Abstract
Several formulas for the eigenvalues $$\lambda _j$$
λ
j
of the Weyl transforms $$W_\sigma $$
W
σ
of symbols $$\sigma $$
σ
given by radially symmetric distributions are derived. These yield criteria for the boundedness and the compactness, respectively, of the pseudo-differential operators $$W_\sigma .$$
W
σ
.
We investigate some examples by analyzing the asymptotic behavior of $$\lambda _j$$
λ
j
for $$j\rightarrow \infty $$
j
→
∞
.