Observation of S4716 -- a Star with a 4 yr Orbit around Sgr A*

TL;DR

This paper reports the discovery of a new star, S4716, orbiting Sgr A* with a 4-year period, using advanced observational techniques, revealing insights into the dynamics of stars near the Galactic center.

Contribution

The paper introduces the discovery of S4716, a star with a 4-year orbit around Sgr A*, and discusses its implications for understanding stellar dynamics near the supermassive black hole.

Findings

S4716 orbits Sgr A* in about 4 years.

S4716 has a periapse distance of about 100 au.

S4716 shares similar orbital properties with S4711.

Abstract

The ongoing monitoring of the Galactic center and Sgr A*, the central supermassive black hole, produces surprising and unexpected findings. This goes hand in hand with the technical evolution of ground- and space-based telescopes and instruments, but also with the progression of image filter techniques such as the Lucy Richardson algorithm. As we continue to trace the members of the S cluster close to Sgr A* on their expected trajectory around the supermassive black hole, we present the finding of a new stellar source, which we call S4716. The newly found star orbits SgrA* in about 4.0 yr and can be detected with NIRC2 (Keck), OSIRIS (Keck), SINFONI (VLT), NACO (VLT), and GRAVITY (VLTI). With a periapse distance of about 100 au, S4716 shows an equivalent distance toward Sgr A* as S4711. These fast-moving stars undergo a similar dynamical evolution, since S4711-S4716 share comparable orbital properties. We will furthermore draw a connection between the recent finding of a new faint star called S300 and the data presented here. Additionally, we observed a blend-star event with S4716 and another newly identified S star S148 in 2017.