  High-quality (001)-oriented (pseudo-cubic notation) ferromagnetic YTiO$_3$
thin films were epitaxially synthesized in a layer-by-layer way by pulsed laser
deposition. Structural, magnetic and electronic properties were characterized
by reflection-high-energy-electron-diffraction, X-ray diffraction, vibrating
sample magnetometry, and element-resolved resonant soft X-ray absorption
spectroscopy. To reveal ferromagnetism of the constituent titanium ions, X-ray
magnetic circular dichroism spectroscopy was carried out using four detection
modes probing complimentary spatial scale, which overcomes a challenge of
probing ferromagnetic titanium with pure Ti3+(3d$^1$). Our work provides a
pathway to distinguish between the roles of titanium and A-site magnetic
rare-earth cations in determining the magnetism in rare-earth titanates thin
films and heterostructures.
