DESY Ukraine Winter School 2023

List of Research Projects

55. 3D printing accelerator structures

The student will work to design and 3D print dielectric structures for applications in accelerator science. With sufficient progress, the structures could also be tested with radiofrequency equipment.

28. A Neural Network parametrisation for Parton Distribution Functions in xFitter

The knowledge of the proton structure, embedded in the parton distribution functions (PDFs) is of fundamental importance to make predictions for proton-proton collisions at the Large Hadron Collider. PDFs are determined through fits to experimental data, and the functional form assumed plays an important role. Using too few PDF parameters, or a constrained parametrisation, can lead to...

40. Absolute gain calibration of 1 Mpix AGIPD detector at SPB/SFX instrument using EuXFEL X-ray beam

The European X-ray Free Electron Laser (EuXFEL) [1] is the world's most brilliant X-ray free-electron laser delivering up to 27.000 ultrashort (< 100 fs) spatially coherent X-ray pulses in the energy range between 0.25 and 20 keV, organized in 10 equidistant X-ray pulse trains per second. The facility went into its operation phase on July 1, 2017.

The 1 Megapixel AGIPD detector [2] is the...

54. Acousto-optic integrated microfluidic device for particle manipulation

Devices to handle small volumes in narrow streams is of great use in the serial x-ray crystallography experiments. We are developing a microfluidic device integrated with optical and acoustic components to facilitate the manipulation of flow as well as particles in the microchannel. We will offer the possibility for the student to work on the charecterisation of fluid flow for the fabricated...

48. AFM characterization of FEL irradiated samples

The aim of this project is to achieve better understanding of the interaction of intense XUV radiation with solid materials, in view of its prospective technological applications. The CFEL XM theory group is developing a modeling software which can simulate the interaction of intense XUV radiation with technologically relevant materials such as silicon and diamond. It is essential to check the...

21. Analysis of ultra-short XUV FEL pulses

In our group at FLASH (Free Electron Laser in Hamburg), we measure the temporal duration of the free-electron laser pulses by terahertz streaking. Photo-electrons are generated in the interaction of the XUV FEL pulse and noble gases like neon. If the ionization takes place in the presence of a THz field, the photo-electron spectrum is altered and contains information about the arrival time and...

7. ATLAS ITk Strips EC System Test Instrumentation

Context of the project

The ATLAS detector is one of the four LHC experiments and will be upgraded for the upcoming high luminosity runs. The inner detector is going to be entirely replaced by an all-silicon tracker (ITk). The System Test is the main testbench for detector modules. The goal is to have a realistic environment close the the real detector in terms of electrical noise,...

27. BELLE II: Analysis project

At the Belle II experiment, B meson decays can be studied with highest precision and in particular so called semi-leptonic decays where the B meson decays to a
hadron, a lepton and a neutrino. In this context, when the hadron contains an up quark (B → Xu l nu), important Standard Model parameters can be measured.
However, this process is overwhelmed by the much more likely decay to a hadron...

25. BELLE II: analysis project: tau lifetime or detector alignment related project

BELLE II: analysis project: tau lifetime or detector alignment related project

17. Capacitance Studies of a Monolithic Active Pixel Sensor in a 65 nm CMOS Imaging Technology

Monolithic CMOS sensors have found their way into High Energy Physics thanks to multiple advantages in particle detection. Their main characteristic is the integration of the sensor and the readout electronics in a single chip, which provides a reduction in production effort, costs and material. As part of the next generation of silicon pixel sensors, that are usually employed as tracker and...

46. Characterisation of CMOS Cameras for the LAST Optical Telescope

The LAST telescope is a project to create an extremely wide field of view optical telescope, capable of searching for a wide range of transient source including tidal disruption events, compact binary mergers and many other violent astrophysical phenomena. LAST will be constructed from forty eight 28 cm telescopes with high performance CMOS cameras, working together to cover a sky area of...

29. Characterization of digital cameras based on photon transfer measurements

Area scan sensors (CCD or CMOS cameras) are widely used for beam profile
measurements in particle beam diagnostics. They provide the full two-dimensional information about the beam distribution, allowing in principle to investigate shot-to-shot profile fluctuations at moderate repetition rates. In order to study the performance and to characterize these cameras, photon transfer is a widely...

16. CMS Phase-2 Tracker Integration

The student will participate in various activities related to the integration of the CMS Phase-2 Tracker Endcap.
The integration of detector modules onto the supporting mechanical structure brings various chal- lenges that have to be addressed. The thermal coupling of the PS detector modules using a thermal interface material has to be established. Candidate materials are being studied. The...

8. CMS Tracker Alignment, DESY CMS group

The DESY CMS tracker alignment group is a team responsible for development and operation of the software tools performing the alignment of the CMS silicon tracker detector. In the context of this project, the student will join the DESY tracker alignment group, learn to work with the data-driven methods used to derive the alignment parameters & their validation, and participate in the ongoing...

14. CMS Tracker Module Testing

We offer a project related to the CMS Outer Tracker Upgrade. At DESY, we will produce 1200 PS modules, whose components have to be tested prior to assembly. Moreover, assembly procedure are currently being verified as well as the testing procedures for final modules.
The student will involved in these activities working in the Detector Assembly Facility.

38. Coherent X-ray Diffraction Imaging on mesocrystals and catalytic nanoparticles

Coherent X-ray Diffraction Imaging is a comparably new technique that allows to reconstruct the real space image of the particle illuminated by coherent X-rays. In this project we propose to perform reconstruction of previously measured data from mesocrystals and catalytic nanoparticles.
These data were obtained at PETRA III synchrotron source at DESY or at ESRF synchrotron source in Grenoble.

18. Completion and documentation of a public Open Data analysis example combining CMS and ATLAS Higgs->four lepton signals in the the context of PUNCH4NFDI

Open Data analysis examples in High energy physics are so far available
in simplified approaches for educational purposes, or at research level
in dedicated technically rather demanding environments.
Recently an example has been set up successfully within the PUNCH4NFDI
project, compiling a significant Higgs->4L signal peak reminiscent of the original discovery, which combines public...

30. Constraints on the proton structure from CMS measurements of Standard Model processes

The knowledge of the proton structure, embedded in the parton distribution functions (PDFs) is of fundamental importance to make predictions for proton-proton collisions at the Large Hadron Collider. PDFs cannot be calculated through perturbative methods, but are determined through fits to a variety of experimental data.

Aim of this project will be to investigate the sensitivity to PDFs of...

52. Data and Metadata Processing Workflow for Multi Dimensional Photoemission Spectroscopy

Rapidly increasing development of accelerator-based light sources like synchrotron radiation or free-electron-laser (FEL) facilities and detectors have brought photoemission spectroscopy to a new regime in data acquisition. Data streams resolving each individual photoelectron event enable correlation of each detected electron to the full state of the experimental apparatus, allowing drift and...

24. Deep Learning-Based Time-of-Flight Reconstruction for Future Higgs Factories

Experiments at future e+e- collider Higgs factories present the opportunity to perform measurements of the Higgs boson and electroweak observables with unprecedented levels of precision. Utilizing such machines to their full physics potential places stringent requirements on the performance of the detector. As a high level reconstruction task, highly performant particle identification is...

53. Detailed investigation of multidimensional serial crystallography

We are developing methods for serial crystallography at synchrotrons and XFELs to investigate structure and dynamics of biological macromolecules. Here we focus on temperature and pH-control to combine with mix-and-diffuse triggering of biochemical reactions for multidimensional crystallography (temperature-, pH- and time-resolved). You would be working with us for detailed investigations of...

39. Di-top mass reconstruction using advanced Machine Learning methods

In the Standard Model fermions obtain their masses ($m_f$) via the spontaneous symmetry breaking mechanism. To describe the coupling between Higgs and fermion fields a Yukawa coupling is introduced. The masses are then proportional to the vacuum expectation value of the Higgs field and the Yukawa coupling ($g_f = \sqrt{2} m_f / \nu, \nu=246.22$ GeV). Since the top quark is the heaviest known...

20. Exploratory study for the combined analysis of particle physics and astroparticle physics data in the context of PUNCH4NFDI

Recently combined analysis of data from different High Energy Physics
experiments in a common basic research level data format has started
to be achieved in the context of the PUNCH4NFDI initiative.
In this exploratory study the concept will be extended to include
data from an Astroparticle Physics experiment. In particular, public
cosmic air shower data from the Karlsruhe air shower...

47. Facilitating X-ray beamline alignment with machine learning

Large scale research facilities for top-level science, such as synchrotrons, free-electron lasers and optical lasers like FLASH/DESY, European XFEL, CELIA etc., operate complex beamlines, where a set of optical elements is used to guide and shape photon pulses, and to perform advanced fundamental and applied science experiments. Such experiments place high demands on the quality of the...

