Welcome!

My name is Rolf Kuiper. I am working in the field of computational astrophysics. Currently, I am a Heisenberg-Fellow at the Center for Astronomy (ZAH) within the University of Heidelberg, specifically at the Institute for Theoretical Astrophysics (ITA).

My Team and I are developing novel numerical algorithms for hydrodynamics simulations in the framework of high-performance computing (CPU and GPU). Besides fluid motion, simulations include gravity, magnetic fields, continuum radiation transport, photoionization, phase transitions, chemical evolution, stellar evolution, and dust evolution. We apply these tools to model specific astrophysical processes, focussing on accretion and ejection phenomena, and addressing open research questions within a broad spectrum of topics. Our research interests range from star and planet formation, to stellar physics and stellar feedback, to planetary atmospheres and exoplanets, to the turbulent interstellar medium, to black hole formation, active galactic nuclei, gamma-ray bursts, and to the physics of the early Universe.
For details on our contributions to these reseach fields, please have a look at my Publication records.
For visualizations of our simulation work, check out my YouTube channel!

You are looking for a PhD or Postdoc position? Open positions in our group are commonly posted on the AG Job Register from the German Astronomical Society and the AAS Job Register from the American Astronomical Society. Additonally, feel free to get into Contact with us to chat about further opprtunities!

Are you a student looking for an interesting thesis project, or are you interested in hands-on experience in computational physics? We regularly offer paid mini-research projects and thesis projects on a variety of different topics and numerical methods.
Check out the Vacancies section!

Background Image Credit: André Oliva

Curriculum Vitae

Date Position Institution
06/2021 - today Heisenberg Fellowship Heidelberg University
03/2022 - 04/2022 JSPS Invitational Fellowship Kyoto, Tokyo, and Nagoya University
01/2015 - 05/2021 Emmy Noether Fellowship Tübingen University
08/2013 - 12/2014 Postdoc MPI for Astronomy Heidelberg
01/2013 - 07/2013 Postdoc Tübingen University
11/2012 - 12/2012 Postdoc Heidelberg University
09/2012 - 10/2012 Consulting agreement JPL, CALTECH, Pasadena, USA
09/2011 - 08/2012 Leopoldina Research Fellowship JPL, CALTECH, Pasadena, USA
05/2010 - 08/2011 Postdoc Bonn University
01/2010 - 04/2010 Postdoc MPI for Astronomy Heidelberg
09/2006 - 12/2009 PhD Student MPI for Astronomy Heidelberg
10/2000 - 08/2006 Diploma Student Heidelberg University

Research Group

Rolf Kuiper

(University of Heidelberg)
- Group Leader -

André Oliva

(University of Tübingen)
- PhD Student -

Erick Loría

(University of Costa Rica)
- Master Student -

Gabriel-Dominique Marleau

(University of Tübingen)
- Postdoc -

Tobias Moldenhauer

(University of Tübingen)
- PhD Student -

Mustafa Waqar Syed

(Bilkent University)
- Summer Intern -

Sam Geen

(University of Amsterdam)
- Postdoc -

Lauren Martini

(University of Tübingen)
- Master Student -

Prateek Boga

(SASTRA University)
- Bachelor Student -

Former Members:

• Leandra Krisman (Secretary)
• Jin-Jun Geng (Postdoc)
• Marius Morlock (Master)
• Asmita Bhandare (PhD)
• Shivam Rawat (Student)
• Richard Nies (Bachelor)
• Rahul Joseph (Student)
• Rami Belbeisi (Student)
• Shilpa Bijavara Seshashayana (Student)
• Maria Moroff (Secretary)
• Anders Kölligan (PhD)
• Nathaniel Dylan Kee (Postdoc)
• Nicolas Cimerman (Bachelor & Master)
• Shyam Harimohan Menon (Summer Intern)
• Timothy Hallatt (Summer Intern)
• Oliver Völkel (Bachelor & Master)
• Dominique Meyer (Postdoc)
• Akram Chaalali (Diploma)

Publications

An overview of peer-reviewed research articles can be found in various online databases:

Rolf Kuiper @ NASA/ADS Rolf Kuiper @ arXiv Rolf Kuiper @ ORCiD Rolf Kuiper @ Scopus Rolf Kuiper @ Publons Rolf Kuiper @ Google Scholar

Talks

I am a regular speaker in seminars and colloquia in German research institutes and abroad, on average 1-2 per month. Additionally, my current talk list includes more than 30 contributed conference talks. For brevity, the tables below only list invited talks for public audiences or at international conferences.

