Let X be a re
exive separable Banach space and pB be the set of p-Bessel sequences in X for X. We
show that pB is a non-commutative unital Banach algebra isometrically isomorphic to B(X). Also, we
classify p-Bessel sequences for X in terms of dierent kind of operators in B(X). Using operator theory
tools, we investigate the geometry of p-Bessel sequences. Also, we show that the set of all q-Riesz bases
for X is a topological group.