The particle spectra and Hanbury-Brown Twiss (HBT) radius of Au+Au collisions at RHIC energy are investigated by a hydrodynamical expanding source with both shear and bulk viscosities (ζ).With a large width of the ratio of ζ to entropy density s,both the particle transverse momentum spectra and the ratio Rout/Rside of HBT radii in the direction of the total transverse momentum of detected two particles (Rout) and perpendicular to both this direction and the beam direction (Rside) become a little steeper.
