Orbital characterization of GJ1108A system, and comparison of dynamical mass with model-derived mass for resolved binaries

We report an orbital characterization of GJ1108Aab that is a low-mass binary system in pre-main-sequence phase. Via the combination of astrometry using adaptive optics and radial velocity measurements, an eccentric orbital solution of $e$=0.63 is obtained, which might be induced by the Kozai-Lidov mechanism with a widely separated GJ1108B system. Combined with several observed properties, we confirm the system is indeed young. Columba is the most probable moving group, to which the GJ1108A system belongs, although its membership to the group has not been established. If the age of Columba is assumed for GJ1108A, the dynamical masses of both GJ1108Aa and GJ1108Ab ($M_{\rm dynamical,GJ1108Aa}=0.72\pm0.04 M_{\odot}$ and $M_{\rm dynamical,GJ1108Ab}=0.30\pm0.03 M_{\odot}$) are more massive than what an evolutionary model predicts based on the age and luminosities. We consider the discrepancy in mass comparison can attribute to an age uncertainty; the system is likely older than stars in Columba, and effects that are not implemented in classical models such as accretion history and magnetic activity are not preferred to explain the mass discrepancy. We also discuss the performance of the evolutionary model by compiling similar low-mass objects in evolutionary state based on the literature. Consequently, it is suggested that the current model on average reproduces the mass of resolved low-mass binaries without any significant offsets.Comment: Accepted in Ap

SEEDS direct imaging of the RV-detected companion to V450 Andromedae, and characterization of the system

We report the direct imaging detection of a low-mass companion to a young, moderately active star V450 And, that was previously identified with the radial velocity method. The companion was found in high-contrast images obtained with the Subaru Telescope equipped with the HiCIAO camera and AO188 adaptive optics system. From the public ELODIE and SOPHIE archives we extracted available high-resolution spectra and radial velocity (RV) measurements, along with RVs from the Lick planet search program. We combined our multi-epoch astrometry with these archival, partially unpublished RVs, and found that the companion is a low-mass star, not a brown dwarf, as previously suggested. We found the best-fitting dynamical masses to be $m_1=1.141_{-0.091}^{+0.037}$ and $m_2=0.279^{+0.023}_{-0.020}$ M$_\odot$. We also performed spectral analysis of the SOPHIE spectra with the iSpec code. The Hipparcos time-series photometry shows a periodicity of $P=5.743$ d, which is also seen in SOPHIE spectra as an RV modulation of the star A. We interpret it as being caused by spots on the stellar surface, and the star to be rotating with the given period. From the rotation and level of activity, we found that the system is $380^{+220}_{-100}$ Myr old, consistent with an isochrone analysis ($220^{+2120}_{-90}$ Myr). This work may serve as a test case for future studies of low-mass stars, brown dwarfs and exoplanets by combination of RV and direct imaging data.Comment: 15 pages, 9 figures, 7 tables, to appear in Ap

Characterization of the gaseous companion {\kappa} Andromedae b: New Keck and LBTI high-contrast observations

We previously reported the direct detection of a low mass companion at a projected separation of 55+-2 AU around the B9 type star {\kappa} Andromedae. The properties of the system (mass ratio, separation) make it a benchmark for the understanding of the formation and evolution of gas giant planets and brown dwarfs on wide-orbits. We present new angular differential imaging (ADI) images of the Kappa Andromedae system at 2.146 (Ks), 3.776 (L'), 4.052 (NB 4.05) and 4.78 {\mu}m (M') obtained with Keck/NIRC2 and LBTI/LMIRCam, as well as more accurate near-infrared photometry of the star with the MIMIR instrument. We derive a more accurate J = 15.86 +- 0.21, H = 14.95 +- 0.13, Ks = 14.32 +- 0.09 mag for {\kappa} And b. We redetect the companion in all our high contrast observations. We confirm previous contrasts obtained at Ks and L' band. We derive NB 4.05 = 13.0 +- 0.2 and M' = 13.3 +- 0.3 mag and estimate Log10(L/Lsun) = -3.76 +- 0.06. We build the 1-5 microns spectral energy distribution of the companion and compare it to seven PHOENIX-based atmospheric models in order to derive Teff = 1900+100-200 K. Models do not set constrains on the surface gravity. ``Hot-start" evolutionary models predict masses of 14+25-2 MJup based on the luminosity and temperature estimates, and considering a conservative age range for the system (30+120-10 Myr). ``warm-start" evolutionary tracks constrain the mass to M >= 11 MJup. Therefore, the mass of {\kappa} Andromedae b mostly falls in the brown-dwarf regime, due to remaining uncertainties in age and mass-luminosity models. According to the formation models, disk instability in a primordial disk could account for the position and a wide range of plausible masses of {\kappa} And b.Comment: 20 pages, 16 figures, accepted for publication in Astronomy and Astrophysics on August 6, 201

