Unified Description of Meson and Baryon Masses and the Charmed Particles

A unified description of masses of mesons and baryons is proposed which is reduced to the quadratic and linear mass formula for very small and large hadron masses, respectively. Usual linear mass relations are applied to the quantity defined by M= √<m^2+M_0^26gt; -m_0, where m is the mass of observed hadron and m_0 is a constant. Then the symmetry breaking parameters such as δm_λ^2=m_K^2-m_π^2 for mesons and Δm_λ=(m_g-m_Δ)/3 for baryons can be related approximately through a scale mass m_0 as δm_λ^2 bcong 2m_0Δm_λ, where m_0~1 GeV. The Okubo-Gell-Mann relation for the octet baryons and the equal-spacing law for the decuplet baryons hold extremely well when m_0~1 GeV is taken. In the quartet model, we assume that mass breaking parameters due to charm Δm_c are given by taking Δm_c-Δm_λ (as the alternative of Δm_c/Δm_λ) common to all multiplets. The masses of vector, pseudoscalar and tensor mesons are calculated and compared with experiments on the heavy new particles.