Fysikermøtet 2021

Europe/Oslo
Universitetet i Stavanger

Universitetet i Stavanger

Kristine Bonnevies vei 22, 4021 Stavanger
Description

Update May 19th 2021:

In view of the stated government timeline for recommendations on domestic travel, as well as current national, local and institutional guidelines, we have decided to turn Fysikermøte into a fully digital event. Therefore:

  • The Fysikermøte will be virtual, with all talks streamed via Zoom.
  • We encourage speakers to investigate options to give their presentation from a suitable auditorium at their home institutions. 
  • The schedule of talks is unchanged.
  • There will be no conference fee.
  • Please stay updated via the website. 

We had very much hoped to be able to welcome you to Stavanger, since the Fysikermøte is as much a social as a scientific event.  Still, we feel that with our recently acquired common experience with digital dissemination, a virtual meeting is much, much better than nothing. Hopefully, we will be able to meet in person next time!

Fysikermøtet 2021

"Fysikermøtet" er et toårig møte med norske fysikere i akademia, industri, skoler og forskning.

Programmet består av plenumpresentasjoner om det siste innen fysikk i Norge, parallelle økter for de ulike gruppene i samfunnet, samt en dedikert populærvitenskapelig økt om energi. 

Programmet inkluderer også de tradisjonelle årsmøtene og prisutdelingen for Martin Landres-prisen for beste MSc-avhandling, den posterpris og utdanningspris.

Om NFS

Norsk Fysisk Selskap (NFS) ble offisielt grunnlagt i 1953, med formål å fremme forskning, opplysning og samarbeid på fysikkens områder. Selskapet hadde sitt utspring i Fysikkforeningen ved Universitetet i Oslo, som ble opprettet allerede i 1939. I dag har NFS rundt 1000 medlemmer. NFS er en medlemsorganisasjon i European Physical Society.

Selskapet har åtte faggrupper: Subatomær fysikk og astrofysikk, Kondenserte faser, med atomfysikk, Biofysikk, Optikk, Akustikk, Rom-, plasma- og klimafysikk, Industri- og energifysikk, og Undervisning og formidling (Norsk Fysikklærerforening). Siktemålet med gruppene er å styrke kontakten mellom medlemmer med samme interessefelt. Les mer om faggruppene.

I tillegg til faggruppene, har NFS opprettet nettverkene Nettverk for kvinner i fysikk og Nettverk for fysikkhistorie og filosofi.

Participants
  • Abhijit Bhat Kademane
  • Adam Takacs
  • Aksel Hiorth
  • Aleksi Kurkela
  • Alex Nielsen
  • Alexander Read
  • Alexander Rothkopf
  • Amanda Lavinia Kjærnsmo
  • Anders Kristoffersen
  • Anders Kvellestad
  • Anders Tranberg
  • Ann-Cecilie Larsen
  • Antoine Camper
  • Are Raklev
  • Arne Reitan
  • Asgeir Osland
  • Asle Sudbø
  • Audun Theodorsen
  • Bharat Ghimire
  • Bjarne Stugu
  • Chidozie Agu
  • Christine Ellingsen
  • Daniel Alvestad
  • Daria Kotova
  • David McNutt
  • Diana Quintero
  • Dieter Roehrich
  • DIVYARANI C G
  • Dorthea Gjestvang
  • Eirik Eik Svanes'
  • Eirik Rolland Enger
  • Eli Bæverfjord Rye
  • Elisaveta Malamova
  • Erik Adli
  • Erik Stensrud Marstein
  • Erlend Magnus Viggen
  • Ervin Thorn
  • Eva Rauls
  • Francesca Di Mare
  • Francesco Pogliano
  • Fride Vullum-Bruer
  • Gard Stadheim
  • Gaurang Parkar
  • Geir Helgesen
  • Gerhard Ungersback
  • Germano Nardini
  • Gert Kluge
  • Gregor Decristoforo
  • Hans Arnold Winther
  • Helena Kolesova
  • Helge Bøvik Larsen
  • Hilde Nesse Tyssøy
  • Håvard Helstrup
  • Héctor Daniel Zúñiga López
  • Ida Storehaug
  • Imisioluwa Adebiyi
  • Ingrid Mann
  • Ingrid McKibben Lofnes
  • Ionut-Cristian Arsene
  • Jahed Abedi
  • Joakim Bergli
  • Johann Stamm
  • Johannes Hamre Isaksen
  • John Veitch
  • Jon Andreas Støvneng
  • Jon Samseth
  • Jon-Are Sætre
  • Jonas El Gammal
  • Jonas Tjemsland
  • Juan Losada
  • Karanvir Singh
  • Karl Laundal
  • Kjartan Olafsson
  • Lasse Lorentz Braseth
  • Lisa Buschmann
  • Magdalena Eriksson
  • Magdalena Korzeniowska
  • Magnar Bjørås
  • Magnus Lilledahl
  • Magnus Rentsch Ersdal
  • Maria Markova
  • Marianne Bjørøen
  • Mehdi Belhaj
  • Michael Baziljevich
  • Oleg Komoltsev
  • Olena Zavorotynska
  • Paolo Marcoccia
  • Pascal Sado
  • Paul de Medeiros
  • Pawel Sikorski
  • Per Amund Amundsen
  • Per Osland
  • Pål Brekke
  • Pål-Store Storli
  • Ragnhild Aurlien
  • Rashmi Dahal
  • Rasmus Larsen
  • Renate Mauland-Hus
  • Richard Muller
  • Sajidah Ahmed
  • Sara Gasparini
  • Shiming Yuan
  • Sigbjørn Hervik
  • Simon Huiberts
  • Simon Walker
  • Spencer Hatch
  • Stian Hartman
  • Stian Ramsnes
  • sunniva siem
  • Sverre Holm
  • Tamas Tornyi
  • Thomas Klinger
  • Tina Knudsen
  • Tine Uberg Nærland
  • Tinna Gunnarsdottir
  • Tomas Brauner
  • Troels Schönfeldt
  • Trond Kvamsdal
  • Vegard Undheim
  • Viswanathan Lakshmi Narayanan
  • wanja paulsen
  • Wojciech Miloch
  • YILUN DU
  • Åshild Fredriksen
  • Øyvind Sande Borck
Fysikermøte 2021
    • 12:00 13:00
      Pause: Lunsj
    • 13:00 14:00
      Plenumforedrag: Åpning og Oversikt
      • 13:00
        Åpning 15m
        Speakers: Alexander Rothkopf (UiS TN IMF), Anders Tranberg (UiS - TN - IMF)
      • 13:15
        Oversikt presentasjon 45m
        Speaker: Prof. Asle Sudbø (NTNU)
    • 14:00 15:30
      Plenumforedrag: Faggrupper
      • 14:00
        Non-integer derivatives in acoustics and other areas of physics 30m
        Speaker: Prof. Sverre Holm (University of Oslo)
      • 14:30
        EISCAT_3D Radar for Upper Atmospheric and Near-Earth Space Research 30m

