temperature for ion cyclotron emission (ICE) is analyzed both for black-body emission and nonequilibrium conditions. Thresholds for instability and overstability conditions are then examined and quasilinear and nonlinear theories of the electromagnetic ion cyclotron modes are discussed. Distinctions between kinetic or causal instabilities'' and hydrodynamic instabilities'' are drawn and some numerical estimates are presented for typical tokamak parameters. Semiquantitative remarks are offered on wave accessibility, mode conversion, and parametric decay instabilities as possible for spatially localized ICE. Calculations are carried out both for k[parallel] = 0 for k[parallel] [ne] 0. The effects of the temperature anisotropy and large drift velocities in the parallel direction are also examined. Finally, proton spin-flip resonance emission and absorption calculations are also presented both for thermal equilibrium conditions and for an inverted'' population of states.

  10. Coupled operation of the Oak Ridge isochronous cyclotron and the 25 MV tandem

    Energy Technology Data Exchange (ETDEWEB)

    Lord, R.S.; Ball, J.B.; Beckers, R.M.; Cleary, T.P.; Hudson, E.D.; Ludemann, C.A.; Martin, J.A.; Milner, W.T.; Mosko, S.W.; Ziegler, N.F.

    1981-01-01

    Coupled operation of the 25 MV tandem and the Oak Ridge Isochronous Cyclotron (ORIC) was achieved on January 27, 1981. A beam of 38 MeV /sup 16/O/sup 2 +/ was injected into ORIC, stripped to 8/sup +/ and accelerated to 324 MeV. Shortly afterwards, the energy was increased to the maximum design value of 25 MeV/amu (400 MeV). A spectrum taken of the scattering of this beam from a thin /sup 208/Pb target in the broad range spectrograh exhibited a resolution of 115 keV (FWHM). Performance of the system was in close agreement with that predicted from calculations.

  11. OPERATION OF A PUBLIC GEOLOGIC CORE AND SAMPLE REPOSITORY IN HOUSTON, TEXAS

    Energy Technology Data Exchange (ETDEWEB)

    Scott W. Tinker; Beverly Blakeney DeJarnett; Laura C. Zahm

    2005-04-01

    The Bureau of Economic Geology's Houston Research Center (HRC) is well established as a premier regional research center for geologic research serving not only Houston, but geoscientists from around Texas, the U. S., and even the world. As reported in the 2003-2004 technical progress report to the DOE, the HRC provides a state-of-the-art core viewing facility, two fully equipped conference rooms, and a comprehensive technical library, all available for public use. In addition, the HRC currently houses over 500,000 boxes of rock material, and has space to hold approximately 400,000 more boxes. Use of the facility has continued to increase during this third year of operation; over the past twelve months the HRC has averaged approximately 200 patrons per month. This usage is a combination of individuals describing core, groups of geoscientists holding seminars and workshops, and various industry and government-funded groups holding short courses, workshops, and seminars. The BEG/HRC secured several substantial donations of rock materials and/or cash during this operating period. All of these funds went directly into the endowment. Outreach during 2004 and 2005 included many technical presentations and several publications on the HRC. Several field trips to the facility were held for geoscience professionals and grade school students alike. Goals for the upcoming year involve securing more donations of rock material and cash in order to fully fund the HRC endowment. BEG will also continue to increase the number of patrons using the facility, and we will strive to raise awareness of the HRC's 100,000-volume geoscience technical library.

  12. The electrostatic ion-cyclotron instability excited by a current to a strip collector

    DEFF Research Database (Denmark)

    Juul Rasmussen, Jens; Schrittwieser, R.; Skøelv, Å.

    1986-01-01

    The electrostatic ion-cyclotron instability is excited in a single-ended Q-machine by drawing an electron current to a strip collector crossing the entire plasma column. The instability is most easily excited when the widths of the strip is a few ion Larmor radii. The instability is confined within...

  13. Calculating method for confinement time and charge distribution of ions in electron cyclotron resonance sources

    Energy Technology Data Exchange (ETDEWEB)

    Dougar-Jabon, V.D. [Escuela de Fisica, Universidad Industrial de Santander, A.A. 678, Bucaramanga (Colombia); Umnov, A.M. [Russian Friendship University, 117198 Moscow (Russia); Kutner, V.B. [Joint Institute for Nuclear Research, Dubna (Russia)

    1996-03-01

    It is common knowledge that the electrostatic pit in a core plasma of electron cyclotron resonance sources exerts strict control over generation of ions in high charge states. This work is aimed at finding a dependence of the lifetime of ions on their charge states in the core region and to elaborate a numerical model of ion charge dispersion not only for the core plasmas but for extracted beams as well. The calculated data are in good agreement with the experimental results on charge distributions and magnitudes for currents of beams extracted from the 14 GHz DECRIS source. {copyright} {ital 1996 American Institute of Physics.}

  14. Restoration of accelerator facilities damaged by Great East Japan Earthquake at Cyclotron and Radioisotope Center, Tohoku University.

    Science.gov (United States)

    Wakui, Takashi; Itoh, Masatoshi; Shimada, Kenzi; Yoshida, Hidetomo P; Shinozuka, Tsutomu; Sakemi, Yasuhiro

    2014-08-01

    The Cyclotron and Radioisotope Center (CYRIC) of Tohoku University is a joint-use institution for education and research in a wide variety of fields ranging from physics to medicine. Accelerator facilities at the CYRIC provide opportunities for implementing a broad research program, including medical research using positron emission tomography (PET), with accelerated ions and radioisotopes. At the Great East Japan Earthquake on March 11, 2011, no human injuries occurred and a smooth evacuation was made in the CYRIC, thanks to the anti-earthquake measures such as the renovation of the cyclotron building in 2009 mainly to provide seismic strengthening, fixation of shelves to prevent the falling of objects, and securement of the width of the evacuation route. The preparation of an emergency response manual was also helpful. However, the accelerator facilities were damaged because of strong shaking that continued for a few minutes. For example, two columns on which a 930 cyclotron was placed were damaged, and thereby the 930 cyclotron was inclined. All the elements of beam transport lines were deviated from the beam axis. Some peripheral devices in a HM12 cyclotron were broken. Two shielding doors fell from the carriage onto the floor and blocked the entrances to the rooms. The repair work on the accelerator facilities was started at the end of July 2011. During the repair work, the joint use of the accelerator facilities was suspended. After the repair work was completed, the joint use was re-started at October 2012, one and a half years after the earthquake.

  15. Prediction of neutron induced radioactivity in the concrete walls of a PET cyclotron vault room with MCNPX.

    Science.gov (United States)

    Martínez-Serrano, J Javier; Díez de los Ríos, Antonio

    2010-11-01

    The authors want to assess the relevance of the neutron activation of the concrete vault of the PET cyclotron at CIMES (Universidad de Malaga) by predicting specific activities of the main activation products in the vault and their variation profiles as a function of penetration depth into concrete at present and after 10 yr of cyclotron operation. The dual proton cyclotron is used for PET isotopes production, mainly 18F. During the years 2006 and 2008, the using rate has been 1 h/day at single beam (40 microA). From January 2008, using rate is 4 h/day at dual beam (80 microA). The energy of the cyclotron proton beam is 18 MeV. Four point locations were chosen on the walls of the cyclotron room to assess neutron induced activity concentrations. In each wall point location, neutron induced radionuclide specific activity was assessed from the wall surface to a depth of 120 cm within concrete. Simulations were carried out with the Monte Carlo based radiation transport code MCNPX (v2.6.0). According to MCNPX calculations, activity depth profiles of activation products studied, except 54Mn, have a maximum at variable depths from the wall surface never beyond 12 cm. 54Mn activity decreases exponentially in all the studied depth ranges within wall concrete. The activity of 152Eu, 154Eu, 60CO, 134Cs, 46Sc, and 65Zn decreases exponentially beyond a 30 cm depth into concrete. 54Mn activity presents the faster decrease within a concrete vault with an attenuation length of 21 cm. According to MCNPX estimations, present activity in the cyclotron vault is mostly due to 46Sc and 60Co, with highest specific activity near the vault surface of 146 +/- 16 and 50 +/- 4.6 Bq/kg, respectively. 46Sc and 60Co activity measurements near the surface wall present an acceptable match with the estimation within the uncertainties, but measured activities of the other radionuclides are quite over the MCNPX estimations. The calculations after 10 yr of cyclotron operation predict a slight increase

  16. Accurate Monte Carlo modeling of cyclotrons for optimization of shielding and activation calculations in the biomedical field

    Science.gov (United States)

    Infantino, Angelo; Marengo, Mario; Baschetti, Serafina; Cicoria, Gianfranco; Longo Vaschetto, Vittorio; Lucconi, Giulia; Massucci, Piera; Vichi, Sara; Zagni, Federico; Mostacci, Domiziano

    2015-11-01

    Biomedical cyclotrons for production of Positron Emission Tomography (PET) radionuclides and radiotherapy with hadrons or ions are widely diffused and established in hospitals as well as in industrial facilities and research sites. Guidelines for site planning and installation, as well as for radiation protection assessment, are given in a number of international documents; however, these well-established guides typically offer analytic methods of calculation of both shielding and materials activation, in approximate or idealized geometry set up. The availability of Monte Carlo codes with accurate and up-to-date libraries for transport and interactions of neutrons and charged particles at energies below 250 MeV, together with the continuously increasing power of nowadays computers, makes systematic use of simulations with realistic geometries possible, yielding equipment and site specific evaluation of the source terms, shielding requirements and all quantities relevant to radiation protection. In this work, the well-known Monte Carlo code FLUKA was used to simulate two representative models of cyclotron for PET radionuclides production, including their targetry; and one type of proton therapy cyclotron including the energy selection system. Simulations yield estimates of various quantities of radiological interest, including the effective dose distribution around the equipment, the effective number of neutron produced per incident proton and the activation of target materials, the structure of the cyclotron, the energy degrader, the vault walls and the soil. The model was validated against experimental measurements and comparison with well-established reference data. Neutron ambient dose equivalent H*(10) was measured around a GE PETtrace cyclotron: an average ratio between experimental measurement and simulations of 0.99±0.07 was found. Saturation yield of 18F, produced by the well-known 18O(p,n)18F reaction, was calculated and compared with the IAEA recommended

  17. Assessment of single-turn extraction for a superconducting separated-sector cyclotron

    Directory of Open Access Journals (Sweden)

    J.-W. Kim

    1999-04-01

    Full Text Available We have studied the beam dynamics in a high field separated-sector cyclotron to establish conditions required to achieve single-turn extraction. Extraction efficiency above 99% is aimed to avoid beam-induced damages. A sufficient last-turn separation and a preservation of beam quality throughout the acceleration are the prerequisites. The last-turn separation can be enhanced with the orbital precession induced by an off-centering injection as in existent lower field separated-sector cyclotrons. The beam qualities, on the other hand, are affected by the resonances traversed or approached during the acceleration. Acceleration of light nuclei to the energies of 300–400 MeV/u was especially disturbing because of the broadening of radial beamwidth upon crossing the ν_{r}=3/2 resonance. Tolerance to the third harmonic gradient field, which causes the resonance in lowest order, is set to be 0.1 G/cm. The integer resonance ν_{z}=1 can be avoided with a proper design of the yoke. The longitudinal space charge forces were also investigated to estimate the intensity limits determined by the energy spreads of beam assuming simplified charge distributions. Moreover, beam preparations for injection matching are described in view of reducing the beam losses into the extraction elements.

  18. Cyclotron axial ion-beam-buncher system

    Energy Technology Data Exchange (ETDEWEB)

    Hamm, R.W.; Swenson, D.A.; Wangler, T.P.

    1982-02-11

    Adiabatic ion bunching is achieved in a cyclotron axial ion injection system through the incorporation of a radio frequency quadrupole system, which receives ions from an external ion source via an accelerate-decelerate system and a focusing einzel lens system, and which adiabatically bunches and then injects the ions into the median plane of a cyclotron via an electrostatic quadrupole system and an inflection mirror.

  19. A study on the irradiation effect of reactor materials using a cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Joon Hwa; Ji, Se Hwan; Kang, Yung Hwan; Park, Duk Keun; Park, Jong Man; Lee, Bong Sang; Oh, Jong Myung [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1994-12-01

    The objectives of the present study are to develop the simulation techniques of neutron irradiation through ion irradiation using a Cyclotron and small specimen techniques and to evaluate radiation effects of reactor materials. Effects of proton or neutron irradiation on domestic 12Cr-1MoV and SA508-3 steels were evaluated by small scale specimen test techniques, i.e, small punch and miniaturized tensile test. In order to study the radiation damage mechanism, irradiation effects of the steels were investigated by means of property change tests such as microstructure, physical and thermal properties. Feasibility study on application of a magnetic non-destructive methods to evaluate radiation effects on RPV materials was performed. 109 figs, 12 tabs, 102 refs. (Author).

  20. The electrostatic ion-cyclotron instability-a two-dimensional potential relaxation instability

    DEFF Research Database (Denmark)

    Popa, G.; Schrittwieser, R.; Juul Rasmussen, Jens

    1985-01-01

    An experimental investigation shows that the electrostatic ion-cyclotron instability, driven by an electron current to a positively biased collector, is accompanied by strong coherent two-dimensional fluctuations of the plasma potential in front of the collector. These results suggest that this i......An experimental investigation shows that the electrostatic ion-cyclotron instability, driven by an electron current to a positively biased collector, is accompanied by strong coherent two-dimensional fluctuations of the plasma potential in front of the collector. These results suggest...

  1. Promises of cyclotron-produced 44Sc as a diagnostic match for trivalent β--emitters: in vitro and in vivo study of a 44Sc-DOTA-folate conjugate.

