Tobias Toll

Tobias Toll
Assistant Professor
Indian Institute of Technology Delhi
Hauz khas, New Delhi-110016
Room No. MS 440

Research interest:

I investigate the non-linear strong force, mediated by gluons. The strong force is described by Quantum Chromo Dynamics (QCD) which is an integral part of the Standard Model of Particle Physics. However, for systems of gluons which are very large (>1 fm) or very dense, the differential equations of QCD become highly non-linear and therefore difficult to solve. In these regions we must instead rely on phenomenological models which we fit to measured data. I am also interested in how we may measure the fluctuations of gluons, since these particles exist in nature purely as virtual vacuum fluctuations.

One laboratory where these phenomena can be observed and measured to great precision is the Electron-Ion Collider (EIC). It is at the moment being developed in the US and will start to take data in the 20s. My work is focus on developing phenomenological models of the non-linear strong force, and fluctuations, and implementing them into so called Event Generators, computer programs which simulate event-by-event particle collisions. I have developed, in collaboration with Thomas Ullrich, the event generator Sartre. This program simulates some of the crucial measurements at the EIC, and this simulation is then used to design the interaction region and the detectors located around the collision points of the EIC so that we may extract the interesting data.

I am particularly interested in so called diffractive processes, where the electron interacts with a nucleus through the strong force but without exchange of quantum numbers. It turns out that these processes are especially sensitive to high density gluon phenomena, as well as large system phenomena and gluon fluctuations. There is a small but very active community around the world working on the phenomenology of these processes, using data from HERA to tune our models, and use them to describe some current measurements at the Large Hadron Collider, in order to design the EIC.

Previous Research Experience:

  • 2018-present: Assistant Professor, IIT Delhi.
  • 2014-2018: Assistant Professor, Shiv Nadar University, UP
  • 2010-2014: Postdoc, Brookhaven Lab, New York, USA
  • 2005-2010: PhD, DESY, Hamburg, Germany
  • 2000-2005: Bachelor/Master, Lund University, Sweden

Selected Publications:

  • Exclusive diffractive processes in electron-ion collisions
    Tobias Toll, Thomas Ullrich (Brookhaven). 2012.
    Phys.Rev. C87 (2013) no.2, 024913
    e-Print: arXiv:1211.3048
  • The dipole model Monte Carlo generator Sartre 1,
    Tobias Toll, Thomas Ullrich (Brookhaven). 2013
    Comput.Phys.Commun. 185 (2014) 1835-1853
    e-Print: arXiv:1307.8059
  • Electron Ion Collider: The Next QCD Frontier : Understanding the glue that binds us all
    A. Accardi et al.. 2012. 100 pp.
    Eur.Phys.J. A52 (2016) no.9, 268
    e-Print: arXiv:1212.1701
  • Charm and bottom photoproduction at HERA with MC@NLO
    Tobias Toll (Brookhaven), Stefano Frixione (CERN & ITPP, Lausanne). 2011.
    Phys.Lett. B703 (2011) 452-461
    e-Print: arXiv:1106.1614

All publications: