Summer Student Projects Submission 2024

Contribution List

59. Accelerator operation and machine development studies at PETRA III

This summer student project will provide a deep insight and contribution to the daily operation of one of DESY’s core facilities – the world’s biggest and one of the most brilliant storage ring light source PETRA III.

In preparation for the planned facility upgrade to PETRA IV, machine development studies in PETRA III already now aim for the development of hardware and software components...

27. Advancing a game-changer for ultrafast lasers: Multi-pass cells

N/A

25. Algorithms for serial crystallography

The student will join the new Scientific Computing group in Photon Science, and implement new algorithms for serial crystallography experiments as performed at PETRA III and the European XFEL.

92. Analysis of the LHC data using xFitter

Perform studies of parton distribution functions and higher order QCD corrections using xFitter QCD analysis framework

50. Applications of Transfer Matrix Based Quantum Algorithms

Quantum simulation utilizes the relatively easily controllable quantum systems to simulate and understand the more complicated quantum processes. For finite size systems, many quantum algorithms have been put forward to tackle the real time evolution and imaginary time evolution. However, for systems in the thermodynamic limit, the practical realization of the simulation schemes are still...

17. Applying ptychography to phase-sensitive laser beam characterization

To predict the propagation of a laser beam through an optical assembly, it is crucial to determine its spatial electric field. Standard beam profilers only measure amplitude, but a wavefront cannot be retrieved. Also, the standardized M2 method does not deliver the full phase information of a laser beam. The goal of the student project is to test a simple but very powerful method to overcome...

48. ASAP::O development

The ASAP::O high performance distributed streaming platform was designed to be able to keep up with huge data volumes and frame rates of next generation high-speed detectors. ASAP::O allows the scientist to focus on science, while taking care of storage and network and the delivery of the experiment data at the required destination. It is provided with an easy to use API in Python or...

70. ATLAS ITk strip detector - developments on the end-cap system test

The ATLAS detector is one of the four LHC experiments and will be upgraded for the upcoming high luminosity runs. For that, a new all-silicon tracking detector, the Inner Tracker (ITk), is being built right now. At DESY, the so-called system test for the end-cap system is being developed and serves as the main testbench for the whole detector concept.

Within the summer student project, the...

88. Baryogenesis and black holes from the chiral gravitational anomaly

We propose studying the inflationary model presented in [2001.08220], which is able to produce a significant population of primordial black holes, together with a CP-violating coupling between the inflaton and the Riemann tensor, as in [hep-th/0403069]. This would potentially allow us to explain both dark matter and baryogenesis from a minimal setup involving only the addition of single-field...

55. Belle II data analysis

Belle II is the detector operated at the Super KEKB accelerator in Japan since 2019. The DESY group is active in B and tau physics analyses and in the monitoring of the performance of the Pixel detector in terms of efficiency and resolution at the highest luminosities. The summer project would be in one of these areas depending on data availability and student's preference. Data are stored in...

28. Bending light in air and beyond

N/A

64. Bright X-rays from Plasma Accelerators: A Free Diagnostic Tool?

Plasma accelerators [1-4] hold great promise to dramatically reduce the size and cost of future electron accelerators, providing a route to increased access to accelerator facilities and reduced environmental impact. When two short electron bunches, separated in time by a few hundred femtoseconds, are focussed in to a plasma the space-charge force of the leading bunch expels plasma electrons...

33. Characterization and optimization of femtosecond electron bunches in a novel pin-cathode RF Gun

A femtosecond time resolved electron diffraction setup is being commissioned at FS-CFEL-2. Based on a novel compact pin cathode RF gun, 150 keV electron bunches with a bunch charge of 100 fC with self-compressing sub- 100 fs pulse duration are achievable. Optimization of UV trigger pulse parameters are required to obtain the best possible bunch parameters on target. This project entails...

18. Characterization of a spatial light modulator for shaping the optical phase of ultra-short laser pulses

DESY's VUV Free Electron Laser (FEL), FLASH, is currently undergoing a major upgrade to become the world's first externally seeded FEL operating at high repetition rates. The external seed laser is a crucial component of this extensive facility project, which is presently under construction. The proposed SLM characterization project forms a part of the ongoing development of the seed laser and...

20. Characterization of the first High-Z AGIPD detector prototypes

The AGIPD hybrid pixel detector was developed specifically for the unique beam structure of EuXFEL, and has been in operation with silicon sensors since 2017, enabling several successful user experiments. Now, in order to enable experiments with higher X-ray energies at EuXFEL, DESY has started the development of AGIPD detector prototypes using high atomic number (High-Z) sensors of different...

