Characterizing the structure of halo merger trees using a single parameter: the tree entropy

Obreschkow, Danail; Elahi, Pascal J.; Lagos, Claudia del P.; Poulton, R.; Ludlow, Aaron D.

doi:10.1093/mnras/staa445

Cited by 19 publications

(16 citation statements)

References 126 publications

(136 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…But the entropy increase in major mergers can only be detected provided the initial configuration is known. This is what happens in simulations where it is seen, indeed, that major mergers cause an entropy increase with respect to the case of accretion compatible with no increase (Obreschkow et al 2020).…”

Section: Major Mergers and Gaussian Windowsupporting

confidence: 70%

Culminating the peak CUSP to descry the dark side of halos

Salvador-Solé,

Manrique

2021

Preprint

View full text Add to dashboard Cite

The ConflUent System of Peak trajectories (CUSP) is a rigorous formalism in the framework of the peak theory that allows one to derive from first principles and with no free parameters the typical halo properties from the statistics of peaks in the filtered Gaussian random field of density perturbations. The predicted halo mass function, spherically averaged density, velocity dispersion, velocity anisotropy, ellipticity, prolateness and potential profiles, as well as the abundance and number density profiles of accreted and stripped subhalos and diffuse dark matter accurately recover the results of cosmological N -body simulations. CUSP is thus a powerful tool for the calculation, in any desired hierarchical cosmology with Gaussian perturbations, of halo properties beyond the mass, redshift and radial ranges covered by simulations. More importantly, CUSP unravels the origin of the characteristic features of those properties. In the present Paper we culminate its construction. We show that all halo properties but those related with subhalo stripping are independent of the assembly history of those objects, and that the Gaussian is the only smoothing window able to find the finite collapsing patches while properly accounting for the entropy increase produced in major mergers.

show abstract

Section: Major Mergers and Gaussian Windowsupporting

confidence: 70%

Culminating the peak CUSP to descry the dark side of halos

Salvador-Solé,

Manrique

2021

Preprint

View full text Add to dashboard Cite

show abstract

“…But the entropy increase in major mergers can only be detected provided the initial configuration is known. This is what happens in simulations where it is indeed seen that major mergers cause an entropy increase with respect to the case of accretion compatible with no increase (Obreschkow et al 2000).…”

Section: Major Mergers and Gaussian Windowsupporting

confidence: 69%

Culminating the Peak Cusp to Descry the Dark Side of Halos

Salvador-Solé

Manrique

2021

ApJ

View full text Add to dashboard Cite

The ConflUent System of Peak trajectories (CUSP) is a rigorous formalism in the framework of the peak theory that allows one to derive from first principles and no free parameters the typical halo properties from the statistics of peaks in the filtered Gaussian random field of density perturbations. The predicted halo mass function, spherically averaged density, velocity dispersion, velocity anisotropy, ellipticity, prolateness, and potential profiles, as well as the abundance and number density profiles of accreted and stripped subhalos and diffuse dark matter, accurately recover the results of cosmological N-body simulations. CUSP is thus a powerful tool for the calculation, in any desired hierarchical cosmology with Gaussian perturbations, of halo properties beyond the mass, redshift, and radial ranges covered by simulations. More importantly, CUSP unravels the origin of the characteristic features of those properties. In this paper, we culminate its construction. We show that all halo properties but those related to subhalo stripping are independent of the assembly history of those objects, and that the Gaussian is the only smoothing window able to find the finite collapsing patches while properly accounting for the entropy increase produced in major mergers.

show abstract

“…),Weinzirl et al (2009),Gargiulo et al (2015),Pedrosa & Tissera (2015),Irodotou et al (2019),Obreschkow et al (2020), andZanisi et al (2020). Finally, we note that even though…”

mentioning

confidence: 52%

Using angular momentum maps to detect kinematically distinct galactic components

Irodotou

Thomas

2020

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

In this work, we introduce a physically motivated method of performing disc/spheroid decomposition of simulated galaxies, which we apply to the eagle sample. We make use of the healpix package to create Mollweide projections of the angular momentum map of each galaxy’s stellar particles. A number of features arise on the angular momentum space which allows us to decompose galaxies and classify them into different morphological types. We assign stellar particles with angular separation of less/greater than 30° from the densest grid cell on the angular momentum sphere to the disc/spheroid components, respectively. We analyse the spatial distribution for a subsample of galaxies and show that the surface density profiles of the disc and spheroid closely follow an exponential and a Sérsic profile, respectively. In addition discs rotate faster, have smaller velocity dispersions, are younger and are more metal rich than spheroids. Thus, our morphological classification reproduces the observed properties of such systems. Finally, we demonstrate that our method is able to identify a significant population of galaxies with counter-rotating discs and provide a more realistic classification of such systems compared to previous methods.

show abstract

Characterizing the structure of halo merger trees using a single parameter: the tree entropy

Cited by 19 publications

References 126 publications

Culminating the peak CUSP to descry the dark side of halos

Culminating the peak CUSP to descry the dark side of halos

Culminating the Peak Cusp to Descry the Dark Side of Halos

Using angular momentum maps to detect kinematically distinct galactic components

Contact Info

Product

Resources

About