Detection of a single Ba2+ ion in many tons of xenon is a formidable technological challenge. The difficulty is exacerbated by the fact that Ba2+, the expected final state in double beta decay of gaseous 136Xe, has no visible-accessible optical transitions to use for atomic fluorescence spectroscopy. To overcome this challenge, the NEXT collaboration is developing a method of tagging...
Our group in the nEXO collaboration is developing a cryogenic method for Ba daughter tagging in neutrinoless double beta decay in liquid 136Xe. The principle is to capture the Ba daughter from liquid xenon by trapping it in a solid xenon layer on a cryogenic probe window and then scanning the layer with a laser for 1 Ba atom/ion or 0 Ba atom/ion. We can now image single Ba atoms in a solid...
Radio frequency (RF) carpets are ion beam transport devices that have become ubiquitous in nuclear science. They first appeared in large volume gas cells where they allowed the efficient transport at pressures around 100 mbar of thermalized radioactive ions produced in-flight. Then, more recently, they started to be used at lower pressures, in the 1-10 mbar range, to dissociate molecular...
