6-m telescope observations of three dwarf spheroidal galaxies with very low surface brightness
Abstract
Dwarf spheroidal galaxies (dSphs) are mostly investigated in the Local Group. DSphs are difficult targets for observations because of their small size and very low surface brightness. Here we measure spectroscopic and photometric parameters of three candidates for isolated dSphs, KKH 65 = BTS23, KK 180, and KK 227, outside the Local Group. The galaxies are found to be of low metallicity and low velocity dispersion. They are among the lowest surface brightness objects in the Local Universe. According to the measured radial velocities, metallicities, and structural and photometric parameters, KKH 65 and KK 227 are representatives of the ultra-diffuse quenched galaxies. KKH 65 and KK 227 belong to the outer parts of the groups NGC 3414 and NGC 5371, respectively. KK 180 is located in the Virgo cluster infall region.
Appendices are available in electronic form at http://www.aanda.org- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- September 2015
- DOI:
- 10.1051/0004-6361/201526947
- arXiv:
- arXiv:1509.02784
- Bibcode:
- 2015A&A...581A..82M
- Keywords:
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- galaxies: dwarf;
- galaxies: distances and redshifts;
- galaxies: fundamental parameters;
- galaxies: photometry;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- 4 pages, 3 figures, 3 tables, 3 Appendices with 5 figures and 3 tables