  We have successfully loaded a magneto-optic trap for Yb atoms from a thermal
source without the use of a Zeeman slower. The source is placed close to the
trapping region so that it provides a large flux of atoms that can be cooled
and captured. The atoms are cooled on the ${^1S_0} \leftrightarrow {^1P_1}$
transition at 398.8 nm. We have loaded all seven stable isotopes of Yb into the
trap. For the most abundant isotope ($^{174}$Yb), we load more than $10^7$
atoms into the trap within 1 s. For the rarest isotope ($^{168}$Yb) with a
natural abundance of only 0.13%, we still load about $4 \times 10^5$ atoms into
the trap. We find that the trap population is maximized near a detuning of
$-1.5\Gamma$ and field gradient of 75 G/cm.

Atomic Physics