        EISCAT_3D is a multi-static phased array radar system for observations of the upper polar atmosphere and near-Earth space. It measures the incoherent scatter of electromagnetic waves by free electrons in the upper atmosphere, i.e. the ionosphere. The electrons couple to ions and charged dust through plasma oscillations and to the neutral particles through collisions. These couplings determine the frequency spectrum of the scattered waves. As a result, the incoherent scatter can be used to study a broad range of space plasma phenomena, including aurora. The electron densities, electron and ion temperatures, and ion vector velocities can be reliably derived from the observed spectra. These ionospheric parameters can be measured at heights ranging from at least 80 to 600 km to study the variable effects of solar and cosmic conditions on the ionosphere. In addition to the ionospheric incoherent scatter spectra, EISCAT_3D will measure and determine vertical and horizontal winds, static stability, parameters for atmospheric waves, atmospheric turbulence, atmospheric vorticity, meteor head echoes and trails, mesospheric dust properties and atmospheric layer boundaries. EISCAT_3D will be operational for users at the end of 2022 with the goal to study the upper polar atmosphere during at least two solar cycles. The measurements are important for studies related to understanding the physics of the upper atmosphere and its interaction with space, and for understanding the coupling between the different heights of the atmosphere and their influence on Earth’s climate. The measurements are relevant for understanding space weather, which comprises the variable effects of solar and cosmic conditions on the ionosphere and its effects on technologies on Earth, such as the accuracy of GPS tracking. The project will also carry out space debris observations to aid in tracking the many objects orbiting the Earth.

        EISCAT_3D is part of the international EISCAT Scientific Association that operates radar installations on Svalbard and on the Fenno-Scandinavian northern mainland. EISCAT is registered as a Swedish foundation and is currently funded by research councils and institutions in China, Finland, Japan, Norway, Sweden and the United Kingdom. EISCAT_3D is landmark project of ESFRI, the European Strategy Forum for Research Infrastructure. The EISCAT_3D Norway project is supported by researchers at UiT, UiB, UiO, NTNU, UNIS, Andøya Space Center and UiT as project coordinator. The Norwegian investment into EISCAT-3D is funded by Research Council of Norway Project 245683.

        Speaker: Prof. Mann Ingrid (Department of Physics and Technology, UiT the Arctic University of Norway)
      • 15:00
        Industri- og energifysikk 30m
        Speaker: Dr Erik Stensrud Marstein (IFE)
    • 15:30 16:00
      Pause: Kaffepause
    • 16:00 17:30
      Parallelle Foredrag: Block A II - Subatomic/Astro
      • 16:00
        Observation of a multimode quasi-normal spectrum from a perturbed black hole 20m

        When you hit a drum, it vibrates and emits a sound. When you hit a black hole, it also vibrates and emits gravitational waves. Hitting black holes is not very easy, but fortunately nature does it for us with black hole collisions. Remarkably, general relativity predicts that the vibration of a black hole is rather simple. The spectrum of vibrational modes depends only on the mass and angular momentum of the black hole. Thus if you can detect multiple vibrational modes of the black hole, you can test whether it really is a black hole according to general relativity. Here I will discuss prospects for detecting multiple modes from black holes using gravitational waves, both on the ground (LIGO) and in space (LISA).

        Speaker: Alex Nielsen
      • 16:20
        Analysis of the stellar origin black hole SGWB detected by LISA 20m

        We aim to estimate the Stochastic Gravitational Wave Background (SGWB), generated by a given stellar origin binary black hole (SOBBH) population, on the LISA strain.
        We start by simulating a SOBBH catalogue that will simulate as close as possible what the LISA detector would be able to observe at the time of launch, in order to do so, we implement the probability density functions (PDFs) of the last LIGO population inference paper (arxiv 2010.14533) with some small changing due to considerations based on intrinsic differences between the two types of missions.
        Given the SOBBH catalogue, we estimate the SNR of the sources by estimating their resulting strain on the detector and compare them with the Noise + SGWB curve, we will hence describe the predicted number of sources that would be resolvable and the resulting SGWB after a recursive subtraction of the resolvable sources for any given SNR threshold.
        We compare our prediction with the present-stage analytical estimations of the gravitational wave background.

        Speaker: Paolo Marcoccia (University of Stanvager)
      • 16:40
        Detecting inflationary gravitational waves with the LiteBIRD satellite 20m

        One of the next big steps in cosmology is the detection of inflationary gravitational waves from the Big Bang. These waves were created from the exponential expansion of the universe, just parts of a nanosecond after its birth. Signals from these ripples in space-time are extremely weak and have proved very hard to detect. One future telescope aiming to detect this signal is the JAXA’s LiteBIRD satellite, planned to be launched in the late 2020s to measure the Cosmic Microwave Background (CMB) for three years. In this talk I will give an overview of both the cosmology predicting these gravitational waves, and the LiteBIRD mission. I will also show some results from the data analysis algorithms developed at UiO to filter the CMB signal from the rest of the signal components.

        Speaker: Ragnhild Aurlien (Universitetet i Oslo)
      • 17:00
        Search for gravitational wave echoes in LIGO/Virgo data 20m

        Black Holes are possibly the most enigmatic objects in our Universe. From their detection in gravitational waves upon their mergers, to their snapshot eating at the centers of galaxies, black hole astrophysics has undergone an observational renaissance in the past 5 years. Nevertheless, they remain active playgrounds for strong gravity and quantum effects, where novel aspects of the elusive theory of quantum gravity may be hard at work. In this talk, I provide an overview of the strong motivations for why "Quantum Black Holes" may be radically different from their classical counterparts in Einstein's General Relativity. Then, I discuss and provide update on search for gravitational wave echoes as smoking guns for quantum black holes (or exotic compact objects) in LIGO/Virgo data, which have led to significant recent excitement and activity. I review the theoretical underpinning of gravitational wave echoes and critically examine the seemingly contradictory observational claims regarding their (non-)existence.

        Speaker: Jahed Abedi (University of Stavanger & AEI Hanover)
    • 16:00 17:30
      Parallelle Foredrag: Blokk A - Space/Plasma/Climate
      • 16:00
        Reconstruction of intermittent data time series by deconvolution 20m

        Intermittent fluctuations with large amplitudes compared to the background level can arise in far-from equilibrium and turbulent systems as well as due to sudden, large-amplitude forcing [1, 2]. Conditional averaging has been a much-used tool for finding amplitudes of intermittent events and the waiting time between them [2]. However, conditional averaging requires both significant amplitude thresholding and a large minimal distance between events, significantly limiting the number of found events. This reduces the accuracy of reconstructing intermittent data time series and the statistical analyses that can be derived.

        In this contribution, we study a variant of the Richardson-Lucy deconvolution algorithm [3, 4, 5]. This is an iterative method converging to a least squares solution which can be used to recover event amplitudes and arrival times from an intermittent time series for a known typical event shape. The method was applied to synthetically generated data time series consisting of a superposition of one-sided exponential pulses. Signal reconstruction and recovery of pulse amplitudes and arrivals is excellent for low to moderate overlap between events. As event overlap increases, signal recovery remains excellent, but an empirical threshold for reconstruction of amplitudes and arrival times is found. The sampling time must be 10 times lower than the average waiting time or less.

        For uncorrelated noise, the method requires no event thresholding and events separated by as little as two sampling times may be distinguished. In the presence of noise with the same correlation function as the signal, spurious events are observed, and some thresholding or filtering must be used to separate the noise from the data time series.

        Lastly, we demonstrate that the same method may be employed in recovering the typical event shape for known event amplitudes and arrival times. The event shape is reconstructed with good accuracy in the presence of noise and utilising different duration time distributions.

        References
        [1] R. Narasimha et. al., Phil. Trans. R. Soc. A (2007) 365, 841–858.
        [2] A. Theodorsen et. al., Plasma Phys. Contr. F. (2016) 58, 044006.
        [3] W. H. Richardson, J. Opt. Soc. Am. (1972) 62, 55-59.
        [4] L. B. Lucy, Astron. J. (1974) 79, 745.
        [5] F. Benvenuto et. al. Inverse Probl. (2009) 26, 025004.

        Speaker: Sajidah Ahmed (University of Tromsø)
      • 16:20
        Estimating temperature response to volcanic eruptions 20m

        In order to estimate the global temperature response and climate sensitivity to radiative forcing, volcanic activity is an important testbed. This work uses a non-parametric method for estimating the temperature response due to volcanic forcing from a simulation of the NorESM model [1]. In addition, this response will be convolved with reconstructed volcanic forcing and compared to temperature recordings. The volcanic forcing and the temperature response data sets are given in [2] and [3] and cover the last two millennia. Most previous attempts of acquiring the response function have been by use of parametric models and parameter fits based on historical data (e.g. [4] and [5]).

        Under the assumption that the temperature responds linearly to the forcing, the system is modelled using the filtered Poisson process (FPP) such that the Richardson-Lucy deconvolution algorithm can be applied. The FPP is a methodological model that describes a signal as superposed pulses. The sum of pulses can be written as a convolution as $T=G*F$, where $T$ is the temperature, $F$ is the forcing and $G$ is some response function. Using the Richardson-Lucy deconvolution algorithm we can get back $G$ given $F$ and $T$, that is, we get back the response from knowing the volcanic forcing and the temperature recording [6]–[8]. This approach is thus a non-parametric method of acquiring the response function, and because of the superposition of pulses it is also insensitive to pulse overlap.

        Further, the response function obtained may be used within the same framework to predict the temperature evolution when different forcing scenarios are run, for example a doubling of CO2 scenario. This is, of course, still assuming a linear dependence between the forcing and temperature response.

        References

        1. M. Bentsen et al., “The norwegian earth system model, noresm1-m – part 1: Description and basic evaluation of the physical climate,” Geoscientific Model Development, 2013, vol. 6, no. 3, pp. 687–720.
        2. P. D. Jones and M. E. Mann, “Climate over past millennia,” Reviews of Geophysics, 2004, vol. 42, no. 2, pp. 1–42.
        3. PAGES 2k Consortium. et al., “Consistent multidecadal variability in global temperature reconstructions and simulations over the common era,” Nature Geoscience, Aug. 2019, vol. 12, no. 8, pp. 643–649.
        4. G. J. Boer, M. Stowasser, and K. Hamilton, “Inferring climate sensitivity from volcanic events,” Climate Dynamics, Feb. 2007, vol. 28, no. 5, pp. 481–502.
        5. F. A. Bender, A. M. L. Ekman, and H. Rodhe, “Response to the eruption of Mount Pinatubo in relation to climate sensitivity in the CMIP3 models,” Climate dynamics, Oct. 2010, vol. 35, no. 5, pp. 875–886.
        6. W. H. Richardson, “Bayesian-Based Iterative Method of Image Restoration*,” J. Opt. Soc. Am., Jan. 1972, vol. 62, no. 1, pp. 55–59.
        7. L. B. Lucy, “An iterative technique for the rectification of observed distributions,” The Astronomical Journal, 1974, vol. 79, no. 6, p. 745.
        8. F. Benvenuto, R. Zanella, L. Zanni, and M. Bertero, “Nonnegative least-squares image deblurring: Improved gradient projection approaches,” Inverse Problems, 2010, vol. 26, no. 2.
        Speaker: Mr Eirik Enger (UiT)
      • 16:40
        Axial and radial development of the hot electron distribution from a helicon plasma source, measured by a retarding field energy analyzer (RFEA). 20m

        The information about the electron population emanating from a helicon source plasma is important in order to understand the formation of the current-free double layer (CFDL) between the source and the downstream region of a helicon plasma. The electrons need an energy higher than the potential drop across the CFDL to escape downstream from the source, and at these energies the signal of a standard Langmuir probe is less accurate.
        We present measurements of the high-energy tail of the electrons by an inverted RFEA. To reach the probe, these electrons must have energies above Vp, which can vary over the region of the measurement. By constructing a full distribution from the electron temperature Te obtained from the electron IV curve and the Vp obtained from the ion IV-curve from a standard RFEA setup, we obtained a density measure of the hot distribution independent of Vp. We investigate variation of the high-energy tail of the EEDF in the radial as well as axial directions, in the two different cases of a purely expanding magnetic field nozzle, and a more constricted one by applying current in a third, downstream coil. The derived densities and temperatures of electrons from the source are then compared to an analytic model of the downstream development of the electron density from the source.
        The method also allows for directional measurement of the electron current to the probe. This property is used in order to distinguish between the densities from the downstream and upstream direction.

        Speaker: Lisa Buschmann (UiO)
      • 17:00
        Finding an elephant in the aurora – Using machine learning to classify Northern lights images and predict phenomena 20m

        UiO has been operating all-sky imagers in the arctic regions for over 20 years. Between October and March images are taken at two different wavelengths every 5-30 seconds, resulting in a collection of almost 8 million images taken in Ny-Ålesund and Longyearbyen since 2006. These images are supplemented by magnetometer measurements, information about GNSS-signal quality of satellites in the field of view of the imager and ceilometer measurements giving the cloud base height near the imager.
        Using pre-trained neural networks, we extract numerical features from the images. These features are used to predict the type of phenomenon visible in the image and relate the image to its supplementary data.
        Preliminary results show good correlation between the prediction of cloudy images and data from the ceilometer, as well as good classification of aurora into arcs, diffuse or discrete aurora. On smaller timescales, relationships between the features and magnetometer data can also be established.

        Speaker: Pascal Sado
    • 09:00 10:00
      Plenumforedrag: Aktuelle Temaer I
      • 09:00
        LIGO 1h
        Speaker: Dr John Veitch (University of Glasgow)
    • 10:00 10:30
      Pause: Kaffepause
    • 10:30 12:30
      Plenumforedrag: Aktuelle Temaer II
      • 10:30
        LISA 1h
        Speaker: Germano Nardini (UiS)
      • 11:30
        To Mars with Norwegian technology on Perseverance 1h
        Speaker: Dr Pål Brekke (Norsk Romsenter)
    • 12:30 13:30
      Pause: Lunsj
    • 13:30 15:00
      Parallelle Foredrag: Blokk B - Subatomic/Astro
      • 13:30
        Hvorfor simulerer vi våre detektorer? 20m

        På CERN har LHC vårrengjøring, også kjent som "Long Shutdown 2".
        En periode dedikert til vedlikehold og oppgradering av maskiner, magneter og eksperimenter.
        ALICE eksperimentet oppgraderer flere av detektorene sine, og er snart klar for å slåes på for
        sitt tredje fysikk "turnus" som skal kjøre i tre år.
        Etter dette kommer "Long Shutdown 3" i 2025-2027, hvor minst en ny detektor skal stå klar til
        installasjon i eksperimentet. FoCal er navnet på denne, "Forward Calorimeter", som skal ta nye målinger
        ved lav vinkel i forhold til partikkelstrålene.
        Målet er å få data ved disse vinklene (høy "pseudorapidity") for å f.eks. studere parton-distribusjonsfunksjonen
        i hittil uutforskede regioner. For dette trenger vi å måle direkte fotoner og "jets".