Supersymmetry breaking induced by radiative corrections

We show that simultaneous gauge and supersymmetry breaking can be induced by radiative corrections, a la Coleman-Weinberg. When a certain correlation among the superpotential parameters is present, a local supersymmetry-breaking minimum is found in the effective potential of a gauge non-singlet field, in a region where the tree-level potential is almost flat. Supersymmetry breaking is then transmitted to the MSSM through gauge and chiral messenger loops, thus avoiding the suppression of gaugino masses characteristic of direct gauge mediation models. The use of a single field ensures that no dangerous tachyonic scalar masses are generated at the one-loop level. We illustrate this mechanism with an explicit example based on an SU(5) model with a single adjoint. An interesting feature of the scenario is that the GUT scale is increased with respect to standard unification, thus allowing for a larger colour Higgs triplet mass, as preferred by the experimental lower bound on the proton lifetime.Comment: 22 pages, 3 figures. Two references added, small redactional changes, some discussion improved. Results unchange

Pipe3d, a pipeline to analyze integral field spectroscopy data: II Analysis sequence and califa dataproducts

Presentamos una version mejorada de FIT3D, una herramienta de ajuste para el analisis de las poblaciones estelares y el gas ionizado en espectros de galaxias de resolucion intermedia. La misma se desarrollo para el análisis de datos de espectroscopía de campo integral y es la base de Pipe3D, un dataducto usado en el analisis de datos de los muestreos CALIFA, MaNGA y SAMI. Describimos la filosof´ıa y los pasos seguidos en el ajuste, presentando un conjunto amplio de simulaciones con el fin de estimar la precisión de los parametros derivados, mostrando el resultado de dichas simulaciones. Finalmente, comparamos el resultado del analisis con FIT3D y el obtenido mediante otros paquetes de uso frecuente, encontrando que los parametros derivados son totalmente compatibles.We present Pipe3D, an analysis pipeline based on the FIT3D fitting tool, developed to explore the properties of the stellar populations and ionized gas of integral field spectroscopy (IFS) data. Pipe3D was created to provide coherent, simple to distribute, and comparable dataproducts, independently of the origin of the data, focused on the data of the most recent IFU surveys (e.g., CALIFA, MaNGA, and SAMI), and the last generation IFS instruments (e.g., MUSE). In this article we describe the di fferent steps involved in the analysis of the data, illustrating them by showing the dataproducts derived for NGC 2916, observed by CALIFA and P-MaNGA. As a practical example of the pipeline we present the complete set of dataproducts derived for the 200 datacubes that comprises the V500 setup of the CALIFA Data Release 2 (DR2), making them freely available through the network. Finally, we explore the hypothesis that the properties of the stellar populations and ionized gas of galaxies at the e ffective radius are representative of the overall average ones, finding that this is indeed the case.Fil: Sánchez, S. F.. Universidad Nacional Autonoma de Mexico. Instituto de Astronomia; MéxicoFil: Pérez, E.. Instituto de Astrofísica de Andalucía; España. Consejo Superior de Investigaciones Científicas; EspañaFil: Sanchez Blazquez, P.. Departamento de Fisica Teorica ; Facultad de Ciencias ; Universidad Autonoma de Madrid;Fil: García Benito, Rubén. Instituto de Astrofísica de Andalucía; España. Consejo Superior de Investigaciones Científicas; EspañaFil: Ibarra Mede, H. J.. Space Telescope Science Institute; Estados UnidosFil: González, J. J.. Universidad Nacional Autonoma de Mexico. Instituto de Astronomia; MéxicoFil: Rosales Ortega, F. F.. Instituto Nacional de Astrofísica, Optica y Electrónica ; MéxicoFil: Sánchez Menguiano, L.. Instituto de Astrofísica de Andalucía; España. Consejo Superior de Investigaciones Científicas; EspañaFil: Ascasibar, Y.. Universidad Autónoma de Barcelona. Facultad de Física. Departamento Astronomía y Meteorología; EspañaFil: Bitsakis, T.. Universidad Nacional Autonoma de Mexico. Instituto de Astronomia; MéxicoFil: Law, D.. Space Telescope Science Institute; Estados UnidosFil: Cano Díaz, M.. Universidad Nacional Autonoma de Mexico. Instituto de Astronomia; MéxicoFil: López Cobá, C.. Universidad Nacional Autonoma de Mexico. Instituto de Astronomia; MéxicoFil: Marino, R. A.. Universidad Complutense de Madrid; EspañaFil: Gil de Paz, A.. Australian Astronomical Observatory; AustraliaFil: López Sánchez, A.. Instituto de Astrofísica de Canarias (iac); EspañaFil: Barrera Ballesteros, Jorge K.. Instituto de Astrofísica de Canarias; EspañaFil: Galbany, Lluís. Millennium Institute Of Astrophysics; Chile. Universidad de Chile; ChileFil: Mast, Damian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; ArgentinaFil: Abril Malgarejo, V.. Universidad Nacional Autonoma de Mexico. Instituto de Astronomia; MéxicoFil: Roman Lopes, A.. Universidad de La Serena; Chil