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arXiv · 1110.6111

Pitch angles of distant spiral galaxies

S. S. Savchenko·V. P. Reshetnikov
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Abstract

We have studied the pitch angles of spiral arms for 31 distant galaxies at z~0.7 from three Hubble Deep Fields (HDF-N, HDF-S, HUDF). Using the pitch angle - rotation velocity relation calibrated from nearby galaxies, we have estimated the rotation velocities of galaxies from the deep fields. These estimates have a low accuracy (~50 km/s), but they allow low-mass and giant galaxies to be distinguished. The Tully-Fisher relation constructed using our velocity estimates shows satisfactory agreement with the actually observed relations for distant galaxies and provides evidence for the luminosity evolution of spiral galaxies.

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S. S. Savchenko, V. P. Reshetnikov. 2011-10-27. Pitch angles of distant spiral galaxies. https://doi.org/10.1134/s1063773711120097

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