# The SPHERE infrared survey for exoplanets (SHINE). III. The demographics of young giant exoplanets below 300 au with SPHERE

**Authors:** A. Vigan, C. Fontanive, M. Meyer, B. Biller, M. Bonavita, M. Feldt, S. Desidera, G. -D. Marleau, A. Emsenhuber, R. Galicher, K. Rice, D. Forgan, C. Mordasini, R. Gratton, H. Le Coroller, A. -L. Maire, F. Cantalloube, G. Chauvin, A. Cheetham, J. Hagelberg  
**arXiv:** [2007.06573](https://arxiv.org/abs/2007.06573)  
**Date:** 2020-07-13  
**Summary page:** https://www.summarizepaper.com/en/paper/2007.06573v1/

## Key points

- The SPHERE infrared survey for exoplanets (SHINE) project is a 500-star survey conducted with the Spectro-Polarimetric High-contrast Exoplanet Research (SPHERE) instrument on the Very Large Telescope (VLT).
- The primary aim of this survey is to directly detect new substellar companions and gain insights into their formation and early evolution.
- An initial statistical analysis was performed on a subsample of 150 stars that are representative of the full SHINE sample.
- The goal was to constrain the frequency of substellar companions with masses between 1 and 75 Jupiter masses (MJup) and semimajor axes between 5 and 300 astronomical units (au).
- Detection limits were adopted as a function of angular separation from the survey data for all stars, which were then converted into mass and projected orbital separation using BEX-COND-hot evolutionary tracks along with known distance to each system.
- Based on the results obtained for each star and on the 13 detections in the sample, they used a Markov Chain Monte Carlo (MCMC) tool to compare their observations to two different types of models.
- Using the parametric model, they showed that systems with at least one substellar companion have frequencies of $23.0_{-9.7}^{+13.5}\%$, $5.8_{-2.8}^{+4.7}\%$, and $12.6_{-7.1}^{+12.9}\%$ for BA, FGK, and M stars respectively.
- They demonstrated that planet-like formation pathways likely dominate in companions around BA stars within the mass range from 1-75 MJup while brown dwarf binaries dominate detections around M dwarfs.
- In contrast, a combination of binary star-like and planet-like formation is required to best fit observations for FGK stars.

## Summary

The SPHERE infrared survey for exoplanets (SHINE) project is a comprehensive 500-star survey conducted with the Spectro-Polarimetric High-contrast Exoplanet Research (SPHERE) instrument on the Very Large Telescope (VLT). The primary aim of this survey is to directly detect new substellar companions and gain insights into their formation and early evolution. In this study, an initial statistical analysis was performed on a subsample of 150 stars that are representative of the full SHINE sample. The goal was to constrain the frequency of substellar companions with masses between 1 and 75 Jupiter masses (MJup) and semimajor axes between 5 and 300 astronomical units (au). The team adopted detection limits as a function of angular separation from the survey data for all stars, which were then converted into mass and projected orbital separation using BEX-COND-hot evolutionary tracks along with known distance to each system. Based on the results obtained for each star and on the 13 detections in the sample, they used a Markov Chain Monte Carlo (MCMC) tool to compare their observations to two different types of models. The first model was a parametric model based on observational constraints, while the second type combined advanced core accretion and gravitational instability planet population synthesis numerical models. Using the parametric model, they showed that systems with at least one substellar companion have frequencies of $23.0_{-9.7}^{+13.5}\%$, $5.8_{-2.8}^{+4.7}\%$, and $12.6_{-7.1}^{+12.9}\%$ for BA, FGK, and M stars respectively. Additionally, they demonstrated that planet-like formation pathways likely dominate in companions around BA stars within the mass range from 1-75 MJup while brown dwarf binaries dominate detections around M dwarfs. In contrast, a combination of binary star-like and planet-like formation is required to best fit observations for FGK stars.