Free Access
Astron. Astrophys. Suppl. Ser.
Volume 140, Number 2, December I 1999
Page(s) 247 - 260
Published online 15 December 1999
DOI: 10.1051/aas:1999421

Astron. Astrophys. Suppl. Ser. 140, 247-260

On the automatic folding of optical rotation curves

D.F. Roscoe

Send offprint request: D.F. Roscoe

School of Mathematics, Sheffield University, Sheffield, S3 7RH, UK

Received June 7; accepted September 6, 1999


[Mathewson, Ford and Buchhorn (1992], MFB hereafter) published the unreduced data for the optical rotation curves of 967 southern sky spiral galaxies. Recognizing that accurate dynamical modelling of spiral galaxies required the availability of a large data-base of correspondingly accurately folded rotation curves, [Persic & Salucci (1995], PS hereafter) undertook to fold the MFB sample in an appropriately meticulous way; of the 967 folded rotation curves, 900 were judged by PS to be of moderate to excellent quality, whilst 67 were judged to be of poor quality and of very limited use for dynamical studies. The folding process used by PS was a time-consuming and labour-intensive one in which the quality of each fold was judged "by eye''.

Subsequently, MFB (1996) published the unreduced optical rotation curves for approximately another 1100 southern sky spirals and, undoubtedly, more will follow from various sources. For this reason, and because of the importance of having large numbers of accurately folded rotation curves for dynamical studies, we have developed the automatic folding algorithm described herein.

An uncompiled Fortran program (using NAG routines) and data files are available via˜ap1dfr. Download the text file "ReadMe'' and follow instructions.

Key words: methods: numerical -- galaxies: kinematics and dynamics

Copyright The European Southern Observatory (ESO)

Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.

Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.

Initial download of the metrics may take a while.