    Science.gov (United States)

    Müller, Cristina; Bunka, Maruta; Reber, Josefine; Fischer, Cindy; Zhernosekov, Konstantin; Türler, Andreas; Schibli, Roger

    2013-12-01

    In recent years, implementation of (68)Ga-radiometalated peptides for PET imaging of cancer has attracted the attention of clinicians. Herein, we propose the use of (44)Sc (half-life = 3.97 h, average β(+) energy [Eβ(+)av] = 632 keV) as a valuable alternative to (68)Ga (half-life = 68 min, Eβ(+)av = 830 keV) for imaging and dosimetry before (177)Lu-based radionuclide therapy. The aim of the study was the preclinical evaluation of a folate conjugate labeled with cyclotron-produced (44)Sc and its in vitro and in vivo comparison with the (177)Lu-labeled pendant. (44)Sc was produced via the (44)Ca(p,n)(44)Sc nuclear reaction at a cyclotron (17.6 ± 1.8 MeV, 50 μA, 30 min) using an enriched (44)Ca target (10 mg (44)CaCO3, 97.00%). Separation from the target material was performed by a semiautomated process using extraction chromatography and cation exchange chromatography. Radiolabeling of a DOTA-folate conjugate (cm09) was performed at 95°C within 10 min. The stability of (44)Sc-cm09 was tested in human plasma. (44)Sc-cm09 was investigated in vitro using folate receptor-positive KB tumor cells and in vivo by PET/CT imaging of tumor-bearing mice Under the given irradiation conditions, (44)Sc was obtained in a maximum yield of 350 MBq at high radionuclide purity (>99%). Semiautomated isolation of (44)Sc from (44)Ca targets allowed formulation of up to 300 MBq of (44)Sc in a volume of 200-400 μL of ammonium acetate/HCl solution (1 M, pH 3.5-4.0) within 10 min. Radiolabeling of cm09 was achieved with a radiochemical yield of greater than 96% at a specific activity of 5.2 MBq/nmol. In vitro, (44)Sc-cm09 was stable in human plasma over the whole time of investigation and showed folate receptor-specific binding to KB tumor cells. PET/CT images of mice injected with (44)Sc-cm09 allowed excellent visualization of tumor xenografts. Comparison of cm09 labeled with (44)Sc and (177)Lu revealed almost identical pharmacokinetics. This study presents a high-yield production and

  2. Synchro-cyclotron

    CERN Multimedia

    CERN PhotoLab

    1972-01-01

    The electromagnetic coil which forms the first section of the proton extraction channel in the improved synchro-cyclotron. The photograph shows the positioning gear and the current septum. An extraction efficiency above 50% is expected.

  3. GEANT4 simulation of cyclotron radioisotope production in a solid target.

    Science.gov (United States)

    Poignant, F; Penfold, S; Asp, J; Takhar, P; Jackson, P

    2016-05-01

    The use of radioisotopes in nuclear medicine is essential for diagnosing and treating cancer. The optimization of their production is a key factor in maximizing the production yield and minimizing the associated costs. An efficient approach to this problem is the use of Monte Carlo simulations prior to experimentation. By predicting isotopes yields, one can study the isotope of interest expected activity for different energy ranges. One can also study the target contamination with other radioisotopes, especially undesired radioisotopes of the wanted chemical element which are difficult to separate from the irradiated target and might result in increasing the dose when delivering the radiopharmaceutical product to the patient. The aim of this work is to build and validate a Monte Carlo simulation platform using the GEANT4 toolkit to model the solid target system of the South Australian Health and Medical Research Institute (SAHMRI) GE Healthcare PETtrace cyclotron. It includes a GEANT4 Graphical User Interface (GUI) where the user can modify simulation parameters such as the energy, shape and current of the proton beam, the target geometry and material, the foil geometry and material and the time of irradiation. The paper describes the simulation and presents a comparison of simulated and experimental/theoretical yields for various nuclear reactions on an enriched nickel 64 target using the GEANT4 physics model QGSP_BIC_AllHP, a model recently developed to evaluate with high precision the interaction of protons with energies below 200MeV available in Geant4 version 10.1. The simulation yield of the (64)Ni(p,n)(64)Cu reaction was found to be 7.67±0.074 mCi·μA(-1) for a target energy range of 9-12MeV. Szelecsenyi et al. (1993) gives a theoretical yield of 6.71mCi·μA(-1) and an experimental yield of 6.38mCi·μA(-1). The (64)Ni(p,n)(64)Cu cross section obtained with the simulation was also verified against the yield predicted from the nuclear database TENDL and

  4. Verification of effectiveness of borated water shield for a cyclotron type self-shielded; Verificacao da eficacia da blindagem de agua borada construida para um acelerador ciclotron do tipo autoblindado

    Energy Technology Data Exchange (ETDEWEB)

    Videira, Heber S.; Burkhardt, Guilherme M.; Santos, Ronielly S., E-mail: heber@cyclopet.com.br [Cyclopet Radiofarmacos Ltda., Curitiba, PR (Brazil); Passaro, Bruno M.; Gonzalez, Julia A.; Santos, Josefina; Guimaraes, Maria I.C.C. [Universidade de Sao Paulo (HCFMRP/USP), Sao Paulo, SP (Brazil). Faculdade de Medicina. Hospital das Clinicas; Lenzi, Marcelo K. [Universidade Federal do Parana (UFPR), Curitina (Brazil). Programa de Pos-Graduacao em Engenharia Quimica

    2013-04-15

    The technological advances in positron emission tomography (PET) in conventional clinic imaging have led to a steady increase in the number of cyclotrons worldwide. Most of these cyclotrons are being used to produce {sup 18}F-FDG, either for themselves as for the distribution to other centers that have PET. For there to be safety in radiological facilities, the cyclotron intended for medical purposes can be classified in category I and category II, ie, self-shielded or non-shielded (bunker). Therefore, the aim of this work is to verify the effectiveness of borated water shield built for a cyclotron accelerator-type Self-shielded PETtrace 860. Mixtures of water borated occurred in accordance with the manufacturer’s specifications, as well as the results of the radiometric survey in the vicinity of the self-shielding of the cyclotron in the conditions established by the manufacturer showed that radiation levels were below the limits. (author)

  5. Cyclotron transitions of bound ions

    Science.gov (United States)

    Bezchastnov, Victor G.; Pavlov, George G.

    2017-06-01

    A charged particle in a magnetic field possesses discrete energy levels associated with particle rotation around the field lines. The radiative transitions between these levels are the well-known cyclotron transitions. We show that a bound complex of particles with a nonzero net charge displays analogous transitions between the states of confined motion of the entire complex in the field. The latter bound-ion cyclotron transitions are affected by a coupling between the collective and internal motions of the complex and, as a result, differ from the transitions of a "reference" bare ion with the same mass and charge. We analyze the cyclotron transitions for complex ions by including the coupling within a rigorous quantum approach. Particular attention is paid to comparison of the transition energies and oscillator strengths to those of the bare ion. Selection rules based on integrals of collective motion are derived for the bound-ion cyclotron transitions analytically, and the perturbation and coupled-channel approaches are developed to study the transitions quantitatively. Representative examples are considered and discussed for positive and negative atomic and cluster ions.

  6. Living on a Cotton Farm: Mexican American Life in Texas.

    Science.gov (United States)

    Black, Mary S.

    This packet of six lesson plans highlights Mexican-American life on a Texas cotton farm in the early 20th century. Each lesson provides a lesson overview; states educational objectives; cites materials needed; details the procedure for classroom implementation; offers a closure activity; and suggests an extension activity. The packet is divided…

  7. Degrees of Separation: Latino Students' Transitions to a Texas HBCU

    Science.gov (United States)

    Allen, Taryn Ozuna; Stone, Ashley N.

    2016-01-01

    A successful transition to college is the foundation for future academic success, and this process is particularly important for a quickly growing Latino population. This qualitative study explored the transitional experiences of eight Latino students who enrolled in a historically Black university in Texas. Focusing specifically on their…

  8. Proposal and verification numerical simulation for a microwave forward scattering technique at upper hybrid resonance for the measurement of electron gyroscale density fluctuations in the electron cyclotron frequency range in magnetized plasmas

    Science.gov (United States)

    Kawamori, E.; Igami, H.

    2017-11-01

    A diagnostic technique for detecting the wave numbers of electron density fluctuations at electron gyro-scales in an electron cyclotron frequency range is proposed, and the validity of the idea is checked by means of a particle-in-cell (PIC) numerical simulation. The technique is a modified version of the scattering technique invented by Novik et al. [Plasma Phys. Controlled Fusion 36, 357-381 (1994)] and Gusakov et al., [Plasma Phys. Controlled Fusion 41, 899-912 (1999)]. The novel method adopts forward scattering of injected extraordinary probe waves at the upper hybrid resonance layer instead of the backward-scattering adopted by the original method, enabling the measurement of the wave-numbers of the fine scale density fluctuations in the electron-cyclotron frequency band by means of phase measurement of the scattered waves. The verification numerical simulation with the PIC method shows that the technique has a potential to be applicable to the detection of electron gyro-scale fluctuations in laboratory plasmas if the upper-hybrid resonance layer is accessible to the probe wave. The technique is a suitable means to detect electron Bernstein waves excited via linear mode conversion from electromagnetic waves in torus plasma experiments. Through the numerical simulations, some problems that remain to be resolved are revealed, which include the influence of nonlinear processes such as the parametric decay instability of the probe wave in the scattering process, and so on.

  9. Insurance Coverage, Access to Care, and Medical Debt Since the ACA: a Look at California, Florida, New York, and Texas.

    Science.gov (United States)

    Gunja, Munira Z; Collins, Sara R; Doty, Michelle McEvoy; Beutel, Sophie

    2017-03-01

    ISSUE: The Affordable Care Act has significantly increased health insurance coverage and access to care among U.S. adults nationwide. However, the law gives states flexibility in implementing certain provisions, leading to wide variations between states in consumers’ experiences. GOAL: To examine the differences in insurance coverage, access to care, and medical bill problems in the four largest states—California, Florida, New York, and Texas—all of which have made different choices in implementing the law. METHODS: Analysis of the Commonwealth Fund Biennial Health Insurance Survey, 2016. FINDINGS AND CONCLUSIONS: In 2016, uninsured rates among adults ages 19 to 64 across the four states varied from 7 percent in New York and 10 percent in California to 16 percent in Florida and 25 percent in Texas. This variation was also apparent in the proportions of residents reporting problems getting needed care because of the cost—significantly lower in California and New York than in Florida and Texas. Lower percentages of Californians and New Yorkers reported having a medical bill problem in the past 12 months or having accrued medical debt compared to Floridians and Texans. These variations might be explained by several factors: whether the state expanded Medicaid eligibility; whether it ran its own health insurance marketplace; what the uninsured rate was prior to the Affordable Care Act; differences in the cost protections provided by private health plans; and demographic differences.

  10. Enhanced Physicochemical and Biological Properties of Ion-Implanted Titanium Using Electron Cyclotron Resonance Ion Sources

    Directory of Open Access Journals (Sweden)

    Csaba Hegedűs

    2016-01-01

    Full Text Available The surface properties of metallic implants play an important role in their clinical success. Improving upon the inherent shortcomings of Ti implants, such as poor bioactivity, is imperative for achieving clinical use. In this study, we have developed a Ti implant modified with Ca or dual Ca + Si ions on the surface using an electron cyclotron resonance ion source (ECRIS. The physicochemical and biological properties of ion-implanted Ti surfaces were analyzed using various analytical techniques, such as surface analyses, potentiodynamic polarization and cell culture. Experimental results indicated that a rough morphology was observed on the Ti substrate surface modified by ECRIS plasma ions. The in vitro electrochemical measurement results also indicated that the Ca + Si ion-implanted surface had a more beneficial and desired behavior than the pristine Ti substrate. Compared to the pristine Ti substrate, all ion-implanted samples had a lower hemolysis ratio. MG63 cells cultured on the high Ca and dual Ca + Si ion-implanted surfaces revealed significantly greater cell viability in comparison to the pristine Ti substrate. In conclusion, surface modification by electron cyclotron resonance Ca and Si ion sources could be an effective method for Ti implants.

  11. Theory and observations of electromagnetic ion cyclotron waves in Saturn's inner magnetosphere

    Science.gov (United States)

    Barbosa, D. D.

    1993-01-01

    High-resolution Voyager 1 magnetic field observations of Saturn's inner magnetosphere are examined for the presence of ULF waves. Quasi-circular left-hand polarized transverse oscillations are found in the near-equatorial region of 5-7 Rs with a wave period about 10 s and peak amplitude of about 2 nT. The wave is identified as the electromagnetic oxygen cyclotron mode occurring at a frequency just below the O(+) ion cyclotron frequency. A theoretical model of wave excitation based on gyroresonant coupling through a temperature anisotropy of O(+) pickup ions is developed which accounts for the principal features of the wave spectrum. It is hypothesized that wave-particle interactions provide a level of scattering commensurate with the weak pitch angle diffusion regime but nonetheless one that regulates and maintains a constant thermal anisotropy of ions along the magnetic field. Arguments are also presented that O(+) was the dominant thermal ion of the Dione-Tethys plasma torus at the time of the Pioneer 11 encounter the year previous to the Voyager 1 measurements.

  12. Source, variability, and transformation of nitrate in a regional karst aquifer: Edwards aquifer, central Texas

    Energy Technology Data Exchange (ETDEWEB)

    Musgrove, M., E-mail: mmusgrov@usgs.gov [U.S. Geological Survey, 1505 Ferguson Lane, Austin, TX 78754 (United States); Opsahl, S.P. [U.S. Geological Survey, 5563 DeZavala, Ste. 290, San Antonio, TX 78249 (United States); Mahler, B.J. [U.S. Geological Survey, 1505 Ferguson Lane, Austin, TX 78754 (United States); Herrington, C. [City of Austin Watershed Protection Department, Austin, TX 78704 (United States); Sample, T.L. [U.S. Geological Survey, 19241 David Memorial Dr., Ste. 180, Conroe, TX 77385 (United States); Banta, J.R. [U.S. Geological Survey, 5563 DeZavala, Ste. 290, San Antonio, TX 78249 (United States)

    2016-10-15

    Many karst regions are undergoing rapid population growth and expansion of urban land accompanied by increases in wastewater generation and changing patterns of nitrate (NO{sub 3}{sup −}) loading to surface and groundwater. We investigate variability and sources of NO{sub 3}{sup −} in a regional karst aquifer system, the Edwards aquifer of central Texas. Samples from streams recharging the aquifer, groundwater wells, and springs were collected during 2008–12 from the Barton Springs and San Antonio segments of the Edwards aquifer and analyzed for nitrogen (N) species concentrations and NO{sub 3}{sup −} stable isotopes (δ{sup 15}N and δ{sup 18}O). These data were augmented by historical data collected from 1937 to 2007. NO{sub 3}{sup −} concentrations and discharge data indicate that short-term variability (days to months) in groundwater NO{sub 3}{sup −} concentrations in the Barton Springs segment is controlled by occurrence of individual storms and multi-annual wet-dry cycles, whereas the lack of short-term variability in groundwater in the San Antonio segment indicates the dominance of transport along regional flow paths. In both segments, longer-term increases (years to decades) in NO{sub 3}{sup −} concentrations cannot be attributed to hydrologic conditions; rather, isotopic ratios and land-use change indicate that septic systems and land application of treated wastewater might be the source of increased loading of NO{sub 3}{sup −}. These results highlight the vulnerability of karst aquifers to NO{sub 3}{sup −} contamination from urban wastewater. An analysis of N-species loading in recharge and discharge for the Barton Springs segment during 2008–10 indicates an overall mass balance in total N, but recharge contains higher concentrations of organic N and lower concentrations of NO{sub 3}{sup −} than does discharge, consistent with nitrification of organic N within the aquifer and consumption of dissolved oxygen. This study demonstrates

  13. Ammonia-treated N-(1-naphthyl) ethylenediamine dihydrochloride as a novel matrix for rapid quantitative and qualitative determination of serum free fatty acids by matrix-assisted laser desorption/ionization-Fourier transform ion cyclotron resonance mass spectrometry.

