We performed a mapping observation of the Sunyaev-Zel'dovich effect toward a galaxy cluster, CL0016+16, at 43 GHz using a newly developed 6-beam receiver installed in the Nobeyama 45-m telescope. The temperature decrement of the CMB was measured to be δT*A = −0.49 ± 0.06 mK at the center of the cluster. Fitting the isothermal, spherical-symmetrical β -model to the observed temperature decrement distribution, the S-Z effect at the center is inferred to be δTRJ(0) = −1.0 ± 0.1 mK at the Rayleigh-Jeans limit. This suggests that the Hubble constant is H0{q0 = 0.5} = 67+16−11 km s−1 Mpc−1.

We briefly report the results of polarimetric observations of SiO emission from late-type stars taken with a millimeter polarimeter installed at the Nobeyama 45m telescope. We found that the SiO J = 2 − 1 emission in the v = 0 state from R Cas contains a highly linearly polarized component, followed by the detection of highly linearly polarized emission of the same transition from VY CMa (Shinnaga et al. 1999). The high polarization degree is a strong evidence that the v = 0 emission originates from maser action. We found out that, not only a peculiar supergiant star, but also a Mira variable star is associated with the SiO v = 0 maser.

We present 6″ (460 pc at a distance of 9.6 Mpc) resolution CO(J=1−0) map of the central region of the grand-design spiral galaxy M51 and very preliminary 4″ (180pc) resolution CO(J=1−0) map of the arm regions, using the Nobeyama Millimeter Array (NMA). The central 3kpc region (1') was mapped with a velocity resolution of 20km/s, and the rest with 10km/s.

We have observed the 12CO (Ishizuki et al 1990) and 13CO emission of the central 65″ region of the galaxy IC342 at the high resolutions of 2.4″ for 12CO and 5.1″×4.2″ for 13CO using the Nobeyama Millimeter Array. The integrated intensities of 12CO and 13CO emission are shown in Fig.1 and 2, respectively.