  A stacked-target of natural lanthanum foils (99.9119% $^{139}$La) was
irradiated using a 60 MeV proton beam at the LBNL 88-Inch Cyclotron.
$^{139}$La(p,x) cross sections are reported between 35-60 MeV for nine
radionuclides. The primary motivation for this measurement was the need to
quantify the production of $^{134}$Ce. As a positron-emitting analogue of the
promising medical radionuclide $^{225}$Ac, $^{134}$Ce is desirable for in vivo
applications of bio-distribution assays for this emerging radio-pharmaceutical.
The results of this measurement were compared to the nuclear model codes TALYS,
EMPIRE and ALICE (using default parameters), which showed significant deviation
from the measured values.
