The structure and kinematics of the intergalkactic southwest in the M81 group.

October 1988 • 1988MNRAS.234..957A

Authors • Appleton, P. N. • van der Hulst, J. M.

Abstract • Neutral hydrogen observations made with a resolution of 1x1 arcmin^2^ have revealed considerable structure in the SW cloud region of the M81 group. A neutral hydrogen filament of length more than 37 kpc lies between M81 and the dwarf spiral companion NGC 2976. The filament, which may be connected to M81, is composed of many individual clouds of H I. The filament twists at about two-thirds of the way along its length. The velocity field of the filament exhibits a constant gradient everywhere except in the region of the twist, where sharp changes of gradient are observed. Close to this discontinuity, there is a compact H I cloud which shows evidence for internal rotation in the opposite sense to the large-scale velocity gradient in the filament. It is likely that this compact cloud is a dwarf galaxy similar in nature to M81 dw B discovered in the extended M81 group by Lo & Sargent. Unlike this latter galaxy, however, the new object may have the same origin as the H I filament, which is probably tidally generated.

Links

• SIMBAD http://simbad.u-strasbg.fr/simbo.pl?bibcode=1988MNRAS.234..957A
• NED https://ned.ipac.caltech.edu/uri/NED::InRefcode/1988MNRAS.234..957A
• ELECTR http://dx.doi.org/10.1093/mnras/234.4.957
• GIF http://articles.adsabs.harvard.edu/full/1988MNRAS.234..957A
• ARTICLE http://articles.adsabs.harvard.edu/full/1988MNRAS.234..957A?defaultprint=YES