        FoCal Består av 20 lag med detektorer og wolfram konverterings-lag. 18 av detektor-lagene bruken store silisiumdetektorer
        med veldig rask tidsoppløsning, men lav posisjons-oppløsning.
        De 2 resterende bruker pixel-sensorer med veldig høy posisjons-oppløsning, men tregere tidsoppløsning.
        Disse to lagene blir kalt "HG" lag, altså "High Granularity". Og disse simulerer jeg oppførselen til på UiB.

        I denne presentasjonen ønsker jeg å beskrive hvorfor vi ønsker simuleringer av detektorene vi skal bygge.
        Vi vil få føle på spørsmål som:
        - Hva er det som gjør at vi kan være sikre på at ting kommer til å virke?
        - I hvilken grad fungerer konseptene vi har brukt til å designe detektoren?
        - Hvordan må vi justere detektoren?
        - Hvilke usikkerheter er igjen etter vi er ferdige å simulere?

        Speaker: Magnus Rentsch Ersdal (University of Bergen (NO))
      • 13:50
        Charmonium production in pp collisions with ALICE 20m

        Studying the production of charmonium states in hadronic collisions may improve our understanding of the theory describing the strong interaction, known as quantum chromodynamics (QCD). The formation of heavy charm quark pairs takes place during the initial hard partonic scattering and can therefore be calculated using perturbative QCD, while the evolution into a colorless bound state is a non-perturbative process. The production mechanism is described by several theoretical approaches, among them the non-relativistic QCD (NRQCD) effective field theory. NRQCD calculations are capable of describing the measured production yields as a function of the transverse momentum but have difficulties in simultaneously describing the polarization, often referred to as the polarization puzzle. Recently, LHCb and CMS measured the fragmentation of J/psi (the lightest vector onium state in the charm sector) in jets. The measurements found the production of prompt J/psi mesons to be less isolated than predicted. The observed lack of isolation may be related to the polarization puzzle, and further charmonium measurements may help shed a light on our understanding of charmonium production.
        The ALICE detector is capable of measuring quarkonium states down to zero transverse momentum both at forward and midrapidity, measuring their decay through the dimuon and dielectron channel, respectively. In this contribution, recent quarkonium measurements in pp collisions will be discussed, with the main focus on the inclusive J/psi cross section measurement at center-of-mass energy 13 TeV. In addition, the future prospects of measuring J/psi in jets will be discussed.

        Speaker: Ingrid McKibben Lofnes (Universitetet i Bergen)
      • 14:10
        Beauty production through non-prompt J/Psi in pp and Pb-Pb collisions with ALICE 20m

        In hadronic collisions, heavy-flavour quarks (beauty and charm) are produced in hard-scattering processes with large momentum transfer. The production of hadrons containing beauty quarks provides a very important test of perturbative QCD calculations in pp collisions. Measurement of beauty-hadron production in heavy-ion collisions is a unique tool to investigate the properties of the colour-deconfined medium created, the quark--gluon plasma (QGP). Beauty quarks are effective probes of the QGP, as they are created via initial hard partonic scatterings and subsequently experience the full evolution of the QGP medium. In addition, beauty quarks, being four times heavier than charm quarks, can be exploited to study the mass dependence of the in-medium energy loss. Beauty production measurements in proton-nucleus collisions are useful to understand cold nuclear matter effects.

        In ALICE beauty production is investigated through different decay channels, one of them makes use of J/$\psi$ coming from the weak decays of beauty hadrons. The inclusive J/$\psi$ yield is composed of two contributions: prompt J/$\psi$ produced directly in the collision or indirectly via the decay of heavier charmonium states, and non-prompt J/$\psi$ originating from the decays of beauty hadrons. The latter are displaced from the main event vertex by an average distance of about 500 $\mu$m. Thanks to the excellent resolution on the reconstructed impact parameter (defined as the Distance of Closest Approach of the corresponding trajectory of the track to the primary vertex) provided by the Inner Tracking System,
        it is possible to measure such non-prompt J/$\psi$ fraction and disentangle the two contributions.

        In this presentation the beauty production measurements through the non-prompt J/$\psi$ decay channel in pp and Pb-Pb collisions measured by the ALICE collaboration at the LHC will be discussed.

        Speaker: Jon-Are Sætre (University of Bergen)
      • 14:30
        Reconstruction of B mesons with ALICE 20m

        At the ALICE experiment at CERN, quark-gluon plasma (QGP) is produced in the early stages of ultra-relativistic heavy ion collisions. Prior to the formation of QGP, heavy quarks and antiquarks (charm and beauty) are created in the initial hard scattering of the partons of the heavy ions. They subsequently move through the QGP, their numbers remaining conserved while they interact with the hot and dense medium. Thus, the QGP can be studied by comparing hadron spectra from heavy ion collisions to corresponding reference spectra from proton-proton collisions, where no QGP is expected. Such comparisons, at RHIC and LHC energies, show a suppression of most hadronic probes -- an observation that is interpreted as a signature of energy loss through interaction of the quarks with other free colour charges, and therefore indicative of QGP formation.

        Light quarks in hadronic probes can be produced later in the collision, but the heavy beauty quark is almost exclusively formed in the initial parton collisions. Beauty quarks thus experience the full history of the collision. The open beauty hadrons formed through combining with lighter quarks are likely to carry the kinematics of the beauty quark and reflect the beauty specific energy loss. Therefore the B meson ($b \bar{q}$, $\bar{b} q$, where $q$ is a light quark) is particularly well-suited as a probe to the QGP. However, the $B$ meson is difficult to study due to its many-prong decay topologies and the low production rate of the beauty quarks. In this talk I will present plans to use the $B \rightarrow J/\psi + K$ decay channel to probe the QGP, taking advantage of the low noise of the dilepton decay channel of $J/\psi$ and the analysis framework developed for this channel at the ALICE-Oslo group. The non-prompt $J/\psi$ mesons will have a displaced vertex with respect to the primary vertex. The upgrade of the Inner Tracking System of ALICE will improve the vertex determination capabilities and have a large impact on the precision of this measurement. This upgrade, combined with the increased statistics expected from LHC run 3, makes the reconstruction of B mesons as a probe to the QGP a feasible approach.

        Speaker: Ida Storehaug (University of Oslo)
    • 13:30 15:00
      Parallelle Foredrag: Blokk B II - Condensed matter
      • 13:30
        Magnetic transitions in an Inverse Vanadium Spinal oxide 20m

        Vanadium spinel oxides with formula $AV_2O_4$ (A = Fe, Co, etc.) have attracted much interest since they exhibit various intriguing physical properties, particularly in studying the role of orbital degrees of freedom in frustrated antiferromagnets [1,2]. However, very little attention has been paid to vanadium inverse spinel oxides $A_2VO_4$(A = Fe or Co). We report investigations on one of the inverse spinel oxides $Co_2VO_4$, where the spinal B-site has mixed occupancy by two distinct magnetic ions, $V^{4+}$ and low-spin $Co^{2+}$ . Our preliminary results show three distinct magnetic-phase transitions, among which a spontaneous magnetization reversal transition at 75 K, noncollinear and collinear magnetic transition at 140K and 168K, respectively. Here we report the results from polarized muon spectroscopy($\mu^+$SR) and thermodynamic characterizations, that have helped us in understanding unique physics of this complex system.

        [1] P.G. Radaelli, New J. Phys. 7, 53, (2005).
        [2]G. J. MacDougall et al. Phys. Rev. B 86, 060414(2012).

        Speaker: Abhijit Bhat Kademane (University of Stavanger,Norway.)
      • 13:50
        Bulk Properties Of One-Dimensional Magnetism in β-VOSO4 20m

        In this work the β phase of Vanadiumoxosulphate (VI) (β-VOSO4) crystal was used to study the physical properties of low dimensional magnetism in spin ½ chains.
        Structural analysis from X-ray diffraction and neutron diffraction performed on the sample, confirm that it crystallizes in the Pnma (62) space group. β-VOSO4 has V4+ bounded to six oxygen that gives it an octahedral configuration with one unpaired electron, thus with a total spin 1/2. The V-O-V bound running parallel to the a-axis form a spin ½ chain.
        The physical effect of this spin chain on the magnetic susceptibility and heat capacity was examined and it shows that the magnetic moment is isotropic and the intra-chain magnetic interaction is antiferromagnetic. This magnetic behavior has a significant effect on the susceptibility and heat capacity at temperatures below 60K. The magnitude of the magnetic exchange interaction between the spins was calculated to range from 45.4 K to 43.9K from fits to the magnetic susceptibility.

        Speaker: Mr Chidozie Agu (University of Stavanger (Student))
      • 14:10
        Applying the 'MaXrd' package in research on inclusion compounds 20m

        Inclusions of metallocenes into host frameworks of urea and thiourea have been studied widely for years due to their interesting structure and elusive arrangement of guest molecules.
        Since conventional structure solution procedures can only provide a time-averaged picture, an alternative «bottom-up» approach was proposed in which an imperfect crystal structure is built in Mathematica via the MaXrd package.
        Experimental diffraction patterns, which are rather complex, may be compared with simulations.
        In this presentation the process will be demonstrated with examples.

        Speaker: Mr Stian Ramsnes
      • 14:30
        Magnetic ordering in $SrTm_2O_4$: muon induced distortion effects 20m

        $SrTm_2O_4$ belongs to the family of $SrLn_2O_4$ (Ln - rare-earth ions), where many unconventional magnetic phenomena have been discovered [1]. However, $SrTm_2O_4$ does not show either long-range or short-range order down to 65mK[2].On the other hand, our muon spin rotation/relaxation (µSR) results show signs of spontaneous magnetic ordering even at near room temperatures with no sign of critical temperature. We conclude with our muon stopping site calculations(µ-DFT) and modeling the impact of muon-induced distortion on the crystal field levels that the quasi-static local field observed with the µSR is due to muon-induced distortions.

        [1] O. A. Petrenko, Low-Temperature Physics 40, 106 (2014).

        [2] Haifeng Li et.al. J. Mater. Chem. C3,7658 (2015).

        Speaker: Abhijit Bhat Kademane (University of Stavanger,Norway.)
    • 13:30 15:00
      Parallelle Foredrag: Blokk B III - Space/Plasma/Climate
      • 13:30
        The LOcal Mapping of Polar ionospheric Electrodynamics (LOMPE) approach to assimilation of regional ionospheric data 20m

        Much of what we know about large-scale variations in the solar wind-magnetosphere-ionosphere-thermosphere system comes from statistical analyses of average patterns and responses via observational data sets built up over long periods of time. With the advent in the past 10–20 years of large observational networks and consortia such as SuperDARN, SuperMAG, and the Iridium satellites, we are entering a new observational era in which it is possible to produce nearly instantaneous maps of some ionospheric parameters over large areas. In this presentation I outline a new assimilative approach for moving beyond the typical statistical analysis of steady-state averages by using these next-generation datasets to model regional ionospheric electrodynamics. I also present some preliminary validation results based on comparison with output from the GAMERA global geospace model.

        Speaker: Dr Spencer Hatch (Birkeland Centre for Space Science, Institutt for fysikk og teknologi, Universitetet i Bergen)
      • 13:50
        Electrojet estimates from mesospheric magnetic field measurements 20m

        The auroral electrojet is traditionally measured remotely with magnetometers on ground or in low Earth orbit (LEO). The sparse spatial coverage of measurements, combined with a vertical distance (~100 km to ground and typically >300 km to LEO satellites) means that smaller scale sizes cannot be detected. Because of this, our understanding of the spatiotemporal characteristics of the electrojet is incomplete. Recent advances in measurement technology allow us to overcome these limitations by multi-point remote detections of the magnetic field in the mesosphere, very close to the electrojet. We present a theoretical prediction of the magnitude of these disturbances, inferred from the spatiotemporal characteristics of magnetic field-aligned currents. We further discuss how the Electrojet Zeeman Imaging Explorer (EZIE) satellites that will carry Zeeman magnetic field sensors will be used to essentially image the equivalent current at unprecedented spatial resolution. The electrojet imaging is demonstrated by combining carefully simulated measurements with a spherical elementary current representation using a novel inversion scheme. This new capability will allow us to finally resolve long-standing controversies such as – what is the substorm current wedge configuration?

        Speaker: Karl Laundal (University in Bergen)
      • 14:10
        Simulation of near-solar dust trajectories influenced by mass loss 20m

        We investigate the effect of destruction processes of cosmic dust particles on their propagation near the Sun. This work is motivated by on-going observations of two spacecraft which explore the inner solar system and the vicinity of the Sun: the NASA Parker Solar Probe (PSP) and ESAs Solar Orbiter (SolO). SolO makes observations of the Sun and in-situ measurements from elliptic orbits which are ultimately going to approach as close as ~60 solar radii (~0.285 AU) to the Sun. PSP moves in elliptic orbits closer to the Sun inward to ~10 solar radii. PSP reaches within the ecliptic plane distances close to the Sun that have not been measured in-situ before. Both spacecraft can detect impacts of the cosmic dust particles, which are one of the major constituents of the interplanetary medium surrounding the Sun. The dust particles are destroyed by sputtering, fragmentation, and sublimation and near the Sun these processes become particularly important. We present model calculations of the dust trajectories in the vicinity of the Sun. The equation of motion is solved including gravity, radiation pressure force and Lorentz force. The Lorentz force is calculated assuming a Parker model of the magnetic field. The mass loss rate will be calculated along the trajectories based on mass loss rates for sublimation and solar wind sputtering. We discuss the results in the context of observational results from PSP and SolO.

        Speaker: Ingrid Mann (UiT, Actic University of Norway)
      • 14:30
        Neutral winds and electric fields with EISCAT 3D 20m

        Using incoherent scatter radar (ISR) to determine the neutral wind velocity in the ionosphere has been done for nearly 50 years. The method for finding the velocity of the neutral wind uses the ion velocity which is one of the parameters that the ISRs measure. The ion velocity is connected to the neutral wind velocity through collisions, and to electrical field through the Lorentz force where neither of these are directly known. However, at high altitudes, the ion motion is mostly dominated by the Lorentz force. When assuming that the electrical field is constant along the magnetic field lines, the neutral wind in the E region can be found. This procedure was first described by Brekke et al. [1973], and has been used and improved since [see Heinselman and Nicolls 2008, Nygrén (2011), and references therein].

        One of the advancements of the upcoming ISR EISCAT 3D (E3D) is that it will be able to measure three components of the ion velocity simultaneously at all ranges [McCrea et al. 2015]. We estimate the ISR spectrum and its uncertainty to find the accuracy of ion velocity measurements of E3D. We find that it is strongly dependent on the electron density.
        In reality, the electrical field might vary over height. If letting it do so, the underdetermined nature of the problem is revealed. By using other constraints, one can show that it is possible to obtain estimates of the electrical field in the upper E region as well.

        References:
        Asgeir Brekke, Joe R. Doupnik, and Peter M. Banks (1973): “A Preliminary Study of the Neutral Wind in the Auroral E Region”. In: Journal of Geophysical Research 78.34 (1973), pp. 8235–8250.

        Craig J. Heinselman and Michael J. Nicolls (2008): “A Bayesian approach to electric field and E-region neutral wind estimation with the Poker Flat Advanced Modular Incoherent Scatter Radar”. In: Radio science 43.RS5013 (2008).

        Ian McCrea, Anita Aikio, Lucilla Alfonsi, Evgenia Belova, Stephan Buchert, Mark Clilverd, Norbert Engler, Björn Gustavsson, et al. (2015): “The science case for the EISCAT_3D radar”. In: Progress in Earth and Planetary Science 2.21. DOI : 10.1186/s40645-015-0051-8.

        Tuomo Nygrén, Anita T. Aikio, Ritva Kuula, and Mirela Voiculescu (2011): “Electric fields and neutral winds from monostatic incoherent scatter measurements by means of stochastic inversion”. In: Journal of Geophysical Research 116.A05305 (2011). DOI: 10.1029/2010JA016347.

        Speaker: Johann Stamm (UiT)
    • 15:00 15:30
      Pause: Kaffepause
    • 15:30 17:10
      Parallelle Foredrag: Blokk C - Subatomic/Astro
      • 15:30
        Test of the Brink-Axel Hypothesis in the Energy Region of the Pygmy Dipole Resonance in Sn Isotopes 20m

        The validity of the Brink-Axel hypothesis, which is especially important for numerous astrophysical calculations, is addressed for $^{116,120,124}$Sn below the neutron separation energy by means of three independent experimental methods. The $\gamma$-ray strength functions (GSFs) extracted from primary $\gamma$-decay spectra following charged-particle reactions with the Oslo method and with the Shape method demonstrate excellent agreement with those deduced from forward-angle inelastic proton scattering at relativistic beam energies. In addition, the GSFs are shown to be independent of excitation energies and spins of the initial and final states.
        The results provide the most comprehensive test of the generalized Brink-Axel hypothesis in heavy nuclei so far, demonstrating its applicability in the energy region of the pygmy dipole resonance.

        Speaker: Mrs Maria Markova (University of Oslo)
      • 15:50
        Indirect measurements of neutron capture rates for astrophysical i-process 20m

        n/t

        Speaker: Francesco Pogliano (University of Oslo)
      • 16:10
        Measuring nuclear properties of 187-188Re 20m

        n/t

        Speaker: Marianne Bjørøen (Univerisyt of Oslo)
      • 16:30
        Deep learning jet modifications in heavy-ion collisions 20m

        Jet interactions in a hot QCD medium created in heavy-ion collisions are conventionally assessed by measuring the modification of the distributions of jet observables with respect to the proton-proton baseline. However, the steeply falling production spectrum introduces a strong bias toward small energy losses that obfuscates a direct interpretation of the impact of medium effects in the measured jet ensemble. In this talk, we will explore the power of deep learning techniques to tackle this issue on a jet-by-jet basis.

        Toward this goal, we employ a convolutional neural network (CNN) to diagnose such modifications from jet images where the training and validation is performed using the hybrid strong/weak coupling model. By analyzing measured jets in heavy-ion collisions, we extract the original jet transverse momentum, i.e., the transverse momentum of an identical jet that did not pass through a medium, in terms of an energy loss ratio. Despite many sources of fluctuations, we achieve good performance and put emphasis on the interpretability of our results. We observe that the angular distribution of soft particles in the jet cone and their relative contribution to the total jet energy contain significant discriminating power, which can be exploited to tailor observables that provide a good estimate of the energy loss ratio.

        With a well-predicted energy loss ratio, we study a set of jet observables to estimate their sensitivity to bias effects and reveal their medium modifications when compared to a more equivalent jet population, i.e., a set of jets with similar initial energy. Then, we show how this new technique provides unique access to the initial configuration of jets over the transverse plane of the nuclear collision, both with respect to their production point and initial orientation. Finally, we demonstrate the capability of our new method to locate with unprecedented precision the production point of a dijet pair in the nuclear overlap region, in what constitutes an important step forward towards the long term quest of using jets as tomographic probes of the quark-gluon plasma.

        [1] Yi-Lun Du, Daniel Pablos, Konrad Tywoniuk, Deep learning jet modifications in heavy-ion collisions, arXiv:2012.07797 [hep-ph], JHEP. 2021, 206 (2021)

        Speaker: Dr YILUN DU (University of Bergen)
      • 16:50
        Årsmøte Subatomær fysikk og astrofysikk 20m

        n/t

    • 15:30 17:10
      Parallelle Foredrag: Blokk C II - Space/Plasma/Climate
      • 15:30
        Numerical simulations of plasma turbulence in the boundary of fusion experiments 20m

        Heat exhaust in the boundary region of fusion experiments remains to this day the biggest challenge towards harvesting fusion power. Transport of particles and heat in this region is dominated by radial motion of coherent structures known as blobs [1].
        Long time series obtained by fixed point probe measurements in recent experiments reveal highly intermittent fluctuations in the ion saturation current. These measurements are well described by a super-position of uncorrelated exponential pulses with exponential decay and exponentially distributed pulse amplitudes [2; 3; 4]. In previous numerical simulations of boundary plasma turbulence the statistical properties of plasma fluctuations were investigated [5; 6; 7]. In order to validate this modeling approach we run simulations in the boundary turbulence code BOUT++ [8; 9] to obtain long time series that can be compared to time series obtained from experimental measurements. These simulations use a two dimensional fluid model describing the evolution of the plasma density and vorticity in the two dimensional plane perpendicular to the magnetic field.
        We find that the radial particle density profile is exponential with a radially constant scale length. The probability density function for the particle density fluctuations has an exponential tail. Radial motion of blob-like structures leads to large-amplitude bursts with an exponential distribution of peak amplitudes and the waiting times between them. The fluctuation statistics obtained from the numerical simulations are in excellent agreement with recent experimental measurements from magnetically confined plasmas.

        References
        [1] D. A. D’Ippolito, et. al., Phys. Plasmas, 18, 060501 (2011).
        [2] A. Theodorsen, et. al., Plasma Phys. Contr. Fusion, 58, 044006, (2016). [3] R. Kube, et. al., Plasma Phys. Contr. Fusion, 60, 065002, (2018).
        [4] O. E. Garcia, et. al., Nucl. Mater. Energy, 12, 36-43 (2017).
        [5] Y. Sarazin, et. al., J. Nuclear Mater., 313, 796-803, (2003).
        [6] N. Bisai, et. al., Phys. Plasmas, 12, 072520, (2005).
        [7] O. E. Garcia, et. al., Phys. Plasmas, 12, 062309, (2005).
        [8] B. D. Dudson, et. al., Comp. Phys. Commun., 180, 1467-1480, (2009). [9] F. Militello, et. al., Plasma Phys. Contr. Fusion, 59, 125013, (2017).

        Speaker: Gregor Decristoforo (UiT)
      • 15:50
        Estimation of stochastic model parameters on single point and two point time series 20m

        The boundary of magnetically confined plasmas is in a strongly fluctuating state due to the propagation of large amplitude coherent structures. A stochastic single-point model based on the superposition of un-correlated pulses has been successfully validated across different reactors. We extend this model to describe two-point measurements. This model can describe experimental techniques such as gas puff imaging which are routinely performed in reactor shots. Within this framework, we develop methods to estimate model parameters, such as the pulse duration, asymmetry and distribution of delays. These methods can be used to obtain accurate estimations of the velocity of propagating structures. Methods traditionally used in the literature are based on maximizing the cross-correlation or the cross-conditional average. Using synthetic data, we compare our estimates with those obtained with traditional methods and show that our method is significantly less biased and can be used to obtain higher-order moments of the delays.

        Speaker: Juan Losada
      • 16:10
        Current understanding of mesospheric bores – characteristics, effects and observational challenges 20m

        Mesospheric bores are non-linear solitary type internal waves observed in the 80 – 100 km region of Earth atmosphere, the upper mesosphere. The existence of these waves is known for more than two decades. Researchers have attained a reasonable understanding on the nature of such waves. However, some of the observed characteristics of these waves cannot be explained based on existing knowledge. Mesospheric bores were initially thought to be very rare events, but recent investigations indicate that such events are relatively frequent. These waves have potential to contribute considerably to the energy and momentum deposition within the mesosphere since they propagate long horizontal distances and are associated with large amplitude gravity waves. Moreover, their effects on the surrounding atmosphere are not understood. Recent results show that they play a role in altering the concentrations of minor species in the upper mesosphere within short time scales. We would like to provide a brief overview of our current understanding of the mesospheric bores, highlight the recent observations of their effects on the sodium layer and the noctilucent clouds with emphasis on observations from the Northern Scandinavia, and also discuss the challenges in the observational studies of the mesospheric bores.

        Speaker: Viswanathan Lakshmi Narayanan (UiT The Arctic University of Norway)
      • 16:30
        Turbulent signatures in the Auroral Cusp Ionosphere based on sounding rocket observations 20m

        Space plasmas display fluctuations and nonlinear behavior at a broad range of scales, being in most cases in a turbulent state. The majority of these plasmas are also considered to be heated, with dissipation of turbulence as a possible explanation. Despite of many studies and advances in research, many aspects of the turbulence, heating and their interaction with several space plasma phenomena (e.g., shocks, reconnection, instabilities, waves), remain to be fully understood and many questions are still open.
        Plasma irregularities and turbulence are believed common in the F-region ionosphere and because of their impact on the GNSS and the human activity [1, 2, 3] in the polar regions, a detailed understanding is required.
        This study provides a characterization of the turbulence developed inside the polar-cusp ionosphere, including features as intermittency, not extensively addressed so far.
        The electron density of ICI-2 and ICI-3 missions have been analyzed using advanced time-series analysis techniques and a standard diagnostics for intermittent turbulence. The following parameters have been obtained: the autocorrelation function, that gives useful information about the correlation scale of the field [4]; the energy power spectra, which show the average spectral indexes ∼ −1.7, not far from the Kolmogorov value observed at MHD scales [5], while a steeper power law is suggested below kinetic scales [6]. In addition, the PDFs of the scale-dependent increments display a typical deviation from Gaussian that increase towards small scales due to intense field fluctuations, indication of the presence of intermittency and coherent structures [7, 8, 9]. Finally, the kurtosis-scaling exponent [10, 11] reveals an efficient intermittency, usually related to the occurrence of structures.

        References
        [1] V. Bothmer, and I. A. Daglis, “Space Weather: Physics and Effects”, 2007, Springer, New York.
        [2] H. C. Carlson, 2012, “Sharpening our thinking about polar cap ionospheric patch morphology, research, and mitigation techniques”, Radio Sci., 47, RS0L21.
        [3] J. I. Moen, H. C. Carlson, S. E. Milan, N. Shumilov, B. Lybekk, P.E. Sandholt,, and M. Lester, “Space weather
        challenges of the polar cap ionosphere”, J. Space Weather Space Clim., 2000, 3(A02), 13.
        [4] S. Pope, Turbulent Flows, Cambridge University Press, 2000, Cambridge.
        [5] R. J. Leamon, C. W. Smith, N. F. Ness, W. H. Matthaeus, “Observational constraints on the dynamics of the
        interplanetary magnetic field dissipation range”, J. of Geophys. Res., 1998, 103(A3), 4775-4787.
        [6] A. Spicher, W. J. Miloch, and J. I. Moen, “Direct evidence of double-slope power spectra in the highlatitude ionospheric plasma”, Geophys. Res. Lett., 2014, 41, 1406–1412.
        [7] U. Frisch, “Turbulence. The Legacy of A. N. Kolmogorov”, Cambridge University Press, 1995, Cambridge.
        [8] K. R. Sreenivasan, “Fluid Turbulence”, Rev. Mod. Phys., 1999, Vol. 71, 2.
        [9] R. Bruno, and V. Carbone, “The Solar Wind as a Turbulence Laboratory”, Living Rev. Sol. Phys., 2005, 10, 2.
        [10] F. Anselmet, Y. Gagne, E. J. Hopfinger, and R. A. Antonia,“High order velocity structure functions in turbulent shear flows”, J. Fluid Mech., 1984, 140, 25, 63-89.
        [11] K. R. Sreenivasan, and R. Antonia, Ann. Rev. Fluid Mech., 1997, 29, 435-472.

