LAUSR.org creates dashboard-style pages of related content for over 1.5 million academic articles. Sign Up to like articles & get recommendations!

Towards a higher mass forNGC 1052-DF2: an analysis based on full distribution functions

Photo by dawson2406 from unsplash

It is demonstrated that the kinematics of the 10 star clusters in NGC2052-DF2 is compatible with a high dynamical mass close to those implied by the standard stellar-to-halo-mass ratio (SHMR).… Click to show full abstract

It is demonstrated that the kinematics of the 10 star clusters in NGC2052-DF2 is compatible with a high dynamical mass close to those implied by the standard stellar-to-halo-mass ratio (SHMR). The analysis relies on a convenient form for the distribution function (DF) of projected phase space data, capturing non-gaussian features in the spread of true velocities of the mass tracers. A key ingredient is tidal stripping by the gravity of the apparently nearby larger galaxy, NGC 1052. Tidal stripping decreases the range of velocities of mass tracers, while only mildly lowering the total mass inside the trimming radius $r_{tr}$. The analysis is performed assuming halo profiles consistent with simulations of the $\Lambda$CDM model. For the fiducial value $r_{tr}=10$ kpc, we find that the virial mass of the pre-trimmed halo is $M<1.6\times 10^{10}M_\odot$ at $2\sigma $ ($95\%$) and $M<8.6\times 10^{9}M_\odot$ at $1.64\sigma$ ($90\%$). For the mass within 10 kpc we obtain, $M_\mathrm{10kpc}<3.9\times 10^{9}M_\odot$ and $<2.9\times 10^{9}M_\odot$ at $2\sigma$ and $1.64\sigma$, respectively. The $2\sigma$ upper limit on the virial mass is roughly a factor of 3-5 below the mean SHMR relation.Taking $r_{tr}=20$ kpc, lowers the $2\sigma$ virial mass limits by a factor of $\sim 4 $, bringing our results closer to those of Wasserman et al. (2018) without their SHMR prior.

Keywords: analysis; mass; df2; times odot; virial mass; distribution

Journal Title: Monthly Notices of the Royal Astronomical Society
Year Published: 2019

Link to full text (if available)


Share on Social Media:                               Sign Up to like & get
recommendations!

Related content

More Information              News              Social Media              Video              Recommended



                Click one of the above tabs to view related content.