51. FEL and HHG-based time-of-flight momentum microscopy: 3 time-resolved photoemission modalities in 1 experiment

Time-resolved photoemission spectroscopy with ultrashort pump and probe photon pulses is an emerging technique with wide application potential. The ultimate combination of valence-band and core-level spectroscopy with photoelectron diffraction in a single experiment for electronic, chemical, and structural dynamics analysis specifically requires tunable monochromatic VUV or soft X-ray pulses...

9. GPUs 4 top quarks

Top quarks are important particles that, due to their large mass, provide a direct probe to the Higgs sector and possible extensions of the standard model of particle physics. At the LHC, the standard model predicts top quarks to be produced in pairs, alone, or in groups of four, of which the CMS experiment recently observed evidence. The production of three top quarks is another order of...

2. IceCube Upgrade optical module characterisation

Summer Blot (Z_ICE (IceCube+NG))

In 2025/26 hundreds of new optical modules, which use photomultiplier tubes, will be deployed in the deep ice at the South Pole to detect Cherenkov radiation produced by high energy neutrinos. At DESY we are building and testing these modules to ensure they meet the desired performance requirements. This project will involve characterising the response of modules in realistic (sub-zero)...

56. Impact of missing transverse momentum resolution on sensitivity to Dark Matter in top quark events

The main signature in searches for Dark Matter at the Large Hadron Collider is the presence of missing transverse energy in the final state, given the invisible nature of these particles and thus the impossibility of identifying them when traversing the detectors. The success of finding the dark particles relies then on a good and precise measurement of the missing momentum along the...

19. Implementation, test and documentation of a public analysis example combining Quarkonium data from the CMS and ZEUS detectors in the context of PUNCH4NFDI

Quarkonium, and in particular J/psi final states have been measured in both the ZEUS (ep) and CMS (pp) experiments. These measurements mainly focused on dimuon final states. A common research level analysis format for ZEUS and CMS data has recently been extended to contain electrons. The measurement of J/psis in both muon and electron final states will be exploited in this project.
This...

57. Improved sensitivity to BSM Higgs bosons from final states with unreconstructed particles and a modified approach to kinematic event reconstruction

Searches for heavy Higgs bosons decaying into pairs of top quarks is a promising avenue to discover new physics at the LHC. Due to the so-called peak-dip structure from interference effects with Standard Model ttbar production, current searches rely on fully reconstructed final states, which require the presence of at least 2 jets and 2 leptons. In this work, the inclusion of final states with...

36. Liquid flat sheet jets characterization

The development of sub-micrometer-thickness flat sheet jets has enabled several novel achievements in science. The micrometer thickness, high stability, and optical flatness of the flat sheets are key characteristics required for the successful exploitation of these systems, especially for the spectroscopic study of aqueous samples [1,2].
Recently, several methods of achieving flat jets of...

3. Long-lived Particles at the FCC-ee

Many physics problems such as the nature of dark matter predict particles with long lifetimes as an important possibility in the search for new phenomena. When produced at colliders, these long-lived particles (LLPs) have a distinct experimental signature: they can decay far from the collision point, or even completely pass through a detector before decaying. Since most of the trigger and...

4. Model-based analysis of nanoscale interface evolution during spray coating

In modern thin film technology, spray coating plays a crucial role in fabricating flexible electronics and photovoltaics. The complex interface and multilayer structure are deduced by surface-sensitive scattering methods [1]. Spray coating was applied to create functional layers, from novel latex colloids to complex biomaterials templates [2,3]. There is a strong need to go beyond a...

33. Modelling the evolution of X-ray-irradiated materials on femtosecond to nanosecond timescales

Modern X-ray free-electron lasers (XFELs) produce femtosecond X-ray pulses sufficiently intense to modify material properties or damage the target. On the femtosecond timescales, energetic photoelectrons (created upon the X-ray absorption) and Auger electrons (emitted after relaxation of core-hole states) trigger secondary electron cascades, which contribute to the increasing transient free...

44. Multi-wavelength study of cosmic rays and turbulence

A new chapter of cosmic ray (CR) propagation research has begun when studies of particle transport and interstellar turbulence can confront each other.
In this project, multi-wavelength observations from radio to gamma ray shall be utilized to study magnetic turbulence and the propagation of CRs based on the theoretical understandings.