90. Characterization of the instrumental function for wide angle scattering at the P21.2 beamline

The advent of efficient area detectors has accelerated the data acquisition of high-energy wide angle X-ray scattering (WAXS) by several orders of magnitude. By now, detectors with tens of megapixels are available which also enable high-resolution analysis in reciprocal space. To design optimized experiments, the angular resolution function of the instrument (i.e. the beamline configuration...

19. Commissioning and testing our new TEMPUS system (Timepix-4 based X-ray imager)

N/A

15. Computational Coherent X-ray Imaging via Deep Learning

The student will help to build a physics-informed model of a diffraction experiment and then use deep learning methods to solve the inverse problem to recover an image. They will apply it to experimental data of novel functional materials at nanometer resolution.

98. Construction and characterization of Yb:YVO4 Laser System

Since the creation of the first operational laser in 1960, lasers, Light Amplification by Stimulated Emission of Radiation, have found applications in various fields such as research, communications, medical procedures, and materials processing. The Ultrafast Optics and X-rays Group at CFEL is one of the most advanced groups in the world, developing high energy and high-power lasers. Nowadays,...

56. Critical evaluation of discriminator networks for assessing simulation.

The FTX Software (SFT) group develops calorimeter simulation for future high granularity detectors. In particular, this group is interested in fast and accurate reproduction of full scale calorimeter simulations using Machine Learning (ML) techniques. When such a tool is put into production, the output is reconstructed by an armoury of equally complex algorithms, both classical and ML based....

62. Crosstalk Characterization of a Digital SiPM in 150 nm CMOS Imaging Technology

Silicon Photomultipliers (SiPMs) are silicon detectors widely used for light detection in contexts where features such as high detection efficiency and temporal performance in ps regime are required. Analog SiPMs are characterized by an array of single cells (SPADs) in parallel, producing signals proportional to the number of photons incident in the active area.
In digital versions of SiPMs,...

81. Data analysis in relation to pump-probe data.

Data analysis will be performed in relation to pump-probe data from the MID instrument.

47. dCache authentication plugin

The dCache project provides open-source software deployed worldwide to meet more demanding scientific storage requirements. Its multifaceted approach offers an integrated way of supporting different use cases with the same storage, including high-throughput data ingest, data sharing over wide area networks, efficient access from HPC clusters, and long-term data persistence on tertiary...

40. DESY CMS - Calibration of the new CMS luminosity detector BCM1F

The BCM1F detector of the CMS experiment consists of 48 silicon pad sensors situated close to the beam pipe on both sides of the interaction point. The detector provides an online, quasi-real-time
measurement of the instantaneous luminosity the CMS and the LHC control rooms. For the Run-3 data taking, BCM1F was completely refurbished.
The topic of the Summer Student project is data analysis...

43. DESY CMS - Estimation of improvements in the model-independent FL structure function measurement with HERA and simulated EIC data

At HERA, the FL structure function has been estimated in a model-independent way using inclusive cross sections measured at three different
center-of-mass energies. The future Electron-Ion Collider (EIC) will
routinely operate with five different center-of-mass energies. In this
project, we aim to estimate improvements in the FL measurement by utilizing simulated EIC data, both with and...

46. DESY CMS - Impact of the resolution of missing transverse energy in searches for Dark Matter with dileptonic final states:

Impact of the resolution of missing transverse energy in searches for Dark Matter with dileptonic final states: Dark Matter is a great mystery in science today. 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...

44. DESY CMS - Making the top quark open in the CMS open data

The top quark is one of the building blocks of the Standard Model, and the heaviest known particle. Up to now, top quarks have been only visible at the Tevatrong Collider at Fermilab and at the LHC. Top quarks are important to many studies of the strong force and the production probabilities are sensitive to the ratio of gluons and quarks in the protons.
The goal of this summer student...

41. DESY CMS - nanoAOD Pepper software performance tests

Testing event selection and branch selection and partial event reading.

38. DESY CMS - Physics project with CMS and other Open Data

Physics project to be prepared for use at the 2024 CMS Open Data
workshop, including the latest data release and/or as a PUNCH4NFDI
use case example. Since these will be for real use, details will
be fixed when all the boundary conditions are finally known.
(could be split into two separate projects if space is left)

45. DESY CMS - Reconstructing dark matter in events with top quarks using neural networks

Some beyond the standard model (SM) scenarios predict that dark
matter (DM) could be produced in association with top quarks at the LHC. The most easily identifiable case in which this occurs are dileptonic top quark pair + DM events, however reconstructing the kinematics in these events is challenging as the DM, in addition to two neutrinos from the top quark decays, are not observed. In...

