Research Homepage of Christian D. Ott
Welcome!
I am a computational/theoretical astrophysicist in TAPIR, which is part of the
Walter Burke Institute for
Theoretical Physics at Caltech, working at the interface of
numerical relativity, nuclear/neutrino astrophysics, and
gravitationalwave physics. My current primary research interests are
(1) explosions of massive stars in corecollapse supernovae and long
gammaray bursts and their multimessenger signatures in neutrinos,
gravitational waves, and photons, (2) the formation of stellar mass
and supermassive black holes, and (3) binary black hole and neutron
star mergers.
I lead the Caltech portion of
the Simulating eXtreme Spacetimes
(SXS) collaboration and also work closely with
the Einstein Toolkit team.
Another line of my research is
concerned with the observation and interpretation of gravitational
waves from astrophysical sources. I was involved in the LIGO Scientific
Collaboration and contributed to the first direct detection of gravitational
waves.
I am presently leading an NSF CAREER project in Gravitational
Physics. I was a 20122014 Alfred P. Sloan Research Fellow.
Trainees/Mentees that won national postdoctoral
fellowships:
Evan O'Connor (Junior Faculty, Stockholm University 2016;
Hubble Fellowship 2014; Caltech PhD 2012), Christine Corbett Moran
(NSF Fellowship 2015), Philipp Mösta (Einstein Fellowship 2015),
Christian Reisswig (Einstein Fellowship 2012), Luke Roberts (Einstein
Fellowship 2013).
Postdocs shipped off to faculty positions:
Luke Roberts (Michigan State University, 2016),
Sebastiano Bernuzzi (University of Parma, 2015),
Sean Couch (Michigan State University, 2015),
Ernazar Abdikamalov (Nazarbayev University, Kasachstan, 2014)
Follow me on Twitter:
Read my blog: Blowing Up Stars
Check out some of my talks on: SlideShare
stellarcollapse.org  a community portal for stellar collapse, supernovae, and compact objects
youtube.com/sxscollaboration  SXS Collaboration YouTube Channel
blackholes.org  SXS Collaboration Website
The Team: Current Students & Postdocs
New Stuff (in quasichronological order)
 2016/04/22 Sherwood Richers wins 2016 Blue Waters Fellowship!
Congrats to
Sherwood! Very well deserved! Blue
Waters is the National Science Foundation funded leadership
US computing facility operated by
the National Center for
Supercomputing Allocations (NCSA) at the University of
Illinois. The Blue Waters Fellowship is a nationally competed,
highlyselective graduate fellowship that provides a year of
graduate research assistant support and computer time on Blue
Waters.
Sherwood holds a 20122016 DOE Computational Science
Graduate Fellowship and the Blue Waters Fellowship will support
his thesis research on neutrino transport in 3D corecollapse
supernovae and neutron star mergers in the 2016/17 academic
year. 

 2015/08/21 MICRA 2015

I coorganized the 4th Microphysics in Computational
Relativistic Astrophysics Workshop (MICRA 2015)
at Stockholm University, August 1721, 2015.
http://compactmerger.astro.su.se/MICRA2015/
Chris Pethick and I started the MICRA series of workshops in 2009 to
bring together people from the numerical relativity/computational
astro community and from the nuclear physics community. The goal of
this is to increase communication and collaboration between these
communities in order to bring more realistic microphysics (nuclear
physics, neutrino physics etc.) to simulations.
Caltech was well represented: Grad students Sherwood Richers and Jonas
Lippuner, postdoc David Radice, and I attended. It was also great to
catch up with former group members Roland Haas (AEI), Philipp Mösta (Berkeley), Sebastiano Bernuzzi (Parma), and Evan O'Connor (Hubble Fellow, NC State).