    Science.gov (United States)

    Zhang, Yaping; Wang, Yanmin; Guo, Shuai; Guo, Yumei; Liu, Hui; Li, Zhili

    2013-09-10

    The blood free fatty acids (FFAs), which provide energy to the cell and act as substrates in the synthesis of fats, lipoproteins, liposaccharides, and eicosanoids, involve in a number of important physiological processes. In the present study, matrix-assisted laser desorption/ionization-Fourier transform ion cyclotron resonance mass spectrometry (MALDI-FTICR MS) with ammonia-treated N-(1-naphthyl) ethylenediamine dihydrochloride (ATNEDC) as a novel MALDI matrix in a negative ion mode was employed to directly quantify serum FFAs. Multiple point internal standard calibration curves between the concentration ratios of individual fatty acids to internal standard (IS, C17:0) versus their corresponding intensity ratios were constructed for C14:0, C16:1, C16:0, C18:0, C18:1, C18:2, C18:3, C20:4, and C22:6, respectively, in their mixture, with correlation coefficients between 0.991 and 0.999 and limits of detection (LODs) between 0.2 and 5.4μM, along with the linear dynamic range of more than two orders of magnitude. The results indicate that the multiple point internal standard calibration could reduce the impact of ion suppression and improve quantification accuracy in the MALDI mode. The quantitative results of nine FFAs from 339 serum samples, including 161 healthy controls, 118 patients with hyperglycemia and 60 patients without hyperglycemia show that FFAs levels in hyperglycemic patient sera are significantly higher than those in healthy controls and patients without hyperglycemia, and elevated FFA levels are also associated with increased levels of fasting blood glucose (FBG) in hyperglycemic patient sera. Serum FFAs were identified on the basis of the observed accurate molecular masses and reliable isotope distributions obtained by MALDI-FTICR MS. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. Verification of the shielding built for a Cyclotron accelerator; Verificacao da blindagem construida para um acelerador do tipo Ciclotron

    Energy Technology Data Exchange (ETDEWEB)

    Videira, Heber S., E-mail: heber@cyclopet.com [CYCLOPET Radiofarmacos LTDA., Curitiba, PR (Brazil); Passaro, Bruno M.; Gonzalez, Julia A.; Guimaraes, Maria Ines C.C.; Buchpigue, Carlos A. [Centro de Medicina Nuclear (CMN) do InRad HCFMUSP, Sao Paulo, SP (Brazil)

    2012-08-15

    According to the National Nuclear Energy Commission (CNEN) resolution 112/2011, administrative controls must be applied during the construction of a cyclotron and documents must be created showing that the facility can operate without radiological risks, referring even to the shielding efficiency. This study aimed to perform the analysis of the construction and efficiency of the bunker built for shielding, in the cyclotron of University of Sao Paulo Medical School Health System. This was possible through the measurements of a radiometric survey in normal working conditions, and testing related to compression resistance and density. The results showed that the compression resistance of the concrete used is higher than the expected value and the average density value obtained is within the tolerated limits. The radiometric survey results showed that the levels of ionizing radiation are well below the established limits. (author)

  15. Long-term cyclotron dynamics of relativistic wave packets: Spontaneous collapse and revival

    Science.gov (United States)

    Demikhovskii, V. Ya.; Maksimova, G. M.; Perov, A. A.; Telezhnikov, A. V.

    2012-02-01

    In this work we study the effects of collapse and revival, as well as the zitterbewegung (ZB) phenomenon, for the relativistic electron wave packets, which are a superposition of the states with quantum numbers sharply peaked around some Landau level n0 of the order of few tens. The probability densities as well as average velocities of the packet center and the average spin components were calculated analytically and their evolution is visualized. Our computations demonstrate that due to the dephasing of the states for times larger than the cyclotron period the initial wave packet (which includes the states with the positive energy only) loses the spatial localization so that the evolution can no longer be described classically. However, at the half-revival time t=TR/2 its reshaping takes place first. It is shown that the behavior of the wave packet containing the states of both energy bands (with En>0 and Ennegative energy) restores at various points of the cyclotron orbit, which makes reshaping of the initial wave packet impossible, entirely unlike the wave packet which consists of states with energies En>0 only. The obtained results can be useful for the description of electromagnetic radiation and absorption in relativistic plasma on astrophysics objects, where superhigh magnetic field has a value of the order 108-109T, as well as for interpretation of experiments with trapped ions.

  16. Preeclampsia mortality in Texas: a capture-recapture analysis.

    Science.gov (United States)

    Eziefule, Akwugo A; Martinez, Carla A; Mulla, Zuber D

    2011-01-01

    Public health professionals and clinicians rely on hospital discharge data to explore the epidemiology of preeclampsia. Our objective was to compare the concordance in preeclampsia inpatient mortality between hospital inpatient discharge data and death certificate data in Texas during a 2-year period using the capture-recapture technique. The statewide Texas hospital inpatient discharge dataset and a statewide death certificate dataset were searched for fatal episodes of preeclampsia or eclampsia. Women who were Texas residents and expired in a hospital in 2006 or 2007 were identified using ICD-9-CM and ICD-10 codes. Using the capture-recapture sampling technique, we estimated the number of inpatient preeclamptic deaths that were missed by both databases, the death certificate database and the hospital inpatient database. The hospital inpatient dataset captured 17 fatal episodes of preeclampsia while the inpatient death certificate database captured 9. Six patients were found in both datasets. Application of the capture-recapture method revealed that the total number of statewide inpatient preeclamptic deaths was 26 during this period. This pilot study found that 2 prominent sources of statewide health data underestimated the frequency of inpatient deaths in Texas due to preeclampsia.

  17. The study of acceptance and the transmission efficiency of separated sector cyclotron

    Directory of Open Access Journals (Sweden)

    Li Xiaoni

    2015-01-01

    Full Text Available In this paper we present the study of the transversal and longitudinal acceptance and the transmission efficiency in the injection, acceleration, and extraction systems in the separated sector cyclotron of the heavy ion research facility in Lanzhou, China. The study of cyclotron acceptance is done for 238U36+ with energy of 97 MeV/u and for 70Zn10+ with energy of 5.62 MeV/u under the theoretical isochronous and real magnetic field distribution. From the simulation results it can be seen that the transmission efficiency and the acceptances of separated sector cyclotron can be improved by redesign the curvature of MSI3 deflector or by introducing the magnet shim in MSI3 deflector region to change the distribution of the inner magnetic field. [Projekat Ministarstva nauke Republike Srbije, br. OI-171018

  18. Distribution of residual long-lived radioactivity in the inner concrete walls of a compact medical cyclotron vault room.

    Science.gov (United States)

    Fujibuchi, Toshioh; Nohtomi, Akihiro; Baba, Shingo; Sasaki, Masayuki; Komiya, Isao; Umedzu, Yoshiyuki; Honda, Hiroshi

    2015-01-01

    Compact medical cyclotrons have been set up to generate the nuclides necessary for positron emission tomography. In accelerator facilities, neutrons activate the concrete used to construct the vault room; this activation increases with the use of an accelerator. The activation causes a substantial radioactive waste management problem when facilities are decommissioned. In the present study, several concrete cores from the walls, ceiling and floor of a compact medical cyclotron vault room were samples 2 years after the termination of operations, and the radioactivity concentrations of radionuclides were estimated. Cylindrical concrete cores 5 cm in diameter and 10 cm in length were bored from the concrete wall, ceiling and floor. Core boring was performed at 18 points. The gamma-ray spectrum of each sample was measured using a high-purity germanium detector. The degree of activation of the concrete in the cyclotron vault room was analyzed, and the range and tendency toward activation in the vault room were examined. (60)Co and (152)Eu were identified by gamma-ray spectrometry of the concrete samples. (152)Eu and (60)Co are produced principally from the stable isotopes of europium and cobalt by neutron capture reactions. The radioactivity concentration did not vary much between the surface of the concrete and at a depth of 10 cm. Although the radioactivity concentration near the target was higher than the clearance level for radioactive waste indicated in IAEA RS-G-1.7, the mean radioactivity concentration in the walls and floor was lower than the clearance level. The radioactivity concentration of the inner concrete wall of the medical cyclotron vault room was not uniform. The areas exceeding the clearance level were in the vicinity of the target, but most of the building did not exceed the clearance levels.

  19. Stability of electrostatic ion cyclotron waves in a multi-ion plasma

    Indian Academy of Sciences (India)

    A detailed numerical study, for parameters relevant to comet Halley, shows that the growth rate is dependent on the magnitude of the frequency. The ion cyclotron waves are driven by the electron drift parallel to the magnetic field; the temperature anisotropy of the oxygen ions only slightly enhance the growth rates for small ...

  20. Tomsk Polytechnic University cyclotron as a source for neutron based cancer treatment.

    Science.gov (United States)

    Lisin, V A; Bogdanov, A V; Golovkov, V M; Musabaeva, L I; Sukhikh, L G; Verigin, D A

    2014-02-01

    In this paper we present our cyclotron based neutron source with average energy 6.3 MeV generated during the 13.6 MeV deuterons interactions with beryllium target, neutron field dosimetry, and dosimetry of attendant gamma fields. We also present application of our neutron source for cancer treatment.

  1. Measurements of injected beam deflections at the exit of a cyclotron inflector as a function of applied field or beam energy perturbations

    Energy Technology Data Exchange (ETDEWEB)

    Dehnel, M.P.; Erdman, K.L. [Ebco Technologies Inc., Richmond B.C. (Canada); Root, L.; Kuo, T. [TRIUMF, Vancouver B.C. (Canada)

    1999-07-01

    Measurements of the central trajectories of 25 keV H{sup -} beams at the exit of the EBCO/TRIUMF 1 MeV Test Cyclotron's spiral inflector have been made using quartz scintillators, a TV Camera, and image analysis equipment and software. Plots of the displacement of the central trajectories as a function of inflector electric potential, cyclotron magnetic field and beam injection energy changes are shown, and are compared to numerically computed data generated from an inflector design program. Details of the experimental methods, the hardware set-up and the results are reported. (author)

  2. A Proton-Cyclotron Wave Storm Generated by Unstable Proton Distribution Functions in the Solar Wind

    Science.gov (United States)

    Wicks, R. T.; Alexander, R. L.; Stevens, M.; Wilson, L. B., III; Moya, P. S.; Vinas, A.; Jian, L. K.; Roberts, D. A.; O’Modhrain, S.; Gilbert, J. A.; hide

    2016-01-01

    We use audification of 0.092 seconds cadence magnetometer data from the Wind spacecraft to identify waves with amplitudes greater than 0.1 nanoteslas near the ion gyrofrequency (approximately 0.1 hertz) with duration longer than 1 hour during 2008. We present one of the most common types of event for a case study and find it to be a proton-cyclotron wave storm, coinciding with highly radial magnetic field and a suprathermal proton beam close in density to the core distribution itself. Using linear Vlasov analysis, we conclude that the long-duration, large-amplitude waves are generated by the instability of the proton distribution function. The origin of the beam is unknown, but the radial field period is found in the trailing edge of a fast solar wind stream and resembles other events thought to be caused by magnetic field footpoint motion or interchange reconnection between coronal holes and closed field lines in the corona.

  3. A new, simple and precise method for measuring cyclotron proton beam energies using the activity vs. depth profile of zinc-65 in a thick target of stacked copper foils.

    Science.gov (United States)

    Asad, A H; Chan, S; Cryer, D; Burrage, J W; Siddiqui, S A; Price, R I

    2015-11-01

    The proton beam energy of an isochronous 18MeV cyclotron was determined using a novel version of the stacked copper-foils technique. This simple method used stacked foils of natural copper forming 'thick' targets to produce Zn radioisotopes by the well-documented (p,x) monitor-reactions. Primary beam energy was calculated using the (65)Zn activity vs. depth profile in the target, with the results obtained using (62)Zn and (63)Zn (as comparators) in close agreement. Results from separate measurements using foil thicknesses of 100, 75, 50 or 25µm to form the stacks also concurred closely. Energy was determined by iterative least-squares comparison of the normalized measured activity profile in a target-stack with the equivalent calculated normalized profile, using 'energy' as the regression variable. The technique exploits the uniqueness of the shape of the activity vs. depth profile of the monitor isotope in the target stack for a specified incident energy. The energy using (65)Zn activity profiles and 50-μm foils alone was 18.03±0.02 [SD] MeV (95%CI=17.98-18.08), and 18.06±0.12MeV (95%CI=18.02-18.10; NS) when combining results from all isotopes and foil thicknesses. When the beam energy was re-measured using (65)Zn and 50-μm foils only, following a major upgrade of the ion sources and nonmagnetic beam controls the results were 18.11±0.05MeV (95%CI=18.00-18.23; NS compared with 'before'). Since measurement of only one Zn monitor isotope is required to determine the normalized activity profile this indirect yet precise technique does not require a direct beam-current measurement or a gamma-spectroscopy efficiency calibrated with standard sources, though a characteristic photopeak must be identified. It has some advantages over published methods using the ratio of cross sections of monitor reactions, including the ability to determine energies across a broader range and without need for customized beam degraders. Copyright © 2015 Elsevier Ltd. All rights

  4. Modeling of electron cyclotron resonance acceleration in a stationary inhomogeneous magnetic field

    Directory of Open Access Journals (Sweden)

    Valeri D. Dougar-Jabon

    2008-04-01

    Full Text Available In this paper, the cyclotron autoresonance acceleration of electrons in a stationary inhomogeneous magnetic field is studied. The trajectory and energy of electrons are found through a numerical solution of the relativistic Newton-Lorentz equation by a finite difference method. The electrons move along a TE_{112} cylinder cavity in a steady-state magnetic field whose axis coincides with the cavity axis. The magnetic field profile is such that it keeps the phase difference between the electric microwave field and the electron velocity vector within the acceleration phase band. The microwaves amplitude of 6  kV/cm is used for numerical calculations. It is shown that an electron with an initial longitudinal energy of 8 keV can be accelerated up to 260 keV by 2.45 GHz microwaves at a distance of 17 cm.

