Presentation on theme: "Wir schaffen Wissen – heute für morgen 5. April 2015PSI,5. April 2015PSI, Paul Scherrer Institut Diamond Detectors for Transactinide Chemistry Patrick."— Presentation transcript:
Wir schaffen Wissen – heute für morgen 5. April 2015PSI,5. April 2015PSI, Paul Scherrer Institut Diamond Detectors for Transactinide Chemistry Patrick Steinegger
Outline Introduction to transactinide chemistry The COLD thermochromatography setup and resulting deposition pattern Problems with common Si PIN-diodes and possible application of diamond detectors First trials using diamond detectors 5. April 2015PSI, Seite 2
Transactinide Chemistry Experiments We are interested in the chemical properties of transactinide elements ( Z > 103 ) with a special focus on the so-called superheavy elements ( SHE ). For instance, this is achieved by deducing adsorption enthalpies (- H ads ) using the thermochormatography setup with the Cryo – OnLine – Detector ( COLD ). I. Zvara, Isotopenpraxis 26 ( 1990 ) 6, pp. 251 – 258 T = 35 °CT = -180°C Detector array 5. April 2015PSI, Seite 3
5. April 2015PSI, Schematic Experimental Setup 5. April 2015PSI, Seite 4  Y. Oganessian et al., Phys. Rev. C 70 ( 2004 )  R. Eichler et al., Nature 447 ( 2007 ), pp. 72 – 75 Hg ( ) Rn ( ) Decay properties of SHE 114 (observed at FLNR in 2004  ) 
The COLD Detector Array 5. April 2015PSI, Seite 5
5. April 2015PSI,5. April 2015PSI, Seite 6 Deposition of 185 Hg and 219 Rn along COLD Monte Carlo Simulation Temperature limitation at T max ≈ 40 °C Higher temperatures would enable the determination of adsorption enthalpies of elements with even higher adsorption characteristics on gold ( e.g. 113, Tl, Hg, Pb, etc. → e.g. 10 diamond sandwitch detectors in the COLD array for the „hot region“).
5. April 2015PSI, Deposition of Element Cn ( 112 ) 5. April 2015PSI, Seite 7 (-5°C) (-21°C) (-39°C) (-124°C) (-28°C)
Further Diamond Detector Applications Since diamond detectors can be operated near a hot source (e.g. oven), they are perfectly suitable for isothermal vacuumchormatography experiments: Diamond Detector (cooled catcher) Heat source (e.g. resistance oven) Read-out Electron. 5. April 2015PSI, Seite 8 The transition from gas chromatography towards vacuum chromatography (either isothermal or thermal) has the following advantages: - No aerosol transport and therefore lower background (decreased random rate) - Less pollutions (organic impurities, water, etc.) → clean stationary surfaces - Better energy resolution in case of vacuum thermochromatography - Less chromatographic resolution due to random walk The possibility of positioning the detector near an IR, UV or VIS source or the operation in the vicinity of an oven is another important feature for other experiments (thermal release expperiments → T ≈ 1200 °C).
Isothermal Vacuumchromatography 5. April 2015PSI, Seite 9
Further Diamond Detector Applications 5. April 2015PSI, Seite 10 Another option are online studies of electrochemically spontanous deposition of superheavy elements on metallized detector surfaces. So far, applied Si detector material was usually damaged due to electrode surface „pinholes“.
5. April 2015PSI, First Trials with CVD / B-doped Diamond 5. April 2015PSI, Seite 11 Diamond “glued” and wire-bonded onto ceramic carrier 3-line source ( 239 Pu, 241 Am, 244 Cm ) DBS Microwave SA
First Trials with Element6 scCVD Diamond So far it has not yet been possible to record a spectrum. We use(d) different setups - among them the one applied by Pomorski et al.  and again another with the diamond glued on a ceramic carrier. 5. April 2015PSI, Seite 12  M. Pomorski, Phys. Stat. Sol. (a) 203 ( 2006 ) 12, pp – 3160 Ceramic carrier Glued diamondWire bonding Voltage connections Signal out Swan Research 10 nm Cr / 100 nm Au ( both sides)
5. April 2015PSI,5. April 2015PSI, Seite 13 Thank you for your kind attention!