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We investigated the star formation activities in the AFGL 333 region, which is in the vicinity of the W4 expanding bubble, by conducting NH 3 (1,1), (2,2), and (3,3) mapping observations with the 45 m Nobeyama Radio Telescope at an angular resolution of 75 ′′ . The morphology of the NH 3 (1,1) map shows a bow-shape structure with the size of 2.0 × 0.6 pc as seen in the dust continuum. At the interface between the W4 bubble and the dense NH 3 cloud, the compact HII region G 134.2+0.8, associated with IRAS 02245+6115, is located. Interestingly, just north and south of G 134.2+0.8 we found NH 3 emission exhibiting large velocity widths of ∼ 2.8 km s −1 , compared to 1.8 km s −1 at the other positions. As the possibility of mechanical energy injection through the activity of YSO(s) is low, we considered the origin of the large turbulent gas motion as indication of interaction between the compact HII region and the periphery of the dense molecular cloud. We also found expanding motion of the CO emission associated with G 134.2+0.8. The overall structure of the AFGL 333-Ridge might have been formed by the expanding bubble of W4. However, the small velocity widths observed west of IRAS 02245+6115, around the center of the dense molecular cloud, suggest that interaction with the compact HII region is limited. Therefore the YSOs (dominantly Class 0/I) in the core of the AFGL 333-Ridge dense molecular cloud most likely formed in quiescent mode. As has been previously suggested for the large scale star formation in the W3 giant molecular cloud, our results show an apparent coexistence of induced and quiescent star formation in this region. It appears that star formation in the AFGL 333 region has proceeded without significant external triggers, but accompanying stellar feedback environment.

We mapped the (1,1), (2,2), and (3,3) lines of NH 3 toward the molecular cloud associated with the Monkey Head Nebula (MHN) with a 1. 6 angular resolution using a Kashima 34 m telescope operated by the National Institute of Information and Communications Technology (NICT). The kinetic temperature of the molecular gas is 15-30 K in the eastern part and 30-50 K in the western part. The warmer gas is confined to a small region close to the compact H ii region S252A. The cooler gas is extended over the cloud even near the extended H ii region, the MHN. We made radio continuum observations at 8.4 GHz using the Yamaguchi 32 m radio telescope. The resultant map shows no significant extension from the Hα image. This means that the molecular cloud is less affected by the MHN, suggesting that the molecular cloud did not form by the expanding shock of the MHN. Although the spatial distribution of the Wide-field Infrared Survey Explorer and Two Micron All Sky Survey point sources suggests that triggered low-and intermediate-mass star formation took place locally around S252A, but the exciting star associated with it should be formed spontaneously in the molecular cloud.

We present distance measurement of the semiregular variable RX Bootis (RX Boo) with its annual parallax. Using the unique dual-beam system of the VLBI Exploration of Radio Astrometry (VERA) telescope, we conducted astrometric observations of a water maser spot accompanying RX Boo referred to the quasar J1419+2706 separated by 1 • .69 from RX Boo. We have measured the annual parallax of RX Boo to be 7.31 ± 0.50 mas, corresponding to a distance of 136 +10 −9 pc, from the one-year monitoring observation data of one maser spot at V LSR = 3.2 km s −1 . The distance itself is consistent with the one obtained with Hipparcos. The distance uncertainty is reduced by a factor of two, allowing us to determine the stellar properties more accurately. Using our distance, we discuss the location of RX Boo in various sequences of Period-Luminosity (PL) relations. We found RX Boo is located in the Mira sequence of PL relation. In addition, we calculated the radius of photosphere and the mass limitation of RX Boo and discussed its evolutionary status.