The isolated dSph galaxy KKs3 in the local Hubble flow

Караченцев, И. Д.; Kniazev, A. Y.; Шарина, М. Е.

doi:10.1002/asna.201512207

Cited by 15 publications

(10 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This isolated dwarf has 1 GC (M V = −8.33, M * = 3.45 × 10 5 M ) discovered in HST/ACS imaging by Karachentsev et al (2015). The galaxy is located 2 Mpc just outside of the Local Group, with M B = -10.8 (M * ∼ 4.5 × 10 6 M ).…”

Section: A2 Kks3 (Pgc 009140)mentioning

confidence: 87%

Extending the globular cluster system–halo mass relation to the lowest galaxy masses

Forbes

Read

Gieles

et al. 2018

Monthly Notices of the Royal Astronomical Society

140

123

View full text Add to dashboard Cite

High mass galaxies, with halo masses M 200 ≥ 10 10 M , reveal a remarkable near-linear relation between their globular cluster (GC) system mass and their host galaxy halo mass. Extending this relation to the mass range of dwarf galaxies has been problematic due to the difficulty in measuring independent halo masses. Here we derive new halo masses based on stellar and HI gas kinematics for a sample of nearby dwarf galaxies with GC systems. We find that the GC system mass-halo mass relation for galaxies populated by GCs holds from halo masses of M 200 ∼ 10 14 M down to below M 200 ∼ 10 9 M , although there is a substantial increase in scatter towards low masses. In particular, three well-studied ultra diffuse galaxies, with dwarf-like stellar masses, reveal a wide range in their GC-to-halo mass ratios. We compare our GC systemhalo mass relation to the recent model of El Badry et al., finding that their fiducial model does not reproduce our data in the low mass regime. This may suggest that GC formation needs to be more efficient than assumed in their model, or it may be due to the onset of stochastic GC occupation in low mass halos. Finally, we briefly discuss the stellar mass-halo mass relation for our low mass galaxies with GCs, and we suggest some nearby dwarf galaxies for which searches for GCs may be fruitful. Hudson et al. (2014), using weak lensing results from the CFHTLenS survey and the database of GC systems from Harris et al. (2013), were able to extend the relation down to stellar masses of M * ∼10 8 M . They measured a GC system mass to halo mass ratio of 4 (× 10 −5 )

show abstract

Section: A2 Kks3 (Pgc 009140)mentioning

confidence: 87%

Extending the globular cluster system–halo mass relation to the lowest galaxy masses

Forbes

Read

Gieles

et al. 2018

Monthly Notices of the Royal Astronomical Society

140

123

View full text Add to dashboard Cite

show abstract

“…At > 2 Rvir, there are several passive dwarfs with M ∼ 10 6 − 10 8 M in the Local Volume: Tucana, KK258, KKs3, and KKR 25 (Lavery & Mighell 1992;Makarov et al 2012;Weisz et al 2014;Karachentsev et al 2014Karachentsev et al , 2015a. These are very unlikely to have been quenched as a result of interaction with either the MW or M31.…”

Section: Quenched Dwarfs In the Fieldmentioning

confidence: 99%

Environmental quenching of low-mass field galaxies

Fillingham

Cooper

Boylan-Kolchin

et al. 2018

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

In the local Universe, there is a strong division in the star-forming properties of lowmass galaxies, with star formation largely ubiquitous amongst the field population while satellite systems are predominantly quenched. This dichotomy implies that environmental processes play the dominant role in suppressing star formation within this low-mass regime (M ∼ 10 5.5−8 M ). As shown by observations of the Local Volume, however, there is a non-negligible population of passive systems in the field, which challenges our understanding of quenching at low masses. By applying the satellite quenching models of Fillingham et al. (2015) to subhalo populations in the Exploring the Local Volume In Simulations (ELVIS) suite, we investigate the role of environmental processes in quenching star formation within the nearby field. Using model parameters that reproduce the satellite quenched fraction in the Local Group, we predict a quenched fraction -due solely to environmental effects -of ∼ 0.52 ± 0.26 within 1 < R/R vir < 2 of the Milky Way and M31. This is in good agreement with current observations of the Local Volume and suggests that the majority of the passive field systems observed at these distances are quenched via environmental mechanisms. Beyond 2 R vir , however, dwarf galaxy quenching becomes difficult to explain through an interaction with either the Milky Way or M31, such that more isolated, field dwarfs may be self-quenched as a result of star-formation feedback.

show abstract

“…Theoretical considerations conclude that the cosmological expansion of the Friedmann-Lemaître metric must be negligible at the scale of the galaxy clusters. However recent measurements of the velocity field of nearby galaxies in the vicinity of the Local Group have shown a very linear velocitydistance relation down to about 1 Mpc (i.e., approximately the radius of the Local Group), with a local rate of expansion which coincides with the global Hubble constant [31][32][33]. For very nearby galaxies at distances smaller than 1 Mpc, measurements are more dispersed because of undetermined velocity field components.…”

Section: Cosmological Redshift In Local Bound Systemsmentioning

confidence: 99%

Can the apparent expansion of the universe be attributed to an increasing vacuum refractive index ?

et al. 2018

View full text Add to dashboard Cite

H.A. Wilson, then R.H. Dicke, proposed to describe gravitation by a spatial change of the refractive index of the vacuum around a gravitational mass. Dicke extended this formalism in order to describe the apparent expansion of the universe by a cosmological time dependence of the global vacuum index. In this paper, we develop Dicke's formalism. The metric expansion in standard cosmology (the timedependent scale factor of the Friedmann-Lemaître curved spacetime metric) is replaced by a flat and static Euclidean metric with a change with time of the vacuum index. We show that a vacuum index increasing with time produces both the cosmological redshift and time dilation, and that the predicted evolution of the energy density of the cosmological microwave background is consistent with the standard cosmology. We then show that the type Ia supernovae data, from the joint SDSS-II and SNLS SNe-Ia samples, are well modeled by a vacuum index varying exponentially as n(t) = ex p(t/τ 0 ), where τ 0 = 8.0 +0.2 −0.8 Gyr. The main consequence of this formalism is that the cosmological redshift should affect any atom, with a relative decrease of the energy levels of about −2 10 −18 s −1 . Possibilities for an experimental investigation of this prediction are discussed.

show abstract

The isolated dSph galaxy KKs3 in the local Hubble flow

Cited by 15 publications

References 33 publications

Extending the globular cluster system–halo mass relation to the lowest galaxy masses

Extending the globular cluster system–halo mass relation to the lowest galaxy masses

Environmental quenching of low-mass field galaxies

Can the apparent expansion of the universe be attributed to an increasing vacuum refractive index ?

Contact Info

Product

Resources

About