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We studied the polarization properties of Cygnus X-1 in both hard and softspectral states with Imaging X-ray Polarimetry Explorer (IXPE) observations.The polarization degree is $\sim4$%, and $\sim 2.6-2.8$% in the hard and softstates, respectively. The polarization angle is observed along the jet axis andremains the same in both states. Energy-dependent analysis revealed anincreasing polarization with the energy. The observed polarization rules outthe lamp-post corona and prefers a conical corona if the coronal geometryremains the same in the hard and soft states. The disk is not detected in thehard state but is found in the soft state in the IXPE spectra. The spectralanalysis revealed that the disk emission contributes $\sim 20$% of the totalemission in the soft state. The scattering of the seed photons inside thecorona is likely to reduce the polarization. This could explain the differentpolarization in different spectral states. Additionally, if the diskpolarization is perpendicular to that of the corona, it could also reduce thepolarization in the soft state.

X-ray Polarization changes with the State Transition in Cygnus X--1