Sökning: "molecular beam mass spectrometer"

Visar resultat 1 - 5 av 8 avhandlingar innehållade orden molecular beam mass spectrometer.

  1. 1. The Penning trap mass spectrometer SMILETRAP II and evaporative cooling of highly-charged ions

    Författare :Matthias Hobein; Reinhold Schuch; David Lunney; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Penning trap; Precision mass spectrometry; Atomic mass; Highly-charged ions; Evaporative cooling; Coherent oscillation; Ion beam emittance; Atomic physics; Atomfysik; fysik; Physics;

    Sammanfattning : Accurate mass values have wide-ranging applications in physics and metrology, allowing, for example, to test quantum electrodynamics and fundamental symmetries, to determine fundamental constants, and to establish weight standards. This thesis describes the new high-precision double-Penning trap mass spectrometer SMILETRAP II which aims at relative uncertainties in the mass determination of 10-10 and below. LÄS MER

  3. 2. Synthesis of complex organics via molecular growth mechanisms : Combined experimental and theoretical studies on ion-neutral reactions of C2H2N+ with ubiquitous hydrocarbons in Titan's ionosphere

    Författare :Pantea Fathi; Wolf Geppert; Paul Scheier; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Astrochemistry; Complex molecules; Ion-neutral reactions; Mass spectrometry; Planetary and satellite atmospheres; Titan; kemisk fysik; Chemical Physics;

    Sammanfattning : To provide insights on the molecular growth mechanisms leading to large carbon and nitrogen-bearing species in Titan’s ionosphere, laboratory measurements of ion-neutral reactions were conducted and the results are presented in the following doctoral dissertation. The product ions of the C2H2N+ reactions with saturated and unsaturated neutral hydrocarbons have been investigated using Guided Ion Beam Mass Spectrometer (GIB-MS). LÄS MER

  4. 3. Stark Spectroscopy, Lifetimes and Coherence Effects in Diatomic Molecular Systems

    Författare :Annie Hansson; Peder Royen; Michel Herman; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; diatomic; dipole moment; Stark effect; lifetimes; transition moment; coherence effects; EIT; Autler-Townes; Chemical physics; Kemisk fysik;

    Sammanfattning : In this dissertation is exemplified how different laser based methods are applied in high-resolution spectroscopic studies of internal properties of diatomic molecules.A molecular beam apparatus assembly is described, where a laser ablation source is combined with a time-of-flight mass spectrometer. LÄS MER

  5. 4. Mechanisms of Anion Reactions from the lab to ionospheres

    Författare :Fredrik Lindén; Wolf D. Geppert; Henrik Cederquist; Henning Zettergren; Einar Uggerud; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ab initio; anion; complex molecules; cross section; electron transfer; heavy ions; ionosphere; nitriles; quantum chemistry; spectroscopy; kemisk fysik; Chemical Physics;

    Sammanfattning : A multitude of heavy neutral and ionic molecules have been discovered by the Cassini Plasma Spectrometer in the ionosphere of Saturn's largest moon Titan. However, only three cyano anions were explicitly identified there, namely CN-, C3N- and C5N-. LÄS MER

  7. 5. Experimental studies of cluster ions containing water, ammonia, pyridine and bisulphate

    Författare :Mauritz Johan Ryding; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; clusters; ions; water; ammonia; pyridine; bisulphate; cross sections; collision induced dissociation CID ; kinetic modelling; electrospray ionization ESI ; time-of-flight TOF ; mass spectrometry;

    Sammanfattning : Molecular cluster ions are fascinating subjects of study. Bridging the size gap between molecules and bulk, they often display non-trivial size dependent behaviour and properties. LÄS MER