T. Braunroth
A5030881248- Nuclear physics research studies
- Atomic and Molecular Physics
- Nuclear Physics and Applications
- Advanced Chemical Physics Studies
- Astronomical and nuclear sciences
- Advanced NMR Techniques and Applications
- Radiation Therapy and Dosimetry
- Atomic and Subatomic Physics Research
- Quantum Chromodynamics and Particle Interactions
- Electron and X-Ray Spectroscopy Techniques
- Quantum, superfluid, helium dynamics
- Particle accelerators and beam dynamics
- Nuclear reactor physics and engineering
- Inorganic Fluorides and Related Compounds
- Isotope Analysis in Ecology
- Superconducting Materials and Applications
- Graphite, nuclear technology, radiation studies
- X-ray Spectroscopy and Fluorescence Analysis
- Particle Detector Development and Performance
- Particle physics theoretical and experimental studies
- Sensor Technology and Measurement Systems
- Radiation Detection and Scintillator Technologies
- Rare-earth and actinide compounds
- Computational Physics and Python Applications
- Flow Measurement and Analysis
University of Cologne
2014-2023
Physikalisch-Technische Bundesanstalt
2019-2022
Gesellschaft für Anlagen und Reaktorsicherheit
2020-2021
University of Manchester
2018
The transition rates from the yrast ${2}^{+}$ and ${4}^{+}$ states in self-conjugate $^{72}\mathrm{Kr}$ nucleus were studied via lifetime measurements employing GRETINA array with a novel application of recoil-distance method. large collectivity observed for ${4}^{+}\ensuremath{\rightarrow}{2}^{+}$ suggests prolate character excited states. reduced previously reported ${2}^{+}\ensuremath{\rightarrow}{0}^{+}$ was confirmed. irregular behavior points to occurrence rapid oblate-prolate shape...
Transition strengths for decays from low-lying states in A ∼ 70 nuclei have been deduced lifetime measurements using the recoil distance Doppler shift technique. The results confirm collectivity previously reported 21+→0gs+ decay 68Se and reveal a relative decrease 70Br. This trend is reproduced by shell model calculations GXPF1A interaction an fp space including Coulomb, spin-orbit isospin non-conserving interactions. 31+→21+ 70Br found to very small B(M1) value, which consistent with...
Lifetimes of the first excited ${2}^{+}$ and ${4}^{+}$ states in extremely neutron-deficient nuclide $^{172}\mathrm{Pt}$ have been measured for time using recoil-distance Doppler shift recoil-decay tagging techniques. An unusually low value ratio $B(E2:{4}_{1}^{+}\ensuremath{\rightarrow}{2}_{1}^{+})/B(E2:{2}_{1}^{+}\ensuremath{\rightarrow}{0}_{\mathrm{gs}}^{+})=0.55(19)$ was found, similar to a handful other such anomalous cases observed entire Segr\'e chart. The observation adds cluster few...
Lifetimes of the 21+ states in 44Ti, 48,50Cr, and 52Fe were determined with high accuracy exploiting recoil distance Doppler-shift method. The reduced E2 transition strengths 44Ti differ considerably from previously known values. A systematic increase collectivity is found for N=Z nuclei compared to neighboring isotopes. B(E2) values along Ti, Cr, Fe isotopic chains are shell-model calculations employing established interactions 0f1p shell, as well a novel effective Hamiltonian starting...
The lifetime of the first excited 2+ state in neutron deficient nuclide 108Te has been measured for time, using a combined recoil decay tagging and distance Doppler shift technique. deduced reduced transition probability is B(E2;0g.s.+→2+)=0.39−0.04+0.05e2b2. Compared to previous experimental data on tellurium isotopes, new point constitutes large step (six neutrons) toward N=50 shell closure. In contrast what earlier reported light tin our result does not show any enhanced with respect...
Reduced quadrupole transition probabilities for low-lying transitions in neutron-rich $^{84,86}\mathrm{Se}$ are investigated with a recoil distance Doppler shift (RDDS) experiment. The experiment was performed at the Istituto Nazionale di Fisica Nucleare (INFN) Laboratori Nazionali Legnaro using Cologne Plunger device RDDS technique and AGATA Demonstrator array $\ensuremath{\gamma}$-ray detection coupled to PRISMA magnetic spectrometer an event-by-event particle identification. In...
Lifetimes of ${2}_{1}^{+}$ and ${4}_{1}^{+}$ states in $^{190,192,194,196}\mathrm{Hg}$ some negative parity band members were measured using the $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ fast-timing technique with a high-purity germanium ${\mathrm{LaBr}}_{3}$(Ce) detector array. The excited populated via fusion-evaporation reactions Tandem Van de Graaff accelerator Institute Nuclear Physics Cologne, Germany. derived reduced transition probabilities...
The heaviest N=Z doubly-magic nucleus, $^{100}$Sn, and the neighboring nuclei offer unique opportunities to investigate properties of nuclear interaction in extreme conditions. In particular, Cd isotopes are expected present features similar those found Sn isotopic chain, since they have only two proton holes Z=50 shell. this manuscript, lifetime measurements low-lying states even-mass $^{102-108}$Cd is presented. Thanks powerful detection capabilities AGATA array VAMOS++ spectrometer,...
Background: In neutron-rich nuclei around N=40 rapid changes in nuclear structure can be observed. While Ni68 exhibits signatures of a doubly magic nucleus, experimental data along the isotopic chains even more exotic Fe and Cr isotopes—such as excitation energies transition strengths—suggest sudden rise collectivity toward N=40. Purpose: Reduced quadrupole strengths for low-lying transitions Cr58,60,62 are investigated. This gives quantitative new insights into evolution region close to...
Lifetimes of the excited states in neutron-rich $^{52,54}\mathrm{Ti}$ nuclei, produced a multinucleon-transfer reaction, were measured by employing Cologne plunger device and recoil-distance Doppler-shift method. The experiment was performed at Grand Acc\'el\'erateur National d'Ions Lourds facility using Advanced Gamma Tracking Array for $\ensuremath{\gamma}$-ray detection, coupled to large-acceptance variable mode spectrometer an event-by-event particle identification. A comparison between...
Background: Shape coexistence in the $Z\ensuremath{\approx}82$ region has been established mercury, lead, and polonium isotopes. For even-even mercury isotopes with $100\ensuremath{\le}N\ensuremath{\le}106$ multiple fingerprints of this phenomenon are observed, which seems to be no longer present for $N\ensuremath{\ge}110$. According a number theoretical calculations, shape is predicted $^{188}\mathrm{Hg}$ isotope.Purpose: The aim work was measure lifetimes excited states infer their...
This work presents an attempt to addressing the issue of RBE variation in a spread-out Bragg peak (SOBP) protons based on nanodosimetric track structure analysis. Ionization has been simulated using Geant4-DNA for 100 MeV initial energy propagating water. The frequency distribution ionization clusters formed target volumes corresponding 10 base-pairs segment DNA was obtained as function radial distance between and proton trajectory set positions along path. Radial dependence parameters...
Lifetime measurements of excited states in 178Hg have been performed using the 103Rh(78Kr,p2n) reaction at a beam energy 354 MeV. The recoil-decay tagging (RDT) technique was applied to select nuclei and associate prompt γ rays with correlated characteristic ground-state α decay. Lifetimes four lowest yrast determined recoil distance Doppler-shift (RDDS) method. experimental data are compared theoretical predictions focus on shape coexistence. results confirm shift deformed prolate...
Self-conjugate nuclei in the A≈70–80 region have attracted a great deal of attention due to phenomena such as shape coexistence and increasing collectivity along N=Z line. We investigate structure this through lifetime measurements using GRETINA array. The first implementation Differential Recoil Distance Doppler Shift technique with fast radioactive beams is demonstrated verified measurement well-known B(E2;21+→01+) transition strength 74Kr. method then applied determine 74Rb, heaviest...
This work presents a detailed investigation into the nanodosimetric properties of track structure protons in water at energies relevant for proton radiotherapy. The ionization component tracks had been simulated previous using Geant4-DNA start between 1 MeV and 100 MeV. From simulation results, frequency distribution clusters formed nanometric target volumes was obtained dependence impact parameter trajectory with respect to center. In core, targets cylindrical shape size comparable short...
The 278-keV $M2$ $\ensuremath{\gamma}$ decay from the $\ensuremath{\nu}{h}_{11/2}$ isomeric state in ${}^{113}$Xe has been observed for first time using recoil-isomer tagging technique. half-life of isomer measured to be 6.9(3) $\ensuremath{\mu}$s. derived $B(M2)$ value is agreement with trend systematic measurements transition strengths neutron-deficient tellurium and tin isotopes. lifetime excited band recoil distance Doppler-shift method. extracted $B(E2)$ compared theoretical CD-Bonn...
Lifetime measurements have been performed using the $^{98}\mathrm{Mo}$($^{86}\mathrm{Kr},4n$)$^{180}\mathrm{Pt}$ reaction at a beam energy of 380 MeV, and recoil distance Doppler-shift method. In second experiment $^{168}\mathrm{Yb}$($^{16}\mathrm{O},4n$)$^{180}\mathrm{Pt}$ 88 MeV Ge-gated $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ fast timing technique was used to determine lifetimes. Lifetimes four lowest yrast states $^{180}\mathrm{Pt}$ determined. The experimental data are...
Lifetimes of low-lying excited states in the νi13/2+ bands neutron-deficient osmium isotopes 169,171,173Os have been measured for first time using recoil-distance Doppler shift and recoil-isomer tagging techniques. An unusually low value is observed ratio B(E2;21/2+→17/2+)/B(E2;17/2+→13/2+) 169Os, similar to "anomalously" values B(E2;41+→21+)/B(E2;21+→0gs+) previously several transitional rare-earth nuclides with even numbers neutrons protons, including neighbouring 168,170Os. Furthermore,...
The lifetime of the $(11/{2}^{+})$ state in band above proton-emitting $(3/{2}^{+})$ $^{113}\mathrm{Cs}$ has been measured to be $\ensuremath{\tau}=24(6)$ ps from a recoil-decay-tagged differential-plunger experiment. was used deduce deformation states using wave functions nonadiabatic quasiparticle model independently calculate both proton-emission and electromagnetic $\ensuremath{\gamma}$-ray transition rates as function deformation. only quadrupole deformation, which able reproduce...
Level lifetimes of the yrast $(5/{2}^{\ensuremath{-}})$ to $13/{2}^{\ensuremath{-}}$ states in neutron-rich nucleus $^{53}\mathrm{Ti}$, produced a multinucleon-transfer reaction, have been measured for first time. The recoil distance Doppler-shift method was employed and excited were extracted by lineshape analysis aided Geant4-based Monte-Carlo simulations. experiment performed at Grand Acc\'el\'erateur National d'Ions Lourds facility Caen, France, using Advanced Gamma Tracking Array...
Lifetime measurements of excited states in doubly-magic 56Ni have been performed exploiting the Doppler-shift attenuation method order to determine reduced transition probabilities. For 41+ and 61+ states, deduced B(E2) values are compared with results from shell-model calculations employing GXPF1A modern PFSDG-U interactions. In addition, valence ab-initio were using a novel realistic Hamiltonian derived chiral perturbation theory including three-body potential contributions confronted...
We report on a study of the $\ensuremath{\alpha}$-decay fine structure and associated ${E}_{\ensuremath{\alpha}}\ensuremath{-}{E}_{\ensuremath{\gamma}}$ correlations in decays $^{171,172}\mathrm{Os}$ $^{171,172,174}\mathrm{Ir}$. In total, 13 new energy lines have been resolved, three $\ensuremath{\gamma}$-ray transitions observed following decay branches to $^{168}\mathrm{Re}$ $^{167}\mathrm{W}$. The weak branch from bandhead $\ensuremath{\nu}{i}_{13/2}$ band $^{171}\mathrm{Os}$ this work...
Lifetimes or lifetime limits of a small number excited states the sulfur isotopes with mass numbers $A=35$, 36, 37, and 38 have been measured using differential recoil-distance method. The were populated in binary grazing reactions initiated by beam $^{36}\mathrm{S}$ ions energy 225 MeV incident on thin $^{208}\mathrm{Pb}$ target which was mounted Cologne plunger apparatus. combination PRISMA magnetic spectrometer an early implementation AGATA $\ensuremath{\gamma}$-ray tracking array used to...
Transition probabilities of intermediate-spin yrast and non-yrast excitations in 80,82Se were investigated a recoil distance Doppler-shift (RDDS) experiment performed at the Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali Legnaro. The Cologne Plunger device for deep inelastic scattering was used RDDS technique combined with AGATA Demonstrator array γ-ray detection coupled to PRISMA magnetic spectrometer an event-by-event particle identification. In 80Se, level lifetimes (6+1)...