Interstellar polarization at high galactic latitudes from distant stars. VI. Extended polarization map and connection with the local spiral structure

We present new interstellar polarization measurements for 116 stars at high galactic latitudes. Our data show that Markkanen's cloud - the main polarization structure seen in the North Galactic Pole area (b > 75°) extendsfurther towards lower latitudes. Especially, we have found a new dust formation in the area 35° 0 m .23. Polarization vectors in this cloud are very well aligned along the direction of l = 50°. On the IRAS 100 micron map this dust structure shows up as a bright emission area. We discuss the new polarization map extending from circumpolar to lower latitudes and point out features which suggest that Markkanen's cloud may be a part of the dust lane in the inner edge of the local spiral or spur.