15677079
Planetary companion candidates around the K giant stars 42 Draconis and HD 139 357
Context. For the past 3 years we have been monitoring 62 K giant stars using precise stellar radial velocity (RV) measurements with the 2 m Alfred Jensch Telescope of the Thuringer Landessternwarte Tautenburg ( TLS ). Aims. To probe the dependence of planet formation on stellar mass by finding planets around intermediate-mass giant stars. Methods. We present high accuracy RV measurements of the K1.5 III star 42 Dra and the K4 III star HD 139357. The wavelength reference for the RV measurements was provided by an iodine absorption cell placed in the optical path of the spectrograph. Results. Our measurements reveal that the time series of the radial velocity of 42 Dra shows a periodic variation of 479.1 days with a semiamplitude of K  = 112.5 m s -1 . An orbital solution yields a mass function of $f(m)$ = (5.29 ± 0.62) $\times$ 10 -8  solar masses ($M_{\odot}$) and an eccentricity of e  = 0.38  ±  0.06. From our template spectra, taken without the iodine cell, we determine a metallicity of -0.46  ±  0.04 dex and a stellar mass of 0.98 ± 0.06 $M_{\odot}$ for this star. HD 139 357 shows periodic RV variations of 1125.7 days with a semiamplitude K  = 159.9 m s -1 . An orbital solution yields an eccentricity, e = 0.10 ± 0.02 and mass function, $f(m)$ = (4.79 ± 0.57) $\times$ 10 -7  $M_{\odot}$. An iron abundance of -0.13 ± 0.04 dex is obtained, and a stellar mass of 1.31 ± 0.24 $M_{\odot}$ for the parent star is derived. An analysis of the HIPPARCOS photometry as well as our H α core flux measurements reveal no variability with the radial velocity period. Keplerian motion is the most likely explanation for the observed radial velocity variations for these stars. Conclusions. The K giant stars 42 Dra and HD 139 357 host extrasolar planets with “minimum masses” of 3.88 ± 0.85 Jupiter masses $M_{\mathrm{Jup}}$ and 9.76 ± 2.15 $M_{\mathrm{Jup}}$, respectively.
119184639
Transiting exoplanets from the CoRoT space mission XIV. CoRoT-11b: a transiting massive "hot-Jupiter" in a prograde orbit around a rapidly rotating F-type star
The CoRoT  exoplanet science team announces the discovery of CoRoT-11b, a fairly massive hot-Jupiter transiting a V  = 12.9 mag F6 dwarf star ( M ∗  = 1.27 ± 0.05  M ⊙ , R ∗  = 1.37 ± 0.03  R ⊙ , T eff  = 6440 ± 120 K), with an orbital period of P  = 2.994329 ± 0.000011 days and semi-major axis a  = 0.0436 ± 0.005 AU. The detection of part of the radial velocity anomaly caused by the Rossiter-McLaughlin effect shows that the transit-like events detected by CoRoT  are caused by a planet-sized transiting object in a prograde orbit. The relatively high projected rotational velocity of the star ( v sin i ⋆  = 40 ± 5 km s -1 ) places CoRoT-11 among the most rapidly rotating planet host stars discovered so far. With a planetary mass of M p   = 2.33 ± 0.34  M Jup  and radius R p   = 1.43 ± 0.03  R Jup , the resulting mean density of CoRoT-11b ( ρ p  = 0.99 ± 0.15 g/cm 3 ) can be explained with a model for an inflated hydrogen-planet with a solar composition and a high level of energy dissipation in its interior.
85540506
Oscillations in Procyon A First results from a multi-site campaign
Procyon A is a bright F5IV star in a binary system. Although the distance, mass and angular diameter of this star are all known with high precision, the exact evolutionary state is still unclear. Evolutionary tracks with different ages and different mass fractions of hydrogen in the core pass, within the errors, through the observed position of Procyon A in the Hertzsprung-Russell diagram. For more than15 years several different groups have studied the solar-like oscillations in Procyon A to determine its evolutionary state. Although several studies independently detected power excess in the periodogram, there is no agreement on the actual oscillation frequencies yet. This is probably due to either insufficient high-quality data (i.e., aliasing) or due to intrinsic properties of the star (i.e., short mode lifetimes). Now a spectroscopic multi-site campaign using 10 telescopes world-wide (minimizing aliasing effects) with a total time span of nearly 4 weeks (increase the frequency resolution) is performed to identify frequencies in this star and finally determine its properties and evolutionary state.
55685116
A substellar component orbiting the F-star 30 Arietis B
Context. Most current radial velocity planet search programs have concentrated on stars of one solar mass. Our knowledge on the frequency of giant planets and brown dwarf companions to more massive stars is thus rather limited. In the case of solar-like stars, the frequency of short-period brown dwarf companions and very massive planets seems to be low. Aims. Here we present evidence for a substellar companion to 30 Ari B, an F-star of 1.16 ± 0.04 $M_\odot$ that is a member of a hierarchical triple system. Methods. The companion was detected by means of precise radial velocity measurements using the 2-m Alfred-Jensch telescope and its echelle spectrograph. An iodine absorption cell provided the wavelength reference for precise stellar radial velocity measurements. Results. We analyzed our radial velocity measurements and derived an orbit to the companion with period, P = 335.1 ± 2.5 days, eccentricity e = 0.289 ± 0.092, and mass function $f(m)$ = (6.1 ± 1.7)$\times$10 -7 $M_\odot$. Conclusions. We conclude that the radial velocity variations of 30 Ari B are due to a companion with m  sin  i of 9.88 ± 0.94 $M_{\mathrm{Jup}}$ that is either a massive planet or a brown dwarf. The object thus belongs to the rare class of massive planets and brown dwarfs orbiting main- sequence stars.