42. DESY CMS - Search for Hexaquarks

Physics Data Analysis project searching for new physics
in data recorded with CMS at the LHC

75. DESY CMS - Study of the Higgs boson's parity properties using the columnar analysis framework

Stepan Zakharov (DESY (Deutsches Elektronen Synchrotron))

The student will be involved in activities related to the measurement of the Higgs boson CP properties. The set of topics to work on includes improving the Data/MC agreement of the Run3 data collected by the CMS detector. In addition, the student will gain some experience in developing
the analysis tools to measure spin-sensitive variables in the decays of the Higgs boson into a pair of tau...

39. DESY CMS - Tracker Alignment: Studies with Phase 2 detector geometry

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...

37. DESY CMS Phase-2 Outer Tracker Upgrade - Detector Qualification

The CMS group at DESY is heavily involved in the construction of the Phase-2
upgrade for the Outer Tracker and is responsible for the integration of one
of the endcaps. The endcap comprises five double disks, each built from four
half disks (Dee). As the integration work is scheduled to start at the end
of 2024, over the course of the year we will receive pre-production parts,
both for...

54. Detector design at an asymmetric linear Higgs factory

A future Higgs factory using a mixture of plasma wake-field acceleration for electrons and radio-frequency acceleration for positrons has recently been proposed. With this Hybrid Asymmetric Linear Higgs Factory (HALHF), a much shorter and therefore cheaper collider could be built.
Such facility would feature energy-asymmetric beams, leading to forward-boosted collisions. We started looking at...

72. Detector study of a Cherenkov detector for the strong-field QED experiment E320 at SLAC

A novel group of experiments will study strong-field quantum electrodynamics in the interactions of a beam of electrons with a high-intensity laser. Two such experiments are LUXE at DESY (Germany) and E320 at SLAC (USA). The spectrum of the electrons from this interaction needs to be characterized. The measurement is challenging since roughly 1010 electrons with energies up to 10 GeV arrive at...

94. Determination of nonperturbative contributions from comparing high-precision predictions and measurements of the Z-boson pT-spectrum at the LHC

Investigate nonperturbative contributions and their impact on the Z-boson pT-spectrum at small pT, determine the relevant parameters by fitting available precision predictions and measurements of the Z-boson pT-spectrum, and investigate their impact on the precision determination of the strong coupling and PDFs from the Z pT spectrum.
- about 40% physics, 30% numerical analysis and 30% coding...

35. Disappearing tracks in ATLAS for Run 3 searches

Various models of physics beyond the Standard Model predict particles with significant lifetimes, which can produce unique signatures in collider experiments. In the ATLAS experiment, charged particles that live just long enough to pass the innermost layers of the tracking detector can be reconstructed as so-called disappearing tracks. These particles appear for example in some supersymmetric...

32. Dispersion characterization of apodized chirped Bragg gratings and mode-locked laser cavities using white light interferometry setup

Apodized Chirped Bragg Gratings (ACGs) optical component is a reflecting Bragg grating with a period gradually varying along the direction of beam propagation. We designed and fabricated apodized chirped Bragg gratings in a silicon nitride-on-insulator platform for dispersion compensation in on-chip mode-locked lasers (MLLs) operating in the short-wave infrared wavelength band. To measure the...

95. Estimation of higher-order corrections and theory uncertainties in the Higgs and Z-boson pT-spectrum at the LHC

Using effective-field-theory methods (factorization/resummation) to predict and analyze the 4-loop structure of the pT spectrum at small pT.
Use this to get a precise estimate of higher-order theory uncertainties and their correlations.
- about 75% physics (mostly analytic/symbolic) and 25% coding (C++)

74. Evaluating the Sensitivity of Future Higgs Factories to Exotic Scalars

An electron-positron collider for precision studies of the Higgs boson has been identified as the highest-priority next collider for particle physics. Besides studying the 125-GeV Higgs boson in much greater detail than the LHC will be able to do, such ``Higgs Factories'' are also ideally suited to search for additional Higgs bosons or, more generally, scalar particles produced in association...

11. Explore nonlinear materials for novel x-ray wave mixing

Nonlinear optics was kick-started by the invention of the laser and has since revolutionized broad areas of science and technology. Today, we witness the same development in the x-ray regime, where nonlinear processes are made accessible by free-electron lasers (FEL). In addition to novel sources, however, new materials are likewise needed to extract the most from nonlinear effects.
Take...