 2015/07/12 School is out! CGWAS 2015 is over!
60 students from 11 countries had a great time thanks to 16 lecturers and 17 dedicated local colleagues at Caltech who helped make CGWAS 2015 happen.
Lecture slides/notes, exercises, and solutions are available on the
CGWAS website.
 2015/06/21 Caltech Gravitational Wave Astrophysics School 2015
 2015/05/21 Graduate student Jonathan Blackman is
named the Caltech PMA Garmire Scholar 2015!
 2015/04/10 Hannah Klion wins Department of Energy
Computational Science Graduate Fellowship
(CSGF)!
Congrats to Hannah! Hannah is a senior in the physics program at
Caltech and has been working with us since her Freshman year. Her
research is on rotating core collapse and gravitational wave emission
from its postbounce ringdown phase. Hannah will take her CSGF to one
of the schools she is currently considering for graduate school and we
hope to continue to collaborate with her in the future!
 2015/03/28 Two podcasts feature me on stellar collapse and supernova explosions
The Star Spot  Episode 73: Things that explode, with Christian Ott
Physics Central  Physics Buzz Blog Podcast: Supernova Neutrinos
 2015/01/24 Public Lecture at Toronto's Astronomy & Space Exploration Society Symposium.

I had the pleasure of joining the Astronomy & Space Exploration Society for their 12th Annual Symposium at the University of Toronto on January 23, 2015. ASX is an undergraduaterun organization that organizes regular seminars on topics related to astronomy and space and they put together their yearly symposium that is always under a special theme. This year's symposium had the theme "Stellar Graveyard"  of course that's a topic I have something to say about. I gave a lecture on The Theory of Stellar Death and Explosion. The symposium was a lot of fun! A broad and diverse audience of about 450 people attended and most stayed until the end of my talk (at 10:15 pm!).

 2014/03/05 Magnetorotational CoreCollapse Supernovae in 3D: Mösta et al. 2014, arXiv:1403.1230

What drives hypernovae, extreme supernova explosions that have
many times the explosion energy of a gardenvariety supernova from a
massive star?
Detailed simulations show that the standard mechanism for
corecollapse supernovae  the neutrino mechanism  seems to lack
the efficiency to drive such powerful explosions.
A possibly more powerful alternative could be
the magnetorotational mechanism. In this scenario, rapid
rotation (a protoneutron star with a millisecond spin period) in
combination with a very strong toroidal magnetic field
(10^{15}10^{16} G) are expected to push out
energetic bipolar outflows along the axis of rotation.
Our team has just completed the first set of full 3D,
dynamicalspacetime GRmagnetohydrodynamic simulations of
magnetorotational corecollapse supernovae. This work was led by postdoc
Philipp Mösta
and grad
student Sherwood
Richers (DOE Computational Science Graduate Fellow) made important
contributions.
In collaboration with other team members, Philipp and
Sherwood showed that the configuration that leads to strong jets in
axisymmetry is unstable in 3D to an MHD kink instability,
leading to a spiral deformation of the outflow. The volume rendering
the left shows the entropy distribution at some 160 milliseconds after
core bounce. Red indicates high entropy (about >10
k_{B}/baryon), blue low entropy (a few
k_{B}/baryon). The vertical axis is the vertical and the scale
is 1600 km. Instead of a clean jet, two huge lobes develop that move
out secularly as the protoneutron star pushes spiral streams of out
hot, highly magnetized plasma into polar regions.
Interested in learning more? Check out
our paper and the movies that
go along with it stellarcollapse.org/3dgrmhd.
The simulations used of the opensource Einstein Toolkit and additional source code and input parameters needed to reproduce our simulations can be found at stellarcollapse.org/3dgrmhd.

 2013/07/27 Caltech Gravitational Wave Astrophysics School 2013
A week of exciting lectures, two parties and a field trip to Mt. Wilson Observatory (see group picture in front of the 100inch Hooker telescope!) is over. We'll do it again in two years!
 2013/07/01 Congratulations Dr. Jeff Kaplan!
PhD offspring #2! Jeff will join the US STEM workforce in finance.
Older News
Some Current Projects and Collaborations

My team at Caltech, which is part of the Simulating eXtreme Spacetimes
collaboration, is working on full 3D simulations of corecollapse
supernovae with the ultimate goal of connecting precollapse conditions
to the various possible outcomes of stellar collapse and their multimessenger
(photons, neutrinos, gravitational waves) signatures.

I am a member of the Einstein Toolkit
that aims to provide well tested and documented opensource
simulation codes to the numerical relativity and astrophysics modeling
community.

I very strongly believe in open source and strive to make my
simulation codes and input physics publically available. Most of my 3D
supernova simulation tools are already public and part of the
Einstein Toolkit
. My former graduate student Evan O'Connor's code GR1D (see the GR1D code paper) is also available as open
source from our stellarcollapse.org
website. There we also host finitetemperature nuclear equation of state tables
and table reader/interpolation code.
 I am trying to
understand how combined neutrino and gravitational wave observations
from the next galactic corecollapse supernova may be used to
constrain supernova physics and fundamental physics.

With the CaltechCornellCITAWSU Simulating eXtreme Spacetimes (SXS)
collaboration I am studying the merger of neutron star  neutron
star and black hole  neutron star binaries. This research is primarily
funded by the Sherman Fairchild Foundation.

I work with the Princeton supernova group (led by
Adam Burrows) on various topics in
corecollapse supernova theory. The current focus is 1D and multiD neutrino
transport using Monte Carlo techniques.
Publications
(Complete ADS list),
(ADS shortauthor list only [no LIGO papers]),
Recent Short Author List Work (since 2013):

S. Bernuzzi, D. Radice, C. D. Ott, L. Roberts, P. Mösta,
F. Galeazzi, "How Loud Are Neutron Star Mergers,"
Phys. Rev. D 94, 024023 (2016),
(ads).

R. Haas, C. D. Ott, B. Szilagyi, J. D. Kaplan, J. Lippuner, M. Scheel, K. Barkett, C. Muhlberger, T. Dietrich, M. Duez, F. Foucart, H. Pfeiffer, L. Kidder, S. Teukolsky, "Simulations of inspiraling and merging double neutron stars using the Spectral Einstein Code," Phys. Rev. D. 93, 124062 (2016) (ads).

L. Robers, C. D. Ott, R. Haas, E. P. O'Connor, P. Diener, E. Schnetter, "General Relativistic ThreeDimensional MultiGroup Neutrino RadiationHydrodynamics Simulations of CoreCollapse Supernovae," accepted for publication in ApJ (2016) (arXiv/ads).

D. Gerosa, U. Sperhake, and C. D. Ott, "Numerical Simulations of
Stellar Collapse in ScalarTensor Theories of Gravity,"
Class. Quantum Grav. 33, 135002 (2016)
(ads).

L. Roberts, J. Lippuner, M. Duez, J. Faber, F. Foucart,
J. Lombardi, S. Ning, C. D. Ott, M. Ponce, " The Influence of
Neutrinos on rProcess Nucleosynthesis in the Ejecta of Black
HoleNeutron Star Mergers," submitted to MNRAS,
(arXiv/ads).
 V. Morozova, A. L. Piro, C. D. Ott, M. Renzo, "Numerical Modeling of the Early Light Curves of Type IIP Supernovae," accepted for publication in ApJ, (ads).

D. Radice, S. Bernuzzi, C. D. Ott, "The OneArmed Spiral Instability in Neutron Star Mergers and its Detectability in Gravitational Waves," submitted to PRD, (arXiv/ads).

D. Radice, F. Galeazzi, J. Lippuner, L. Roberts, C. D. Ott,
L. Rezzolla, "Dynamical Mass Ejection from Binary Neutron Star
Mergers," MNRAS 460, 3255 (2016),
(ads).

D. Radice, C. D. Ott, E. Abdikamalov, S. M. Couch, R. Haas, E. Schnetter, "NeutrinoDriven Convection in CoreCollapse Supernovae: HighResolution Simulations," ApJ 820, 76 (2016), (ads).

