Master Projects

Master Thesis Research Projects

The following Master thesis research projects are offered at Nikhef. If you are interested in one of these projects, please contact the coordinator listed with the project.

[MORE PROJECTS TO COME!]

The XENON Dark Matter Experiment: Data Analysis

The XENON collaboration is currently operating the XENON100 detector, currently the world’s most sensitive direct detection dark matter experiment. The detector operates at the Gran Sasso underground laboratory and consists of a so-called dual-phase xenon time-projection chamber filled with 160kg of ultra-pure xenon. The detector has been operational for a number of years and data is available for analysis. Our group has an opening for a motivated MSc student to do data-analysis on the detector. The work would consist of understanding the signals that come out of the detector and in particular focus on the so-called double scatter events. We are interested in developing methods in order to understand the response of the detector better. We are developing sophisticated statistical tools in order to do this. Due to the nature of the work, some familiarity with C++ is required.

Contact: Patrick Decowski

XAMS Dark Matter R&D Setup

The Amsterdam Dark Matter group has built an R&D xenon detector at Nikhef. The detector is a dual-phase xenon time-projection chamber and contains about 4kg of ultra-pure liquid xenon. We plan to use this detector for the development of new detection techniques (such as utilizing new photosensors) and to improve the understanding of the response of liquid xenon to various forms of radiation. The results could be directly used in the XENON experiment, the world’s most sensitive direct detection dark matter experiment at the Gran Sasso underground laboratory. We have several interesting projects for this facility. We are looking for someone who is interested in working in a laboratory on high-tech equipment, modifying the detector, taking data and analyzing the data him/herself. You will "own" this experiment.

Contact: Patrick Decowski

The Modulation experiment

There exist a few measurements that suggest an annual modulation in the activity of radioactive sources. With a few groups from the XENON collaboration we have developed four sets of table-top experiments to investigate this effect on a few well known radioactive sources. The experiments are under construction in Purdue University (USA), a mountain top in Switzerland, a beach in Rio de Janeiro and the last one at Nikhef in Amsterdam. We urgently need a master student to (1) do the final commissioning of the experiment, (2) collect the 1st big data set, and (3) analyse the first data. We are looking for an all-round physicist with interest in both lab-work and data-analysis. The student will directly collaborate with the other groups in this small collaboration (around 10 people), and the goal is to have the first publication ready by the end of the project.

Contact: Auke Colijn

Testing general relativity with gravitational waves

The Advanced LIGO and Advanced Virgo detectors are gearing up to make the first direct detections of gravitational waves over the next few years, with a first observing run scheduled for September 2015. Among the most promising sources are mergers of binary systems consisting of neutron stars and/or black holes. The ability to observe the emitted gravitational wave signals will, for the first time, give access to the genuinely strong-field dynamics of general relativity (GR), thereby putting the classical theory to the ultimate test. The Nikhef group has developed a data analysis method to look for generic deviations from GR using signals from merging binary neutron stars. We are now extending this framework to binary black holes, which have much richer dynamics and will allow for more penetrating tests of GR, but which also pose significant new challenges. The student will study the end-to-end response of the analysis pipeline to signals predicted by GR as well as a range of alternative theories of gravity, by adding simulated waveforms to real detector noise. Basic programming skills in C, Python, or related languages are a prerequisite.

Contact: Chris Van Den Broeck

Search for lepton flavor violation in Z decays with ATLAS Run 2 data

The lepton flavor violation is a mechanism which is forbidden by Standard Model and is not observed so far in experiment. However, it could explain a large amount of matter (and lack of antimatter) found in the Universe. Such mechanism could manifest itself in decays of Z bosons to tau and another lepton. Unlike other lepton flavor violating decays this channel is easier to record and identify. At the same time, the background from Z -> tau+tau, mu+mu, e+e decays can mimic signal and reduction of background is a challenge. All steps of this measurement (analysis of ATLAS data, tuning cuts on MC, understanding the background and trigger performance) are part of the master project. The programing of the code, the data analysis with ROOT and ATLAS software will be everyday tasks.

Contact: Olya Igonkina

Acoustic detection of ultra-high energy cosmic-ray neutrinos

Experiment The study of the cosmic neutrinos of energies above 1017 eV, the so-called ultra-high energy neutrinos, provides a unique view on the universe and may provide insight in the origin of the most violent sources, such as gamma ray bursts, supernovae or even dark matter. The energy deposition of cosmic neutrinos in water induce a thermo-acoustic signal, which can be detected using sensitive hydrophones. The expected neutrino flux is however extremely low and the signal that neutrinos induce is small. TNO is presently developing sensitive hydrophone technology that is based on fiber optics. Optical fibers form a natural way to create a distributed sensing system. Using this technology a large scale neutrino telescope can be built in the deep sea. TNO is aiming for a prototype hydrophone which will form the building block of a future telescope. Students project

Students have the possibility to participate to this project is the following ways: (i) Modeling of cosmic rays induced acoustic signal in a neutrino telescope. Keywords: Cosmic rays, Monte Carlo, signal processing, telescope optimization. (ii) Testing and optimization of fiber optical hydrophone for a large scale neutrino telescope. Keywords: Experimental, physics, system design.

The work will be (partly) executed in Delft.

Further information Info on ultra-high energy neutrinos can be found at: http://arxiv.org/abs/1102.3591 Info on acoustic detection of neutrinos can be found at: http://arxiv.org/abs/1311.7588

Contact: Ernst-Jan Buis

New physics from Higgs interactions with polarised W bosons

Higgs interactions with electroweak gauge bosons W+ and W- in the SM are a crucial, precisely defined part of the Standard Model. Measuring separately the Higgs coupling to longitudinally and transversely polarised bosons will determine, for the first time, if Higgs and gauge bosons are elementary, as predicted in the SM, or composite particles, indicating the presence of the BSM physics. The student will be involved in all steps of the analysis: Monte Carlo studies, the analysis of the ATLAS data and background rejection. The basic tools will include programming in C++ and Python and using ROOT.

Contact: Magdalena Slawinska