13. Exploring Biomolecular Structures: Utilizing Electrospray Ionization and Ion Mobility Spectrometry for Characterization

Biomolecules such as proteins and peptides are chains of amino acids that are linked by peptide bonds and are normally folded in their natural environment. The three-dimensional structure depends on the amino acid sequence and is responsible for the biological function of the proteins. To extract the intrinsic physical properties of those molecules without any interference with the environment...

73. Exploring the electron + track signature to measure tau g-2

Measuring the anomalous magnetic moment (‘g-2’) of the tau is a fundamental test of the Standard Model and discrepancies between measurement and theoretical prediction could reveal new phenomena. However, tau g-2 is poorly constrained due to the short lifetime of the tau lepton.

The ATLAS experiment recently made one of the first new measurements of tau g-2 in nearly two decades [1]. The...

68. Fine-tuning Monolithic Active Pixel Sensors Simulations

Future lepton and electron-ion collider concepts rely heavily on silicon sensors as primary tracking devices. Therefore, investigating silicon sensor ideas that provide cost-effectiveness and good performance is essential. One of the aspects of the DESY Tangerine Project involves assessing monolithic active pixel sensors (MAPS), which are developed using 65 nm CMOS imaging technology....

36. Flavour tagging performance studies in the ATLAS experiment

The identification of jets containing b-hadrons (b-jets) is an important ingredient in the physics program of the ATLAS experiment. The student will evaluate the performance of existing b-tagging algorithms and FTAG tools used in ATLAS and propose and implement optimisation to improve the b-jet efficiency. The student will also compare the performance of the flavour tagging algorithms in...

4. Flexible electronics and photovoltaics: Retrieving real-space structures from scattering pattern

In modern flexible electronics and photovoltaics, spray coating plays a crucial role in fabricating flexible electronics and photovoltaics. The complex interface and multilayer structures are extracted from surface-sensitive scattering methods, using grazing incidence X-ray scattering and X-ray reflectivity [1,2,3]. Here, we apply spray coating to create functional layers, from novel latex...

89. Formation and implications of ultra-light dark matter solar halos

An ultra-light particle, with mass smaller than about 1 eV, is an excellent dark matter candidate. Along the lines of https://arxiv.org/abs/2306.12477 and https://arxiv.org/abs/2207.04057, the project will study the formation, via gravitational interactions, of halos of ultra-light dark matter around compact objects (for instance the Sun or a supermassive black hole). The work will be mostly...

21. Generating femtosecond UV pulses from an infrared laser

In the attosecond science group at CFEL (https://atto.cfel.de), we generate ultrashort laser pulses with attosecond (1 as = 10−18 s) or few-femtosecond (1 fs = 10−15 s) duration. These pulses are used to trigger ultrafast dynamics in a variety of systems, from bio-relevant molecules to clusters and nanosystems, and to follow in real-time how the atoms and electrons move and interact. With our...

2. Harnessing neural networks for simulations of rotational-vibrational dynamics of floppy molecules

This project builds upon a novel method recently developed in our group, which employs normalising flows (invertible neural networks) for solving the Schrödinger equation. This approach has demonstrated significant advancements in simulating the quantum vibrational dynamics of molecules, outperforming traditional variational methods. The current project's objective is to expand this...

12. Implement topography for x-ray crystal optics in the lab

The development of novel and highly brilliant x-ray sources, like 3rd generation synchrotrons and free-electron lasers (FEL) has enabled the investigation of nonlinear effects in x-ray regime. These phenomena offer high potential for applications, but require highly specialized detection schemes. In our group, we develop x-ray optics specifically dedicated to detect these nonlinear...

58. Improvement of the Slow Longitudinal Feedback System at the European XFEL

For the operation of free-electron lasers (FEL), the electron bunches provided from the gun are accelerated to almost the speed of light in various accelerator modules and compressed in bunch compressors to enable the shortest possible pulse with high current intensity for the subsequent SASE process.
The Slow Longitudinal Feedback System consists of multiple different control loops to...

87. Indirect searches for New Physics with precision calculations of Higgs couplings

After the discovery at the CERN Large Hadron Collider of a Higgs boson with a mass of about 125 GeV, the structure of the Higgs sector and the actual form of the Higgs potential still remain to a large extent uncharted. In this project, we will explore extended Higgs sectors, which could for instance be suitable for providing a possible candidate for dark matter and for explaining the...

83. Intelligent optimization for the attosecond hard X-ray pulse generation at the European XFEL

Jiawei Yan (Eur.XFEL (European XFEL))

Attosecond pulses at high photon energy are critical to study electron dynamics in atomic and molecular systems. X-ray free-electron lasers are very promising to generate high-power attosecond hard X-ray pulses. Intelligent control of the linac and undulator settings is important to enable efficient attosecond X-ray generation. In this project, we would like to explore the application of...

24. Investigation of excimer formation in purely organic molecular dyad crystals by time-resolved spectroscopy and photocrystallography

The internship will be an opportunity offered by the FS-SCS group in the photon science division of DESY to work for a limited period, on an onsite project. Interns are usually undergraduate students with physics or related background and the internship lasts for close to 6-7 weeks. Students who are invited for on-site projects are expected to work 39 hours a week and will be paid by the...

10. Investigations of ultrafast dynamical processes in highly charged matter using computer simulations

X-ray free-electron lasers (XFELs) are novel tools to investigate the properties of matter. They generate high intensity and ultrashort (i.e., tens of femtosecond duration) x-ray pulses allowing one to investigate processes with femtosecond resolution experimentally. Such pulses initiate, typically via significant ionization, complex ultrafast dynamics which leads to the need of theoretical...

65. Laboratory characterisation of TelePix2, the ROI triggering and timing sensor, for the DESY II Test Beam Facility

TelePix2 is a HV-CMOS based upgrade being used at the DESY II Test Beam facility. The fast monolithic sensor provides both region of interest triggering and precise track timing, overcoming ambiguities provided by multiple particles traversing the telescope within a single readout frame, which lasts up to 230 µs for the MIMOSA26-based telescopes. At current beam intensities, this leads to an...

67. Laboratory characterization of the H2M MAPS designed in a 65nm CMOS imaging process

The Tangerine project is studying monolithic active pixel sensors (MAPS) that are manufactured using a \SI{65}{\nano\meter} CMOS imaging process. To investigate this technology and explore the design challenges of porting a hybrid pixel detector architecture into a monolithic chip, the H2M (Hybrid-to-Monolithic) test chip has been developed.

During test beam measurements with H2M, it has...

51. Luminosity studies with Pixel Cluster Counting at the ATLAS experiment

An accurate luminosity measurement is essential for the ATLAS physics programme at the LHC. Luminosity quantifies the total number of proton-proton interactions in a dataset and by measuring it physicists are able to evaluate probabilities of interesting processes and predict background rates. ATLAS subdetectors sensitive to the number of particles produced in proton interactions are used to...

34. Machine-learning meets nonlinear optics for multicycle THz generation

High-energy pulses of multicycle THz radiation open new regimes of science and technology with applications from controlling quantum materials to driving novel, compact electron accelerators. A new methodology has recently been demonstrated for efficient and high-energy THz pulse generation using trains of tens to hundreds of optical pulses, but optimizing the properties of these trains is...

23. Machine-learning supported compression of laser pulses in a control loop

The central goal is the implementation of a neural network based self-learning loop, which connects advanced laser technology, an optimization algorithm, and an experimental feedback signal. The showcase example is the machine-learning supported compression of a femtosecond laser pulse to its Fourier limit, which is the lower limit for the pulse duration that can be technically realized for a...

16. Modeling and analyzing resonant x-ray diffraction from solids irradiated by XFEL pulses

The experiments at X-ray Free Electron Lasers (XFEL) enable the study of an unexplored regime of high-intensity x–ray–matter interaction. By means of focused XFEL pulses, it is possible to create a transient state of matter where crystalline order is preserved while atoms are core-excited. Such atoms couple strongly to x-ray radiation resonant with core-level transition, hence creating a...

99. Multi-method characterization of conducting polymer thin films for thermoelectric applications

Poly(3-hexylthiophen-2,5-diyl) (P3HT) is one of the most prominent semiconducting, conjugated polymers in the fields of organic electronics and photovoltaics. Besides its high electric conductivity, it shows thermoelectric properties when doped with metal chlorides or nanoparticles, for example gold (Au). Thin thermoelectric P3HT films are of utmost importance and interest for future...

91. Noble metal sputter deposition on nanostructured polymer templates

Vacuum deposition of functional thin films has applications in numerous fields ranging from structural materials to solar cells, sensors, catalysis and medicine. Time-resolved X-ray scattering under high-speed industrial conditions in combination with spectroscopic methods provide ultimate insights to answer crucial questions about structure-property relationships. This knowledge is essential...

30. Novel photocathodes for CW SRF L-band electron source for EuXFEL

For future CW / HDC upgrade of the EuXFEL the CW L-band electron source is under development at DESY. Photocathode is critical component of the electron source. When it comes to complex SRF technology, finding suitable material with sufficient QE and compatible with clean SRF environment becomes challenging. Therefore, special RnD for novel photocathode development suitable for integration in...

63. Numerical Studies to Reduce Beam Intensities at the High Intensity Test Beam-Facility PRIMA

The PRIMary-beam test Area (PRIMA), formerly a transport beamline from the DESY synchrotron to DORIS, is currently being commissioned to serve as a high-rate electron test beam line.
When DESY is not used to accelerate electron bunches for the PETRA III synchrotron radiation facility, bunches can be extracted towards the PRIMA beam line, delivering up to 3x1E10 electrons for irradiation...

26. Online data validation and rejection during experiments

The student will join the new Scientific Computing group in Photon
Science, and implement data classification and validation algorithms
using machine learning techniques, to be used at PETRA III
beamlines.

57. Phoenix event display for ILD

The FTX Software (SFT) group is actively involved in the Key4hep project, which aims to develop common software for future collider projects. One of the core responsibilities of the group in this context is the migration of existing workflows for the International Large Detector (ILD) concept to Key4hep based software. An event display is a tool that allows physicists to view the generated and...

93. Plasma wakefield acceleration and focusing for PETRA IV

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 and focusing provide high accelerating and focusing gradients (see [1, 3, 4]), promise compact plasma accelerators and plasma lenses of high-brightness and high-energy electron and...

85. Precision in New Physics searches at future electron-positron and muon colliders

Future colliders (electron-positron colliders like CEPC, CLIC, FCC-ee, ILC, muon colliders MuC, and hadron colliders FCC-hh) are being designed to tackle several riddles in modern particle physics: dark matter, missing CP violation, neutrino masses, the origin of the flavor structure and electroweak symmetry breaking. To determine their physics potential, precise predictions for new physics...

86. Precision investigations of trilinear Higgs couplings and applications for collider processes

After the discovery at the CERN Large Hadron Collider of a Higgs boson with a mass of about 125 GeV, the structure of the Higgs sector and the actual form of the Higgs potential still remain to a large extent uncharted. In this project, we will explore extended Higgs sectors, which could for instance be suitable for providing a possible candidate for dark matter and for explaining the...

7. Rapid prototyping of glass-polymer-hybrid injection devices for time-resolved serial crystallography

The work would include the screening of 2PP process parameters to obtain reproducible fully glass-based micromixers and nozzles with the Nanoscribe; device assembly in the nozzle lab; jetting tests via high-speed videography under brightfield as well as fluorescence microscopy mixing studies and particle image velocimetry with the laser illumination.

49. Research Facilities 2.0 - Sustainable Computing

The EU funded project Research Facilities 2.0 has the aim to make large scientific infrastructures and institutes more sustainable.
Within the project green and sustainable concepts for the computing infrastructures at DESY for scientiffic data storage and data analysis shall be developed. This has to happen in close collaboration among the various teams in IT, but also within DESY and other...

52. Revealing the structure of nanoparticles in mesocrystalline grains using Angular X-ray Cross-correlation Analysis (AXCCA)

This project aims to elucidate the intricate structure of colloidal crystals formed by nanoparticles covered by proteins. These crystals will be characterized using small-angle X-ray scattering (SAXS). We aim to utilize the Angular X-ray Cross-Correlation Analysis (AXCCA) technique to analyse the ordering of nanoparticles within the superlattices. Our focus lies on understanding the...

60. Sensitivity study for a measurement of decay-time-dependent CP-violation using $B^0\to \pi^0 \pi^0$ at Belle II

CP-asymmetry is expected to explain the huge imbalance between matter and antimatter in our universe. The CP-asymmetry observed so far at particle or nuclear physics experiments is too small to explain this imbalance. We therefore expect new, yet-unknown sources of CP-violation to exist. One way to find hints for these new sources is to precisely measure differences in the decay rates of $B^0$...

8. Simulating Ultrafast Photoexcitation Dynamics in Gas- and Liquid-Phase Furfural

Ultrafast ring-opening dynamics is considered an important channel for the non-radiative decay of an electronically excited state in a number of molecules.
In this project, the ultrafast ring-opening of furfural triggered by a 266nm UV-light pulse is studied theoretically. It is explored how the photo-induced dynamics can be probed using ultrafast XUV absorption spectroscopy.
The project...

