Conveners
Sektionen för kärnfysik: AF Borgen, Kerstins rum
- Joakim Cederkall (Lund University (SE))
Isospin symmetry is known to be a very useful, but approximate symmetry of atomic nuclei, violated by electromagnetic interactions between nucleons. Modern experiments exploring structure and decay of neutron-deficient nuclei and nuclei along N=Z line continue to bring new information on various features related to isospin-symmetry breaking. In this talk we will review the current status of...
By studying the neutron skin thickness across the Sn isotopic chain, one can gain a rich insight into the slope of the density dependence of the symmetry energy. A novel method using the total neutron-removal cross section (𝜎𝛥N) has been shown to be highly sensitive to the slope, with a 1% change in 𝜎𝛥N corresponding to a variation of L=±5 MeV. Experiments that have been performed at GSI at...
Effective field theories (EFTs) of the strong nuclear interaction is imbued with uncertainty stemming from, e.g., experimental errors and truncation of the EFT expansion. Theoretical predictions of nuclear observables should thus be considered---and presented---as probability density functions (PDFs) rather than scalar values. Working in a Bayesian framework, we have inferred PDFs for the EFT...
Nucleon-deuteron (Nd) scattering data provides direct insight into the three-nucleon forces (3NFs) of chiral effective field theory ($\chi$EFT). Wave-packet continuum discretization (WPCD) is a method that can efficiently approximate Nd scattering wave functions. In this talk I present a study where we developed a WPCD-code and sampled posterior predictive distributions (PPDs) of Nd...
An experimental campaign focusing on isospin-symmetry and proton emission in the upper fp shell was performed at Argonne National Laboratory (ANL) in 2020, with the nuclear structure group from Lund University leading three out of five experiments. The overarching goal was to perform in-beam high-resolution particle- and γ-ray coincidence spectroscopy. The first experiment focused on particle...
Fission barriers in neutron-rich nuclei provide essential input for understanding the astrophysical r-process, yet are extremely challenging to measure. Using direct kinematics is not possible for the investigation of short-lived isotopes. However, high-resolution studies of radioactive beams in inverse kinematics are feasible through the use of a solenoidal spectrometer. By exploiting the...
The production of antihyperon-hyperon pairs in antiproton-proton collisions is an excellent probe for studying the strong interaction in the non-perturbative regime. Here, the relevant degrees of freedom are unclear. The self-analysing decay of hyperons provides us with a way to investigate reaction dynamics by reconstructing spin observables. Furthermore, hyperon spectroscopy enables us to...
Understanding the structure of hadrons is the core mission of hadron physics. Electromagnetic form factors provide us an angle to understand the structure of hadrons. For instance, in the history of particle physics, by studying the electromagnetic form factors of electron-proton scattering one inferred the existence of partons, namely, quarks. In this talk, I will present a model independent...
All matter that we encounter in our daily lives is made up of baryons. These, in turn, are built from quarks held together by the strong force. Because of the nature of the strong force, it is challenging to understand the interactions between the quarks and how these give the baryons the properties that we can observe. Despite a century of intense effort, the mechanisms behind properties like...
During this spring the HADES experiment at GSI in Darmstadt, Germany had a total of 30 days of proton beam, producing pp reactions at 4.5 GeV beam kinetic energy. The main goal of this beam time is to study hyperon production and their electromagnetic decays. It is one of the FAIR Phase-0 projects, using FAIR equipment at the GSI facility. For this run the HADES spectrometer was accomplished...
Understanding the physics and inner workings of neutron stars has been a longstanding issue since their discovery in 1967. These incredibly dense stellar objects are formed from the collapse of supergiants, finding equilibrium by a neutron degeneracy arising in its interior. The development of accurate equation of state models has been hindered by the energetically favoured appearance of...
Flerovium isotopes (element Z=114) were produced in the fusion-evaporation reactions $^{48}$Ca+$^{242,244}$Pu in a decay spectroscopy experiment conducted at the GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt, Germany. Within 18 days of beam time, 29 flerovium decay chains were identified by means of correlated implantation, $\alpha$-decay, and spontaneous fission events. The...
