English

A Dearth of Atomic Hydrogen in NGC1052-DF2

Astrophysics of Galaxies 2018-11-01 v2

Abstract

The recently claimed discovery of an ultra-diffuse galaxy lacking dark matter has important implications for alternate theories to dark matter as well as models of galaxy formation within the Λ\LambdaCDM context. In this letter, we present a deep Giant Metrewave Radio Telescope (GMRT) search for atomic hydrogen in this ultra-diffuse galaxy, NGC1052-DF2. We report a non-detection of the HI21cm transition from the galaxy and place a stringent upper-limit on the HI mass of the galaxy - MHI<3.15×106 (ΔV/20 km/s)1/2 M (3σ)M_{HI} < 3.15 \times 10^6 \ ({\Delta V}/20 \ \textrm{km/s})^{1/2} \ M_\odot \ (3\sigma). This makes NGC1052-DF2 an extremely gas poor galaxy with an atomic gas to stellar mass fraction of MHI/M < 0.016 (ΔV/20 km/s)1/2 (3σ)M_{HI}/M_* \ < \ 0.016 \ ({\Delta V}/20 \ \textrm{km/s})^{1/2} \ (3\sigma). Such low gas fractions are typical of dwarf ellipticals in dense environments and would be consistent with NGC1052-DF2 having undergone a tidal stripping event which can also explain its apparent lack of dark matter.

Keywords

Cite

@article{arxiv.1810.04938,
  title  = {A Dearth of Atomic Hydrogen in NGC1052-DF2},
  author = {Aditya Chowdhury},
  journal= {arXiv preprint arXiv:1810.04938},
  year   = {2018}
}

Comments

4 pages, 2 figures; updated to match version published in MNRAS letters