Public Talks

Date Event Location Title
2018-11-17 Volkssternwarte Darmstadt e.V. Observatorium Ludwigshöhe, Auf der Ludwigshöhe 196, Darmstadt (Bessungen) Die Geburt stellarer Monster - Über die Entstehung der massereichsten Sterne im Universum
2018-05-04 Astronomische Vereinigung Tübingen Sternwarte Tübingen, Waldhäuser Straße 70, 72076 Tübingen Wie große Sterne entstehen - mit einem internationalen Team beobachtet

Invited Review Talks

Date Event Location Title
2020-01-10 RAS Specialist Discussion Meeting on Radiation-Hydrodynamics London, UK Modeling High-Mass ​Star Formation
2019-05-28 TDLI Workshop on The Radiating Universe in the Era of Multi-Messenger Astrophysics Shanghai, China Review of Modeling High-Mass​ Star Formation
2019-05-20 ISSI Workshop on Star Formation Bern, Switzerland On the Formation and Feedback of High-Mass Stars
2013-06-10 Massive Stars: From alpha to Omega Rhodes, Greece Formation of Massive Stars

Invited Conference Talks

Date Event Location Title
2022 The Physics of Star Formation: From Stellar Cores to Galactic Scales Lyon, France tba
2021-07-12 Puzzles of Star Formation Ringberg Castle, Germany Beuther & Kuiper: What are the differences between high- and low-mass star formation?
2019-09-26 Crete III - Through dark lanes to new stars Crete, Greece Jets and Outflows from Massive Protostars
2019-09-17 Annual Meeting of the German Astronomical Society (AG), Splinter: Star formation and stellar feedback: confronting observations and simulations Stuttgart, Germany Multiplicity of High-mass Star Formation due to Disk Fragmentation
2019-06-13 Zooming in on Star Formation Nafplio, Greece Accretion and Feedback in High-Mass Star Formation
2018-09-04 The Wonders of Star Formation Edinburgh, UK First Hydrodynamics Simulations of Radiation Forces and Photoionization Feedback in Massive Star Formation
2018-07-18 Frontiers of the Physics of Massive Stars Ensenada, Mexico The Formation of Massive (Binary) Stars
2016-07-28 Star Formation in different Environments Quy Nhon, Vietnam Protostellar Outflows and Radiation Feedback from Massive Protostars
2016-04-07 From Stars to Massive Stars Gainesville, Florida The Multi-Physics of Feedback in Massive Star Formation
2015-06-02 Mini-Symposium on Radiative Transfer, Platform for Advanced Scientific Computing Conference Zurich, Switzerland Hybrid Radiation Transport Methods for Star and Planet Formation
2015-03-27 International Workshop on Interstellar Hydrogen Nagoya, Japan The Formation and Feedback of the Most Massive Stars
2014-04-17 Fire Down Below: The Impact of Feedback on Star and Galaxy Formation, KITP Program Gravity‘s Loyal Opposition: The Physics of Star Formation Feedback Santa Barbara, CA, USA Ray-Tracing and Flux-Limited-Diffusion for simulating Stellar Radiation Feedback

Teaching

A textbook example of a Kelvin-Helmholtz Instability, as seen at Tübingen-Sand on December 16th, 2015.

Lectures

Date Format Title Cooperation University
WS 2019/2020 Lecture Astronomy and Astrophysics in tandem with Prof. Santangelo Tübingen
WS 2018/2019 Lecture Astronomy and Astrophysics in tandem with Prof. Santangelo Tübingen
WS 2015/2016 Lecture Applied Numerical Hydrodynamics Tübingen
WS 2013/2014 Lecture Star Formation Tübingen

Seminars

Date Format Title Cooperation University
SS 2020 Seminar Modern Topics in Astronomy & Astrophysics in tandem with Tübingen faculty Tübingen
WS 2019/2020 Seminar Star- and Planet Formation Tübingen
SS 2019 Seminar Modern Topics in Astronomy & Astrophysics in tandem with Tübingen faculty Tübingen
WS 2018/2019 Seminar Star- and Planet Formation Tübingen
SS 2019 Seminar Star- and Planet Formation Tübingen
SS 2018 Seminar Massive Star Formation Tübingen
SS 2017 Seminar Computational Physics in tandem with Dr. Schäfer Tübingen
SS 2017 Seminar Massive Star Formation Tübingen
WS 2016/2017 Seminar Computational Physics in tandem with Prof. Kley Tübingen
WS 2016/2017 Seminar Massive Star Formation Tübingen
SS 2016 Seminar Massive Star Formation Tübingen
WS 2015/2016 Seminar Computational Physics in tandem with Prof. Kley Tübingen

Tutorials

Date Format Title Cooperation University
SS 2008 Tutorial Numerical Fluid Dynamics Lecture by PD Dr. Dullemond Heidelberg
SS 2007 Tutorial Theoretical Electrodynamics Lecture by Prof. Wolschin Heidelberg
SS 2007 Tutorial Theoretical Quantum Mechanics Lecture by Prof. Nachtmann Heidelberg
SS 2007 Tutorial Theoretical Mechanics Lecture by Prof. Wegner Heidelberg
SS 2007 Tutorial Theoretical Electrodynamics Lecture by Prof. Gromes Heidelberg

Workshops

LMEPA 2018
The LMEPA 2018 Workshop covered the formation of low-mass early planetary atmospheres. This small meeting of researchers, working explicitly on simulations of gas accretion onto embedded rocky planets, was organized to flesh out the possible paths to answers of the most important open research questions as well as the techniques necessary to obtain reliable answers.

HMSF 2020
The HMSF 2020 Workshop was a get-together of world-leading researchers on high-mass stellar feedback to present recent results and brainstorm on future directions for modeling the huge variety of feedback effects of high-mass stars on different spatial scales and evolutionary stages.

Vacancies

Are you eager to carry out a project in computational astrophysics? If so, please do not hesitate to contact us and arrange a personal meeting to discuss mutual expectations, potential concerns, and your specific requirements. Let's chat about your favorite topics and methods, and think about the skills you want to employ or what you want to achieve during the project. Anyway, I am sure we will find a project matching your individual needs, skills, and interests!
As a source of inspiration and to give you an idea of the broad spectrum of our project work, please find here some exemplary themes:

Gas-Structure Interaction

Image Credit: Thun, Kuiper et al. (2016)
We employ our numerical framwork to investigate the interaction of solid bodies with surrounding gas in relative motion. Applications of these scenarios include topics of general physics such as the flow pattern behind an airfoil, the turbulent wake behind a ship, or the transition from laminar to turbulent flow as well as astrophysical phenomena such as runaway stars, hypervelocity planets, gravitational friction, or the erosion of dusty bodies.

Accretion

Image Credit: Kuiper & Yorke (2013)
We are interested in accretion physics on various spatial scales and astrophysical environments. The spatial scales of our accretion simulations range from the turbulent interstellar medium to molecular clouds, to proto-stellar cores, to circumstellar disks, down to stellar photospheres. Accreting objects covered range from planets to stars to black holes.

Formation of Planetary Atmospheres

Image Credit: André Oliva
How does a (proto-)planet accrete gas from the circumstellar disk it is embedded in? What is the near-planet flow structure? How massive an atmosphere can the planet accumulate during its growth phase? What are the conditions deciding if an accreting planet grows to a super-Earth, a mini-Neptune, or a Gas Giant? We investigate those and other related research questions in direct numerical simulations of either the global circumstellar disk or the local environment of the accreting planet.

Atmospheric Escape

Movie Credit: Morlock, Kuiper et al. (subm.)
Especially early in their evolution, stars produce a large amount of photons in the extreme ultraviolet (EUV) radiation spectrum in magnetic flare activity. Planets orbiting such stars are impacted by this strong EUV radiation and can lose a substantial fraction of their atmospheres; depending on the distance to the host star, they can even be completely eroded. We model the photoevaporation process of atmospheric escape in order to constrain the observed mass-radius relation of observed exoplanets.

Disk Fragmentation

Movie Credit: Oliva & Kuiper (2020)
How does a circumstellar disk evolve if the gravitational potential is not dominated by the mass of the central host star but the mass of the gaseous accretion disk itself? We investigate the physics of such self-gravitating disks in direct numerical simulations of their formation and evolution. Important research questions in this field include the formation of spectroscopic binary stars, variable accretion and stellar mergers, as well as the characteristics of the observed strong accretion luminosity bursts of young high-mass protostellar objects.

Astrophysical Jets

Movie Credit: Kölligan & Kuiper (2018)
The formation of accretion disks around planets, stars, and black holes is commonly accompanied by the launching of fast energetic jets driven by magneto-centrifugal forces or magnetic pressure. We model the launching, acceleration, collimation, and termination of jets to investigate the physical processes involved in these stages and eventually derive their impact onto their surroundings: How much momentum and energy are injected? Do jets inject turbulence into the surrounding gas? How does collimation change with the size of a jet and its driving physics?

High-Mass Stellar Feedback

Movie Credit: Kuiper & Hosokawa (2018)
High-mass (proto-)stars impact their surroundings by a variety of feedback effects such as protostellar jets and outflows, radiation pressure, photoionization, stellar winds, and eventually supernova explosions. We derive the efficiency of these feedback components in direct numerical simulations of the formation of the most massive stars in the present-day Universe. Our state-of-the-art simulations serve as the basis of follow-up synthetic observation studies to reliably compare the models with observational data.

Photoionization Feedback in the Turbulent Interstellar Medium

Movie Credit: Menon, Federath, & Kuiper (2020)
Massive stars are able to ionize the gas of their surroundings, boosting the gas temperature to about 10,000 K. This bubble of hot gas expands into the surrounding turbulent interstellar medium (ISM), creating the observed morphology of so-called pillars of creation. In direct numerical simulations of the interaction of this ionization front with the ISM gas, we investigate open research questions such as a) How does the photoionization feedback change the turbulent properties of the ISM? Is the newly injected turbulence of compressional or solenoidal nature? b) Can the feedback yield a compression of the ISM gas in such a way to trigger the formation of new stars? c) How important are magnetic fields in this interaction?

Funding

Over the years, our research projects have been supported by a variety of grant funding schemes. We gratefully acknowledge financial support by the following institutions and programmes: