The Analysis of the Barred Galaxy NGC 6701

Abstract

Images: 1.5m Spanish telescope in Calar Alto, Thomson blue coated 1024×1024 CCD, 0.31″pixel−1. Exposition times of 1800, 1500 and 1200 (BV R) and 2000 seconds (Hα and continuum) were used. Seeing FWHM = 1″. Spectra for NGC 6701: 3.5m telescope, PA=25°, 115°, 145° and 175° (Hβ region), 2.2m telescope, PA=25° and 115° (Hα region). The spectrum along the companion galaxy (PA=0°) was also obtained with the 2.2m telescope.In Figure 1a the bar is clearly seen, extending almost all along an axis very close to the disk minor axis. The spiral arms emerge from the bar, with the arm to the north being the more luminous one. The main spiral structure delineates a pseudo-outer ring when the arms close together. The prominent bar structure has a diamond-like aspect (22″×l2″) mainly traced by the two more intense sides. The zones just immediately inside these linear paths are notably fainter, as expected for a region in which the presence of dust is important. The ellipse fitting to the µB=23.5 mag arcsec−2 isophote gives a = 13, b = 12 and PA = 25°. Total (corrected) magnitudes are mB = 12.96(12.65), mV=12.44(12.20) and mI=11.64(11.46).