Observation of the apoapsis of S62 in 2019 with NIRC2 and SINFONI

TL;DR

This study confirms the detection of the faint star S62 at its apoapsis in 2019 using advanced imaging techniques, providing precise orbital and brightness measurements around the Galactic center's supermassive black hole.

Contribution

It demonstrates the successful detection and characterization of S62 at apoapsis using Lucy-Richardson deconvolution and independent datasets, clarifying previous uncertainties.

Findings

S62 was detected at the expected position in 2019.

The star's magnitude was confirmed as 16.1 ± 0.2 mag.

The study discusses the disputed identification of a 19 mag star.

Abstract

Given the increased attention towards the detection of faint stars in the Galactic center, we would like to address the detectability of S62 in its apoapsis with SINFONI (VLT) and NIRC2 (KECK) in this work. Because of the nearby stars and the chance of confusion, we are using Lucy-Richardson deconvolved images to detect S62 on its Keplerian orbit around Sgr~A* with a period of less than 10 years. We use the same dataset as for S62 to trace additionally the S-cluster star S29 at the expected position based on the orbital elements presented in this work. To verify the results of the filtering technique, we are analysing K-band continuum data of the same epoch independently observed with NIRC2/KECK. Based on the well-derived orbit of S62, we find the star in projection at the expected position in 2019.4 and 2019.5. By analyzing the SINFONI data of 2019.5, we confirm the $16.1\,\pm\,0.2$ mag for S62 that was formerly derived with NACO (VLT). We base our NACO imaging analysis on the robust data set that was previously used to investigate the Schwarzschild precision of S2. We also present a critical discussion of the elsewhere proposed linear trajectory of S62 and its disputed identification with a 19 mag star found with GRAVITY mounted at the VLT Interferometer.