Extraction of precise Gamow-Teller quenching value Q, Landau-Migdal parameter g'NΔ and pion condensation

Measurements on Zr-90(p, n) and Zr-90(n, p) reactions at 300 MeV were made and reliable Sbeta- and Sbeta+ values are successfully extracted. A Gamow-Teller quenching factor (Q) in terms of the spin sum rule of Sbeta- - Sbeta+ = 3(N - Z) is derived as Q = 0.89 +/- 0.04(MDA) +/- 0.04(IVSM) apart from the systematic uncertainty of Delta sigma(GT) < 15%. The Landau-Migdal (LM) parameters representing a short-range correlation in an isospin-spin channel are deduced to be g'(NN) = 0.60 +/- 0.02 and g'(N Delta) = 0.24 +/- 0.10 with the Chew-Low coupling constant f(Delta)/f(pi) = 2. The critical density of the pion condensation is estimated to be p - 2po which can be easily realized in the neutron stars. Recent observation of the surface temperature of the neutron star 3C58 supports the picnic cooling mechanism and consequently manifestation of the pion condensation in neutron starts.