The discovery of the new polar ring galaxy

gri composite image of J0953 taken from hscMap. Credit: Nishimura et al., 2022.

Japanese astronomers report the discovery of a new polar ring galaxy using data obtained with the Subaru telescope as part of the Subaru Hyper Suprime-Cam Strategic Program (HSC-SSP). The discovery was detailed in a paper published August 26 on the arXiv server before printing.

The so-called polar ring galaxies (PRGs) are systems consisting of an S0-like galaxy and a polar ring, remaining separate for billions of years. In general, these outer polar rings, made up of gas and stars, line up roughly in a perpendicular direction with respect to the main axis of the central host galaxy.

However, although more than 400 PRG candidates have been discovered so far, only dozens of them have been confirmed as true polar ring galaxies by follow-up. Spectral notes.

Therefore, in order to expand the current short list of confirmed PRGs, a team of astronomers led by Minoru Nishimura of the Open University of Japan conducted a detailed study of a sample of known PRGs using data from HSC-SSP. As a result, they found a new PRG filter – it was identified as SDSS J095351.58 + 012036.1.

“During this research, we discovered a new PRG filter SDSS J095351.58 + 012036.1 (hereafter J0953). This galaxy is located at the edge of the Cosmic Evolution Survey (COSMOS; Scoville et al. (2007)),” the researchers wrote in the paper.

J0953 was initially identified as a galaxy in 2000 by the Sloan Digital Sky Survey (SDSS). It has an optical redshift of about 0.2, however, since no spectroscopic observations of J0953 have been made so far, no spectral redshift is currently available for this source.

According to the study, J0953 has a file stellar cluster From about 38.5 billion solar masses The rate of star formation is about 2.66 solar masses per year. The stellar masses of the host galaxy and the polar structure are found to be 26.18 and 4.23 billion solar masses, respectively. The radius of the host galaxy was measured as 0.89 arcseconds, while the radius of the polar structure was found to be 2.12 arcseconds.

Astronomers have noticed that J0953’s polar ring structure appears roughly perpendicular to the disk of its host galaxy without any turbulent features. They report that the polar structure is blue and possibly smaller than the host galaxy.

Furthermore, it was found that the host galaxy’s Sérsic index is 2.94, which indicates that the host galaxy has an elliptical galaxy-like structure rather than an exponential disk. It’s also possible that the host galaxy is a disk galactic, the researchers added.

Summing up the results, the study authors emphasized that further spectroscopic observations of J0953 must be performed in order to finally confirm the nature of PRG. In particular, further investigation of the kinetic properties of both the host galaxy and the polar structure is required.


Hubble depicts a complex galactic trio


more information:
Minoru Nishimura, Kazuya Matsubayashi, Takashi Murayama, Yoshiaki Taniguchi, a new polar galaxy discovered in the COSMOS field. arXiv: 2208.12388v1 [astro-ph.GA]And the arxiv.org/abs/2208.12388

© 2022 Science X Network

the quote: New Polar Galaxy Discovered (2022, Sep 5) Retrieved Sep 5, 2022 from

This document is subject to copyright. Notwithstanding any fair dealing for the purpose of private study or research, no part may be reproduced without written permission. The content is provided for informational purposes only.