55752588
Searching for nuclear stellar discs in simulations of star cluster mergers
The nuclei of galaxies often host small stellar discs with scalelengths of a few tens of parsecs and luminosities up to 107 L�. To investigate the formation and properties of nuclear stellar discs (NSDs), we look for their presence in a set of N-body simulations studying the dissipationless merging of multiple star clusters in galactic nuclei. A few tens of star clusters with sizes and masses comparable to those of globular clusters observed in the Milky Way are accreted on to a pre-existing nuclear stellar component: either a massive super star cluster or a rapidly rotating, compact disc with a scalelength of a few parsecs, mimicking the variety of observed nuclear structures. Images and kinematic maps of the simulation time-steps are then built and analysed as if they were real and at the distance of the Virgo cluster. We use the Scorza–Bender method to search for the presence of disc structures via photometric decomposition. In one case, the merger remnant has all the observed photometric and kinematic properties of NSDs observed in real galaxies. This shows that current observations are consistent with most of the NSD mass being assembled from the migration and accretion of star clusters into the galactic centre. In the other simulation instead, we detect an elongated structure from the unsharp masked image, that does not develop the photometric or kinematic signature of an NSD. Thus, in the context of searches for a disc structure, the Scorza–Bender method is a robust and necessary tool.
23095524
μ Eridani from MOST and from the ground: an orbit, the SPB component's fundamental parameters and the SPB frequencies
MOST time-series photometry of mu Eri, an SB1 eclipsing binary with a rapidly-rotating SPB primary, is reported and analyzed. The analysis yields a number of sinusoidal terms, mainly due to the intrinsic variation of the primary, and the eclipse light-curve. New radial-velocity observations are presented and used to compute parameters of a spectroscopic orbit. Frequency analysis of the radial-velocity residuals from the spectroscopic orbital solution fails to uncover periodic variations with amplitudes greater than 2 km/s. A Rossiter-McLaughlin anomaly is detected from observations covering ingress. 
From archival photometric indices and the revised Hipparcos parallax we derive the primary's effective temperature, surface gravity, bolometric correction, and the luminosity. An analysis of a high signal-to-noise spectrogram yields the effective temperature and surface gravity in good agreement with the photometric values. From the same spectrogram, we determine the abundance of He, C, N, O, Ne, Mg, Al, Si, P, S, Cl, and Fe. 
The eclipse light-curve is solved by means of EBOP. For a range of mass of the primary, a value of mean density, very nearly independent of assumed mass, is computed from the parameters of the system. Contrary to a recent report, this value is approximately equal to the mean density obtained from the star's effective temperature and luminosity. 
Despite limited frequency resolution of the MOST data, we were able to recover the closely-spaced SPB frequency quadruplet discovered from the ground in 2002-2004. The other two SPB terms seen from the ground were also recovered. Moreover, our analysis of the MOST data adds 15 low-amplitude SPB terms with frequencies ranging from 0.109 c/d to 2.786 c/d.
121528801
Measurement of the lifetime of heavy Λ hypernuclei with the recoil shadow method and internal targets in the storage ring COSY-Jülich
Abstract For the measurement of the lifetime of the Λ hyperon in very heavy hypernuclei we have used proton projectiles for the production of strangeness and the recoil shadow method in the circulating beam of COSY-Julich. This permitted us to use a very thin ribbon target without loss in luminosity. The target fabrication and frameless mounting is described in detail. A special mode of operating COSY was developed in order to bump the beam onto the target and to apply a supercycle. A description is given of the apparatus, tests, the calibration and the data analysis. As an example the p+Bi results are presented and discussed.
121039239
Identification of K+-mesons from subthreshold pA collisions with ANKE at COSY-Jülich
Abstract The spectrometer ANKE has been put into operation at the accelerator COSY of the Forschungszentrum Julich in spring 1998. An initial scientific goal is to study K + -production in pA collisions at subthreshold energies far below the free NN-threshold at T p =1.58 GeV. This requires the identification of K + -mesons in a background of pions and protons, about 10 6 times more intense. In this paper the sophisticated detection system and the software procedures for kaon identification are described. With the help of TOF, energy-loss and range measurements as well as the track information from wire chambers, it is possible to measure d 2 σ/ d Ω d p for deep subthreshold K + production at beam energies down to T p =1.0 GeV.
20399784
Observation of an "ABC" Effect in proton-proton collisions.
The cross section for inclusive multipion production in the pp-->ppX reaction was measured at COSY-ANKE at four beam energies, 0.8, 1.1, 1.4, and 2.0 GeV, for low excitation energy in the final pp system, such that the diproton quasiparticle is in the 1S0 state. At the three higher energies, the missing-mass M_{X} spectra show a strong enhancement at low M_{X}, corresponding to an Abashian-Booth-Crowe effect that moves steadily to larger values as the energy is increased. Despite the missing-mass structure looking very different at 0.8 GeV, the variation with M_{X} and beam energy are consistent with two-pion production being mediated through the excitation of two Delta(1232) isobars, coupled to S and D states of the initial pp system. There is no sign of any resonancelike structure in the energy dependence of the type recently observed for the pn-->dpi;{0}pi;{0} total cross section.
120134132
Measurements of the Lambda hyperon lifetime in heavy hypernuclei at COSY-Juelich