71. Simulation and analysis of novel detectors to search for new physics

Beam dump experiments have become of particular interest in the search for new physics beyond the standard model of particle physics. High-energy electrons, protons, or photons are dumped on a solid target where new particles could be produced. In the new physics model we are testing, these particles can be scalar or pseudo-scalar, and photons offer the cleanest way of performing such a...

66. Simulations and Measurements of Backgrounds at the BabyIAXO Site

As part of the axion/ALP search program at DESY, the next generation axion helioscope BabyIAXO aims to discover axions/ALPs produced in our Sun. The experiment will be located in the underground cavern of the HERA South hall and aims to be sensitive to a single (X-ray) photon per year. With respect to this goal, the in-situ background levels have to be understood and characterised in detail to...

78. Software Tool for Automatization of Beamlines

Performing an experiment at the European XFEL requires the tuning of several components, including mirrors and motors, with the goal of ensuring that the beam is accurately aligned to the sample for a given choice of experimental parameters. However, this process reduces considerably the time used to collect data, and therefore the chances of success in addressing a given scientific question....

96. Spatial analysis and stabilization of multi-octave spanning laser pulses in an attosecond beamline

Detecting and analyzing beam profiles from sources spanning several octaves is challenging, but at the same time crucial to perform attosecond science experiments in a deterministic way.
You will gain insights into state-of-the-art applications of nonlinear optics and the limits of the technology in waveform synthesis. The task includes detailed beam analysis up to large-scale beam...

61. Study of improvements of the tracking of very low transverse momentum particles in the Belle II experiment

Collisions produced at the interaction region of the Belle II experiment produce charged final state particles with a broad momentum spectrum from a few tens of MeV/c to several GeV/c. Highly efficient reconstruction of these charged particles as tracks with a low fake rate are essential for the success of the physics programme of Belle II. So far, the track finding efficiency is significantly...

79. Superconducting Undulators

For more than 5 years, superconducting undulators (SCUs) using NbTi as conductor have been successfully delivering X-rays in storage rings. The European X-Ray Free-Electron Laser Facility (XFEL) plans to demonstrate the operation of SCUs in X-ray free-electron lasers (FELs). For the same geometry, SCUs can reach a higher peak field on the axis with respect to all other available technologies,...

3. Superradiant THz radiation generation at XFEL

STERN (Superradiant THz radiation generation) is a project funded by the European XFEL to develop and provide a high-power terahertz source to enable pump-probe science with the existing high-power X-ray beam. This evasive region of the electromagnetic spectrum has a wide range of applications facilitating the exploration of life and matter science. STERN will use both diffraction targets and...

6. Synthesis, characterisation and application of 1D, 2D and 3D mixed-ligand metal-organic frameworks

Metal-organic frameworks (MOFs) are modular porous materials synthesized from metal cluster nodes and organic linkers that connect these nodes. These materials have been an object of extensive study for the past two decades, since their ultrahigh porosity (up to 90% free volume) and enormous internal surface areas (extending beyond 6 000 m2/g) make them interesting for potential applications...

76. Tensor Networks for Computational Fluid Dynamics

This project aims to compare the tree tensor network ansatz against the matrix product states ansatz in solving partial differential equations within the realm of computational fluid dynamics. The performance analysis will be based on the compressibility of each ansatz as compared to direct numerical simulation.

84. Testbeam characterisation of the silicon-strip modules in ATLAS Inner tracker (ITk) for High Luminosity phase of the Large Hadron Collider (HL-LHC)

The Large Hadron Collider (LHC) is planning to be upgraded to the High-Luminosity LHC (HL-LHC). The protons in HL-LHC will collide with each other at an energy up to 14 TeV. And the number of collisions will be increased by a factor of between 5 and 7.5 with respect to the nominal LHC design. The HL-LHC will make it possible to study the fundamental building blocks of matter and the forces...

100. Tests of SiPM-on-Tile modules for the CMS HGCAL

Our group works on the development of highly granular hadronic calorimeters based on small scintillator tiles read out by Silicon Photomultipliers (SiPMs). This “SiPM-on-tile” technology will be used for the upgrade of the calorimeter endcap of the CMS detector for HL-LHC. An important ingredient for these calorimeters is the readout electronics, which is fully integrated into the detector...

69. The more the merrier: searching for Higgs boson twins and triplets with ATLAS

An intriguing property of the Higgs field is its ability to interact with itself. Experimentally, the trilinear (triple-Higgs vertex) and quartic (quadruple-Higgs vertex) self-interactions can be probed in proton-proton collisions at the LHC that result in two or three Higgs bosons. These rare and hard-to-identify processes not only provide unique access to the full shape of the Higgs...

