Early spectral evolution of Nova Sgr 2004 (V5114 Sgr)

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...

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Life after eruption - II. The eclipsing old nova V728 Scorpii

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...

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The hunt for old novae

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...

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Fotometria target BIS catalog del 04 Mar 2013 alle 18:39

Serata con ottime condizioni meteo.
Effettuate riprese sulle Carbon Star BIS007, BIS184, BIS198, BIS196.
Sono stati ripresi anche i campi Landolt necessari per la calibrazione per gli indici di colore, e per la misura in fotometria assoluta.
Nei prossimi giorni si avranno i risultati delle misure in fotometria assoluta e differenziale.

Raniero Albanesi