X-ray magnetic circular dichroism (XMCD) is a well-established technique for investigating magnetism. I will present experimental and computational XMCD spectra of several popular altermagnets. The
origin and symmetry aspects of the phenomenon will be discussed as well as its potential application
for determination of the direction of the Neel vector and mapping of altermagnetic domains.

In the second part of the talk, I will discuss another popular x-ray tool, resonant inelastic x-ray scattering (RIXS), and its combination with circularly polarized x-rays. Unlike XMCD, the RIXS-CD in magnetic materials has just started to attract experimental interest and its theoretical foundations are being established. Interestingly, the symmetry properties of RIXS-CD are rather different from XMCD with interesting consequences such as finite CD in the paramagnetic states in certain symmetries.