Aims. In this work we present chromospheric activity indices, kinematics, radial-velocities, and rotational velocities for more than 850 FGK-type dwarfs and subgiant stars in the southern hemisphere and test how best to calibrate and measure S -indices from echelle spectra. Methods. We measured our parameters using the high-resolution and high-S /N FEROS echelle spectra acquired for this purpose. Results. We confirm the bimodal distribution of chromospheric activities for such stars and highlight the role that the more active K-dwarfs play in biasing the number of active stars. We show that the age-activity relationship does appear to continue to ages older than the Sun if we simply compare main sequence stars and subgiant stars with an offset of around 2.5 Gyr between the peaks of both distributions. Also we show evidence of an increased spin-down timescale for cool K dwarfs compared with earlier F and G type stars. We highlight that activities drawn from low-resolution spectra (R < 2500) significantly increase the rms scatter when calibrating onto common systems of measurements like the Mt. Wilson system. Also we show that older and widely used catalogues of activities in the south appear to be offset compared to more recent works at the ∼0.1 dex level in log R HK through calibrator drift. In addition, we show how kinematics can be used to preselect inactive stars for future planet search projects. We see the well known trend between projected rotational velocity and activity, however we also find a correlation between kinematic space velocity and chromospheric activity. It appears that after the Vaughan-Preston gap there is a quick step function in the kinematic space motion towards a significantly broader spread in velocities. We speculate on reasons for this correlation and provide some model scenarios to describe the bimodal activity distribution through magnetic saturation, residual low level gas accretion, or accretion by the star of planets or planetesimals. Finally, we provide a new empirical measurement for the disk-heating law, using the latest age-activity relationships to reconstruct the age-velocity distribution for local disk stars. We find a value of 0.337 ± 0.045 for the exponent of this power law (i.e. σ tot ∝ t 0.337 ), in excellent agreement with those found using isochrone fitting methods and with theoretical disk-heating models.

We use early-time photometry and spectroscopy of 12 Type II plateau supernovae (SNe IIP) to derive their distances using the expanding photosphere method (EPM). We perform this study using two sets of Type II supernova (SN II) atmosphere models, three filter subsets ({BV }, {BV I}, {V I}), and two methods for the host-galaxy extinction, which leads to 12 Hubble diagrams. We find that systematic differences in the atmosphere models lead to ∼ 50% differences in the EPM distances and to a value of H 0 between 52 and 101 km s −1 Mpc −1 . Using the {V I} filter subset we obtain the lowest dispersion in the Hubble diagram, σ µ = 0.32 mag. We also apply the EPM analysis to the well-observed SN IIP 1999em. With the {V I} filter subset we derive a distance ranging from 9.3 ± 0.5 Mpc to 13.9 ± 1.4 Mpc depending on the atmosphere model employed.-2on their light curves into Type IIP (plateau) and Type IIL (linear) (e.g., Patat et al. 1994). The former present a nearly constant optical luminosity during the photospheric phase (∼ 100 days after explosion), while the latter show a slow decline in luminosity during that phase. However, there are some SN II events, such as the SN 1987A, that show peculiar photometric properties. Also, studies of SN II spectra have revealed the existence of a subclass, characterized by the presence of narrow spectral lines, called SNe IIn (Schlegel 1990; Filippenko 1991a,b), which are most likely originated from the interaction of the SN ejecta with pre-existing circumstellar material; see Filippenko (1997) for a general review of SN spectra.Due to their high intrinsic luminosities, SNe II have great potential as extragalactic distance indicators. To date, several methods have been proposed to derive distances to SNe II, but two are the most commonly used: the expanding photosphere method (EPM) (Kirshner & Kwan 1974) and the standardized candle method (SCM) (Hamuy & Pinto 2002). The former is a geometrical technique that relates the photospheric radius and the angular radius of a SN in order to derive its distance, and has been applied to several SNe to derive the Hubble constant (e.g., Schmidt et al. 1992). The EPM is independent of the extragalactic distance ladder, and therefore does not need any external calibration. The SCM is based on the observed relation between expansion velocity and luminosity of SNe IIP. Recently, this method has been applied to a sample of high-redshift SNe (Nugent et al. 2006). Other methods have also been used to determine distances to SNe II, such as the spectral-fitting expanding atmosphere method (SEAM) ( Baron et al. 2004) and the plateau-tail relation proposed by Nadyozhin (2003).In this work we apply the EPM using early spectroscopy and photometry of 12 SNe IIP in order to derive their distances. We apply the method using two sets of SN II atmosphere models (Eastman et al. 1996;Dessart & Hillier 2005a), three filter subsets ({BV }, {BV I}, {V I}), and two methods for the host-galaxy extinction. The different combinations lead to 12 Hubble diagrams. Section 2 of...

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Context. More than 50 exoplanets have been found around giant stars, revealing different properties when compared to planets orbiting solar-type stars. In particular, they are super-Jupiters and are not found orbiting interior to ∼0.5 AU. Aims. We are conducting a radial velocity study of a sample of 166 giant stars aimed at studying the population of close-in planets orbiting giant stars and how their orbital and physical properties are influenced by the post-MS evolution of the host star. Methods. We have collected multiepoch spectra for all of the targets in our sample. We have computed precision radial velocities from FECH/CHIRON and FEROS spectra, using the I 2 cell technique and the simultaneous calibration method, respectively. Results. We present the discovery of a massive planet around the giant star HIP 105854. The best Keplerian fit to the data leads to an orbital distance of 0.81 ± 0.03 AU, an eccentricity of 0.02 ± 0.03 and a projected mass of 8.2 ± 0.2 M J . With the addition of this new planet discovery, we performed a detailed analysis of the orbital properties and mass distribution of the planets orbiting giant stars. We show that there is an overabundance of planets around giant stars with a ∼ 0.5−0.9 AU, which might be attributed to tidal decay. Additionally, these planets are significantly more massive than those around MS and subgiant stars, suggesting that they grow via accretion either from the stellar wind or by mass transfer from the host star. Finally, we show that planets around evolved stars have lower orbital eccentricities than those orbiting solar-type stars, which suggests that they are either formed in different conditions or that their orbits are efficiently circularized by interactions with the host star.