DARK AND LUMINOUS MATTER IN THINGS DWARF GALAXIES

By Se-Heon Oh, W. D. de Blok, E. Brinks, F. Walter, Robert C. Kennicutt Jr.. 2010

367 citations recorded by the source corpus.

We present mass models for the dark matter component of seven dwarf galaxies taken from “The H i Nearby Galaxy Survey” (THINGS) and compare these with those taken from numerical Λ cold dark matter (ΛCDM) simulations. The THINGS high-resolution data significantly reduce observational uncertainties and thus allow us to derive accurate dark matter distributions in these systems. We here use the bulk velocity fields when deriving the rotation curves of the galaxies. Compared to other types of velocity fields, the bulk velocity field minimizes the effect of small-scale random motions more effectively and traces the underlying kinematics of a galaxy more properly. The “Spitzer Infrared Nearby Galaxies Survey” 3.6 μm and ancillary optical data are used for separating the baryons from their total matter content in the galaxies. The sample dwarf galaxies are found to be dark matter dominated over most radii. The relation between total baryonic (stars + gas) mass and maximum rotation velocity of the galaxies is roughly consistent with the baryonic Tully–Fisher relation calibrated from a larger sample of gas-dominated low-mass galaxies. We find discrepancies between the derived dark matter distributions of the galaxies and those of ΛCDM simulations, even after corrections for non-circular motions have been applied. The observed solid body-like rotation curves of the galaxies rise too slowly to reflect the cusp-like dark matter distribution in cold dark matter halos. Instead, they are better described by core-like models such as pseudo-isothermal halo models dominated by a central constant-density core. The mean value of the logarithmic inner slopes of the mass density profiles is α = −0.29 ± 0.07. They are significantly different from the steep slope of ∼ − 1.0 inferred from previous dark-matter-only simulations, and are more consistent with shallower slopes found in recent ΛCDM simulations of dwarf galaxies in which the effects of baryonic feedback processes are included.

Subfields: Astronomy and Astrophysics, Instrumentation, Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/d931b1d2c120bc77c9ae065cc32a897b595e302e

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

In Instrumentation

In Nuclear and High Energy Physics

Citations in the corpus

Galactic Searches for Dark Matter (2012, background): “This model provides an appealing explanation for low surface brightness galaxies, for which there is now good indication that the central densities are flatter than the Einasto model (Oh et al., 2011).”
The dependence of dark matter profiles on the stellar-to-halo mass ratio: a prediction for cusps versus cores (2013, result): “We note that, in agreement with our findings, the most clear observational measurements of flattened “core” profiles of disc galaxies (de Blok et al. 2008; Kuzio de Naray et al. 2008, 2009; Oh et al. 2011) are found in low surface brightness (LSB) galaxies withVrot < 100 kms−1.”
THE CENTRAL SLOPE OF DARK MATTER CORES IN DWARF GALAXIES: SIMULATIONS VERSUS THINGS (2010, methodology): “As discussed in Oh et al. (2011) (see also de Blok et al. 2008), the hermite h3 velocity field gives a robust estimate for the underlying circular rotation of a galaxy in which non-circular motions are insignificant, like DG1 and DG2.”
Cosmological Simulations with Self-Interacting Dark Matter I: Constant Density Cores and Substructure (2012, background): “…in the range 50 − 130 km/s, constant-density cores with sizes of∼ 0.5 − 8 kpc and central densities of approximately∼ 0.01 − 0.5M⊙/pc 3 have been observed (de Blok et al. 2001; Simon et al. 2005; Sánchez-Salcedo 2005; Kuzio de Naray et al. 2008, 2010; Oh et al. 2011; Salucci et al. 2012).”
The masses and density profiles of halos in a LCDM galaxy formation simulation (2014, background): “…Salucci & Burkert 2000; Swaters et al. 2003; Simon et al. 2005; Gentile et al. 2007; de Blok et al. 2008; Kuzio de Naray, McGaugh & de Blok 2008; Oh et al. 2011), others reporting cusps (even for some of the same galaxies; e.g. Adams et al. 2014), and others arguing that current kinematical…”
HIGH-RESOLUTION MASS MODELS OF DWARF GALAXIES FROM LITTLE THINGS (2015, methodology): “As described in de Blok & Bosma (2002; see also Oh et al. 2011b), we determine a break radius of a DM density profile where the slope changes most rapidly in the inner region of the profile.”
How supernova feedback turns dark matter cusps into cores (2011, background): “As time progresses, both the simulated and model density profiles gradually flatten out, with the value rising from < −1.0 (cusped) to∼−0.4, consistent with observations (Oh et al. 2011a).”
NIHAO – IV: core creation and destruction in dark matter density profiles across cosmic time (2015, background): “Oh et al. 2011b).”
A BARYONIC SOLUTION TO THE MISSING SATELLITES PROBLEM (2012, background): “Governato et al. (2012) and Oh et al. (2011) showed that the density profiles of simulated galaxies within this model are in excellent agreement with the high resolution observations of field galaxies.”
The distribution of dark matter in galaxies (2018, background): “…profile (de Blok et al. 2001; Salucci 2001; Gentile et al. 2004; Simon 2005; Spekkens et al. 2005; Kuzio de Naray et al. 2008; de Blok et al. 2008; Oh et al. 2011; Adams et al. 2014 to name a few, reviews on this issue: Bullock and Boylan-Kolchin 2017; de Blok 2010).9 It is important to remark…”
Dwarf galaxies in CDM and SIDM with baryons: observational probes of the nature of dark matter (2014, background): “…data of Local Group dwarfs (MW+M31 dSphs+dIrrs) (taken from Côté, Carignan & Freeman 2000; McGaugh 2005; Peñarrubia, McConnachie & Navarro 2008; Woo, Courteau & Dekel 2008; Stark, McGaugh & Swaters 2009; Misgeld & Hilker 2011; Oh et al. 2011; Ferrero et al. 2012; Tollerud et al. 2012).”
The Dynamical and Chemical Evolution of Dwarf Spheroidal Galaxies with GEAR (2009, background): “…(Blais-Ouellette et al. 2001; de Blok & Bosma 2002; Swaters et al. 2003; Gentile et al. 2004, 2005; Spekkens et al. 2005; de Blok 2005; de Blok et al. 2008; Spano et al. 2008; Walker & Peñarrubia 2011), including the recent and high resolution observations of the THINGS survey (Oh et al. 2011).”