Astronomy and Astrophysics – Astrophysics – Cosmology and Extragalactic Astrophysics
Scientific paper
2010-07-09
Astronomy and Astrophysics
Astrophysics
Cosmology and Extragalactic Astrophysics
22 pages, 20 figures, minor revisions, accepted for publication in MNRAS
Scientific paper
We investigate the properties of triply ionized Carbon (CIV) in the Intergalactic Medium using a set of high-resolution and large box-size cosmological hydrodynamic simulations of a $\Lambda$CDM model. We rely on a modification of the GADGET-2 code that self-consistently follows the metal enrichment mechanism by means of a detailed chemical evolution model. We focus on several numerical implementations of galactic feedback: galactic winds in the energy driven and momentum driven prescriptions and Active Galactic Nuclei (AGN) powered by gas accretion onto massive black holes. We extract mock IGM transmission spectra in neutral hydrogen (HI) and CIV and perform Voigt profile fitting. The results are then compared with high-resolution quasar (QSO) spectra obtained with the UVES spectrograph at the VLT and the HIRES spectrograph at Keck. We find that feedback has little impact on statistics related to the neutral hydrogen, while CIV is more affected by galactic winds and/or AGN feedback. When the same analysis is performed over observed and simulated CIV lines, we find reasonables good agreement between data and simulations over the column density range $N_{\rm CIV}=10^{12.5-15}$ cm$^{-2}$. Also the CIV line-widths distribution appears to be in agreement with the observed values, while the HI Doppler parameters, $b_{\rm HI}$, are in general too large showing that the diffuse cosmic web is heated more than what is inferred by observations. The simulation without feedback fails in reproducing the CIV systems at high column densities at all redshift, while the AGN feedback case agrees with observations only at $z<3$, when this form of feedback is particularly effective. We also present scatter plots in the $b-N$ and in the $N_{\rm CIV}-N_{\rm HI}$ planes, showing that there is rough agreement between observations and simulations only when feedback is taken into account.
Borgani Stefano
Calura Francesco
Cristiani Stefano
D'Odorico Valentina
Tescari Edoardo
No associations
LandOfFree
Cosmic evolution of the CIV in high-resolution hydrodynamic simulations does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Cosmic evolution of the CIV in high-resolution hydrodynamic simulations, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Cosmic evolution of the CIV in high-resolution hydrodynamic simulations will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-645565