A first attempt to differentiate between modified gravity and modified inertia with galaxy rotation curves

The phenomenology of modified Newtonian dynamics (MOND) on galaxy scales may point to more fundamental theories of either modified gravity (MG) or modified inertia (MI). In this paper, we test the applicability of the global deep-MOND parameter Q which is predicted to vary at the 10% level between MG and MI theories. Using mock-observed analytical models of disk galaxies, we investigate several observational uncertainties, establish a set of quality requirements for actual galaxies, and derive systematic corrections in the determination of Q. Implementing our quality requirements to the SPARC database yields 15 galaxies, which are close enough to the deep-MOND regime as well as having rotation curves that are sufficiently extended and sampled. For these galaxies, the average and median values of Q seem to favor MG theories, albeit both MG and MI predictions are in agreement with the data within 1.5σ. Improved precision in the determination of Q can be obtained by measuring extended and finely-sampled rotation curves for a significant sample of extremely low-surface-brightness galaxies.

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The prediction of rotation curves in gas-dominated dwarf galaxies with modified dynamics

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz353 ◽

2019 ◽

Vol 485 (1) ◽

pp. 513-521 ◽

Cited By ~ 5

Author(s):

R H Sanders

Keyword(s):

Surface Density ◽

Surface Brightness ◽

Dark Halo ◽

Baryonic Matter ◽

Rotation Curves ◽

Stellar Disc ◽

Modified Newtonian Dynamics ◽

Newtonian Dynamics ◽

Low Surface Brightness ◽

Low Surface Brightness Galaxies

ABSTRACT I consider the observed rotation curves of 12 gas-dominated low-surface-brightness galaxies – objects in which the mass of gas ranges between 2.2 and 27 times the mass of the stellar disc (mean = 9.4). This means that, in the usual decomposition of rotation curves into those resulting from various mass components, the mass-to-light ratio of the luminous stellar disc effectively vanishes as an additional adjustable parameter. It is seen that the observed rotation curves reflect the observed structure in gas surface density distribution often in detail. This fact is difficult to comprehend in the context of the dark matter paradigm where the dark halo completely dominates the gravitational potential in the low surface density systems; however it is an expected result in the context of modified Newtonian dynamics (MOND) in which the baryonic matter is the only component. With MOND the calculated rotation curves are effectively parameter-free predictions.

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The Central Dynamics of Blue Low Surface Brightness Galaxies

Symposium - International Astronomical Union ◽

10.1017/s0074180900183573 ◽

2004 ◽

Vol 220 ◽

pp. 335-336

Author(s):

Erik Zackrisson ◽

Nils Bergvall

Keyword(s):

Dark Matter ◽

Density Profile ◽

Surface Brightness ◽

Cold Dark Matter ◽

Central Density ◽

Disk Galaxies ◽

Rotation Curves ◽

Central Surface ◽

Low Surface Brightness ◽

Low Surface Brightness Galaxies

We use optical, long-slit rotation curves to derive the slope of the central density profile in three blue disk galaxies with very faint central surface brightness values. We find the result to be in conflict with current cold dark matter predictions and to lend further support for pseudo-isothermal spheres as superior models for the dark halos of galaxies.

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Kinematics of Giant Low Surface Brightness Galaxies

International Astronomical Union Colloquium ◽

10.1017/s025292110005435x ◽

1999 ◽

Vol 171 ◽

pp. 214-220 ◽

Cited By ~ 1

Author(s):

T.E. Pickering

Keyword(s):

Dark Matter ◽

Surface Brightness ◽

Dwarf Galaxies ◽

High Sensitivity ◽

Disk Galaxies ◽

Optical Surface ◽

Rotation Curves ◽

Low Surface Brightness ◽

Low Surface Brightness Galaxies ◽

Dynamical Masses

AbstractHigh sensitivity H I observations now exist for six giant low surface brightness (LSB) disk galaxies including the two prototypes, Malin 1 (Bothun et al. 1987; Impey & Bothun 1989) and F568-6 (also known as Malin 2; Bothun et al. 1990). Their H I surface brightnesses are generally low, but proportionally not as low as their optical surface brightnesses. Their total H I masses and radial extents are quite large, however, with MHI ∼ 1010M⊙h−275 and with detectable H I out to 100 kpc h−175 or more in a couple of cases. The rotation curves of these systems rise slowly and are consistent with negligible disk contribution, similar to many previously observed dwarf galaxies. However, the peak rotation velocities of these galaxies are high (>200 km s−1) and infer high dynamical masses. These galaxies provide the some of the first examples of galaxies that are both massive and dark matter dominated.

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TESTING MODIFIED NEWTONIAN DYNAMICS WITH ROTATION CURVES OF DWARF AND LOW SURFACE BRIGHTNESS GALAXIES

The Astrophysical Journal ◽

10.1088/0004-637x/718/1/380 ◽

2010 ◽

Vol 718 (1) ◽

pp. 380-391 ◽

Cited By ~ 63

Author(s):

R. A. Swaters ◽

R. H. Sanders ◽

S. S. McGaugh

Keyword(s):

Surface Brightness ◽

Rotation Curves ◽

Modified Newtonian Dynamics ◽

Newtonian Dynamics ◽

Low Surface Brightness ◽

Low Surface Brightness Galaxies

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The Size-Luminosity Relation of Disk Galaxies in EDisCS Clusters

Proceedings of the International Astronomical Union ◽

10.1017/s1743921306006077 ◽

2006 ◽

Vol 2 (S235) ◽

pp. 201-201

Author(s):

Stephanie M. Gogarten ◽

Julianne J. Dalcanton ◽

Luc Simard ◽

Gregory Rudnick ◽

Vandana Desai ◽

...

Keyword(s):

Surface Brightness ◽

High Redshift ◽

Disk Galaxies ◽

Selection Effects ◽

Distant Cluster ◽

Cluster Survey ◽

Low Surface Brightness ◽

Advanced Camera For Surveys ◽

Low Surface Brightness Galaxies

AbstractWe present the size-luminosity relation (SLR) for disk galaxies observed in eight clusters from the ESO Distant Cluster Survey (EDisCS). These clusters, at redshifts 0.4 < z < 0.8, were observed with the Hubble Space Telescope's Advanced Camera for Surveys. While we observe a change in the SLR with redshift, namely that there is an absence of low surface brightness galaxies at high redshift, we demonstrate that this could be a product of selection effects and thus is not a confirmation of evolution. We also compare the SLR for cluster and field galaxies in each redshift bin and see no significant effects of environment on the SLR.

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