  5. A Correlational Study of a Reading Comprehension Program and Attrition Rates of ESL Nursing Students in Texas

    Science.gov (United States)

    Donnell, Wendy

    2013-01-01

    Decreasing the attrition rate of nursing students has become an important issue for programs in Texas as a means to alleviate the nursing shortage (THECB, 2009). Programs are admitting a more diverse group of students but attrition has historically been high among minority groups (Gilchrist & Rector, 2007). The purpose of this study was to…

  6. A Correlational Study of a Reading Comprehension Program and Attrition Rates of ESL Nursing Students in Texas.

    Science.gov (United States)

    Donnell, Wendy M

    The purpose of this study was to examine the associations between English as a second language (ESL), a reading comprehension program, and attrition rates of nursing students. Higher attrition rates of ESL nursing students are an assumption, seemingly based on anecdotal evidence. Data reflecting ESL student attrition should be measured and analyzed so that students can be identified prior to attrition. A secondary analysis of a large database of 27 initial licensure programs in Texas was completed. Data analysis identified that ESL students who used a reading comprehension program were almost twice as likely to be off track or out of the program as ESL students who did not use the program. Nurse educators need to evaluate student profile characteristics in a comprehensive way when determining risk of attrition.

  7. Quasilinear diffusion coefficients in a finite Larmor radius expansion for ion cyclotron heated plasmas

    Science.gov (United States)

    Lee, Jungpyo; Wright, John; Bertelli, Nicola; Jaeger, Erwin F.; Valeo, Ernest; Harvey, Robert; Bonoli, Paul

    2017-05-01

    In this paper, a reduced model of quasilinear velocity diffusion by a small Larmor radius approximation is derived to couple the Maxwell's equations and the Fokker Planck equation self-consistently for the ion cyclotron range of frequency waves in a tokamak. The reduced model ensures the important properties of the full model by Kennel-Engelmann diffusion, such as diffusion directions, wave polarizations, and H-theorem. The kinetic energy change ( W ˙ ) is used to derive the reduced model diffusion coefficients for the fundamental damping (n = 1) and the second harmonic damping (n = 2) to the lowest order of the finite Larmor radius expansion. The quasilinear diffusion coefficients are implemented in a coupled code (TORIC-CQL3D) with the equivalent reduced model of the dielectric tensor. We also present the simulations of the ITER minority heating scenario, in which the reduced model is verified within the allowable errors from the full model results.

  8. Design of a correlation electron cyclotron emission diagnostic for Alcator C-Moda)

    Science.gov (United States)

    Sung, C.; White, A. E.; Irby, J. H.; Leccacorvi, R.; Vieira, R.; Oi, C. Y.; Peebles, W. A.; Nguyen, X.

    2012-10-01

    A correlation electron cyclotron emission (CECE) diagnostic has been installed in Alcator C-Mod. In order to measure electron temperature fluctuations, this diagnostic uses a spectral decorrelation technique. Constraints obtained with nonlinear gyrokinetic simulations guided the design of the optical system and receiver. The CECE diagnostic is designed to measure temperature fluctuations which have kθ ≤ 4.8 cm-1 (kθρs < 0.5) using a well-focused beam pattern. Because the CECE diagnostic is a dedicated turbulence diagnostic, the optical system is also flexible, which allows for various collimating lenses and antenna to be used. The system overview and the demonstration of its operability as designed are presented in this paper.

  9. Assessing aquifer storage and recovery feasibility in the Gulf Coastal Plains of Texas

    OpenAIRE

    W. Benjamin Smith; Gretchen R. Miller; Zhuping Sheng

    2017-01-01

    Study region: The Gulf Coast and Carrizo-Wilcox aquifer systems in the Gulf Coastal Plains of Texas. Study focus: Aquifer storage and recovery is a water storage alternative that is underutilized in Texas, a state with both long periods of drought and high intensity storms. Future water storage plans in Texas almost exclusively rely on surface reservoirs, subject to high evaporative losses. This study seeks to identify sites where aquifer storage and recovery (ASR) may be successful, especial...

  10. Adaptive-array Electron Cyclotron Emission diagnostics using data streaming in a Software Defined Radio system

    Science.gov (United States)

    Idei, H.; Mishra, K.; Yamamoto, M. K.; Hamasaki, M.; Fujisawa, A.; Nagashima, Y.; Hayashi, Y.; Onchi, T.; Hanada, K.; Zushi, H.; the QUEST Team

    2016-04-01

    Measurement of the Electron Cyclotron Emission (ECE) spectrum is one of the most popular electron temperature diagnostics in nuclear fusion plasma research. A 2-dimensional ECE imaging system was developed with an adaptive-array approach. A radio-frequency (RF) heterodyne detection system with Software Defined Radio (SDR) devices and a phased-array receiver antenna was used to measure the phase and amplitude of the ECE wave. The SDR heterodyne system could continuously measure the phase and amplitude with sufficient accuracy and time resolution while the previous digitizer system could only acquire data at specific times. Robust streaming phase measurements for adaptive-arrayed continuous ECE diagnostics were demonstrated using Fast Fourier Transform (FFT) analysis with the SDR system. The emission field pattern was reconstructed using adaptive-array analysis. The reconstructed profiles were discussed using profiles calculated from coherent single-frequency radiation from the phase array antenna.

  11. Texas LPG fuel cell development and demonstration project

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2004-07-26

    The State Energy Conservation Office has executed its first Fuel Cell Project which was awarded under a Department of Energy competitive grant process. The Texas LPG Fuel Processor Development and Fuel Cell Demonstration Program is a broad-based public/private partnership led by the Texas State Energy Conservation Office (SECO). Partners include the Alternative Fuels Research and Education Division (AFRED) of the Railroad Commission of Texas; Plug Power, Inc., Latham, NY, UOP/HyRadix, Des Plaines, IL; Southwest Research Institute (SwRI), San Antonio, TX; the Texas Natural Resource Conservation Commission (TNRCC), and the Texas Department of Transportation (TxDOT). The team proposes to mount a development and demonstration program to field-test and evaluate markets for HyRadix's LPG fuel processor system integrated into Plug Power's residential-scale GenSys(TM) 5C (5 kW) PEM fuel cell system in a variety of building types and conditions of service. The program's primary goal is to develop, test, and install a prototype propane-fueled residential fuel cell power system supplied by Plug Power and HyRadix in Texas. The propane industry is currently funding development of an optimized propane fuel processor by project partner UOP/HyRadix through its national checkoff program, the Propane Education and Research Council (PERC). Following integration and independent verification of performance by Southwest Research Institute, Plug Power and HyRadix will produce a production-ready prototype unit for use in a field demonstration. The demonstration unit produced during this task will be delivered and installed at the Texas Department of Transportation's TransGuide headquarters in San Antonio, Texas. Simultaneously, the team will undertake a market study aimed at identifying and quantifying early-entry customers, technical and regulatory requirements, and other challenges and opportunities that need to be addressed in planning commercialization of the units

  12. 75 FR 55978 - Approval and Promulgation of Air Quality Implementation Plans; Texas; Revisions to the New Source...

    Science.gov (United States)

    2010-09-15

    ... Chemical Council (TCC); Texas Commission on Environmental Quality (TCEQ); Members of the Texas House of..., ERCC, GCLC and TCC commented that Texas submitted a revision to 30 TAC 116.160(a) and a new section 116... corrected the deficiencies identified in the proposal. Comment 7: BCCA, TIP, ERCC, and TCC commented that...

  13. Electron cyclotron emission imaging diagnostic system for Rijnhuizen Tokamak Project

    NARCIS (Netherlands)

    Deng, B.H.; Hsia, R. P.; Domier, C.W.; Burns, S. R.; Hillyer, T. R.; N C Luhmann Jr.,; Oyevaar, T.; Donne, A. J. H.; R. T. P. Team,

    1999-01-01

    A 16-channel electron cyclotron emission (ECE) imaging diagnostic system has been developed and installed on the Rijnhuizen Tokamak Project for measuring plasma electron cyclotron emission with a temporal resolution of 2 mu s. The high spatial resolution of the system is achieved by utilizing a low

  14. Development of a system for passive spectrometry characterization neutron of a cyclotron; Desarrollo de un sistema de espectrometria pasivo para la caracterizacion neutronica de un ciclotron

    Energy Technology Data Exchange (ETDEWEB)

    Mendez, R.; Guerrero, J. E.; Lagares, J. I.; Sansaloni, F.; Perez, J. M.; Llop, J.; Kralik, M.

    2013-07-01

    The most widely used for Neutron spectrometry system is formed by the Bonner spheres with an active sensor sensitive to thermal neutrons in its Center. But, the presence of strong electromagnetic fields and the hold character around a cyclotron radiation detectors active employment make unviable so it is necessary to replace it with other liabilities. In this case it has resorted to the use of Au foils such as thermal neutron detectors, found the matrix the new spectrometer response and has been validated with a source of {sup 2}52Cf for later measurements in the interior of the bunker of a cyclotron production of radioisotopes for PET. (Author)

  15. Environmental Education Organizations and Programs in Texas: Identifying Patterns through a Database and Survey Approach for Establishing Frameworks for Assessment and Progress

    Science.gov (United States)

    Lloyd-Strovas, Jenny D.; Arsuffi, Thomas L.

    2016-01-01

    We examined the diversity of environmental education (EE) in Texas, USA, by developing a framework to assess EE organizations and programs at a large scale: the Environmental Education Database of Organizations and Programs (EEDOP). This framework consisted of the following characteristics: organization/visitor demographics, pedagogy/curriculum,…

  16. A Study of the Aquaculture Industry in Texas to Assist in Establishing Aquaculture as a Course Offering in Agricultural Science and Technology. Final Report.

    Science.gov (United States)

    Dillingham, John; And Others

    A 1989-90 project determined the knowledge and skills necessary for employment in the aquaculture industry. The study identified technical materials and other resources available in private industry and higher education institutions. Two surveys determined the status of aquaculture in Texas school districts and identified tasks performed by…

  17. Energy Policy Case Study - Texas: Wind, Markets, and Grid Modernization

    Energy Technology Data Exchange (ETDEWEB)

    Orrell, Alice C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Homer, Juliet S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bender, Sadie R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Weimar, Mark R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-09-19

    This document presents a case study of energy policies in Texas related to power system transformation, renewable energy and distributed energy resources (DERs). Texas has experienced a dramatic increase in installed wind capacity, from 116 MW in 2000 to over 15,000 MW in 2015. This achievement was enabled by the designation of Competitive Renewable Energy Zones (CREZs) and new transmission lines that transmit wind to load centers. This report highlights nascent efforts to include DERs in the ERCOT market. As costs decline and adoption rates increase, ERCOT expects distributed generation to have an increasing effect on grid operations, while bringing potentially valuable new resources to the wholesale markets.

  18. Anomalous cyclotron mass dependence on the magnetic field and Berry’s phase in (Cd1-x-y Zn x Mn y )3As2 solid solutions

    Science.gov (United States)

    Zakhvalinskii, V. S.; Nikulicheva, T. B.; Lähderanta, E.; Shakhov, M. A.; Nikitovskaya, E. A.; Taran, S. V.

    2017-11-01

    Shubnikov-de Haas (SdH) effect and magnetoresistance measurements of single crystals of diluted II-V magnetic semiconductors (Cd1-x-y Zn x Mn y )3As2 (x  +  y  =  0.4, y  =  0.04 and 0.08) are investigated in the temperature range T  =  4.2 ÷ 300 K and in transverse magnetic field B  =  0 ÷ 25 T. The values of the cyclotron mass m c, the effective g-factor g*, and the Dingle temperature T D are defined. In one of the samples (y  =  0.04) a strong dependence of the cyclotron mass on the magnetic field m c(B)  =  m c(0)  +  αB is observed. The value of a phase shift close to β  =  0.5 indicates the presence of Berry phase and 3D Dirac fermions in a single crystals of (Cd1-x-y Zn x Mn y )3As2 in one of the samples (y  =  0.08).

  19. Latest Guadalupian (Middle Permian) conodonts and foraminifers from West Texas

    Science.gov (United States)

    Lambert, L.L.; Wardlaw, B.R.; Nestell, M.K.; Nestell, G.P.

    2002-01-01

    Clarkina, which characterizes Upper Permian (Lopingian Series) strata, evolved from Jinogondolella altudaensis in the Delaware basin of West Texas as demonstrated by transitional continuity. The West Texas section is significantly more complete in the uppermost Guadalupian interval than that of the probable GSSP reference section in South China, and clarifies the phylogenetic relationships among other conodont taxa as well. Jinogondolella granti clearly evolved into J. artafrons new species, both characterized by Pa elements with a distinctive fused carina. Representatives of Jinogondolella crofti are limited to the uppermost part of the altudaensis zone, and are interpreted as terminal paedomorphs. The associated foraminifer (non-fusulinid) fauna has some species in common with Zechstein faunas, possibly presaging the evaporitic basin that would develop following this latest Guadalupian marine deposition in West Texas.