S. Gossan, P. Sutton, A. Stuver, M. Zanolin, K. Gill, C. D. Ott,
"Observing Gravitational Waves from CoreCollapse Supernovae in
the Advanced Detector Era,", Phys. Rev. D 93, 042002 (2016),
(ads).

K. Barkett, M. Scheel, R. Haas, C. D. Ott, S. Bernuzzi, D. Brown,
B. Szilagyi, J. Kaplan, J. Lippuner, C. Muhlberger, F. Foucart,
M. Duez, "Gravitational waveforms for neutron star binaries from
binary black hole simulations," Phys. Rev. D 93, 044064 (2016),
(ads).

F. Foucart, R. Haas, M. Duez, E. O'Connor, C. D. Ott, L. Roberts,
L. Kidder, J. Lippuner, H. Pfeiffer, M. Scheel, "Low mass binary
neutron star mergers : gravitational waves and neutrino emission,"
Phys. Rev. D 93, 044019 (2016),
(ads).

P. Mösta, C. D. Ott, D. Radice, L. Roberts, E. Schnetter,
R. Haas, "A largescale Dynamo and Magnetoturbulence in rapidly
rotating CoreCollapse Supernovae," Nature 528, 376 (2015),
(ads).

V. Morozova, A. L. Piro, M. Renzo, C. D. Ott, D. Clausen, S. M. Couch, J. Ellis, L. F. Roberts, "Light Curves of CoreCollapse Supernovae with Substantial Mass Loss using the New OpenSource SuperNova Explosion Code (SNEC)," ApJ 814, 63 (2015), (ads).

S. Richers, D. Kasen, E. O'Connor, R. Fernandez, C. D. Ott, "Monte Carlo Neutrino Transport Through Remnant Disks from Neutron Star Mergers," ApJ 813, 38 (2015), (ads).

E. Abdikamalov, C. D. Ott, D. Radice, L. F. Roberts, R. Haas, C. Reisswig, P. Moesta, H. Klion, and E. Schnetter, "Neutrinodriven Turbulent Convection and Standing Accretion Shock Instability in ThreeDimensional CoreCollapse Supernovae," ApJ 808, 70 (2015), (ads).

J. Fuller and C. D. Ott, "Dark Matterinduced Collapse of Neutron Stars: A Possible Link Between Fast Radio Bursts and the Missing Pulsar Problem," MNRAS 450, L71 (2015), (ads).

J. Fuller, H. Klion, E. Abdkikamalov and C. D. Ott, "Supernova seismology: gravitational wave signatures of rapidly rotating core collapse," MNRAS 450, 414 (2015), (ads).

D. Radice, S. M. Couch, and C. D. Ott, "Implicit large eddy simulations of anisotropic weakly compressible turbulence with application to corecollapse supernovae," Computational Astrophysics and Cosmology 2:7 (2015), (ads).

F. Foucart, E. O'Connor, L. Roberts, M. Duez, R. Haas, L. Kidder, C. D. Ott, H. Pfeiffer, M. Scheel, B. Szilagyi, "Postmerger evolution of a neutron starblack hole binary with neutrino transport,", PRD 91, 120421 (2015), (ads).

D. Clausen, A. L. Piro, and C. D. Ott, "The Black Hole Formation Probability," ApJ 799, 190 (2015), (ads).

S. M. Couch and C. D. Ott, "The Role of Turbulence in NeutrinoDriven CoreCollapse Supernova Explosions," ApJ 799, 12 (2015), (ads).

E. Abdikamalov, S. Gossan, A. DeMaio, C. D. Ott, "Measuring the Angular Momentum Distribution in CoreCollapse Supernova Progenitors with Gravitational Waves," PRD 90, 044001 (2014), (ads).

F. Foucart, B. Deaton, M. Duez, E. O'Connor, C. D. Ott, R. Haas, L. Kidder, H. Pfeiffer, M. Scheel, B. Szilagyi, "Neutron starblack hole mergers with a nuclear equation of state and neutrino cooling: Dependence in the binary parameters,", Phys. Rev. D. 90, 024026 (2014), (ads).

J. D. Kaplan, C. D. Ott, E. P. O'Connor, K. Kiuchi, L. Roberts, M. Duez, "The Influence of Thermal Pressure on Equilibrium Models of Hypermassive Neutron Star Merger Remnants," ApJ 790, 19 (2014), (ads).

W. Engels, R. Frey, and C. D. Ott, "Multivariate Regression Analysis of Gravitational Waves from Rotating Core Collapse," PRD 90, 124026 (2014), (ads).

C. Muhlberger, F. H. Nouri, M. Duez, F. Foucart, L. Kidder, C. D. Ott, M. Scheel, B. Szilagyi, and S. Teukolsky, "Magnetic effects on the lowT/W instability in differentially rotating neutron stars," PRD 90, 104014 (2014), (ads).

P. Mösta, S. Richers, C. D. Ott, R. Haas, A. L. Piro, K. Boydstun, E. Abdikamalov, C. Reisswig, E. Schnetter, "Magnetorotational CoreCollapse Supernovae in Three Dimensions," ApJ, 785, L29 (2014), (ads).

P. Mösta, B. Mundim, J. Faber, R. Haas, S. Noble, T. Bode, F. Löffler, C. D. Ott, C. Reisswig, E. Schnetter, "GRHydro: A new open source generalrelativistic magnetohydrodynamics code for the Einstein Toolkit," CQG 31, 015005 (2014), (ads).

S. M. Couch and C. D. Ott, "Revival of the Stalled Corecollapse Supernova Shock Triggered by Precollapse Asphericity in the Progenitor Star," ApJ 778, L7 (2013),(ads).

C. Reisswig, C. D. Ott, E. Abdikamalov, R. Haas, P. Moesta, E. Schnetter, "Formation and Coalescence of Cosmological Supermassive Black Hole Binaries in Supermassive Star Collapse," PRL 111, 151101 (2013), (ads).

M. B. Deaton, M. Duez, F. Foucart, E. O'Connor, C. D. Ott, L. Kidder, C. Muhlberger, M. Scheel, B. Szilagyi, "Black HoleNeutron Star Mergers with a Hot Nuclear Equation of State: Outflow and NeutrinoCooled Disk for a LowMass, HighSpin Case," ApJ 776, 47 (2013), (ads).

F. Foucart, M. B. Deaton, M. Duez, L. Kidder, I. MacDonald, C. D. Ott, H. Pfeiffer, M. Scheel, B. Szilagyi, S. Teukolsky, "Blackholeneutronstar mergers at realistic mass ratios: Equation of state and spin orientation effects," Phys. Rev. D. 87, 084006 (2013), (ads).

C. Reisswig, R. Haas, C. D. Ott, E. Abdikamalov, P. Moesta, D. Pollney, and E. Schnetter,
"ThreeDimensional GeneralRelativistic Hydrodynamic Simulations of Binary Neutron Star Coalescence and Stellar Collapse with Multipatch Grids," Phys. Rev. D. 87, 064023 (2013), (ads)

C. D. Ott, E. Abdkimalov, P. Moesta, R. Haas, S. Drasco, E. O'Connor, C. Reisswig, C. Meakin, and E. Schnetter, "GeneralRelativistic Simulations of ThreeDimensional CoreCollapse Supernovae," ApJ 768, 115 (2013), (ads).

O. Korobkin, E. Abdikamalov, N. Stergioulas, E. Schnetter, B. Zink, S. Rosswog, and C. D. Ott, "The runaway instability in generalrelativistic accretion disks," MNRAS, 431, 349 (2013), (ads).

D. Radice, E. Abdikamalov, L. Rezzolla, and C. D. Ott, "A New Spherical Harmonics Scheme for MultiDimensional Radiation Transport I: Static Matter Configurations," J. Comp. Phys. 242, 648 (2013), (ads).

E. O'Connor and C. D. Ott, "The Progenitor Dependence of the Preexplosion Neutrino Emission in CoreCollapse Supernovae," ApJ 762, 126 (2013), (ads).