Emission-line galaxies are important targets for understanding the
chemical evolution of galaxies in the universe. Deep, narrow-band
imaging surveys allow to detect and study the flux and the equivalent
widths (EW) of the emission line studied. The present work has been
developed within the context of the OTELO project, an emission line
survey using the Tunable Filters (TF) of OSIRIS, the first generation
instrument on the GTC 10.4m telescope located in La Palma, Spain, that
will observe through selected atmospheric windows relatively free of sky
emission lines. With a total survey...
Star formation rate (SFR), metallicity and stellar mass are within the
important parameters of star—forming galaxies that characterize their
formation and evolution. They are known to be related to each other at
low and high redshift in the mass—metallicity, mass—SFR, and
metallicity—SFR relations. In this work we demonstrate the existence of
a plane in the 3D space defined by the axes SFR [log(SFR)(M_sun yr^-1)],
gas metallicity [12+log(O/H)], and stellar mass [log(M_star/M_sun)] of
star-forming galaxies. We used star—forming galaxies from the "main
galaxy sample" of the Sloan...
We present optical and near-infrared spectral evolution of the Galactic
nova V5114 Sgr (2004) during few months after the outburst. We use
multi-band photometry and line intensities derived from spectroscopy to
put constrains on the distance and the physical conditions of the ejecta
of V5114 Sgr. The nova showed a fast decline (t_2 \simeq 11 days) and
spectral features of FeII spectroscopic class. It reached M_V = 8.7 \pm
0.2 mag at maximum light, from which we derive a distance of 7700 \pm
700 kpc and a distance from the galactic plane of about 800 pc. Hydrogen
and Oxygen mass of...
The old nova V728 Sco has been recently recovered via photometric and
spectroscopic observations, 150 yr after the nova eruption. The spectral
properties pointed to a high-inclination system with a comparatively low
mass-transfer rate. In this paper, we show that the object is an
eclipsing system with an orbital period of 3.32 h. It has enhanced
long-term variability that can be interpreted as `stunted’
dwarf-nova-type outbursts. Using the ingress and egress times of the
eclipsed components we calculate the radius of the central object. The
latter turns out to be significantly...
We inform on the progress of our on-going project to identify and
classify old classical novae, using deep UBVR photometry and subsequent
spectroscopy for a proper candidate confirmation, and time-resolved
observations in order to find the orbital period and other physical
properties of the identified old novae. This way, we have already
increased the number of confirmed southern and equatorial post-novae
from 33 to 50, and determined new orbital periods of eight objects. As
an example, we summarise the results on V728 Sco (Nova Sco 1862) which
we found to be an eclipsing system...
