Allen Caldwell How Can Plasma and Proton Beams Be Used in Building Next Generation Particle Accelerators?

Allen Caldwell is Director of the Max Planck Institute for Physics in Garching, Germany and spokesperson for the AWAKE project, a Proton-driven-plasma-wakefield experiment situated at CERN. Before joining the MPI, he spent 15 years at Columbia University researching proton structure and related topics and was the spokesperson for the ZEUS experiment at the electron-proton collider HERA at DESY (German Electron Synchrotron) in Hamburg, Germany. Caldwell is also Honorary Professor at the Technical University of Munich where he teaches courses in probability, statistics and data analysis techniques.

Area of Research

Particle Physics, Plasma Wakefield Acceleration

Allen Caldwell and Chang Liu. "Target Density Normalization for Markov Chain Monte Carlo Algorithms." arXiv preprint arXiv:1410.7149 (2014).  
Allen Caldwell. "Collider Physics at High Energies and Low Luminosities." The European Physical Journal Special Topics 223 (2014): 1139-1143.  
Halina Abramowicz, Iris Abt, Leszek Adamczyk, Marek Adamus, R.L. Aggarwal, Stefano Antonelli, Ozan Arslan, Volodymyr Aushev, Yegor Aushev and Olena Bachynska. "Deep Inelastic Cross-Section Measurements at Large Y with the ZEUS Detector at HERA." Physical Review D 90 (2014): 27.  
Ralph W. Assmann, Richard G. Bingham, Thomas Bohl, Chiara Bracco, Andrew Butterworth, Allen Caldwell, Subhasis Chattopadhyay, Silvia Cipiccia, Eduard Feldbaumer and Ricardo A. Fonseca. "Proton-Driven Plasma Wakefield Acceleration: A Path to the Future of High-Energy Particle Physics." Plasma Physics and Controlled Fusion 56 (2014): 084013.  
ZEUS Collaboration. "Measurement of High-Q2 Deep Inelastic Ep Scattering Cross Sections with a Longitudinally Polarised Positron Beam at HERA." Phys.Rev. D87 5 (2013): 052014.  

since 2012


AWAKE Collaboration

since 2006

Honorary Professor

Technical University of Munich (Technische Universität München)

since 2002


Max Planck Society (more details)

Max Planck Institute for Physics



Columbia University, New York



Nevis Laboratory



ZEUS Collaboration


Deputy Spokesperson

ZEUS Collaboration


Associate Professor

Columbia University, New York



Structure Function Group for ZEUS Experiment


Post Doctoral Research Scientist

Columbia University, New York


PhD in Physics

University of Wisconsin-Madison


Bachelor of Science

Rice University


Chair, ATHENA Review Committee, DESY (2015)

Member, LSC Director Search Committee (2015)

Member, CJPL Scientific Advisory Committee (since 2014)

Member, Financial Oversight Board, Belle-II Collaboration (since 2013)

Supervisory Board, Semiconductor Laboratory of the Max Planck Society Member, IZEST Science Advisory Board (since 2012)

Member, Perspectives Committee of the CPT Section, Max Planck Society (since 2012)

Member, International Review Committee, Institute of Particle Physics (2012)

Organizing Committee, Advanced Accelerator Concepts Workshop (2012)

Visiting Committee for Scientific Programs, Fermi National (2011)

Member, DUSEL Program Advisory Committee (since 2010)

Chair, LHeC Scientific Advisory Committee (since 2008)

Member, Electron-Ion Collider Advisory Committee (since 2008)

Visiting Committee for Scientific Programs, Fermi National (2009)

Review of the Nuclear Science Division, Lawrence Berkeley National Laboratory (2009)

Review of Physics and Astronomy at University College, London (2009)

Project Leader, 'Neutrinos and Beyond' for Sonderforschungsbereich of the DFG (2006-2011)

Max Planck Research Groups Selection Committee (2005-2006, 2006-2007, 2009-2010)

Chair, GERDA Collaboration Board (2004-2011)

Member, Experimental Program Advisory Committee, Stanford Linear Accelerator Center (2002-2006)

Fellow of the American Physical Society (2000)

Alexander von Humboldt Fellowship (1995-1997)


Distinguished Alumnus Award, University of Wisconsin (2012)

© Maximilian Dörrbecker

Max Planck Society

"The Max Planck Society is Germany's most successful research organization. Since its establishment in 1948, no fewer than 18 Nobel laureates have emerged from the ranks of its scientists, putting it on a par with the best and most prestigious research institutions worldwide. The more than 15,000 publications each year in internationally renowned scientific journals are proof of the outstanding research work conducted at Max Planck Institutes – and many of those articles are among the most-cited publications in the relevant field." (Source)


Max Planck Institute for Physics

"What gives matter its mass? This is one of the questions being investigated by scientists at the Max Planck Institute for Physics in Munich. They study the smallest building blocks of matter and how they interact with each other. The behaviour of these building blocks – the quarks, charged leptons and neutrinos – helps them to understand the origin of the universe and its present form. The Institute researchers conduct experiments at the largest particle physics laboratories around the world. These include CERN in Geneva, KEK in Tsukuba (Japan) and DESY in Hamburg. Moreover, they also perform experiments to investigate cosmic radiation on the Canary Island of La Palma and the neutrino experiment in the Gran Sasso underground laboratory in Italy. Theoreticians not only team up with the experimenters to jointly interpret the results of the experiments, but also to develop new theories in order to better characterise our universe." (Source)


The greatest developments in particle physics have been achieved with the help of particle accelerators. To answer open questions on particles, even stronger accelerators are needed but conventional technology encounters limits. The new ‘plasma-wakefield acceleration’ technology is designed to build high performance accelerators that are more compact. As ALLEN CALDWELL explains, the basic idea is to generate a plasma wave that pushes the particles forward. As is shown in this video, energizing the plasma with a proton beam instead of a laser pulse allows to create an electric field of much longer distance.

LT Video Publication DOI:

Proton-Driven Plasma-Wakefield Acceleration

  • Allen Caldwell, Konstantin Lotov, Alexander Pukhov and Frank Simon
  • Nature Physics
  • Published in 2009


Allen Caldwell, Konstantin Lotov, Alexander Pukhov and Frank Simon. "Proton-Driven Plasma-Wakefield Acceleration." Nature Physics 5 (2009): 363-367.