Academic Interests
- Experimental nuclear physics:
- Oslo Method for Nuclear level density and gamma-ray strength function
- Nuclear Fission process focusing on prompt fission gamma-rays
- Nuclear Disarmament Verification
- Uncertainty analysis with Bayesian statistics:
- Bayesian inference
- Markov Chain Monte Carlo
- Nested Sampling
- Monte Carlo Particle Transport Simulations (GEANT4, MCNP, MCNPX)
- Inverse problems like detector response unfolding
Higher education
- UiO PhD studies, 2017 -
- Master of Subatomic Physics, 2016, UiO
- Bachelor of Physics, 2013, University of Hamburg
Teaching experience at UiO
- Bachelor level:
- FYS2140 (2x): Quantum physics
- FYS3520: Nuclear physics
- FYS3500 (2x): Nuclear and particle physics
- Master level:
- Supervision of Master students
- Summer school on advanced nuclear reactions and applications in astrophysics (@ Stellenbosch University, South Africa)
- FYS4580: Nuclear Technology
- FYS4505: Methods and instrumentation for nuclear and particle physics - University of Oslo
Employment history
- Norwegian Radiation Protection Authority, Oslo (Advisory)
- Centre for Science and Peace Research, University of Hamburg (Research Assistant)
- Prepcom for the Comprehensive Nuclear-Test-Ban Treaty (Internship)
Emneord:
radiation physics,
nuclear physics,
nuclear structure,
gamma,
Bayesian Statistics,
Simulations,
fission,
Bayesian inference
Publikasjoner
-
-
-
-
-
-
-
-
-
-
-
-
Gjestvang, Dorthea; Siem, Sunniva; Zeiser, Fabio; Randrup, Jørgen; Vogt, Ramona & Wilson, Jonathan Nicholas
[Vis alle 19 forfattere av denne artikkelen]
(2021).
Excitation energy dependence of prompt fission γ-ray emission from 241Pu*.
Physical Review C.
ISSN 2469-9985.
103(3).
doi:
10.1103/PhysRevC.103.034609.
Fulltekst i vitenarkiv
Vis sammendrag
Prompt fission γ rays (PFGs) resulting from the 240Pu(d,pf) reaction have been measured as a function of fissioning nucleus excitation energy Ex at the Oslo Cyclotron Laboratory. We study the average total PFG multiplicity per fission, the average total PFG energy released per fission, and the average PFG energy. No significant changes in these characteristics are observed over the range 5.75
-
-
-
Zeiser, Fabio; Tveten, Gry Merete; Bello Garrote, Frank Leonel; Guttormsen, Magne Sveen; Larsen, Ann-Cecilie & Ingeberg, Vetle Wegner
[Vis alle 8 forfattere av denne artikkelen]
(2021).
The gamma-ray energy response of the Oslo Scintillator Array OSCAR.
Nuclear Instruments and Methods in Physics Research Section A : Accelerators, Spectrometers, Detectors and Associated Equipment.
ISSN 0168-9002.
985.
doi:
10.1016/j.nima.2020.164678.
Fulltekst i vitenarkiv
-
-
-
-
-
Ingeberg, Vetle Wegner; Siem, Sunniva; Wiedeking, Mathis; Sieja, Kamila; Bleuel, D.l. & Brits, C.P.
[Vis alle 29 forfattere av denne artikkelen]
(2020).
First application of the Oslo method in inverse kinematics.
European Physical Journal A.
ISSN 1434-6001.
56.
doi:
10.1140/epja/s10050-020-00070-7.
Fulltekst i vitenarkiv
Vis sammendrag
The γ-ray strength function (SF) and nuclear level density (NLD) have been extracted for the first time from inverse kinematic reactions with the Oslo method. This novel technique allows measurements of these properties across a wide range of previously inaccessible nuclei. Proton–γ coincidence events from the d(⁸⁷Kr,p)⁸⁶Kr reaction were measured at iThemba LABS and the γSF and NLD in ⁸⁶Kr was obtained. The low-energy region of the γSF is compared to shell-model calculations, which suggest this region to be dominated by M1 strength. The γSF and NLD are used as input parameters to Hauser–Feshbach calculations to constrain (n,γ) cross sections of nuclei using the TALYS reaction code. These results are compared to ⁸⁶Kr(n,γ) data from direct measurements.
-
-
-
-
-
-
Kullmann, Ina Kristine Berentsen; Larsen, Ann-Cecilie; Renstrøm, Therese; Beckmann, Kristine Sønstevold; Bello Garrote, Frank Leonel & Crespo Campo, Lucia
[Vis alle 13 forfattere av denne artikkelen]
(2019).
First experimental constraint on the 191Os(n,γ) reaction rate relevant to s-process nucleosynthesis
.
Physical Review C.
ISSN 2469-9985.
99(6).
doi:
10.1103/PhysRevC.99.065806.
Fulltekst i vitenarkiv
Vis sammendrag
The nuclear level density and
γ
-decay strength of
192
Os
have been extracted using particle-
γ
coincidence data from the
192
Os
(
α
,
α
′
γ
)
192
Os
reaction by means of the Oslo method. The level density is found to be a rather smooth function of excitation energy, approximately following the constant temperature model. The
γ
-decay strength is compared to photoneutron cross-section data above the neutron separation energy, and to
E
1
and
M
1
strengths for nuclei in this mass region derived from primary transitions following neutron capture. Our results are in good agreement with these previous data and draw a consistent picture of the
γ
-strength function in the range
E
γ
≈
1.5
–
6
MeV
. Using the measured nuclear level density and
γ
-decay strength as input to the nuclear-reaction code talys, we provide the first experimentally constrained Maxwellian-averaged cross section (MACS) for the
191
Os
(
n
,
γ
)
192
Os
reaction relevant to
s
-process nucleosynthesis. The systematic uncertainties introduced by the normalization procedure of the level density and
γ
-strength function were investigated and propagated to the calculated Maxwellian-averaged cross section. The obtained result of the Maxwellian-averaged cross section at
k
B
T
=
30
keV
,
⟨
σ
⟩
n
,
γ
=
1134
±
375
mb
, is in very good agreement with the theoretical estimate provided by the KADoNiS project, giving experimental support to the adopted KADoNiS value. Good agreement is also found with MACS values obtained from other libraries, such as TENDL-2017, ENDF/B-VII.0, and JEFF.
-
-
-
-
-
-
-
-
-
-
-
-
-
-
Se alle arbeider i Cristin
-
-
Ingeberg, Vetle Wegner; Siem, Sunniva; Wiedeking, M.; Abrahams, Kenzo John; Arnswald, K. & Bello Garrote, Frank Leonel
[Vis alle 36 forfattere av denne artikkelen]
(2019).
Inverse-Oslo Method – a tool for expanding our understanding of the r-process.
-
Guttormsen, Magne Sveen; Larsen, Ann-Cecilie; Midtbø, Jørgen E.; Crespo Campo, Lucia; Görgen, Andreas & Ingeberg, Vetle Wegner
[Vis alle 11 forfattere av denne artikkelen]
(2017).
Gamma-widths, lifetimes and fluctuations in the nuclear quasi-continuum.
-
Zeiser, Fabio
(2021).
Uncertainty quantification for nuclear level densities and y-ray strength functions from the Oslo method and beyond
.
Universitetet i Oslo.
ISSN 1501-7710.
-
Bleuel, Darren L.; Anderson, S; Bernstein, L. A.; Brand, C. A.; Brown, J. A. & Caggiano, J. A.
[Vis alle 23 forfattere av denne artikkelen]
(2017).
Status Report of Neutron Radiation Effects and Damage to Neutron Imaging System Equipment at Lawrence Livermore National Laboratory.
Lawrence Livermore National Laboratory (LLNL).
Vis sammendrag
To reduce potential time-consuming outages at a neutron imaging facility under construction at Lawrence Livermore National Laboratory, a variety of equipment was irradiated with a high-intensity neutron beam at Lawrence Berkeley National Laboratory’s 88-inch cyclotron. A broad neutron spectrum was created by deuteron breakup and equivalent damage rate expected at the neutron imaging facility calculated. A number of components failed quickly under neutron irradiation while others functioned without negative effect. Recommendations to relocate, shield, or replace the failed components are given.
Se alle arbeider i Cristin
Publisert
7. aug. 2017 14:44
- Sist endret
5. apr. 2020 12:09