Neutrino Physics

Master/Bachelor Thesis DUNE

The near detector complex at the DUNE long-baseline neutrino oscillation experiment will use the PRISM approach: Some of the near detectors will be movable to different off-beam-axis angles to measure neutrino interaction event rates in different neutrino flux distributions. A linear combination of the event rate distributions at the different angles can then be used to predict the event rates at the far detector for different assumed values of oscillation parameters, with a reduced dependence on (and thus reduced systematic uncertainty caused by) neutrino-interaction models. The event rates measured at different angles can also be used to measure neutrino cross section as a function of neutrino energy, without having to rely on interaction models to reconstruct the energy on an event-by-event basis. This is a novel statistical approach that promises to allow measurements that simply were not possible to do in a model-independent way before. While it should work in principle, many question regarding the practical application of this methods remain and need to be investigated. A thesis in this topic would involve studying this method using simulated data, especially in regard to the question how it performs under realistic conditions.

Posted on

Master/Bachelor Thesis T2K

Neutrino Cross-section Measurements at the Near Detector of the T2K Experiment

Cross sections of neutrino interactions with matter are an important input into other neutrino experiments, like oscillation analyses. Unfortunately, our current models of neutrino-nuclear interactions are not able to describe the data in the 1 GeV neutrino energy region well. Cross-section measurements are thus a crucial tool to constrain systematic uncertainties for experiments working in these energy ranges (e.g. T2K, HyperK, DUNE). The AG Weber offers Bachelor and Master thesis topics investigating aspects of these measurements. This can include but is not limited to studies about different neutrino interaction models and how they compare to the data, sensitivity studies for future measurements, development of data selections at the T2K near detector for cross-section measurements, and investigation of statistical methods to extract the cross sections from the measured event rates.

Posted on

Master Thesis in Detector Development/Simulation

Neutrino physics is a captivating field dedicated to studying the characteristics of lightweight, electrically neutral particles with fascinating properties. Due to their weak interactions, detecting neutrinos is challenging, but their study provides valuable insights into astrophysical phenomena, such as stellar processes and the early universe. Fundamental research on neutrinos has yielded groundbreaking discoveries, including their mass and flavor-changing abilities. This field expands our understanding of the universe and finds practical applications in nuclear reactor monitoring and particle astrophysics.

This master thesis will be conducted within the Alfons Weber group in Mainz, as part of the LiquidO consortium. The group actively contributes to globally significant neutrino oscillation experiments like T2K and DUNE.

LiquidO (since 2016) is a novel detection technology for fundamental research and innovation, exploring the possibilities of light detection in opaque madia. Through active exploration of LiquidO's scientific potential, we uncover a multitude of new projects and experiments. The development of LiquidO entails extensive R&D and prototyping, fine-tuning its performance for ultra-sensitive particle detection, especially in the neutrino research field.

The thesis will specifically focus on the first LiquidO-based neutrino experiment, known as the CLOUD experiment. After the CHOOZ and Double Chooz experiments, CLOUD opens the third generation of experiments at Chooz power plant (France), the most powerful European site for reactor neutrino research.

One of the first goal of the thesis will be to concentrate on modeling and simulating the detector, which is a crucial phase in the development of the experiment. This work will contribute to shaping the future design of the detector within the collaboration.

Posted on

DUNE

Introduction

DUNE Experiment
The Deep Underground Neutrino Experiment (DUNE) at the Long Baseline Neutrino Facility (LBNF) is a next generation neutrino experiment planning to build a very large scale 40 kt LAr detector to provide unprecedented sensitivity to study neutrinos. The very large detector will be located at the Stanford Underground Research Facility (SURF) at a baseline of 1300 km from the Fermilab neutrino beam. DUNE proposes an immense scientific program and will answer many of the great questions of neutrino physics.

Origin of Matter

Could neutrinos be the reason that the universe is made of matter rather than antimatter? By exploring the phenomenon of neutrino oscillations, DUNE seeks to revolutionize our understanding of neutrinos and their role in the universe.

Unification of Forces

With the world’s largest cryogenic particle detector located deep underground, DUNE can search for signs of proton decay. This could reveal a relation between the stability of matter and the Grand Unification of forces, moving us closer to realizing Einstein’s dream.

Black Hole Formation

DUNE’s observation of thousands of neutrinos from a core-collapse supernova in the Milky Way would allow us to peer inside a newly-formed neutron star and potentially witness the birth of a black hole.
Mainz contributions to DUNE

The Mainz group is contributing to the near detectors of the DUNE complex, which are essential to understand the properties of the neutrino beam and how neutrinos interact with argon.