  20. Stabilization of ion fishbone activities by electron cyclotron resonance heating in a toroidal plasma

    Science.gov (United States)

    Chen, W.; Yu, L. M.; Shi, P. W.; Ma, R.; Ji, X. Q.; Jiang, M.; Zhu, X. L.; Shi, Z. B.; Yu, D. L.; Yuan, B. S.; Li, Y. G.; Yang, Z. C.; Cao, J. Y.; Song, S. D.; Zhong, W. L.; He, H. D.; Dong, J. Q.; Ding, X. T.; Yan, L. W.; Liu, Yi.; Yang, Q. W.; Xu, M.; Duan, X. R.

    2018-01-01

    We report an experimental result on the stabilization of the energetic–ion driven internal kink mode (ion fishbone) by electron cyclotron resonance heating (ECRH), observed for the first time in a toroidal plasma. The mode asserts itself a resistive branch close to the marginal stability point. The resulting fishbone mode depends not only on the injected power but also on the radial deposition location of ECRH, and the instability can be completely suppressed when the injected ECRH power exceeds certain threshold. Analysis by the fishbone dispersion relation, including the resistive effect, suggests that the magnetic Reynolds number plays a key role in the mode stabilization—it weakens the mode growth-rate and enhances the critical energetic–ion beta without changing the energetic–ion population. This ion fishbone stabilization mechanism can be important for future devices such as ITER, which has significant ECRH capability.

  1. A relativistic model of electron cyclotron current drive efficiency in tokamak plasmas

    Directory of Open Access Journals (Sweden)

    Lin-Liu Y.R.

    2012-09-01

    Full Text Available A fully relativistic model of electron cyclotron current drive (ECCD efficiency based on the adjoint function techniques is considered. Numerical calculations of the current drive efficiency in a tokamak by using the variational approach are performed. A fully relativistic extension of the variational principle with the modified basis functions for the Spitzer function with momentum conservation in the electron-electron collision is described in general tokamak geometry. The model developed has generalized that of Marushchenko’s (N.B . Marushchenko, et al. Fusion Sci. & Tech., 2009, which is extended for arbitrary temperatures and covers exactly the asymptotic for u ≫ 1 when Z → ∞, and suitable for ray-tracing calculations.

  2. Studies for the ion cyclotron range of frequency heating in a tokamak fusion experimental device

    Energy Technology Data Exchange (ETDEWEB)

    Saigusa, Mikio [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment

    1996-02-01

    Ion cyclotron range of frequency heating has been investigated as an efficient additional plasma heating and non-inductive current driving methods in a tokamak type fusion experimental device. At first, an ICRF antenna coupling code was developed for the estimation of the coupling properties of phased antenna array, so that the ICRF antennas were designed for JT-60 and JT-60U ICRF heating systems using the coupling codes. The ICRF heating experiments had been performed in JT-60 and JT-60U. The coupling properties of ICRF antenna, the physics of peripheral plasma and energy confinement by ICRF heating in various heating regimes have been investigated. Next, the Toroidicity induced Alfven Eigen (TAE) mode have been studied using minority ICRF heating for producing energetic ions which can excite TAE mode. The TAE mode could be suppressed by current profile control using current ramp operation and lower hybrid current drive. (author) 74 refs.

  3. Ion Bernstein instability as a possible source for oxygen ion cyclotron harmonic waves

    Science.gov (United States)

    Min, Kyungguk; Denton, Richard E.; Liu, Kaijun; Gary, S. Peter; Spence, Harlan E.

    2017-05-01

    This paper demonstrates that an ion Bernstein instability can be a possible source for recently reported electromagnetic waves with frequencies at or near the singly ionized oxygen ion cyclotron frequency, ΩO+, and its harmonics. The particle measurements during strong wave activity revealed a relatively high concentration of oxygen ions (˜15%) whose phase space density exhibits a local peak at energy ˜20 keV. Given that the electron plasma-to-cyclotron frequency ratio is ωpe/Ωe≳1, this energy corresponds to the particle speed v/vA≳0.3, where vA is the oxygen Alfvén speed. Using the observational key plasma parameters, a simplified ion velocity distribution is constructed, where the local peak in the oxygen ion velocity distribution is represented by an isotropic shell distribution. Kinetic linear dispersion theory then predicts unstable Bernstein modes at or near the harmonics of ΩO+ and at propagation quasi-perpendicular to the background magnetic field, B0. If the cold ions are mostly protons, these unstable modes are characterized by a low compressibility (|δB∥|2/|δB|2≲0.01), a small phase speed (vph˜0.2vA), a relatively small ratio of the electric field energy to the magnetic field energy (between 10-4 and 10-3), and the Poynting vector directed almost parallel to B0. These linear properties are overall in good agreement with the properties of the observed waves. We demonstrate that superposition of the predicted unstable Bernstein modes at quasi-perpendicular propagation can produce the observed polarization properties, including the minimum variance direction on average almost parallel to B0.

  4. Cyclotron Lines: From Magnetic Field Strength Estimators to ...

    Indian Academy of Sciences (India)

    Chandreyee Maitra

    2017-09-12

    Sep 12, 2017 ... With forty years since the discovery of the first cyclotron line in Her X-1, there have been remarkable ... the important results related to cyclotron lines since its discovery and reviews their significance. ... context can provide, to build a complete picture for the physics of accretion and hence X-ray emission in.

  5. Diabetes prevalence and treatment adherence in residents living in a colonia located on the West Texas, USA/Mexico border.

    Science.gov (United States)

    Anders, Robert L; Olson, Thomas; Wiebe, John; Bean, Nathaniel H; DiGregorio, Rena; Guillermina, Mina; Ortiz, Melchor

    2008-09-01

    Little is known about how diabetes affects the health status of Hispanic people living in colonias located along the USA/Mexico border. The purpose of this report is to describe the demographic factors, prevalence of diabetes, and the health status of the residents living in a colonia on the border between El Paso, Texas, USA, and Juarez, Mexico, and to report the residents' adherence to the Behavioral Risk Factor Surveillance System (BRFSS) protocols for the management of type 2 diabetes. This study included 188 participants. The instruments used included a demographic questionnaire, the Short Acculturation Scale for Hispanics, "Cutting Down, Annoyance by Criticism, Guilty Feelings, and Eye-openers", BRFSS, and the Short Form-36 (v2). The prevalence of diabetes was 15.4% and 41.3% of the residents had a Body Mass Index score > 30. The rate of hypertension, elevated cholesterol, and depression for those reporting diabetes was significant. The SF-36 v2 physical score for the diabetic residents was 42.9 and it was 52.4 for the non-diabetic residents. The average resident of the colonia who reports diabetes has many health disadvantages when compared to those in other parts of Texas and the USA generally.

  6. Influence of electron injection on electron cyclotron resonance plasma properties and reflected mode electrons (abstract)

    Science.gov (United States)

    Ovsyannikov, V. P.; Ullmann, F.; Zschornack, G.

    2000-02-01

    The injection of an additional strong focused electron beam from a special designed electron gun into a magnetic electron cyclotron resonance (ECR) confinement field is studied. The electron gun uses a cathode with a long lifetime and resistiveness providing high emission current densities with electron currents up to 50 mA and voltages up to 4 keV. A sequence of aluminum foils is used to investigate the trajectories of the electrons in the magnetic field without plasma. The high density electron beam passes through the foils, welds them, and prints its image into the foils. Details of this technique are described in Ref. 1. Using this technique we see that before the electrons enter the sextupole region the beam moves along the magnetic straight lines preserving its structure. Only a central beam passes through the sextupole region, thereby changing its form due to the interaction with radial components of the magnetic field. A new operation method at our 14.5 GHz ECR ion source is based on so-called reflection mode electrons (RMEs) analogous to a known electron beam ion source operation regime.2 The basic idea is that electrons, which traveling from the cathode in a strong axial field, meet an anticathode potential, are reflected from it, move back to the cathode, and will be reflected again and so on. It can be supposed that the electrons will make reflections up to the moment when the anode aperture of the gun is fulfilled and the electrons will be collected on the anode electrode. Investigations are performed extracting nitrogen ions using the RME beam. As a result we got a clear increase in the beam current of the extracted ions (e.g., at 10 mA electron injection an increase of the current of N5+ ions up to 400%) and a shift of the measured ion charge state distribution to higher mean ionization stages. Measured x-ray spectra from a neon loaded plasma show for the case of RME operation increasing energy shifts to the high energy side of the spectra, i.e., the

  7. Identifying Potential Conflict Associated with Oil and Gas Exploration in Texas State Coastal Waters: A Multicriteria Spatial Analysis

    Science.gov (United States)

    Brody, Samuel D.; Grover, Himanshu; Bernhardt, Sarah; Tang, Zhenghong; Whitaker, Bianca; Spence, Colin

    2006-10-01

    Recent interest in expanding offshore oil production within waters of the United States has been met with opposition by groups concerned with recreational, environmental, and aesthetic values associated with the coastal zone. Although the proposition of new oil platforms off the coast has generated conflict over how coastal resources should be utilized, little research has been conducted on where these user conflicts might be most intense and which sites might be most suitable for locating oil production facilities in light of the multiple, and often times, competing interests. In this article, we develop a multiple-criteria spatial decision support tool that identifies the potential degree of conflict associated with oil and gas production activities for existing lease tracts in the coastal margin of Texas. We use geographic information systems to measure and map a range of potentially competing representative values impacted by establishing energy extraction infrastructure and then spatially identify which leased tracts are the least contentious sites for oil and gas production in Texas state waters. Visual and statistical results indicate that oil and gas lease blocks within the study area vary in their potential to generate conflict among multiple stakeholders.

  8. Incidence and risk factors for hepatocellular carcinoma in Texas Latinos: implications for prevention research.

    Directory of Open Access Journals (Sweden)

    Amelie G Ramirez

    Full Text Available Hepatocellular carcinoma (HCC is increasing in the U.S. despite a decline in cancer overall. Latinos have higher rates of HCC than the general population according to the Surveillance, Epidemiology, and End Results (SEER Program. Not included in SEER, Texas Latinos make up one-fifth of the U.S. Latino population. To determine whether HCC incidence differs among U.S. and Texas Latinos, this descriptive study compares HCC incidence from 1995 through 2006 among three Latino populations: U.S. SEER, Texas overall and a South Texas subset. To identify lines of prevention research, we compare prevalence of known HCC risk factors among these Latino groups.Data were collected from the U.S. SEER Program, Texas Cancer Registry and Texas Department of State Health Services (TDSHS. Annual age-specific and age-adjusted HCC incidence rates, annual percent changes (APCs and 95% confidence intervals were calculated as well as prevalence of obesity, diabetes, heavy alcohol use and cigarette smoking.Of the three Latino groups compared, South Texas Latinos had the highest age-adjusted HCC incidence rates and SEER Latinos had the lowest (10.6/100,000 (10.1-11.1 and 7.5/100,000 (7.2-7.7, respectively. HCC incidence significantly increased over time (APCs>0 among Latinos in all three geographic groups. Between 1995 and 2006, there was an increase in obesity among all three populations, and obesity was highest among South Texas Latinos. Diabetes increased among U.S. Latinos, and Latino women in South Texas had significantly higher diabetes prevalence than U.S. Latino women. Cigarette smoking and heavy alcohol use were similar among groups.The incidence of HCC among Latinos in South Texas is higher than elsewhere in the United States. Higher rates of HCC among Texas and South Texas Latinos may be associated with greater prevalence of obesity and diabetes, risk factors for HCC that are amenable to intervention.

  9. Diet- and Body Size-Related Attitudes and Behaviors Associated with Vitamin Supplement Use in a Representative Sample of Fourth-Grade Students in Texas

    Science.gov (United States)

    George, Goldy C.; Hoelscher, Deanna M.; Nicklas, Theresa A.; Kelder, Steven H.

    2009-01-01

    Objective: To examine diet- and body size-related attitudes and behaviors associated with supplement use in a representative sample of fourth-grade students in Texas. Design: Cross-sectional data from the School Physical Activity and Nutrition study, a probability-based sample of schoolchildren. Children completed a questionnaire that assessed…

  10. The association between sensation seeking and e-cigarette use in Texas young adults: A cross-sectional study.

    Science.gov (United States)

    Case, Kathleen R; Loukas, Alexandra; Harrell, Melissa B; Wilkinson, Anna V; Springer, Andrew E; Pérez, Adriana; Creamer, MeLisa R; Perry, Cheryl L

    2017-01-01

    To examine the associations between sensation seeking and ever and current e-cigarette use in Texas young adults (18-29 years old). Current cigarette use was examined as a potential effect modifier of the associations. Participants included college students enrolled in four-year and two-year colleges in four metropolitan areas in Texas (n  =  5,418) who completed the survey between November 2014 and February 2015. This cross-sectional study utilized mixed effects logistic regression to determine the associations between mean sensation seeking scores and ever and current e-cigarette use after controlling for covariates. After controlling for covariates, significant associations between sensation seeking and both ever and current e-cigarette use were observed; however, these associations were significant for noncurrent smokers only (adjusted odds rations [AOR]  =  1.55, 95% confidence interval (CI)  =  1.39, 1.73; AOR  =  1.82, 95% CI  =  1.54, 2.15, respectively). Sensation seeking is an important factor in identifying college students who may be at increased risk for e-cigarette use behaviors.

  11. The mitochondrial genome of a Texas outbreak strain of the cattle tick, Rhipicephalus (Boophilus) microplus, derived from whole genome sequencing Pacific Biosciences and Illumina reads.

    Science.gov (United States)

    McCooke, John K; Guerrero, Felix D; Barrero, Roberto A; Black, Michael; Hunter, Adam; Bell, Callum; Schilkey, Faye; Miller, Robert J; Bellgard, Matthew I

    2015-10-15

    The cattle fever tick, Rhipicephalus (Boophilus) microplus is one of the most significant medical veterinary pests in the world, vectoring several serious livestock diseases negatively impacting agricultural economies of tropical and subtropical countries around the world. In our study, we assembled the complete R. microplus mitochondrial genome from Illumina and Pac Bio sequencing reads obtained from the ongoing R. microplus (Deutsch strain from Texas, USA) genome sequencing project. We compared the Deutsch strain mitogenome to the mitogenome from a Brazilian R. microplus and from an Australian cattle tick that has recently been taxonomically designated as Rhipicephalus australis after previously being considered R. microplus. The sequence divergence of the Texas and Australia ticks is much higher than the divergence between the Texas and Brazil ticks. This is consistent with the idea that the Australian ticks are distinct from the R. microplus of the Americas. Published by Elsevier B.V.

