Nova Oph 2009 (V2672 Oph) reached maximum brightness V= 11.35 on 2009 August 16.5. With observed t2(V) = 2.3 and t3(V) = 4.2 d decline times, it is one of the fastest known novae, being rivalled only by V1500 Cyg (1975) and V838 Her (1991) among classical novae, and U Sco among the recurrent ones. The line of sight to the nova passes within a few degrees of the Galactic Centre. The reddening of V2672 Oph is E(B−V) = 1.6 ± 0.1, and its distance d∼ 19 kpc places it on the other side of the Galactic Centre at a galactocentric distance larger than the solar one. The lack of an infrared counterpart for the progenitor excludes the donor star from being a cool giant like in RS Oph or T CrB. With close similarity to U Sco, V2672 Oph displayed a photometric plateau phase, a He/N spectrum classification, extreme expansion velocities and triple peaked emission‐line profiles during advanced decline. The full width at zero intensity of Hα was 12 000 km s−1 at maximum, and declined linearly in time with a slope very similar to that observed in U Sco. The properties displayed by V2672 Oph lead us to infer a mass of its white dwarf close to the Chandrasekhar limit and a possible final fate as a Type Ia supernova. Morpho‐kinematical modelling of the evolution of the Hα profile suggests that the overall structure of the ejecta is that of a prolate system with polar blobs and an equatorial ring. The density in the prolate system appeared to decline faster than that in the other components. V2672 Oph is seen pole‐on, with an inclination of 0°± 6° and an expansion velocity of the polar blobs of 4800+900−800 km s−1. On the basis of its remarkable similarity to U Sco, we suspect this nova may be a recurrent. Given the southern declination, the faintness at maximum, the extremely rapid decline and its close proximity to the ecliptic, it is quite possible that previous outbursts of V2672 Oph have been missed.
Aims. The goal of our survey is to provide accurate and multi-epoch radial velocities, atmospheric parameters (T eff , log g and [M/H]), distances, and space velocities of faint red clump (RC) stars. Methods. We recorded high signal-to-noise (S /N ≥ 200) spectra of RC stars over the 4750-5950 Å range at a resolving power 5500. The target stars are distributed across the great circle of the celestial equator. Radial velocities were obtained via cross-correlation with IAU radial velocity standards. Atmospheric parameters were derived via χ 2 fit to a synthetic spectral library. A large number of RC stars from other surveys were re-observed to check the consistency of our results and the absence of offsets and trends. Results. A total of 245 RC stars were observed (60 of them with a second epoch observation separated in time by about three months), and the results are presented in an output catalog. None of them is already present in other surveys of RC stars. In addition to astrometric and photometric support data from external sources, the catalog provides radial velocities (accuracy σ(RV) = 1.3 km s −1 ), atmospheric parameters (σ(T eff ) = 88 K, σ(log g) = 0.38 dex and σ([M/H]) = 0.17 dex), spectro-photometric distances, (X, Y, Z) galacto-centric positions and (U, V, W) space velocities.
ESA's Gaia mission will collect low resolution spectroscopy in the optical range for ∼10 9 objects. Complete and up-to-date libraries of synthetic stellar spectra are needed to built algorithms aimed to automatically derive the classification and the parametrization of this huge amount of data. In addition, libraries of stellar spectra are one of the main ingredients of stellar population synthesis models, aiming to derive the properties of unresolved stellar populations from their integrated light. We present (a) the newly computed libraries of synthetic spectra built by the Gaia community, covering the whole optical range (300-1100 nm) at medium-high resolution of (0.3 nm) for stars spanning the most different types, from M to O, from Apeculiar to Emission lines to White Dwarfs, and (b) the implementation of those libraries in our SSP code (Tantalo in The Initial Mass Function 50 Years Later, 327:235 2005), exploring different stellar evolution models.
ESA's Gaia mission will collect low resolution spectroscopy in the optical range for ∼10 9 objects. Complete and up-to-date libraries of synthetic stellar spectra are needed to built algorithms aimed to automatically derive the classification and the parametrization of this huge amount of data. In addition, libraries of stellar spectra are one of the main ingredients of stellar population synthesis models, aiming to derive the properties of unresolved stellar populations from their integrated light. We present (a) the newly computed libraries of synthetic spectra built by the Gaia community, covering the whole optical range (300-1100 nm) at medium-high resolution of (0.3 nm) for stars spanning the most different types, from M to O, from Apeculiar to Emission lines to White Dwarfs, and (b) the implementation of those libraries in our SSP code (Tantalo in The Initial Mass Function 50 Years Later, 327:235 2005), exploring different stellar evolution models.
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