Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 71 (2000), S. 836-838 
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: For the International Fusion Materials Irradiation Facility (IFMIF) scenario, a 140 mA deuterium beam in continuous wave (cw) mode with an atomic yield of above 85% is required. The normalized root-mean-square emittance should be less than 0.2 π mm mrad at the entrance of a RFQ. As part of a conceptual design for IFMIF, a new ion source has been developed and is tested at the Institut für Angewandte Physik in Frankfurt. The ion source is of the volume type with a tungsten cathode driving the discharge. Both cw and pulsed mode are possible and were studied. First experiments were carried out with deuterium. 80 mA deuterons with a D+ fraction of above 90% were extracted [A. Maser et al., Rev. Sci. Instrum. 67, 1054 (1996)]. In order to avoid neutron generation by the d–d reaction, hydrogen was used instead of deuterium later on. As far as the ion source and plasma production processes are concerned, the use of hydrogen instead of deuterium is equivalent because of their similar atomic shells. Recently, a 200 mA proton beam at 55 kV was extracted in cw mode (according to Child–Langmuir, 200 mA H+ corresponds to 140 mA D+) with a H+ fraction of 93%. This article will give a detailed description of the ion source and the essential experimental results. Especially, the influence of important physical parameters (such as discharge current and strength of the filter field) on the H+ fraction was studied. By using different kinds of auxiliary gases, the influence on the H+ fraction and the noise level were investigated, too. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 73 (2002), S. 723-725 
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: Increasing the brightness of the ion beam is a typical demand for any accelerator. In order to fill the heavy ion synchrotron (SIS) up to the space charge limit, higher pulse currents are necessary. The UNILAC is operated with a pulse length up to 6 ms and a repetition rate up to 50 s−1. For the injection into the SIS a pulse length of 300 μs at 0.3 s−1 is required. The transverse acceptance of the RFQ is 138 π mm mrad. According to Child's law, the ion current density which can be extracted from a plasma source is for the space charge limited flow proportional to Φ1.5/d2. With Φ and d denoting the extraction voltage and the width of the extraction gap. One approach to generate higher ion currents is to increase the extraction voltage in the regularly used extraction system. However, the required beam velocity is fixed by the RFQ structure with 2.2 keV/u. The mass-to-charge ratio which is to be accelerated can be between 1 and 65, resulting in a total voltage drop from 2.2 up to 143 kV (extraction and postacceleration voltage). The other approach is to decrease the gap width in the extraction system, but there is an optimum in the aspect ratio. To generate an ion beam with a higher current at low energy, a triode extraction system operated in accel–decel (Uacc,Udec) mode is a possible solution. By applying a negative potential at the second electrode a higher extraction field strength can be achieved. The effects of extraction field, arc current, and ion energy on the extracted ion beam current and its emittance were investigated. © 2002 American Institute of Physics.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 73 (2002), S. 1027-1029 
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: For the International Fusion Materials Irradiation Facility project (IFMIF) the Institut für Angewandte Physik at the University of Frankfurt is concerned with developing a high current proton/deuteron ion source. The 1999 "Frankfurt 200 mA Proton Source" is a volume type belonging to the high-efficient ion-sources family. This type of ion source has proven its capability to produce high-current ion beams of a single mass-to-charge ratio at very low-beam emittances. The arc discharge ion source delivers a 200 mA full beam (93% protons) at 55 keV with very high-beam intensities (outlet aperture 8 mm diam). Thus, the beam requirements for the IFMIF project are fulfilled. After having done the basic plasma investigation with a 127° cylinder spectrometer, the quality of the ion beam was a point of interest. Therefore, the beam emittance was measured with a conventional slit-grid measurement device. The goal was to measure the beam emittance at high-beam currents. The article will give a detailed description of the measurement of a 56 mA beam at 26 keV with 85% protons. Theoretical considerations of the emittance value, given by ion temperature and aberrations of the extraction system, allows an estimation of the emittance of a 170 mA at 55 keV proton beam. In a second step, an estimation of a postaccelerated 140 mA at 100 keV deuteron beam was completed. © 2002 American Institute of Physics.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 73 (2002), S. 1024-1026 
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: The high current injector (HSI) was set into operation in 1999. The maximum ratio of mass to charge state of this new injector has been increased from 25 to 65 with a lower injection velocity of 2.2 keV/u (11.7 keV/u before). The space charge limit of the RFQ (0.25*A/ζ[mA]) was reached for argon and lighter ions but not for U4+ or rare isotopes. For that reason further modifications of the high current ion injector, e.g., geometry of the acceleration gap, solenoid for focusing, were necessary. Here we present beam emittance measurements after the acceleration system for different ion species with beam energies up to 150 keV and beam currents up to 100 mA. For the measurements a multicusp ion source with a multiaperture accel–decel extraction system has been used to produce high ion beam currents in low charge states. The commissioning has been made using an Ar+ beam. This ion beam is easy to produce in nearly one charge state with emission current densities up to 150 mA/cm2. The emittance measurements will be presented in view of the two main dependencies: the focussing strength of the acceleration gap and the space charge forces in the acceleration gap. © 2002 American Institute of Physics.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Springer
    International journal of infrared and millimeter waves 15 (1994), S. 1105-1124 
    ISSN: 1572-9559
    Keywords: Resource Letter ; Magnetic Materials ; Plasmas ; Ferrites
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract This work is a collection of selected, significant references focussing upon magnetic materials and their interaction with electromagnetic fields. The major topics included are ferrites, plasmas (both atmospheric and laboratory), magnetic composites, magnetic dielectric fluids, ferroelectric liquid crystals. Sections discussing general magnetic materials and phenomena are also included.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Springer
    International journal of infrared and millimeter waves 15 (1994), S. 1981-2000 
    ISSN: 1572-9559
    Keywords: Magnetic Materials ; Plasmas ; Ferrites
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract This work is a collection of selected, significant references focussing upon magnetic materials and their interaction with electromagnetic fields. The major topics included are ferrites, plasmas (both atmospheric and laboratory), magnetic composites, magnetic dielectric fluids, ferroelectric liquid crystals. Sections discussing general magnetic materials and phenomena are also included.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für die chemische Industrie 22 (1909), S. 1361-1363 
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...