        Keywords: Sounding rocket observations, Turbulence, Ionospheric Irregularities

        Speaker: Dr Francesca Di Mare (University of Oslo)
    • 09:00 09:15
      Vitenskap av Energi: Åpning
    • 09:15 10:00
      Vitenskap av Energi: Energi Oversikt
      Convener: Prof. Richard Muller (University of California, Berkeley)
    • 10:00 10:30
      Pause: Kaffepause
    • 10:30 12:00
      Vitenskap av Energi: Plenarsamtaler
      • 10:30
        Olje 30m
        Speaker: Aksel Hiorth (UiS - IOR)
      • 11:00
        Fisjon 30m
        Speaker: Alexander Rothkopf (UiS TN IMF)
      • 11:30
        Solenergi 30m
        Speaker: Dr Tine Uberg Nærland (IFE)
    • 12:00 13:00
      Pause: Lunsj
    • 13:00 15:30
      Vitenskap av Energi: Plenumssamtaler
      • 13:00
        Vannkraft 30m
        Speaker: Pål-Store Storli (NTNU)
      • 13:30
        Fusjon 30m
        Speaker: Prof. Thomas Klinger (Max-Planck-Institute for Plasma Physics)
      • 14:00
        Vindkraft 30m
        Speaker: Prof. Trond Kvamsdal (NTNU)
      • 14:30
        Hydrogen 30m
        Speaker: Olena Zavorotynska (UiS)
      • 15:00
        Batterier 30m
        Speaker: Dr Fride Vullum-Bruer (SINTEF)
    • 15:30 16:00
      Pause: Kaffepause
    • 16:00 17:50
      Parallelle Foredrag: Blokk D - Space/Plasma/Climate
      • 16:00
        NOx - the chemical fingerprint of the aurora 20m

        The energy transfer from the solar wind to the Earths magnetosphere fuels the Energetic Particle Precipitation (EPP). EPP refers to highly energetic electrons and protons that are accelerated into the atmosphere, mainly in the polar regions. This energetic particles influence the atmospheric chemical composition by producing nitric oxides(NOx) and hydrogen oxides (HOx), among others, which both are associated with an ozone(O3) loss.

        Auroral electrons(<30 keV) can penetrate to altitudes around the mesopause, where it will produce NOx, which are quite long-lived during polar winter and can be transported down into the lower mesosphere and stratosphere, where it will effectively destroy ozone.

        The medium energy electrons(MEE), with higher energies (30 keV–1000 keV), can penetrate further down into the atmosphere, reaching the lower mesosphere, and increasing the levels of NOx and HOx, which will result in mesospheric and stratospheric ozone loss.

        Including MEE into our current climate models will lead to more ozone depletion, which will cause an effective change in temperature in the mesosphere and stratosphere, resulting in a change on the zonal winds, i.e., a change in the dynamics of the atmosphere?

        Speaker: Mr Héctor Daniel Zúñiga López (University of Bergen)
      • 16:40
        Auroral oval boundary estimates from ground magnetometer measurements 20m

        By utilising measurements from twenty ground magnetometer stations in Fennoscandia, divergence-free ionospheric currents above this region are modelled using spherical elementary currents (SECS). New modelling techniques are implemented that coerce the model to find a solution that resembles the resolvable ionospheric currents. The divergence-free currents are evaluated along the $105^\circ$ magnetic meridian covering a period of almost 20 years with a resolution of 1 minute, as a result of the magnetometers chosen. From these sheet current density latitude profiles, the boundaries of the auroral electrojet are identified. After performing a large statistical analysis it is found that there is a significant IMF $B_y$ effect on the poleward boundary of the electrojets during the Summer but not during the Winter. We suggest that this seasonal effect can be attributed to the effects of lobe reconnection on the extent of currents in the auroral electrojets. Further work is done to compare the SECS derived electrojet boundaries with particle precipitation data from low orbit satellites.

        Speaker: Mr Simon Walker (University of Bergen)
      • 17:00
        Comprehensive analysis of scintillations over the Troll station using the all-sky camera and GNSS receiver 20m

        In this study, we use the first data from the all-sky camera installed in Antarctica at the Norwegian Research Station Troll. The auroral all-sky camera calibration was calibrated. Together with the ground-based TEC and scintillation receiver located there, a comprehensive analysis of the reasons for observing scintillations over the Troll station during the period of geomagnetic disturbances was carried out.

        Speaker: Daria Kotova (Department of Physics, University of Oslo)
    • 16:00 17:50
      Parallelle Foredrag: Blokk D II - Subatomic/Astro
      • 16:00
        Pandemic dark matter 20m

        We recently proposed a novel thermal production mechanism for dark matter based on the idea that dark matter particles $\chi$ can transform (`infect') heat bath particles $\psi$: $\chi \psi \rightarrow \chi \chi$. For a small initial abundance of $\chi$ this induces an exponential growth in the dark matter number density, closely resembling the epidemic curves of a spreading pathogen after an initial outbreak. In this talk, I will explain the main idea behind pandemic dark matter, focussing on the observation that it is indeed a rather natural extension to the more commonly studied freeze-in and freeze-out production mechanisms of dark matter.

        Speaker: Torsten Bringmann (University of Oslo)
      • 16:20
        Global fits beyond the "standard models" 20m

        GAMBIT is an open-source framework for performing large-scale statistical analyses of new theories in particle physics. In this talk I will introduce the GAMBIT Universal Model Machine (GUM), which is a new tool for automatically generating model-specific collider, dark matter, decay and spectrum code for GAMBIT, starting from the Lagrangian-level definition of a new theory. This new development marks a significant step towards a truly general toolchain for testing new theories against all available experimental results.

        Speaker: Anders Kvellestad (University of Oslo)
      • 16:40
        Quantum Field Theory and Geometry 20m

        I will explain how in modern mathematical physics tools of Geometry can be used to inform about Quantum Field Theory and vice versa. This can particularly be useful in the realm of strongly coupled field theories, although usually with some level of supersymmetry assumed.

        Speaker: Eirik Eik Svanes' (University of Stavanger)
    • 09:00 10:30
      Plenumforedrag: Faggrupper
      • 09:00
        Kondenserte fasers fysikk og atomfysikk 30m
        Speaker: Diana Quintero (UiS)
      • 09:30
        Biofysikk 30m zoom

        zoom

        Speaker: Prof. Magnar Bjørås (NTNU)
      • 10:00
        Subatomær fysikk og astrofysikk 30m
        Speaker: Ann-Cecilie Larsen (University of Oslo, Norway)
    • 10:30 10:50
      Pause: Kaffepause
    • 10:50 12:20
      Plenumforedrag: NFS Årsmøte & Priser
      • 10:50
        NFS Årsmøtet 1h 10m
        Speaker: Prof. Asle Sudbø (NTNU)
      • 12:00
        Priser 20m

        Martin Landrøs pris

        NFS Undervisningspris

        Speakers: Prof. Asle Sudbø (NTNU), Anders Tranberg (UiS - TN - IMF), Alexander Rothkopf (UiS TN IMF)
    • 12:20 12:35
      Plenumforedrag: Avslutning
      • 12:20
        Avslutning 15m
        Speakers: Anders Tranberg (UiS - TN - IMF), Alexander Rothkopf (UiS TN IMF)