97. Transport and coupling of single-cycle THz pulses in novel THz-driven electron accelerators

THz-driven electron accelerators represent a new concept for the future of electron sources with novel capabilities related to the ultra-high field strengths and short wavelengths achievable with THz-frequency electromagnetic pulses. The new technology comes with new challenges, for example in transporting and coupling ultra-broadband mm-wave radiation. In this project you learn a combination...

29. Twin-bunch generation in the European XFEL injector

A twin-bunch scheme, which accelerates two electron bunches with small time separation, is important for generating high intensity two-color free-electron laser (FEL) pulses. It can also be used in beam-driven plasma acceleration to boost the beam energy of the witness bunch. At the European XFEL, such capability of generating twin bunches from the injector is enabled by the NEPAL-X laser that...

82. ultrafast time-resolved optical absorption spectroscopy studies of solvated molecules

Our group focusses on understanding photochemical reactivity in molecular systems with ultrafast x-ray and optical sources. In particular, we concentrate on smaller molecular model systems in solution as well as complex transition metal coordination compounds with relevance for e.g. solar energy or photoswitching applications, with the goal of tracking and controlling their excited state...

53. Uncovering rare B meson decays with photons at Belle II

B meson decays to final states that include a photon offer a unique probe into the quark-level transition b→s𝛾. In the Standard Model (SM), this transition occurs through a loop-induced process, making it very rare and sensitive to contributions beyond the SM. Additionally, measuring the photon energy spectrum is sensitive to the mass of the b-quark as well as non-perturbative...

77. Understanding the structure of nanopatterns prepared by ion beam erosion using grazing incidence small angle x ray scattering

Grazing incidence small angle x-ray scattering (GISAXS) is a powerful technique for studying nanostructures. By analyzing scattered x-rays at grazing incidence, GISAXS provides valuable insights into the size, shape, and arrangement of nano-scale materials. In this work surface morphology (nanoripples, nanocones) of different nanopatterned morphologies prepared by ion beam erosion will be...

22. Upgrading an x-ray attosecond beamline for time-resolved experiments

In the attosecond science group at CFEL (https://atto.cfel.de), we generate ultrashort laser pulses with attosecond (1 as = 10−18 s) or few-femtosecond (1 fs = 10−15 s) duration. These pulses are used to trigger ultrafast dynamics in a variety of systems, from bio-relevant molecules to clusters and nanosystems, and to follow in real-time how the atoms and electrons move and interact. With our...

31. UV laser beamline diagnostic @REGAE

For the UV GUN laser beamline @REGAE a highly precise virtual cathode diagnostic is required to meet the high demands to generating and control of ultra low intensity electron bunches. The design is done and the diagnostic has to be tested in the REGAE laser lab and later set up at the UV laser beamline in cooperation with experienced members of the group. If the diagnostic could be...

5. Wavefront Engineering for Reduction of Vibration Artifacts in Ptychography

X-ray Ptychography is a modern microscopy technique in which the image is not directly measured on the detector, but reconstructed with a phase retrieval algorithm from coherent diffraction images. The performance of ptychography can be enhanced by using taylor-made engineered wavefronts, e.g. vortex beams. Vibrations of the experimental setup are a known limiting factor in ptychographic...

80. Wireless Sensor Network for Monitoring Environmental Parameters in the Detector lab of the European XFEL

Environmental parameters such as temperature, pressure, and humidity play a vital role in many laboratory experiments and procedures. Accurate monitoring of these parameters can help to maintain the optimal conditions required for the success of the experiments. This project aims to develop a wireless sensor network that will monitor these environmental parameters and transmit the data...

9. X-ray multiphoton ionization: direct vs. sequential processes

When an atom interacts with an intense x-ray pulse generated from x-ray free-electron laser facilities, it undergoes x-ray multiphoton ionization, which is characterized primarily by a sequence of one-photon absorption and accompanying relaxation events. It is known that the contribution of direct two-photon absorption in this scheme is negligible, because the one-photon absorption channel in...

14. XRF image de-noising

The project is about de-noising of xray fluorescence (XRF) images from the P06 scanning microscopy beamline. While several contrast modes are available at P06, the main workhorse of the beamline is xray fluorescence. An important figure of merit for the beamline is how quickly images can be acquired. Acquiring faster comes at the cost of nosier images. We would like to investigate whether we...