Abstract
A combined photometric and polarimetric analysis of OB stars known from two searches of OB stars in the Puppis region resulted in the identification of a new OB association located at a distance of 2.6 kpc from the Sun and with a main concentration at l=249fdg 3, b=-4fdg 6. There is another young group at a greater distance (4.4 kpc) that partially overlaps the first one on the (l,b) plane. The polarization efficiency of the dust towards the association is very low (1.25). The parameters of the ISM in the central region of the association are P_V=1.21± 0.18(%) and theta_V=140fdg 2± 3fdg 3; the dust grains are of normal size, similar to the mean for the ISM (0.55 μm). We discuss the location of both groups and propose the OB association as part of the local arm, while the other group would be part of the Perseus arm, according to the four-arm model of Hou & Han.