45. Muon Collider Sensitivity to BSM Models with Extra Gauge Bosons and Heavy Neutral Leptons

The projects is 50% physics and 50% software roughly. The goal is to study the sensitivity of future high-energy muon colliders on models beyond the Standard models that contain both additional gauge bosons (Z') and heavy neutral leptons, i.e. heavy neutrinos. Heavy neutrinos shall be studied in prompt production and via decays of the Z'. In addition, the properties of the additional gauge...

34. Next generation of photovoltaics development

Inorganic catalyst composites - organic polymers can be used as light harveting devices with a similar efficiency as silicon. When coupled to a water splitting unit like minerals / perovskites we can build novel type of energy converter and energy storage materials.
In this proposal we will develop such novel classes of materials and study them with advanced optical spectroscopy and advanced...

35. Novel generation of photovoltaics and energy converter

Organic polymers can be used as light harveting devices with a similar efficiency as silicon. When coupled to a water splitting unit like minerals / perovskites we can build novel type of energy converter and energy storage materials.
In this proposal we will advance our data analysis capabilties in X-ray scattering / diffraction.

59. Plasma wakefield acceleration

The most impressive experimental results (see [1, 2]) until now in electron accelerating by a wakefield, excited in a plasma, have been achieved using capillary-generated plasma. Plasma-wakefield acceleration provides high accelerating gradients (see [1, 3, 4]), promises compact accelerators of high-brightness and high-energy electron beams. Applications of plasma-wakefield accelerators, in...

37. Processing serial crystallography data measured at FELs and synchrotrons

Our group (group leader H.N.Chapman) is one of the inventors of Serial Crystallography (SX) – the method when many protein crystals are measured in random orientations to get the full 3D structure of the protein. This technique was developed for Free Electron Lasers (FELs) but now it is also becoming a standard technique used at modern synchrotrons. Having a lot of experience and expertise in...

31. Pulsars at very-high energies: developing and testing pulsar analysis

The discovery of a new radiation component at TeV energies in the Vela pulsar, beating at the same frequency that the rotational period of the pulsar, has opened the door for new, exciting interpretations of acceleration of particles in extreme environments. The H.E.S.S. archival dataset with more than 15 years of observations offers a fantastic opportunity to search for more of these objects....

5. Quantum dynamics with normalizing flows

In this project, we are investigating the viability of applying machine learning to quantum mechanical simulations of molecular dynamics, such as molecular vibrations and rotations in external fields and electron ionization by strong laser fields. The underlying concept of this method is to find solutions to the Schrödinger equation using recurrent neural networks combined with normalizing...

32. Sample preparation and characterization for time-resolved serial crystallography with MurA

The basic concept of serial femtosecond crystallography (SFX), diffraction-before-destruction, made it possible to collect radiation-free data with nano- and micro-crystals at room temperature. As the crystals are usually only shot once by a single short X-ray pulse and destroyed, sample preparation requires production of large numbers of crystals with homogeneous size distribution and high...

41. Semantic Segmentation Of Pileup Particle Identification In The ATLAS Detector

Simulating pileup at the Large Hadron Collider (LHC) involves the simulation of multiple proton interactions via soft QCD Monte Carlo models that are then overlaid onto a single primary interaction (or hard scatter event). This poses a significant challenge moving into the high luminosity era due to the increased average number of interactions per bunch crossing, and the growing complexity of...

83. Studies of the proton structure with the xFitter framework

Parton distribution functions (PDFs) are essential to make theoretical predictions for experimental measurements of collider experiments with initial state hadrons. The xFitter project is an open source QCD fit framework ready to extract PDFs and assess the impact of new data.
The student will study constraints of recent LHC data on the proton PDFs and SM parameters by implementing the data...

43. study of compressible turbulence

Interstellar turbulence is magnetised and compressible. Compressible turbulence plays a key role in both cosmic ray transport and star formation. In this project, the properties of compressible turbulence will be the focus, in particular, their cascade and statistical properties.

58. Study of the performance for identification of charged kaons in the Belle II experiment

Collisions produced in the interaction region of the Belle II experiment produce as final states charged and neutral particles that travel across the different subdetectors. A proper charged particle identification system is a critical requirement for the success of the physics program at Belle II. In particular, the tau lepton physics program require the identification of charged kaons from...

