Photon Echoes in Krypton and Xenon Discharges

L. Dana, Pierre Laures

O. V. Lukashina, А. Н. Ораевский, Игорь Евгеньевич Проценко

Experimental investigations were made of the vacuum ultraviolet spectrum of a discharge in a cryogenic plasma formed from a mixture of krypton and xenon. An increase in the continuum intensity was observed when the discharge in krypton was cooled. Anomalous amplification of the vacuum ultraviolet continuum of krypton was observed when a small amount of xenon was added.

Patrick Stollenwerk, K. Bailey, Daria B. Koch +4 more

We demonstrate excitation of metastable krypton and xenon beams using a vacuum ultraviolet lamp and directly compare the performance of this method to metastable excitation based on a radio-frequency-driven plasma discharge. In our apparatus, lamp-based metastable excitation outperforms the plasma discharge across a wide range of beam flux values relevant for atom trap trace analysis (ATTA). Moreover, we do not observe significant degradation in lamp performance after over 160 h of operation. We find that lamp-based excitation is particularly advantageous at the smallest and largest beam fluxes tested, demonstrating the utility of this approach both for improving krypton ATTA and for enabling the detection of radioactive xenon isotopes using ATTA. Finally, we demonstrate an additional enhancement to lamp-based metastable excitation efficiency and stability by applying an external magnetic field.

Charles V. Shank, P. C. Becker, H. L. Fragnito +1 more

V. Lefèvre-Seguin, Michèle Leduc

Collisions between rare-gas atoms in the 3 P 2 metastable state and in the ground state were studied. The metastable atoms were created by a discharge and oriented by optical pumping, and pressure broadening of their magnetic-resonance curves was measured. For xenon, mixtures of even and odd isotopes were used, leading to a determination of the cross section for metastability-exchange collisions. For krypton the results are reported for the disorientation of the metastable state in the natural gas. In addition the disorientation cross section has been measured of the krypton metastable state through collisions with helium.