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Spiral structure of the giant galaxy UGC 2885: Hα kinematics

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Abstract

The TAURUS I imaging Fabry-Perot spectrometer is used to map the velocity field of the giant spiral galaxy UGC 2885 in H-alpha emission at 5-arcsec resolution. Ripples in the velocity field around the minor axis indicate radial flows across the spiral arms. The radial flow speeds in the plane of the disk show 50-70 km/s peak-to-peak variation, suggesting that a strong density wave is present in the underlying stellar disk. Such high speeds may alternatively be a natural consequence of the open arm spiral patterns. Strong density waves may naturally occur in large spiral galaxies or in spiral galaxies as massive as UGC 2885.
1993ApJ...406..457C
1993ApJ...406..457C
1993ApJ...406..457C
1993ApJ...406..457C
1993ApJ...406..457C
1993ApJ...406..457C
1993ApJ...406..457C
1993ApJ...406..457C
1993ApJ...406..457C
1993ApJ...406..457C
1993ApJ...406..457C
1993ApJ...406..457C
1993ApJ...406..457C
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