12. Tangerine Project: Transient Simulation Studies in a 65 nm CMOS Imaging Process

The implementation of new detector technologies is mandatory to continue the rapid evolution of High Energy Physics Experiments. The goal of the Tangerine project is to develop the next generation of monolithic silicon pixel detectors using a 65 nm CMOS imaging process, which
offers a higher logic density and overall lower power consumption compared to previously used processes.

The...

11. TANGERINE – Test beam characterization of Monolithic Active Pixel Sensors

Tracking detectors are key parts of the instrumentation in high energy physics experiments, and their majority is making use of silicon pixel sensors to detect charged particles. A new generation of Monolithic Active Pixel Sensors (MAPS), produced in a 65 nm CMOS imaging process, promises higher densities of on-chip circuits and hence smaller pixel sizes or more sophisticated circuitry. MAPS...

42. Tau reconstruction exploiting ML techniques

Hadronically decaying tau leptons are powerful probes for electroweak physics. The precise measurement of their properties is key to measuring the properties of vector and scalar bosons, as well as the structure of the Yukawa coupling. This project focuses on exploiting machine learning techniques to reconstruct tau decays in collider experiments, as well as achieve an optimal reconstruction...

22. Test of a new Beam Position Monitor readout system for PETRA IV

For synchrotron light sources undergoing upgrades to 4th generation facilities, the importance of beam stability has grown substantially, i.e. tighter stability requirements over greater bandwidths over various timescales. From the electron beam diagnostic's point of view, Beam Position Monitors (BPMs) form the monitor system which provides the required data in order to keep the beam orbit...

10. The effect of the atmospheric composition on CTA performance

Studying the Universe at the highest energies with photons above 10s of GeV requires a very special detector, the atmosphere. When very-high-energy (> 10 GeV) gamma rays hit the atmosphere, they produce an extended air shower of electromagnetic particles, which in turn induce Cherenkov radiation. The distribution of Cherenkov light induced and its probability of reaching the detectors on the...

60. Time-resolved single particle imaging study on nano structures

This project introduces the concepts of x-ray coherent diffraction imaging and the application of these concepts to single particle imaging experiments at free electron laser sources. The project is hosted by scientists of the SPB/SFX (Single Particle, clusters & Biomolecules and Serial Femtosecond Crystallography) scientific instrument at the European XFEL.

The computational tools used to...

49. Ultra-High-Energy Cosmic Rays propagation in extragalactic space from a single source

Investigating the ultra-high-energy cosmic rays (UHECRs) is crucial to understand the most energetic phenomena in the Universe. The main focus of this project is to study the propagation of cosmic rays at energy about $10^{18}$ eV. You will learn to calculate cosmic ray flux at Earth from a single source for different parameters . The results will be compare to the measurement of energy...

6. Upgrade of CMS LHC beam pickup logic

The beam pickup signals are processed at the CMS experiment at CERN by a programmable logic board programmed in VHDL. Coincidences between the signals from clockwise and counterclockwise beams are formed and provided to the CMS trigger logic. This project will reimplement the logic on a modern Cyclone V based FPGA and verify its operation by simulating LHC bunch patterns. Additional monitoring...

15. UV laser beamline diagnostics @REGAE

For the new UV GUN laser beamline @REGAE there is a huge need to get a highly precise virtual cathode diagnostic. The design is done and the diagnostic has to be set up in cooperation with experienced members of the group. If the setup is ready the optimization of the laser beam alignment and characterization of the laser beam is the main topic. Some knowledge about data analysis would be...

23. V0-Finding at a Future Higgs Factory

The next big particle collider project is foreseen to be an e+e- Higgs factory. Various detector concepts with advanced detector technologies have been proposed for such colliders, aiming to probe the Standard Model to unprecedented precision. In order to optimise the physics performance of these detectors, sophisticated reconstruction algorithms are being developed and benchmarked on detailed...

50. Variational Quantum Algorithms

Variational Quantum Algorithms are a class of hybrid quantum-classical algorithms. This technique makes use of a parametric quantum circuit that is executed on quantum device as an ansatz whose parameters are optimized using a classical computer based on the measurement outcome of the quantum device. Running the feedback loop between the classical computer and the quantum coprocessor until...

61. Wavefront analysis using python

At-wavelength wavefront metrology techniques are used at FLASH to characterize the beam aberrations. Our group has a long expertise trajectory using Hartmann Wavefront Sensors in the Extreme Ultraviolet regime. These methods, in combination with focusing optics, are a fast approach to describe the focus in situ. However, for strongly focusing optics, or telescope-kind optics a specific...