  12. 77 FR 71344 - Texas: Final Authorization of State-initiated Changes and Incorporation by Reference of State...

    Science.gov (United States)

    2012-11-30

    ... pollution control, Water supply. Authority: This rule is issued under the authority of Sections 2002(a...) Texas Water Code (TWC), Texas Codes Annotated, as amended effective September 1, 2009: Chapter 5... AGENCY 40 CFR Parts 271 and 272 Texas: Final Authorization of State-initiated Changes and Incorporation...

  13. 76 FR 71260 - Approval and Promulgation of Implementation Plans; Texas; Revisions to the New Source Review (NSR...

    Science.gov (United States)

    2011-11-17

    ... permitting under Title 30 of the Texas Administrative Code (30 TAC), Chapter 116--Control of Air Pollution by...: Our Land, Our Lives; Texas Protecting Our Land, Water, and Environment; Citizens for a Clean... AGENCY 40 CFR Part 52 Approval and Promulgation of Implementation Plans; Texas; Revisions to the New...

  14. PRODUCTION OF 11 C-METHIONINE BY CYCLOTRON AVF JAERI

    Directory of Open Access Journals (Sweden)

    Sri Hastini

    2010-06-01

    Full Text Available At the Takasaki-site of JAERI, an AVF cyclotron has been constructed for advanced radiation technology research. The cyclotron produces extracted beams particularly light and heavy ions of proton as well as deutron. Target chamber is available for production of 11CO2 a positron emitter radioisotope, by bombardment of proton from nitrogen gas as a target, by 14 N (p,a 11C reaction. The use of incident energy on target was estimated to be 11 MeV for primary proton energy of 20 MeV and the beam current was 0,1 m A and the irradiation time was 10 minutes for production of 11CO2 and the yield was about 30 MBq (EOBand for irradiation time 15 minutes and the beam current was 1 mA for production of 11C-Methionine, the yield was about 70 MBq (EOB. Remotely operated automatic and semiautomatic processing systems are used for the production of the 11 C-Methionine agent and the radiochemical purity of the product obtained was determined by High Performance Liquid Chromatography (HPLC with cation exchange column was LC 10 AD MERCK LICHROSPHER 100 RP-18 and the mobile phase was 10 mM ammonium phormmate, the mean of retention time was 1,815 minutes and the radiochemical purity to be more than 90 %. The product was used for plant studies and visualized by PETIS (Positron Emission Tracer Imaging System   Keywords: cyclotron, Positron emitter, 11C-Methionine.

  15. Demographic and Spatial Characteristics of Feral Hogs in the Chihuahuan Desert, Texas

    OpenAIRE

    Adkins, Roger N.; Harveson, Louis A.

    2007-01-01

    Feral hogs (Sus scrofa) have recently expanded their range to include portions of the arid regions of the Chihuahuan Desert, Texas. We examined feral hog density, survival rates, range size, and habitat use in the Davis Mountains, Texas, to understand hog ecology in a desert environment. We tested the hypothesis that densities of feral hogs across Texas would be positively related to precipitation. Feral hog densities in the Chihuahuan Desert were low (0.65 individuals/km2), supporting our pr...

  16. A survey by Texas A & M University to characterize the principal components of benthic communities over the entire northern Gulf of Mexico, 1999 - 2002 (NODC Accession 0002193)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A research program has been initiated by the Minerals Management Service (Contract No. 1435-01-99-CT-30991) to gain better knowledge of the benthic communities of...

  17. A survey by Texas A & M University to characterize the principal components of benthic communities over the entire northern Gulf of Mexico, 1999 - 2002 (NODC Accession 0002295)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A research program has been initiated by the Minerals Management Service (Contract No. 1435-01-99-CT-30991)to gain better knowledge of the benthic communities of the...

  18. The Status of School Finance Equity in Texas: A 2009 Update

    Science.gov (United States)

    Cortez, Albert

    2009-01-01

    In Texas, all students are equal, but once again some are more equal than others. This policy update provides a description of the key elements of the existing Texas school funding system, identifies features that contribute to equity and those that maintain and expand inequity, and includes recommended reforms that would reinstate critical…

  19. A Qualitative Case Study of the Bilingual Teacher Shortage in One Texas School District

    Science.gov (United States)

    Kennedy, Barbara H.

    2013-01-01

    The purpose of this study was to examine how stakeholders in one Texas school district perceive, experience, and respond to the Spanish bilingual teacher shortage. The research design was qualitative with an exploratory, single case study approach. The case study school district was a mid-sized suburban district in Texas that utilized a dual…

  20. 75 FR 56423 - Approval and Promulgation of Implementation Plans; Texas; Revisions to the New Source Review (NSR...

    Science.gov (United States)

    2010-09-15

    ... Chemical Council (TCC); Texas Commission on Environmental Quality (TCEQ); Texas Association Business... 116.150(d). Response: See response to Comment 1. Comment 3: BCCA, TIP, TCC, commented that the Texas... CAA Sec. 172(e) and not a basis for disapproval of the proposed SIP revision. TCC stated that it is...

  1. Life-Cycle Cost Study for a Low-Level Radioactive Waste Disposal Facility in Texas

    Energy Technology Data Exchange (ETDEWEB)

    B. C. Rogers; P. L. Walter (Rogers and Associates Engineering Corporation); R. D. Baird

    1999-08-01

    This report documents the life-cycle cost estimates for a proposed low-level radioactive waste disposal facility near Sierra Blanca, Texas. The work was requested by the Texas Low-Level Radioactive Waste Disposal Authority and performed by the National Low-Level Waste Management Program with the assistance of Rogers and Associates Engineering Corporation.

  2. A new genus of wolf spiders from Mexico and Southern United States, with description of a new species from Texas (Araneae: Lycosidae Género nuevo de arañas lobo de México y sur de Estados Unidos, y descripción de una especie nueva de Texas (Araneae: Lycosidae

    Directory of Open Access Journals (Sweden)

    Charles D Dondale

    2005-06-01

    Full Text Available Pardosa parallela Banks, 1898 is made the type species of the new genus Camptocosa. Camptocosa parallela new combination is re-described from fresh material, and a new species C. texana, is described from Texas.Pardosa parallela Banks, 1898 ha sido designada como especie tipo del nuevo género Camptocosa. Camptocosa parallela nueva combinación, es redescrita de material recientemente colectado y una nueva especie, C. texana es descrita para Texas.

  3. Ion cyclotron resonance cell

    Science.gov (United States)

    Weller, R.R.

    1995-02-14

    An ion cyclotron resonance cell is disclosed having two adjacent sections separated by a center trapping plate. The first section is defined by the center trapping plate, a first end trapping plate, and excitation and detector electrodes. The second section includes a second end trapping plate spaced apart from the center plate, a mirror, and an analyzer. The analyzer includes a wavelength-selective light detector, such as a detector incorporating an acousto-optical device (AOD) and a photodetector. One or more ion guides, grounded plates with holes for the ion beam, are positioned within the vacuum chamber of the mass spectrometer between the ion source and the cell. After ions are trapped and analyzed by ion cyclotron resonance techniques in the first section, the ions of interest are selected according to their mass and passed into the second section for optical spectroscopic studies. The trapped ions are excited by light from a laser and caused thereby to fluoresce. The fluorescent light emitted by the excited ions is reflected by the mirror and directed onto the detector. The AOD is scanned, and the photodetector output is recorded and analyzed. The ions remain in the second section for an extended period, enabling multiple studies to be carried out on the same ensemble of ions. 5 figs.

  4. Soil response to clearcutting and site preparation in East Texas

    Science.gov (United States)

    John J. Stransky; Lowell K. Halls; K.G. Watterston

    1982-01-01

    On an east Texas forest site, clearcutting and site preparation did not change the soil pH. Chopping and KG blading significantly reduced organic matter i n the surface soil, while burning slightly increased it. Organic matter showed a positive and significant relationship to potassium, calcium and magnesium. Allsite treatments increased phosphorus and potassium, with...

  5. Decline of red-eared sliders (Trachemys scripta elegans) and Texas spiny softshells (Apalone spinifera emoryi) in the Lower Rio Grande Valley of Texas

    Science.gov (United States)

    Donald J. Brown; Amanda D. Schultz; James R. Dixon; Brian E. Dickerson; Michael R. J. Forstner

    2012-01-01

    In 2009, we repeated a freshwater turtle survey first conducted in 1976 in the Lower Rio Grande Valley (LRGV) of Texas to determine whether the abundance of freshwater turtles in the LRGV has changed over the past three decades. We captured significantly fewer red-eared sliders (Trachemys scripta elegans) and Texas spiny softshells (Apalone spinifera emoryi) in 2...

  6. Data collection and compilation for a geodatabase of groundwater, surface-water, water-quality, geophysical, and geologic data, Pecos County Region, Texas, 1930-2011

    Science.gov (United States)

    Pearson, Daniel K.; Bumgarner, Johnathan R.; Houston, Natalie A.; Stanton, Gregory P.; Teeple, Andrew; Thomas, Jonathan V.

    2012-01-01

    The U.S. Geological Survey, in cooperation with Middle Pecos Groundwater Conservation District, Pecos County, City of Fort Stockton, Brewster County, and Pecos County Water Control and Improvement District No. 1, compiled groundwater, surface-water, water-quality, geophysical, and geologic data for site locations in the Pecos County region, Texas, and developed a geodatabase to facilitate use of this information. Data were compiled for an approximately 4,700 square mile area of the Pecos County region, Texas. The geodatabase contains data from 8,242 sampling locations; it was designed to organize and store field-collected geochemical and geophysical data, as well as digital database resources from the U.S. Geological Survey, Middle Pecos Groundwater Conservation District, Texas Water Development Board, Texas Commission on Environmental Quality,and numerous other State and local databases. The geodatabase combines these disparate database resources into a simple data model. Site locations are geospatially enabled and stored in a geodatabase feature class for cartographic visualization and spatial analysis within a Geographic Information System. The sampling locations are related to hydrogeologic information through the use of geodatabase relationship classes. The geodatabase relationship classes provide the ability to perform complex spatial and data-driven queries to explore data stored in the geodatabase.

  7. A mode converter to generate a Gaussian-like mode for injection into the VENUS electron cyclotron resonance ion source

    Energy Technology Data Exchange (ETDEWEB)

    Lyneis, C., E-mail: CMLyneis@lbl.gov; Benitez, J.; Hodgkinson, A.; Strohmeier, M.; Todd, D. [Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Plaum, B. [Institut für Grenzflächenverfahrenstechnik und Plasmatechnologie (IGVP), Stuttgart (Germany); Thuillier, T. [Laboratoire de Physique Subatomique et de Cosmologie, Université Joseph Fourier Grenoble 1, CNRS/IN2P3, Institut Polytechnique de Grenoble, 53 rue des martyrs 38026 Grenoble cedex (France)

    2014-02-15

    A number of superconducting electron cyclotron resonance (ECR) ion sources use gyrotrons at either 24 or 28 GHz for ECR heating. In these systems, the microwave power is launched into the plasma using the TE{sub 01} circular waveguide mode. This is fundamentally different and may be less efficient than the typical rectangular, linearly polarized TE{sub 10} mode used for launching waves at lower frequencies. To improve the 28 GHz microwave coupling in VENUS, a TE{sub 01}-HE{sub 11} mode conversion system has been built to test launching HE{sub 11} microwave power into the plasma chamber. The HE{sub 11} mode is a quasi-Gaussian, linearly polarized mode, which should couple strongly to the plasma electrons. The mode conversion is done in two steps. First, a 0.66 m long “snake” converts the TE{sub 01} mode to the TE{sub 11} mode. Second, a corrugated circular waveguide excites the HE{sub 11} mode, which is launched directly into the plasma chamber. The design concept draws on the development of similar devices used in tokamaks and stellerators. The first tests of the new coupling system are described below.

  8. A mode converter to generate a Gaussian-like mode for injection into the VENUS electron cyclotron resonance ion source.

    Science.gov (United States)

    Lyneis, C; Benitez, J; Hodgkinson, A; Plaum, B; Strohmeier, M; Thuillier, T; Todd, D

    2014-02-01

    A number of superconducting electron cyclotron resonance (ECR) ion sources use gyrotrons at either 24 or 28 GHz for ECR heating. In these systems, the microwave power is launched into the plasma using the TE01 circular waveguide mode. This is fundamentally different and may be less efficient than the typical rectangular, linearly polarized TE10 mode used for launching waves at lower frequencies. To improve the 28 GHz microwave coupling in VENUS, a TE01-HE11 mode conversion system has been built to test launching HE11 microwave power into the plasma chamber. The HE11 mode is a quasi-Gaussian, linearly polarized mode, which should couple strongly to the plasma electrons. The mode conversion is done in two steps. First, a 0.66 m long "snake" converts the TE01 mode to the TE11 mode. Second, a corrugated circular waveguide excites the HE11 mode, which is launched directly into the plasma chamber. The design concept draws on the development of similar devices used in tokamaks and stellerators. The first tests of the new coupling system are described below.

  9. University of Texas Alcohol and Drug-related Survey.

    Science.gov (United States)

    American Psychological Association, Washington, DC. Journal Supplement Abstract Service.

    The University of Texas Alcohol and Drug Related Survey is an 82-item questionnaire designed to measure student responses in five areas of critical concern: (a) demographic information, (b) current drinking behaviors, (c) attitudes toward drinking, (d) general knowledge concerning excessive use of alcohol, and (e) knowledge of and willingness to…

  10. Development of a special topics course on intelligent transportation systems for the Zachry Department of Civil Engineering of Texas A&M University.

    Science.gov (United States)

    2009-08-31

    With Intelligent Transportation Systems (ITS), engineers and system integrators blend emerging : detection/surveillance, communications, and computer technologies with transportation management and : control concepts to improve the safety and mobilit...