The process of a neutrino or anti-neutrino interacting with matter can be described by the neutrino exchanging a W- or Z-boson a neutron or proton within the argon nucleus. To understand this process it is not only important to understand the energy/momentum distribution of the argon nucleons, but also on how the particle produced inside the nucleus interact when traversing the nuclear medium of the argon nucleus.

This process will be studied by filling a TPC, a tracking chamber, with argon gas at 10 bar pressure. All, even very low energy charged particles, will leave a curved track in the TPC. Neutral particles like photons and neutrons will be measured with a calorimeter surrounding the TPC. This calorimeter will need to be able to measure the direction and energy of low and high energy photons as well as measuring the velocity of neutrons via their time of flight from the interaction vertex.

We are developing the design, detector technology and electronics for this calorimeter.

DUNE Near Detector

DUNE Near Detector (ND-GAr)

Please have a look here for Bachelor, Master and PhD theses in the ETAP group.

Posted on

Prof Alfons Weber

I hold a joint professorship at the University of Mainz and Fermilab and am a visiting professor at the University of Oxford. My main research interest is in neutrino physics, but I am also active in developing electronics and novel detectors.

Fun facts:

Research

I started my career in physics doing a diploma thesis in phenomenology, looking into novel way of detecting relict neutrinos from the big bang, or solar and accelerator neutrinos. After this more theoretical start at the RWTH-Aachen, I switched to experimental physics and did my Ph.D. and first post-doc at the L3 experiment at the LEP collider at CERN. I searched for new particles (but didn't find any) and made precision measurements of the W-boson mass.

I returned to neutrino, when I came to Oxford in 1999. I started to lead the Oxford MINOSgroup, who looks into the phenomenon of neutrino oscillations at Fermilab. We made a precision measurements using muon neutrinos from the NuMI beam line. More information can be found at the Fermilab MINOS page.

Later I joint the T2K experiment in Japan, which looks for electron neutrino appearance in a muon neutrino beam. We were awarded the Breakthrough Prize in Fundamental Physics for the measurement of neutrino oscillations and even found the first indication that neutrinos and anti-neutrinos don't oscillate in the same way. This process may eventually hold the key to understand why there is more matter than anti-matter in the universe. We need a new generation of experiments to really unlock the secret of the neutrino.

The DUNE Experiment is exact this. This very long baseline neutrino oscillation experiment is located in a neutrino beam that goes from Fermilab for 1300 km to the Sanford Underground Research Facility (SURF). The DUNE far detector will consist of 70,000 tons of liquid argon and will have an unprecedented sensitivity to measure neutrino oscillation. Its main aim is not only to study the matter anti-matter asymmetry, but to look for neutrino from supernova explosions or for the decay of the proton. I was the UK PI of the project and also leading a team to design the near detector, which is an essential component of the experiment to study the neutrino beam composition and the details of the neutrino interactions. I am the chair of the Institute Board of the International DUNE Collaboration.

I have also developed a novel detector for neutrino and neutron detection. These activities lead to the creation of the SoLid experiment, which searches for sterile neutrinos at the research reactor BR2 in Mol, Belgium.

Committees

I was serving on the STFC Science Board that provides advice to STFC Council and the executive on all aspects of STFC's science and technology programme.

I was on the Executive Committee of the MINOS and NOvA Experiments and was the chair of the institutional board and a member of the Executive Committee of the LAGUNA-LBNO design study. I am now the chair of DUNE's Institute board.

I am a member of the LHCC advising the CERN management on the LHC experiments concentrating on CMS and the WLCG. I also serve on the HyperK PAC advising the University of Tokio and KEK in Japan on the progress of the HyperK Experiment.

Master Thesis

Please get in contact with me, if you are interested in master thesis in my area of research. There are many options how you can make a difference in our research. One topic is listed below.

Posted on

IceCube researchers trace the origin of a neutrino from the depths of the cosmos

Elementary particles originate from three billion light-years distant galaxy / black hole as particle accelerator

original press release

Multimessenger astrophysics has been crowned with success: a research team has for the first time located a cosmic source of high-energy neutrinos. The trigger for the search was a single high-energy neutrino, which had been detected on 22 September 2017 in the ice of Antarctica by the neutrino telescope IceCube. Earth and space telescopes subsequently determined the origin of this elementary particle. It lies in a galaxy three billion light-years distant in the constellation Orion, in which a gigantic black hole naturally accelerates particles. Scientists from 16 astronomical observatories participated in the campaign worldwide. Among the researchers are also Prof. Dr. Sebastian Böser and Prof. Dr. Lutz Köpke from the Institute of Physics of Johannes Gutenberg University Mainz (JGU), which belongs since 1999 to the IceCube consortium. The results of this joint search were recently published in the journal Science.
(Image Martin Wolf, IceCube/NSF, 2017)