Bibliothek

feed icon rss

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
  • 1
    Digitale Medien
    Digitale Medien
    s.l. : American Chemical Society
    Biochemistry 19 (1980), S. 1805-1813 
    ISSN: 1520-4995
    Quelle: ACS Legacy Archives
    Thema: Biologie , Chemie und Pharmazie
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 2
    Digitale Medien
    Digitale Medien
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 73 (2002), S. 528-530 
    ISSN: 1089-7623
    Quelle: AIP Digital Archive
    Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik
    Notizen: In order to study the possibilities to produce high currents of pulsed heavy ion beams dedicated to synchrotron injection, two new approaches of ECR devices are now underway. The basic principle consists in maintaining a functioning point of the source with the highest density as possible and a minimum confinement time for the production of a given charge state. It means that for a constant neτi product we try to maximize ne and minimize τi. For this purpose two experiments are in progress at ISN/Grenoblea and IAP/Nizhny Novgorod.b The first one consists of using a minimum |B| magnetic structure with a 1.8 mirror ratio characteristic value with a 28 GHz frequency injection. In this case we explore different functioning points up to 10 kW of UHF power. The second one consists of a simple mirror magnetic system (simple mirror ion source, SMIS) working at 37.5 GHz with a mirror ratio up to 3 (2.5 T) where we study discharges with a peak power up to 100 kW. We will show that, in spite of a very short rising time of the current, we can maintain the production of multicharged ions and that we can observe very high current densities. In the future, the challenge will be the design of an extraction geometry matching theses current levels. © 2002 American Institute of Physics.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 3
    ISSN: 1089-7623
    Quelle: AIP Digital Archive
    Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik
    Notizen: The backward and forward injection of a 1+ ion beam in a MINIMAFIOS type electron cyclotron resonance ion source (ECRIS) have given good results for the 1+→n+ method. Due to the technological simplicity of the forward injection, additional experiments have been performed with this configuration. Different primary sources (1+) have been used for the injection (2.45 GHz ECRIS, hollow cathode source, simplified 10 GHz NANOGAN type ECRIS), an increase of the performances has already been obtained (Zn, Kr, Ar), and a measurement of the absolute efficiency with the NANOGAN type-MINIMAFIOS association is performed. Due to the high performance of the 10 GHz CAPRICE source used as a highly charged ion injector in the first cyclotron of SARA (Système Accélérateur Rhône-Alpes), it has been tested as a different n+ source for the 1+→n+ method. In this purpose, a low energy spread–low emittance thermoionization Rb ion source has been used as 1+ injector. A standard operation of the SARA-CAPRICE source has been kept with respect to the microwave coupling. The spectra of the Rbn+ ions extracted are compared when using N2 and O2 as support gases. The highest efficiency is obtained for the Rb13+. © 1998 American Institute of Physics.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 4
    Digitale Medien
    Digitale Medien
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 71 (2000), S. 612-616 
    ISSN: 1089-7623
    Quelle: AIP Digital Archive
    Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik
    Notizen: Short life radioactive beams presently need charge breeders either for continuous or pulsed postaccelerators. Until recently these charge breeders were mainly based on stripper foils and or electron beam ion source projects associated with ion trap bunching devices. In 1995 however, we demonstrated the feasibility of radioactive electron cyclotron resonance ion source (ECRIS) charge breeders with rather good efficiencies working in continuous regime and well adapted for continuous postaccelerators. In 1998, we demonstrated also the feasibility of pulsed ECR ion traps (ECRITs) which are well adapted for pulsed postaccelerators with short life radioactive ion bunches. In this article, we explain the basic principles of these devices shortly named (1+n+) ECR systems and compare their characteristics with other systems. More precise results are given in companion articles at this meeting. © 2000 American Institute of Physics.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 5
    Digitale Medien
    Digitale Medien
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 71 (2000), S. 617-622 
    ISSN: 1089-7623
    Quelle: AIP Digital Archive
    Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik
    Notizen: Initially developed for radioactive ion beam production, the electron cyclotron resource (ECR) charge breeder shows that the beam injection of a primary beam inside an ECR ion source is a very general process for beam production. In this article we will review the latest results obtained on the ISN Grenoble test bench for the production of clockwise (CW) or pulsed metallic ion beams with the so-called "1+/n+" method. New results are given for CW operation where the efficiency is particularly optimized for application to multicharged radioactive ion production (for example, 3.5% for Zn1+→Zn9+, 4.2% for Pb1+→Pb24+, 5% for Rb1+→Rb15+). Different ion sources have been used to study the variation of the efficiency as a function of the energy of the 1+ primary beam. Charge state distributions are especially measured for Pb and Rb ions. A new mode of operation, the electron cyclotron resonance ion trap breeder/buncher, which permits the trapping and the bunching of the n+ ion beam is demonstrated and experimentally verified. The injection of a 400 nAeRb1+ ion beam leads to a 11.5 μAe peak current of the Rb15+ ion beam extracted during the first ms. The temporal evolution of the cumulated particle transformation and trapping efficiency is measured in the case of Rb15+. This new method shows that it is possible to modify the time structure of the injected beam, just by trapping the ions inside the plasma and re-extracting them by using the "afterglow pulsed mode." It will also be shown that it is possible to produce "multi-charged metallic ions" by using a primary source for the dissociation of a complex molecule and then by injecting the low charge state beam inside the multicharged electron cyclotron resonance ion source. A preliminary example will be presented for the production of U26+ by injection of U3+ obtained from dissociation of UF6 gas. © 2000 American Institute of Physics.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 6
    Digitale Medien
    Digitale Medien
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 69 (1998), S. 1302-1310 
    ISSN: 1089-7623
    Quelle: AIP Digital Archive
    Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik
    Notizen: Low charge state electron cyclotron resonance ion source (ECRIS) work since 1965 and high charge state ECRIS since 1974. These ECR sources are categorized into three main sections: (1) Low charged ion (ECRIS) inside simple magnetic mirror or Bucket configurations. (2) High charged ion ECRIS inside min-B mirror configurations. (3) Short pulsed ECRIS with highly charged ions where the ion confinement is disturbed for a short while, which allows the extraction of intense ion pulses. Future prospects are based on rational scaling of the magnetic confinement including high B modes, by increasing the radio frequency (rf) frequency and ECR magnetic field. In this case, charge exchange has to be minimized and plasma instabilities have to be avoided. However, clever empirical tricks lead also to outstanding not always predicted improvements. Let us cite: optimized rf plasma coupling, electron guns, gas mixing, wall coating, biased electrodes, and more recently multiple ECR frequency heating. ECRIS have not yet achieved their optimal possibilities. Let us wait for the next generation of superconducting ECRIS and the possible use of subcentimeter waves. © 1998 American Institute of Physics.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 7
    ISSN: 1089-7623
    Quelle: AIP Digital Archive
    Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik
    Notizen: This paper deals with a new concept of the full scale ion plasma injector for ECRIPAC—a new supercompact collective action accelerator for ions. The injector has an electron cyclotron resonance (ECR) 10 GHz "min B'' quadrupolar magnetic structure which, in contrast to the traditional ECR ion sources, allows the microwaves to penetrate on the periphery of the plasma, and also on the axis of the plasma in conditions close to the first and second Bernstein modes. © 1996 American Institute of Physics.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 8
    Digitale Medien
    Digitale Medien
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 69 (1998), S. 613-613 
    ISSN: 1089-7623
    Quelle: AIP Digital Archive
    Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik
    Notizen: Low charge state electron cyclotron resonance ion source (ECRIS) work since 1965 and high charge state ECRIS since 1974. These ECR sources are categorized into three main sections: (1) Low charged ion (ECRIS) inside simple magnetic mirror or Bucket configurations. (2) High charged ion ECRIS inside min-B mirror configurations. (3) Short pulsed ECRIS with highly charged ions where the ion confinement is disturbed for a short while, which allows the extraction of intense ion pulses. Future prospects are based on rational scaling of the magnetic confinement including high B modes, by increasing the radio frequency (rf) frequency and ECR magnetic field. In this case, charge exchange has to be minimized and plasma instabilities have to be avoided. However, clever empirical tricks lead also to outstanding not always predicted improvements. Let us cite: optimized rf plasma coupling, electron guns, gas mixing, wall coating, biased electrodes, and more recently multiple ECR frequency heating. ECRIS have not yet achieved their optimal possibilities. Let us wait for the next generation of superconducting ECRIS and the possible use of subcentimeter waves. © 1998 American Institute of Physics.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 9
    ISSN: 1089-7623
    Quelle: AIP Digital Archive
    Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik
    Notizen: Two types of 1+→n+ ion conversion devices have been developed for the Production, Ionisation, Accélération de Faisceaux Exotiques project. Both can be utilized for short lived radioactive ions beams. They are based on collisions inside an electron cyclotron resonance ion source (ECRIS). They transform a 1+ ion beam into a n+ ion beam in less than 0.1 s. In the first device, ions are introduced into the ECR plasma through the extraction hole (backward injection), in the second device they are introduced as usual (forward injection). The particle conversion efficiencies can reach for noble gases ∼6.5% for Kr9+/Kr1+ and for alkali elements ∼2.8% for Rb9+/Rb1+. © 1997 American Institute of Physics.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 10
    Digitale Medien
    Digitale Medien
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 67 (1996), S. 1281-1285 
    ISSN: 1089-7623
    Quelle: AIP Digital Archive
    Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik
    Notizen: ISOL–MAFIOS is a high-efficiency Min B ECRIS charge state breeder for short-lived ISOL beams in the PIAFE project. The ISOL species issuing from a bombarded target are locally ionized (1+) in a given ion source (ISOLDE type). They are then accelerated, magnetically selected, and transported in a long beam line, before being adequately introduced into ISOL–MAFIOS operating in continuous mode. In this system, an ECR plasma (created with a support gas) replaces the usual solid catcher. The ISOL–MAFIOS system captures the (1+) ions and transforms them into (q+) ions. If we call, overall efficiency of ISOL–MAFIOS the ratio of the beam intensities: I(q+) after the magnetic selector/I(1+) before entering in the source, we find for example for Rubidium IRb9+/IRb1+≈120 enA/1000 enA and a ratio at least two times larger for IKr9+/IKr1+. Moreover, an even more important result of ISOL–MAFIOS is that the release time+ionization time is of the order of 10−2 s instead of many seconds for a solid-state catcher. Thus in the PIAFE project isotopes whose half life times are (approximately-greater-than)10−2 s become utilizable for acceleration in the two-cyclotron SARA. Note that in the PIAFE project the (1+) ISOL ions are produced by neutron bombardment of a U target inside the high flux reactor ILL and not by the bombardment of a target by a primary ion beam. © 1996 American Institute of Physics.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...