Disentangling CMB $μ$ and $y$ spectral distortions from foregrounds with poorly defined spectral shapes

We have presented a new approach to separate small spectral $μ$ and $y$ distortions of the CMB from foreground components with poorly defined spectral shapes. Our linear method, called the Least Response Method (LRM), is based on the idea of simultaneously minimizing the response to all possible foregrounds and photon noise while maintaining a constant response to the useful signal. We compared our approach with the mILC method, which is a modification of the Internal Linear Combination previously used for CMB anisotropy maps, and proved the advantages of LRM. In addition, we found the optimal temperature of the telescope optical system for any experiments related to the study of the CMB $μ$ distortions.