@article{chen_dynamical_2021,
	title = {Dynamical {Friction} {Modeling} of {Massive} {Black} {Holes} in {Cosmological} {Simulations} and {Effects} on {Merger} {Rate} {Predictions}},
	volume = {2104},
	url = {http://adsabs.harvard.edu/abs/2021arXiv210400021C},
	abstract = {In this work we establish and test methods for implementing dynamical 
friction for massive black hole pairs that form in large volume
cosmological hydrodynamical simulations which include galaxy formation
and black hole growth. We verify our models and parameters both for
individual black hole dynamics and for the black hole population in
cosmological volumes. Using our model of dynamical friction (DF) from
collisionless particles, black holes can effectively sink close to the
galaxy center, provided that the black hole's dynamical mass is at least
twice that of the lowest mass resolution particles in the simulation.
Gas drag also plays a role in assisting the black holes' orbital decay,
but it is typically less effective than that from collisionless
particles, especially after the first billion years of the black hole's
evolution. DF from gas becomes less than \$1{\textbackslash}\%\$ of DF from collisionless
particles for BH masses \${\textgreater} 10{\textasciicircum}\{7\}\$ M\$\_\{{\textbackslash}odot\}\$. Using our best DF
model, we calculate the merger rate down to \$z=1.1\$ using an \$L\_\{\vphantom{\}}{\textbackslash}rm
box\vphantom{\{}\}=35\$ Mpc\$/h\$ simulation box. We predict \${\textbackslash}sim 2\$ mergers per year
for \$z{\textgreater}1.1\$ peaking at \$z{\textbackslash}sim 2\$. These merger rates are within the
range obtained in previous work using similar-resolution hydro-dynamical
simulations. We show that the rate is enhanced by factor of \${\textbackslash}sim 2\$
when DF is taken into account in the simulations compared to the no-DF
run. This is due to \${\textgreater}40{\textbackslash}\%\$ more black holes reaching the center of
their host halo when DF is added.},
	urldate = {2021-04-08},
	journal = {arXiv e-prints},
	author = {Chen, Nianyi and Ni, Yueying and Tremmel, Michael and Di Matteo, Tiziana and Bird, Simeon and DeGraf, Colin and Feng, Yu},
	month = mar,
	year = {2021},
	keywords = {Astrophysics - Astrophysics of Galaxies},
	pages = {arXiv:2104.00021},
}

{"_id":"ZhSAozL4waSMbQk79","bibbaseid":"chen-ni-tremmel-dimatteo-bird-degraf-feng-dynamicalfrictionmodelingofmassiveblackholesincosmologicalsimulationsandeffectsonmergerratepredictions-2021","author_short":["Chen, N.","Ni, Y.","Tremmel, M.","Di Matteo, T.","Bird, S.","DeGraf, C.","Feng, Y."],"bibdata":{"bibtype":"article","type":"article","title":"Dynamical Friction Modeling of Massive Black Holes in Cosmological Simulations and Effects on Merger Rate Predictions","volume":"2104","url":"http://adsabs.harvard.edu/abs/2021arXiv210400021C","abstract":"In this work we establish and test methods for implementing dynamical friction for massive black hole pairs that form in large volume cosmological hydrodynamical simulations which include galaxy formation and black hole growth. We verify our models and parameters both for individual black hole dynamics and for the black hole population in cosmological volumes. Using our model of dynamical friction (DF) from collisionless particles, black holes can effectively sink close to the galaxy center, provided that the black hole's dynamical mass is at least twice that of the lowest mass resolution particles in the simulation. Gas drag also plays a role in assisting the black holes' orbital decay, but it is typically less effective than that from collisionless particles, especially after the first billion years of the black hole's evolution. DF from gas becomes less than \\$1{\\textbackslash}%\\$ of DF from collisionless particles for BH masses \\${\\textgreater} 10{\\textasciicircum}\\{7\\}\\$ M\\$_\\{{\\textbackslash}odot\\}\\$. Using our best DF model, we calculate the merger rate down to \\$z=1.1\\$ using an \\$L_\\{p̌hantom{\\}}{\\textbackslash}rm boxp̌hantom{\\{}\\}=35\\$ Mpc\\$/h\\$ simulation box. We predict \\${\\textbackslash}sim 2\\$ mergers per year for \\$z{\\textgreater}1.1\\$ peaking at \\$z{\\textbackslash}sim 2\\$. These merger rates are within the range obtained in previous work using similar-resolution hydro-dynamical simulations. We show that the rate is enhanced by factor of \\${\\textbackslash}sim 2\\$ when DF is taken into account in the simulations compared to the no-DF run. This is due to \\${\\textgreater}40{\\textbackslash}%\\$ more black holes reaching the center of their host halo when DF is added.","urldate":"2021-04-08","journal":"arXiv e-prints","author":[{"propositions":[],"lastnames":["Chen"],"firstnames":["Nianyi"],"suffixes":[]},{"propositions":[],"lastnames":["Ni"],"firstnames":["Yueying"],"suffixes":[]},{"propositions":[],"lastnames":["Tremmel"],"firstnames":["Michael"],"suffixes":[]},{"propositions":[],"lastnames":["Di","Matteo"],"firstnames":["Tiziana"],"suffixes":[]},{"propositions":[],"lastnames":["Bird"],"firstnames":["Simeon"],"suffixes":[]},{"propositions":[],"lastnames":["DeGraf"],"firstnames":["Colin"],"suffixes":[]},{"propositions":[],"lastnames":["Feng"],"firstnames":["Yu"],"suffixes":[]}],"month":"March","year":"2021","keywords":"Astrophysics - Astrophysics of Galaxies","pages":"arXiv:2104.00021","bibtex":"@article{chen_dynamical_2021,\n\ttitle = {Dynamical {Friction} {Modeling} of {Massive} {Black} {Holes} in {Cosmological} {Simulations} and {Effects} on {Merger} {Rate} {Predictions}},\n\tvolume = {2104},\n\turl = {http://adsabs.harvard.edu/abs/2021arXiv210400021C},\n\tabstract = {In this work we establish and test methods for implementing dynamical \nfriction for massive black hole pairs that form in large volume\ncosmological hydrodynamical simulations which include galaxy formation\nand black hole growth. We verify our models and parameters both for\nindividual black hole dynamics and for the black hole population in\ncosmological volumes. Using our model of dynamical friction (DF) from\ncollisionless particles, black holes can effectively sink close to the\ngalaxy center, provided that the black hole's dynamical mass is at least\ntwice that of the lowest mass resolution particles in the simulation.\nGas drag also plays a role in assisting the black holes' orbital decay,\nbut it is typically less effective than that from collisionless\nparticles, especially after the first billion years of the black hole's\nevolution. DF from gas becomes less than \\$1{\\textbackslash}\\%\\$ of DF from collisionless\nparticles for BH masses \\${\\textgreater} 10{\\textasciicircum}\\{7\\}\\$ M\\$\\_\\{{\\textbackslash}odot\\}\\$. Using our best DF\nmodel, we calculate the merger rate down to \\$z=1.1\\$ using an \\$L\\_\\{\\vphantom{\\}}{\\textbackslash}rm\nbox\\vphantom{\\{}\\}=35\\$ Mpc\\$/h\\$ simulation box. We predict \\${\\textbackslash}sim 2\\$ mergers per year\nfor \\$z{\\textgreater}1.1\\$ peaking at \\$z{\\textbackslash}sim 2\\$. These merger rates are within the\nrange obtained in previous work using similar-resolution hydro-dynamical\nsimulations. We show that the rate is enhanced by factor of \\${\\textbackslash}sim 2\\$\nwhen DF is taken into account in the simulations compared to the no-DF\nrun. This is due to \\${\\textgreater}40{\\textbackslash}\\%\\$ more black holes reaching the center of\ntheir host halo when DF is added.},\n\turldate = {2021-04-08},\n\tjournal = {arXiv e-prints},\n\tauthor = {Chen, Nianyi and Ni, Yueying and Tremmel, Michael and Di Matteo, Tiziana and Bird, Simeon and DeGraf, Colin and Feng, Yu},\n\tmonth = mar,\n\tyear = {2021},\n\tkeywords = {Astrophysics - Astrophysics of Galaxies},\n\tpages = {arXiv:2104.00021},\n}\n\n","author_short":["Chen, N.","Ni, Y.","Tremmel, M.","Di Matteo, T.","Bird, S.","DeGraf, C.","Feng, Y."],"key":"chen_dynamical_2021","id":"chen_dynamical_2021","bibbaseid":"chen-ni-tremmel-dimatteo-bird-degraf-feng-dynamicalfrictionmodelingofmassiveblackholesincosmologicalsimulationsandeffectsonmergerratepredictions-2021","role":"author","urls":{"Paper":"http://adsabs.harvard.edu/abs/2021arXiv210400021C"},"keyword":["Astrophysics - Astrophysics of Galaxies"],"metadata":{"authorlinks":{}}},"bibtype":"article","biburl":"https://bibbase.org/zotero/polyphant","dataSources":["7gvjSdWrEu7z5vjjj"],"keywords":["astrophysics - astrophysics of galaxies"],"search_terms":["dynamical","friction","modeling","massive","black","holes","cosmological","simulations","effects","merger","rate","predictions","chen","ni","tremmel","di matteo","bird","degraf","feng"],"title":"Dynamical Friction Modeling of Massive Black Holes in Cosmological Simulations and Effects on Merger Rate Predictions","year":2021}