The Araucaria Project. The distance to the Sculptor group galaxy NGC 7793 from near-infrared photometry of Cepheid variables
1 Nicolaus Copernicus Astronomical Center of the Polish Academy of Sciences, Warsaw, Poland
2 Astronomical Observatory of the University of Warsaw, Warsaw, Poland
3 Universidad de Concepción, Departamento de Astronomia, Concepción, Chile
4 Millennium Institute of Astrophysics, Santiago, Chile
Published online: 8 September 2017
We performed deep near-infrared J and K photometry of a field in the Sculptor Group spiral galaxy NGC 7793 using ESO VLT and HAWK-I instrument. We produced a sample of 14 Cepheids whose locations and periods of pulsation were known from our previous paper on distance determination to this galaxy based on V and I bands. We determined mean J and K magnitudes based on measurements from two nights and produced period-luminosity relations for both filters. Using those near-infrared dependencies together with relations for bands V and I obtained before, we were able to obtain true distance modulus for NGC 7793. We also calculated the mean reddening affecting our Cepheids.
© The Authors, published by EDP Sciences, 2017
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