Super-massive black hole wake or bulgeless edge-on galaxy?
arXiv:2304.12344 · doi:10.1051/0004-6361/202346430
Abstract
van Dokkum et al. (2023) reported the serendipitous discovery of a thin linear object interpreted as the trail of star-forming regions left behind by a runaway supermassive black hole (SMBH) kicked out from the center of a galaxy. Despite the undeniable interest in the idea, the actual physical interpretation is not devoid of difficulty. The wake of a SMBH produces only small perturbations on the external medium, which has to be in exceptional physical conditions to collapse gravitationally and form a long (40 kpc) massive (3e9 Msun) stellar trace in only 39 Myr. Here we offer a more conventional explanation: the stellar trail is a bulgeless galaxy viewed edge-on. This interpretation is supported by the fact that its position--velocity curve resembles a rotation curve which, together with its stellar mass, puts the object right on top of the Tully-Fisher relation characteristic of disk galaxies. Moreover, the rotation curve (Vmax sim 110 km/s), stellar mass, extension, width (z0 sim 1.2 kpc), and surface brightness profile of the object are very much like those of IC5249, a well-known local bulgeless edge-on galaxy. These observational facts are difficult to interpret within the SMBH wake scenario. We discuss in detail the pros and cons of the two options.
Accepted for publication in A&A Letters
References in corpus (10)
- The propagation of uncertainties in stellar population synthesis modeling I: The relevance of uncertain aspects of stellar evolution and the IMF to the derived physical properties of galaxies
- SPARC: Mass Models for 175 Disk Galaxies with Spitzer Photometry and Accurate Rotation Curves
- Strong Nebular Line Ratios in the Spectra of z~2-3 Star-forming Galaxies: First Results from KBSS-MOSFIRE
- Strongly baryon-dominated disk galaxies at the peak of galaxy formation ten billion years ago
- A physically motivated definition for the size of galaxies in an era of ultra-deep imaging
- The Catalog of Edge-on Disk Galaxies from SDSS. Part I: the catalog and the Structural Parameters of Stellar Disks
- The edges of galaxies: Tracing the limits of star formation
- A candidate runaway supermassive black hole identified by shocks and star formation in its wake
- Very Thin Disc Galaxies in The SDSS Catalog of Edge-on Galaxies
- Stellar feedback in M83 as observed with MUSE -- I. Overview, an unprecedented view of the stellar and gas kinematics and evidence of outflowing gas