The McDonald Accelerating Stars Survey (MASS):Discovery of a Long-Period Substellar Companion Orbiting the Old Solar Analog HD 47127

Brown dwarfs with well-determined ages, luminosities, and masses provide rare but valuable tests of low-temperature atmospheric and evolutionary models. We present the discovery and dynamical mass measurement of a substellar companion to HD 47127, an old ($\approx$7-10 Gyr) G5 main sequence star with a mass similar to the Sun. Radial velocities of the host star with the Harlan J. Smith Telescope uncovered a low-amplitude acceleration of 1.93 $\pm$ 0.08 m s$^{-1}$ yr$^{-1}$ based on 20 years of monitoring. We subsequently recovered a faint ($\Delta H$=13.14 $\pm$ 0.15 mag) co-moving companion at 1.95$''$ (52 AU) with follow-up Keck/NIRC2 adaptive optics imaging. The radial acceleration of HD 47127 together with its tangential acceleration from Hipparcos and Gaia EDR3 astrometry provide a direct measurement of the three-dimensional acceleration vector of the host star, enabling a dynamical mass constraint for HD 47127 B (67.5-177 $M_\mathrm{Jup}$ at 95% confidence) despite the small fractional orbital coverage of the observations. The absolute $H$-band magnitude of HD 47127 B is fainter than the benchmark T dwarfs HD 19467 B and Gl 229 B but brighter than Gl 758 B and HD 4113 C, suggesting a late-T spectral type. Altogether the mass limits for HD 47127 B from its dynamical mass and the substellar boundary imply a range of 67-78 $M_\mathrm{Jup}$ assuming it is single, although a preference for high masses of $\approx$100 $M_\mathrm{Jup}$ from dynamical constraints hints at the possibility that HD 47127 B could itself be a binary pair of brown dwarfs or that another massive companion resides closer in. Regardless, HD 47127 B will be an excellent target for more refined orbital and atmospheric characterization in the future.Comment: Accepted to ApJ Letter

Conduct disorder and antisocial personality disorders: challenges for treatment in adolescence and young adulthood

Aggressive behaviour is a typical phenomenon in childhood and adolescence. Aggression is one of the frequent reasons for parents to seek child and adolescent psychiatric and psychotherapeutic treatment. Disorders with increased aggressive behaviour, such as conduct or oppositional defiant disorder, carry an increased risk for long-lasting negative impact on well-being, especially when comorbid with substance abuse or affective symptoms. Barriers for treatment are frequently a lack of insight into consequences and non-compliance with intervention shown by adolescents. In addition, interdisciplinary intervention needs to combine psychiatric and psychotherapeutic interventions as well as complex interventions supported by the youth welfare system, and in particular including families. Further research is needed for the implementation of evidence-based treatments in routine care as well in special populations, such as girls with conduct disorders or youth with substance abuse