  11. Data acquisition and processing system of the electron cyclotron emission imaging system of the KSTAR tokamak.

    Science.gov (United States)

    Kim, J B; Lee, W; Yun, G S; Park, H K; Domier, C W; Luhmann, N C

    2010-10-01

    A new innovative electron cyclotron emission imaging (ECEI) diagnostic system for the Korean Superconducting Tokamak Advanced Research (KSTAR) produces a large amount of data. The design of the data acquisition and processing system of the ECEI diagnostic system should consider covering the large data production and flow. The system design is based on the layered structure scalable to the future extension to accommodate increasing data demands. Software architecture that allows a web-based monitoring of the operation status, remote experiment, and data analysis is discussed. The operating software will help machine operators and users validate the acquired data promptly, prepare next discharge, and enhance the experiment performance and data analysis in a distributed environment.

  12. Trends and variations in breast and colorectal cancer incidence from 1995 to 2011: a comparative study between Texas Cancer Registry and National Cancer Institute's Surveillance, Epidemiology and End Results data.

    Science.gov (United States)

    Liu, Zheyu; Zhang, Yefei; Franzin, Luisa; Cormier, Janice N; Chan, Wenyaw; Xu, Hua; Du, Xianglin L

    2015-04-01

    Few studies have examined the cancer incidence trends in the state of Texas, and no study has ever been conducted to compare the temporal trends of breast and colorectal cancer incidence in Texas with those of the National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) in the United States. This study aimed to conduct a parallel comparison between the Texas Cancer Registry and the National Cancer Institute's SEER on cancer incidence from 1995 to 2011. A total of 951,899 breast and colorectal cancer patients were included. Age-adjusted breast cancer incidence was 134.74 per 100,000 in Texas and 131.78 per 100,000 in SEER in 1995-2011, whereas age-adjusted colorectal cancer incidence was 50.52 per 100,000 in Texas and 49.44 per 100,000 in SEER. Breast cancer incidence increased from 1995 to 2001, decreased from 2002 to 2006, and then remained relatively stable from 2007 to 2011. For colorectal cancer, the incidence increased in 1995-1997, and then decreased continuously from 1998 to 2011 in Texas and SEER areas. Incidence rates and relative risks by age, gender and ethnicity were identical between Texas and SEER.

  13. Trends and variations in breast and colorectal cancer incidence from 1995 to 2011: A comparative study between Texas Cancer Registry and National Cancer Institute’s Surveillance, Epidemiology and End Results data

    Science.gov (United States)

    LIU, ZHEYU; ZHANG, YEFEI; FRANZIN, LUISA; CORMIER, JANICE N.; CHAN, WENYAW; XU, HUA; DU, XIANGLIN L.

    2015-01-01

    Few studies have examined the cancer incidence trends in the state of Texas, and no study has ever been conducted to compare the temporal trends of breast and colorectal cancer incidence in Texas with those of the National Cancer Institute’s Surveillance, Epidemiology and End Results (SEER) in the United States. This study aimed to conduct a parallel comparison between the Texas Cancer Registry and the National Cancer Institute’s SEER on cancer incidence from 1995 to 2011. A total of 951,899 breast and colorectal cancer patients were included. Age-adjusted breast cancer incidence was 134.74 per 100,000 in Texas and 131.78 per 100,000 in SEER in 1995–2011, whereas age-adjusted colorectal cancer incidence was 50.52 per 100,000 in Texas and 49.44 per 100,000 in SEER. Breast cancer incidence increased from 1995 to 2001, decreased from 2002 to 2006, and then remained relatively stable from 2007 to 2011. For colorectal cancer, the incidence increased in 1995–1997, and then decreased continuously from 1998 to 2011 in Texas and SEER areas. Incidence rates and relative risks by age, gender and ethnicity were identical between Texas and SEER. PMID:25672365

  14. Meeting Our Users where They Conference: A Texas A&M Model to Support Librarian Attendance at Subject-Specific Conferences

    Science.gov (United States)

    Hankins, Rebecca; Melgoza, Pauline; Seeger, Christina; Wan, Gary

    2009-01-01

    Today's academic librarian is frequently called upon to function as a subject specialist, with or without advanced degrees in other disciplines. One method of monitoring trends within a given field is to study its literature; another is to attend conferences in the discipline. Discipline-specific conference attendance by academic librarians…

  15. Results from the Project 8 phase-1 cyclotron radiation emission spectroscopy detector

    Science.gov (United States)

    Ashtari Esfahani, A.; Böser, S.; Claessens, C.; de Viveiros, L.; Doe, P. J.; Doeleman, S.; Fertl, M.; Finn, E. C.; Formaggio, J. A.; Guigue, M.; Heeger, K. M.; Jones, A. M.; Kazkaz, K.; LaRoque, B. H.; Machado, E.; Monreal, B.; Nikkel, J. A.; Oblath, N. S.; Robertson, R. G. H.; Rosenberg, L. J.; Rybka, G.; Saldaña, L.; Slocum, P. L.; Tedeschi, J. R.; Thümmler, T.; Vandevender, B. A.; Wachtendonk, M.; Weintroub, J.; Young, A.; Zayas, E.

    2017-09-01

    The Project 8 collaboration seeks to measure the absolute neutrino mass scale by means of precision spectroscopy of the beta decay of tritium. Our technique, cyclotron radiation emission spectroscopy, measures the frequency of the radiation emitted by electrons produced by decays in an ambient magnetic field. Because the cyclotron frequency is inversely proportional to the electron’s Lorentz factor, this is also a measurement of the electron’s energy. In order to demonstrate the viability of this technique, we have assembled and successfully operated a prototype system, which uses a rectangular waveguide to collect the cyclotron radiation from internal conversion electrons emitted from a gaseous 83m Kr source. Here we present the main design aspects of the first phase prototype, which was operated during parts of 2014 and 2015. We will also discuss the procedures used to analyze these data, along with the features which have been observed and the performance achieved to date.

  16. Accessibility condition of wave propagation and multicharged ion production in electron cyclotron resonance ion source plasma.

    Science.gov (United States)

    Kato, Yushi; Yano, Keisuke; Nishiokada, Takuya; Nagaya, Tomoki; Kimura, Daiju; Kumakura, Sho; Imai, Youta; Hagino, Shogo; Otsuka, Takuro; Sato, Fuminobu

    2016-02-01

    A new tandem type source of electron cyclotron resonance (ECR) plasmas has been constructing for producing synthesized ion beams in Osaka University. Magnetic mirror field configuration with octupole magnets can be controlled to various shape of ECR zones, namely, in the 2nd stage plasma to be available by a pair mirror and a supplemental coil. Noteworthy correlations between these magnetic configurations and production of multicharged ions are investigated in detail, as well as their optimum conditions. We have been considering accessibility condition of electromagnetic and electrostatic waves propagating in ECR ion source plasma, and then investigated their correspondence relationships with production of multicharged ions. It has been clarified that there exits efficient configuration of ECR zones for producing multicharged ion beams experimentally, and then has been suggested from detail accessibility conditions on the ECR plasma that new resonance, i.e., upper hybrid resonance, must have occurred.

  17. Capabilities of the ITER Electron Cyclotron Equatorial Launcher for Heating and Current Drive

    Directory of Open Access Journals (Sweden)

    Ramponi G.

    2012-09-01

    Full Text Available The ITER Electron Cyclotron Equatorial Launcher is designed to be one of the heating systems to assist and sustain the development of various ITER plasma scenarios starting with the very first plasma operation. Here the capabilities for Heating and Current Drive of this system are reviewed. In particular, the optimum launching conditions are investigated for two scenarios at burn, comparing toroidal and poloidal steering options. Then, the EC capabilities are investigated for different plasma parameters corresponding to various phases of the ITER plasma discharge, from current ramp-up up to burn, and for a wide range of magnetic field, focusing in particular on the EC potential for heating and for L to H-mode assist. It is found that the EC system can contribute to a wide range of heating scenarios during the ramp-up of the magnetic field, significantly increasing the applicable range as a function of magnetic field.

  18. Development of a special topics course on civil engineering project finance for the Zachry Department of Civil Engineering of Texas A&M University.

    Science.gov (United States)

    2011-05-01

    Experts predict that the highway trust fund will deteriorate rapidly over the course of the next several : years. This situation has led many state agencies to seek alternative financing methods that can meet both : social and economic needs. One pos...

  19. Social responsibility, politics, and fiscal viability: strategic issues in the development of a regional health care system for children in South Texas.

    Science.gov (United States)

    Robertson, K R; Stefl, M E

    1994-01-01

    A case study of the proposed development of a regional children's health care system in South Texas is described. Strategic plans for the system are overviewed and the community response to plans are presented. The political, social responsibility and fiscal viability issues raised are reviewed and the research literature base relevant to the health care needs of a key (Hispanic) market is summarized.

  20. Ion hole formation and nonlinear generation of electromagnetic ion cyclotron waves: THEMIS observations

    Science.gov (United States)

    Shoji, Masafumi; Miyoshi, Yoshizumi; Katoh, Yuto; Keika, Kunihiro; Angelopoulos, Vassilis; Kasahara, Satoshi; Asamura, Kazushi; Nakamura, Satoko; Omura, Yoshiharu

    2017-09-01

    Electromagnetic plasma waves are thought to be responsible for energy exchange between charged particles in space plasmas. Such an energy exchange process is evidenced by phase space holes identified in the ion distribution function and measurements of the dot product of the plasma wave electric field and the ion velocity. We develop a method to identify ion hole formation, taking into consideration the phase differences between the gyromotion of ions and the electromagnetic ion cyclotron (EMIC) waves. Using this method, we identify ion holes in the distribution function and the resulting nonlinear EMIC wave evolution from Time History of Events and Macroscale Interactions during Substorms (THEMIS) observations. These ion holes are key to wave growth and frequency drift by the ion currents through nonlinear wave-particle interactions, which are identified by a computer simulation in this study.

  1. Comparison of cyclotron and linacs for high-intensity-beam applications

    Energy Technology Data Exchange (ETDEWEB)

    Bhatia, T.S.; Jason, A.; Mottershead, C.T. [Los Alamos National Lab., NM (United States); Cooper, R. [Amparo Corp., NM (United States)

    1998-11-01

    This is the final report of a two-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The goals of this project were three-fold: (1) to understand the current level of cyclotron design expertise especially in the areas of space-charge modeling and simulation codes, (2) to develop a better understanding of the capabilities and limitations of circular machines, especially in the area of current limits, and (3) to stay abreast of the developments at other institutions in the area of high-current circular machines. These goals were partially met especially in the area of code development for the application of linac codes to motion of ions in a circular orbit. The authors were also able to continue their interactions with the other institutions working in this area.

  2. A Model for Health Professional Education in South Texas

    Science.gov (United States)

    Ramirez, Amelie; Vela, Leonel; Cigarroa, Francisco G.

    2008-01-01

    In 1997, The University of Texas Health Science Center at San Antonio established the Regional Academic Health Center (RAHC) for the Lower Rio Grande Valley in south Texas. Through medical education programs, research facilities, and partnerships with health-care providers, the RAHC aims to improve the health status and access to health services…

  3. Universities Response to Oil and Gas Industry Demands in South Texas (USA) and Tamaulipas (Mexico)

    Science.gov (United States)

    Navarro, Marco Aurelio

    2016-01-01

    Given the importance of hydrocarbons for this area, the purpose of this paper is to explore the response of universities to cope with new demands in the south of Texas and Tamaulipas, especially in relation to gas plays of Eagle Ford (Texas side) and Burgos Basin (Mexican side). To accomplish this task, in the first section of the paper a broad…

  4. On ion-cyclotron-resonance heating of the corona and solar wind

    Directory of Open Access Journals (Sweden)

    E. Marsch

    2003-01-01

    Full Text Available This paper concisely summarizes and critically reviews recent work by the authors on models of the heating of the solar corona by resonance of ions with high-frequency waves (up to the proton cyclotron frequency. The quasi-linear theory of pitch angle diffusion is presented in connection with relevant solar wind proton observations. Hybrid fluid-kinetic model equations, which include wave-particle interactions and collisions, are derived. Numerical solutions are discussed, representative of the inner corona and near-Sun solar wind. A semi-kinetic model for reduced velocity distributions is presented, yielding kinetic results for heavy ions in the solar corona. It is concluded that a self-consistent treatment of particle distributions and wave spectra is required, in order to adequately describe coronal physics and to obtain agreement with observations.

  5. Differences between the Texas phoenix palm phytoplasma and the ...

    African Journals Online (AJOL)

    ntushk

    sample extracted from a cabbage or sabal (Sabal palmetto) palm showing symptoms of Texas Phoenix decline (TPD) and ... genomic regions/genes that are useful indicators of taxonomic ... diamine tetra-acetic acid [EDTA, pH 8]). Presence of ...

  6. Outburst of GX304-1 Monitored with INTEGRAL: Positive Correlation Between the Cyclotron Line Energy and Flux

    Science.gov (United States)

    Klochkov, D.; Doroshenko, V.; Santangelo, A.; Staubert, R.; Ferrigno, C.; Kretschmar, P.; Caballero, I.; Wilms, J.; Kreykenbohm, I.; Pottschmidt, I.; hide

    2012-01-01

    Context. X-ray spectra of many accreting pulsars exhibit significant variations as a function of flux and thus of mass accretion rate. In some of these pulsars, the centroid energy of the cyclotron line(s), which characterizes the magnetic field strength at the site of the X-ray emission, has been found to vary systematically with flux. Aims. GX304-1 is a recently established cyclotron line source with a line energy around 50 keV. Since 2009, the pulsar shows regular outbursts with the peak flux exceeding one Crab. We analyze the INTEGRAL observations of the source during its outburst in January-February 2012. Methods. The observations covered almost the entire outburst, allowing us to measure the source's broad-band X-my spectrum at different flux levels. We report on the variations in the spectral parameters with luminosity and focus on the variations in the cyclotron line. Results. The centroid energy of the line is found to be positively correlated with the luminosity. We interpret this result as a manifestation of the local sub-Eddington (sub-critical) accretion regime operating in the source.

  7. On the influence of the shape of kappa distributions of ions and electrons on the ion-cyclotron instability

    Science.gov (United States)

    Ziebell, L. F.; Gaelzer, R.

