emsao is an IRAF task in the rvsao package which finds emission lines, computes redshifts for each identified line, and combines them into a single radial velocity. The results may be graphically displayed and/or printed in several formats.


emsao spectra

Procedure (flowchart)


Cursor Commands


PASP Paper on EMSAO and RVSAO package [ADS Abstract] [local abstract]

"RVSAO 2.0: Digital Redshifts and Radial Velocities" Michael J. Kurtz and Douglas J. Mink, 1998, PASP, v. 110, pp. 934-977.

ADASS Paper on EMSAO [abstract] [full text]

"EMSAO: Radial Velocities from Emission Lines in Spectra"
D.J. Mink and W.F. Wyatt (1995), in Astronomical Data Analysis Software and Systems IV, ASP Conf. Ser., Vol. 77, eds. R.A. Shaw, H.E. Payne, and J.J.E. Hayes, p. 496-499.

Last updated September 20, 2019 by Jessica Mink

Telescope Data Center [rvsao] [xcsao] [emsao] [sumspec] [linespec]