We carry out a systematic investigation of the total mass density profile of massive (Mstar>2e11 Msun) early-type galaxies and its dependence on galactic properties and host halo mass with the aid of a variety of lensing/dynamical data and large mock galaxy catalogs. The latter are produced via semi-empirical models that, by design, are based on just a few basic input assumptions. Galaxies, with measured stellar masses, effective radii and S\'ersic indices, are assigned, via abundance matching relations, host dark matter halos characterized by a typical LCDM profile. Our main results are as follows: (i) In line with observational evidence, our semi-empirical models naturally predict that the total, mass-weighted density slope at the effective radius gamma' is not universal, steepening for more compact and/or massive galaxies, but flattening with increasing host halo mass. (ii) Models characterized by a Salpeter or variable initial mass function and uncontracted dark matter profiles are in good agreement with the data, while a Chabrier initial mass function and/or adiabatic contractions/expansions of the dark matter halos are highly disfavored. (iii) Currently available data on the mass density profiles of very massive galaxies (Mstar>1e12 Msun), with Mhalo>3e14 Msun, favor instead models with a stellar profile flatter than a S\'ersic one in the very inner regions (r<3-5 kpc), and a cored NFW or Einasto dark matter profile with median halo concentration a factor of ~2 or <1.3, respectively, higher than those typically predicted by N-body numerical simulations.

Shankar, F., Sonnenfeld, A., Mamon, G.A., Chae, K., Gavazzi, R., Treu, T., et al. (2017). Revisiting the Bulge–Halo Conspiracy. I. Dependence on Galaxy Properties and Halo Mass. THE ASTROPHYSICAL JOURNAL, 840(1), 1-22 [10.3847/1538-4357/aa66ce].

Revisiting the Bulge–Halo Conspiracy. I. Dependence on Galaxy Properties and Halo Mass

NIPOTI, CARLO;
2017

Abstract

We carry out a systematic investigation of the total mass density profile of massive (Mstar>2e11 Msun) early-type galaxies and its dependence on galactic properties and host halo mass with the aid of a variety of lensing/dynamical data and large mock galaxy catalogs. The latter are produced via semi-empirical models that, by design, are based on just a few basic input assumptions. Galaxies, with measured stellar masses, effective radii and S\'ersic indices, are assigned, via abundance matching relations, host dark matter halos characterized by a typical LCDM profile. Our main results are as follows: (i) In line with observational evidence, our semi-empirical models naturally predict that the total, mass-weighted density slope at the effective radius gamma' is not universal, steepening for more compact and/or massive galaxies, but flattening with increasing host halo mass. (ii) Models characterized by a Salpeter or variable initial mass function and uncontracted dark matter profiles are in good agreement with the data, while a Chabrier initial mass function and/or adiabatic contractions/expansions of the dark matter halos are highly disfavored. (iii) Currently available data on the mass density profiles of very massive galaxies (Mstar>1e12 Msun), with Mhalo>3e14 Msun, favor instead models with a stellar profile flatter than a S\'ersic one in the very inner regions (r<3-5 kpc), and a cored NFW or Einasto dark matter profile with median halo concentration a factor of ~2 or <1.3, respectively, higher than those typically predicted by N-body numerical simulations.
2017
Shankar, F., Sonnenfeld, A., Mamon, G.A., Chae, K., Gavazzi, R., Treu, T., et al. (2017). Revisiting the Bulge–Halo Conspiracy. I. Dependence on Galaxy Properties and Halo Mass. THE ASTROPHYSICAL JOURNAL, 840(1), 1-22 [10.3847/1538-4357/aa66ce].
Shankar, Francesco; Sonnenfeld, Alessandro; Mamon, Gary A.; Chae, Kyu-Hyun; Gavazzi, Raphael; Treu, Tommaso; Diemer, Benedikt; Nipoti, Carlo; Buchan, ...espandi
File in questo prodotto:
Eventuali allegati, non sono esposti

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11585/591353
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 34
  • ???jsp.display-item.citation.isi??? 23
social impact