    2017-10-01

    The dispersion relation for ion-cyclotron waves propagating along the direction of the ambient magnetic field is investigated numerically by considering different forms of kappa functions as velocity distributions of ions and electrons. General forms of kappa distributions, isotropic and anisotropic, are defined and used to obtain the dispersion relations for ion-cyclotron waves. With suitable choice of parameters, the general forms reduce to anisotropic versions of the kappa distributions most frequently employed in the literature. The analysis is focused in cases with a small value of the kappa index, for which the non thermal character of the kappa distributions is enhanced. The results show the effects of the superthermal tails of the velocity distributions of both particle species (ions and electrons) on the growth rate of the ion-cyclotron instability. It is seen that different forms of anisotropic kappa distributions, which are used in the current literature, can have a significantly different effect on the growth rates of the instability.

  8. A survey of the environmental literacy of high school junior and senior science students from a southeast Texas school district

    Science.gov (United States)

    Willis, Audrey Lynn

    The purpose of this study was to assess the environmental literacy of upper-level high school science students from a southeast Texas school district. The Secondary School Environmental Literacy Instrument (SSELI), an instrument designed to ascertain environmental literacy among high school students, was used to address research questions concerning (1) students, knowledge of ecology and environmental science; (2) students' attitudes towards the environment; (3) students, beliefs about the most critical environmental problems; (4) students, abilities to apply a number of issue-related skills within a particular environmental issue-oriented scenario; (5) students' perceived knowledge of and skills in the use of action strategies, and (6) students' behaviors in environmental actions over a six month period. The subject population surveyed consisted of 125 high school junior and senior science students from a southeast Texas school district. These students had completed at least two years of high school science. Since the data reflected behaviors that were self-reported by students and not actually observed, the quality of students, responses may have been compromised and thus considered a limitation. Data were analyzed using descriptive statistics. Correlational statistics were applied to the data. On average, 58% of the items on the knowledge test on ecology and environmental science were answered correctly; more than 65% of the respondents answered more than half of the items correctly. Students possessed a slightly positive attitude toward environmental concerns and protection but exhibited limited awareness of environmental problems. Students demonstrated moderate issue-related skill development. Students exhibited a readiness for and engagement in action but tended to limit their participation to two action areas (ecomanagement and consumer action). Students exhibited: (a) limited knowledge of ecological principles and environmental science, (b) a slightly

  9. Time evolution of bremsstrahlung and ion production of an electron cyclotron resonance ion source

    Energy Technology Data Exchange (ETDEWEB)

    Tarvainen, Ollie [Los Alamos National Laboratory; Ropponen, Tommi [UNIV OF JYVASKYLA; Jones, Peter [UNIV OF JYVASKYLA; Peura, Pauli [UNIV OF JYVASKYLA

    2008-01-01

    Bremsstrahlung radiation measurement is one of the most commonly used plasma diagnostics methods. Most of the bremsstrahlung measurements with electron cyclotron resonance (ECR) ion sources have been performed in continuous operation mode yielding information only on the steady state bremsstrahlung emission. This article describes the results of bremsstrahlung and ion current measurement with the JYFL 14 GHz ECRIS operated in pulsed mode. The experiments reveal information about the bremsstrahlung radiation in plasma conditions before reaching the equilibrium. The time scale of bremsstrahlung production is compared to ion production time scale for different charge states. The bremsstrahlung data is presented with 2 millisecond time intervals as a function of neutral gas pressure and microwave power. Data from hundreds of microwave pulses is combined in order to have a sufficient amount of events at each time step. The relevant plasma physics phenomena during both, the leading and the trailing edge of the RF pulse, are discussed.

  10. Dental care in Texas: An opportunity for implementing a comprehensive and patient-centric approach with special emphasis on cancer patients and survivors.

    Science.gov (United States)

    Tamí-Maury, Irene; Wagh, Aditya J; Abou Khalil, Nathalie E; Gritz, Ellen R; Chambers, Mark S

    2016-06-01

    To examine practices of dentists in Texas providing dental/oral care to cancer patients. Dental providers in Texas were invited via email to participate in an exploratory cross-sectional study. A non-probability voluntary convenience sampling procedure was used to recruit the sample. The online, anonymous, self-reported survey included questions to capture demographics, type of dental practice, services provided, and number of cancer patients. The study was approved by the Institutional Review Board of The university of Texas MD Anderson Cancer Center. A total of 655 dentists completed the questionnaire items. Results revealed that 62% of the respondents were 51-65 years old, predominantly (68%) male, Caucasian (81%) with their dental degrees awarded in the state of Texas (77%). 91% of the dentists provide dental care to patients who are currently undergoing cancer treatment or have a history of cancer. However, 80% of the dental providers do not teach oral self-exam to their patients, which may include cancer survivors or those undergoing cancer treatment, while 32% dentists do not deliver brief interventions for effectively motivating and assisting tobacco users to quit. Because Texas, especially Houston, is known for world-class cancer care, dentists in the state are more likely to provide dental care to oncologic patients, especially emergency dental procedures in cancer patients facing some of the side effects of cancer treatment. Careful monitoring of oral health and reducing tobacco use are especially important during and after cancer therapy to prevent, detect, and treat complications as soon as possible. A further step in oral care for cancer patients and survivors is to train patients how to perform regular oral self-examination and to provide tobacco users with cessation counseling as part of their dental/oral treatment. These simple but comprehensive approaches, along with regular dental visits, will positively impact the health-related outcomes for

  11. Trends and variations in breast and colorectal cancer incidence from 1995 to 2011: A comparative study between Texas Cancer Registry and National Cancer Institute?s Surveillance, Epidemiology and End Results data

    OpenAIRE

    Liu, Zheyu; Zhang, Yefei; FRANZIN, LUISA; Cormier, Janice N.; Chan, Wenyaw; Xu, Hua; Du, Xianglin L.

    2015-01-01

    Few studies have examined the cancer incidence trends in the state of Texas, and no study has ever been conducted to compare the temporal trends of breast and colorectal cancer incidence in Texas with those of the National Cancer Institute?s Surveillance, Epidemiology and End Results (SEER) in the United States. This study aimed to conduct a parallel comparison between the Texas Cancer Registry and the National Cancer Institute?s SEER on cancer incidence from 1995 to 2011. A total of 951,899 ...

  12. Advanced Placement English Exam Scores: A Comparison of Scores for Hispanic Students from California, Texas, and Arizona

    Science.gov (United States)

    Koch, Bevan; Slate, John R.; Moore, George W.

    2016-01-01

    We compared the performance of Hispanic students from California, Texas, and Arizona on the two Advanced Placement (AP) English exams (i.e., English Language and Composition and English Literature and Composition) using archival data from the College Board from 1997 through 2012. Pearson chi-square tests yielded statistically significant…

  13. A unique funding opportunity for public health in Texas.

    Science.gov (United States)

    Schlenker, Thomas; Huber, Carol A

    2015-01-01

    In addition to the Affordable Care Act, states are more frequently turning to Medicaid waivers to achieve the "Triple Aim" goals of improving the experience of care, improving population health, and reducing per capita costs. These demonstration waivers provide opportunities to test innovative ways to finance and deliver care. Texas is currently implementing a waiver known as the Transformation and Quality Improvement Program. Its inclusion of public health agencies is a unique approach to a system typically limited to traditional providers. San Antonio Metropolitan Health District is one public health agency taking advantage of this new funding opportunity to implement 6 new or expanded programs targeting health issues of highest priority in this south Texas region. This article discusses the use of Medicaid waivers and the advantages and challenges of public health agency participation.

  14. A Texas Flood from Land to Ocean Observed by SMAP

    Science.gov (United States)

    Fournier, S.; Reager, J. T., II; Lee, T.; Vazquez, J.; David, C. H.; Gierach, M. M.

    2016-12-01

    Floods are natural hazards that can have damaging impacts not only on affected land areas but also on the adjacent coastal waters. NASA's Soil Moisture Active Passive (SMAP) mission provides measurements of both surface soil moisture and sea surface salinity (SSS), offering the opportunity to study the effects of flooding events on both terrestrial and marine environments. Here, we present analysis of a severe flood that occurred in May 2015 in Texas using SMAP observations and ancillary satellite and in situ data that describe the precipitation intensity, the evolving saturation state of the land surface, the flood discharge peak, and the resulting freshwater plume in the Gulf of Mexico. We describe the spatiotemporal evolution of the different variables, their relationships, and the associated physical processes. Specifically, we identify a freshwater plume in the north-central Gulf, being distinct from the typical Mississippi River plume, that is attributable to the Texas flood.

  15. Integrated analysis of production potential and profitability of a horizontal well in the Lower Glen Rose Formation, Maverick County, Texas

    Energy Technology Data Exchange (ETDEWEB)

    Ammer, J.R.; Mroz, T.H.; Zammerilli, A.M.; Yost, A.B. II [Dept. of Energy, Morgantown, WV (United States); Muncey, J.G.; Hegeman, P.S.

    1995-03-01

    The U.S. Department of Energy/Morgantown Energy Technology Center (DOE/METC) awarded a contract in 1991 to Prime Energy Corporation (PEC) to demonstrate the benefit of using horizontal wells to recover gas from low permeability formations. The project area was located in the Chittim field of Maverick County, Texas. The Lower Glen Rose Formation in the Chittim field was a promising horizontal well candidate based on the heterogenous nature of the reservoir (suggested by large well-to-well variances in reserves) and the low percentage of economical vertical wells. Since there was substantial evidence of reservoir heterogeneity, it was unknown whether the selected, wellsite would penetrate a reservoir with the desired properties for a horizontal well. Thus, an integrated team was formed to combine geologic analysis, seismic interpretation, reservoir engineering, reservoir simulation, and economic assessment to analyze the production potential and profitability of completing a horizontal well in the Lower Glen Rose formation.

  16. Production and decay of chlorine ion excited species in an electron cyclotron resonance ion source plasma

    Energy Technology Data Exchange (ETDEWEB)

    Santos, J P; Martins, M C; Parente, F [Centro de Fisica Atomica, CFA, Departamento de Fisica, Faculdade de Ciencias e Tecnologia, FCT, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Costa, A M; Marques, J P [Centro de Fisica Atomica, CFA, Departamento de Fisica, Faculdade de Ciencias, FCUL, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa (Portugal); Indelicato, P, E-mail: jps@fct.unl.pt [Laboratoire Kastler Brossel, Ecole Normale Superieure, CNRS, Universite P et M Curie-Paris 6, Case 74, 4 place Jussieu, 75252 Paris Cedex 05 (France)

    2011-06-15

    The most important processes for the creation of chlorine ion excited states from the ground configurations of Cl{sup 10+} to Cl{sup 15+} ions in an electron cyclotron resonance ion source, leading to the emission of K x-ray lines, were studied. Theoretical values for inner-shell excitation and ionization cross-sections, including double KL and triple KLL ionization, transition probabilities and energies for the de-excitation processes, were calculated in the framework of the multi-configuration Dirac-Fock method. With reasonable assumptions about the electron energy distribution, a theoretical K{alpha} x-ray spectrum was obtained, which was then compared with recent experimental data.

  17. Prospects for advanced electron cyclotron resonance and electron beam ion source charge breeding methods for EURISOL.

    Science.gov (United States)

    Delahaye, P; Galata, A; Angot, J; Ban, G; Celona, L; Choinski, J; Gmaj, P; Jakubowski, A; Jardin, P; Kalvas, T; Koivisto, H; Kolhinen, V; Lamy, T; Lunney, D; Maunoury, L; Porcellato, A M; Prete, G F; Steckiewicz, O; Sortais, P; Thuillier, T; Tarvainen, O; Traykov, E; Varenne, F; Wenander, F

    2012-02-01

    As the most ambitious concept of isotope separation on line (ISOL) facility, EURISOL aims at producing unprecedented intensities of post-accelerated radioactive isotopes. Charge breeding, which transforms the charge state of radioactive beams from 1+ to an n+ charge state prior to post-acceleration, is a key technology which has to overcome the following challenges: high charge states for high energies, efficiency, rapidity and purity. On the roadmap to EURISOL, a dedicated R&D is being undertaken to push forward the frontiers of the present state-of-the-art techniques which use either electron cyclotron resonance or electron beam ion sources. We describe here the guidelines of this R&D.

  18. Surface-Induced Dissociation of Protein Complexes in a Hybrid Fourier Transform Ion Cyclotron Resonance Mass Spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Jing; Zhou, Mowei; Gilbert, Joshua D.; Wolff, Jeremy J.; Somogyi, Árpád; Pedder, Randall E.; Quintyn, Royston S.; Morrison, Lindsay J.; Easterling, Michael L.; Paša-Tolić, Ljiljana; Wysocki, Vicki H.

    2017-01-03

    Mass spectrometry continues to develop as a valuable tool in the analysis of proteins and protein complexes. In protein complex mass spectrometry studies, surface-induced dissociation (SID) has been successfully applied in quadrupole time-of-flight (Q-TOF) instruments. SID provides structural information on non-covalent protein complexes that is complementary to other techniques. However, the mass resolution of Q-TOF instruments can limit the information that can be obtained for protein complexes by SID. Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) provides ultrahigh resolution and ultrahigh mass accuracy measurements. In this study, an SID device was designed and successfully installed in a hybrid FT-ICR instrument in place of the standard gas collision cell. The SID-FT-ICR platform has been tested with several protein complex systems (homooligomers, a heterooligomer, and a protein-ligand complex, ranging from 53 kDa to 85 kDa), and the results are consistent with data previously acquired on Q-TOF platforms, matching predictions from known protein interface information. SID fragments with the same m/z but different charge states are well-resolved based on distinct spacing between adjacent isotope peaks, and the addition of metal cations and ligands can also be isotopically resolved with the ultrahigh mass resolution available in FT-ICR.

  19. Texas National Coastal Assessment (2000-2004): challenges, solutions, lessons learned and future directions.

    Science.gov (United States)

    Simons, James D; Smith, Charles R

    2009-03-01

    The Texas National Coastal Assessment (NCA) program began with the immediate challenge of integrating the NCA effort with Texas Parks and Wildlife Department's (TPWD) Coastal Fisheries Division and its existing probabilistic Fishery Independent Monitoring Program. Close coordination and detailed planning along with a novel two boat sampling operation helped to make this alliance work. Partnerships with National Estuary Programs and the Texas Commission on Environmental Quality (TCEQ) greatly improved coverage of the Texas coast over the initial fifty station design. Airboats, biobags, and polyvinyl chloride (PVC) corers were instrumental in overcoming numerous technical challenges. NCA data provide a more complete assessment of water