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Title: Impact of baryonic physics on intrinsic alignments

Abstract

We explore the effects of specific assumptions in the subgrid models of star formation and stellar and AGN feedback on intrinsic alignments of galaxies in cosmological simulations of "MassiveBlack-II" family. Using smaller volume simulations, we explored the parameter space of the subgrid star formation and feedback model and found remarkable robustness of the observable statistical measures to the details of subgrid physics. The one observational probe most sensitive to modeling details is the distribution of misalignment angles. We hypothesize that the amount of angular momentum carried away by the galactic wind is the primary physical quantity that controls the orientation of the stellar distribution. Finally, our results are also consistent with a similar study by the EAGLE simulation team.

Authors:
 [1];  [2];  [3]
  1. Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Carnegie Mellon Univ., Pittsburgh, PA (United States)
  2. Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); The Univ. of Chicago, Chicago, IL (United States)
  3. Univ. of California, Berkeley, CA (United States)
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
OSTI Identifier:
1331125
Report Number(s):
FERMILAB-PUB-16-281-A; arXiv:1607.07140
Journal ID: ISSN 1538-4357; 1477774
Grant/Contract Number:
AC02-07CH11359
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
The Astrophysical Journal (Online)
Additional Journal Information:
Journal Name: The Astrophysical Journal (Online); Journal Volume: 834; Journal Issue: 2; Journal ID: ISSN 1538-4357
Publisher:
Institute of Physics (IOP)
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS; cosmology: theory; galaxies: star formation; gravitational lensing: weak; hydrodynamics; methods: numerical

Citation Formats

Tenneti, Ananth, Gnedin, Nickolay Y., and Feng, Yu. Impact of baryonic physics on intrinsic alignments. United States: N. p., 2017. Web. doi:10.3847/1538-4357/834/2/169.
Tenneti, Ananth, Gnedin, Nickolay Y., & Feng, Yu. Impact of baryonic physics on intrinsic alignments. United States. doi:10.3847/1538-4357/834/2/169.
Tenneti, Ananth, Gnedin, Nickolay Y., and Feng, Yu. Wed . "Impact of baryonic physics on intrinsic alignments". United States. doi:10.3847/1538-4357/834/2/169. https://www.osti.gov/servlets/purl/1331125.
@article{osti_1331125,
title = {Impact of baryonic physics on intrinsic alignments},
author = {Tenneti, Ananth and Gnedin, Nickolay Y. and Feng, Yu},
abstractNote = {We explore the effects of specific assumptions in the subgrid models of star formation and stellar and AGN feedback on intrinsic alignments of galaxies in cosmological simulations of "MassiveBlack-II" family. Using smaller volume simulations, we explored the parameter space of the subgrid star formation and feedback model and found remarkable robustness of the observable statistical measures to the details of subgrid physics. The one observational probe most sensitive to modeling details is the distribution of misalignment angles. We hypothesize that the amount of angular momentum carried away by the galactic wind is the primary physical quantity that controls the orientation of the stellar distribution. Finally, our results are also consistent with a similar study by the EAGLE simulation team.},
doi = {10.3847/1538-4357/834/2/169},
journal = {The Astrophysical Journal (Online)},
number = 2,
volume = 834,
place = {United States},
year = {Wed Jan 11 00:00:00 EST 2017},
month = {Wed Jan 11 00:00:00 EST 2017}
}

Journal Article:
Free Publicly Available Full Text
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Citation Metrics:
Cited by: 2works
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