title: Search for interstellar superheavy hydrogen.
abstract: Models for fundamental physical interactions allow for the existence of stable or nearly stable elementary particles much heavier than the proton. Stellar spectra were searched for a positively charged superheavy particle, X(+), which, with a bound electron, should appear as apparently superheavy neutral hydrogen in the interstellar medium. An upper limit for the abundance of X relative to normal hydrogen in the line of sight toward the bright star gamma Cassiopeiae is 2 x 10(-8).
authors.forename: M
authors.initials: M
authors.lastname: Jura
authors.forename: D G
authors.initials: DG
authors.lastname: York