Research Note

On high-latitude interstellar polarization toward the local spiral

Tuorla Observatory, Department of Physics and Astronomy, University of Turku, Väisäläntie 20, 21500 Piikkiö, Finland
e-mail: pekkatee@utu.fi

Received: 19 November 2015
Accepted: 14 January 2016

Abstract

Aims. The interstellar polarization in the northern high-latitude sky is low and rather smooth in the local spiral (LS) longitude range 60° < l < 240°, except for an extension of aligned higher polarization within 120° < l < 180° up to b ≈ 50°. We compare this view with results from other indicators of interstellar matter.

Methods. Some indicators of dust are sensitive to diffuse matter on large scales, others provide information on clumpy structures. We describe results that are mainly from surveys of dark and molecular clouds in the LS longitude range at high latitudes.

Results. The structured feature in the polarization map for the LS region corresponds to known dark cloud complexes. These extensions to higher latitudes (and some other dust indicators) may signal the presence of more dust in some form (like compact cold clouds) than is suggested by regular low interstellar polarization.