Partikeldagarna 2017 (Stockholm)

6 Nov 2017, 09:30 → 7 Nov 2017, 17:00 Europe/Stockholm

DeGeersalen (Geovetenskapens hus)

Partikeldagarna will take place in Stockholm on November 6-7, 2017. The event is being organised by Stockholm University.

more information partikeldagarna2017.pdf

Monday, 6 November

09:30 → 10:15 Registration and coffee

10:15 → 12:45 Monday morning session

10:15 Welcome and practical info

Speakers: Chad Finley (Stockholm University), Sara Strandberg (Stockholm University)

Slides Welcome.pdf

10:30 Results from the 2016 flight of the PoGO+ hard X-ray polarimeter

PoGO+ is a balloon-borne telescope studying the polarization of hard X-ray emission from the Crab (pulsar and nebula) and Cygnus X-1 (an X-ray binary system). A successful one-week flight was conducted during the summer of 2016, launching from the Esrange Space Center, Sweden, and landing on Victoria Island, Canada. Observations of the two scientific targets were conducted on each day of the flight, with peak altitudes in the excess of 40 km, and with a pointing stability well within the 0.1 degree design requirement. PoGO+ is a successor to the PoGOLite Pathfinder, which conducted its maiden flight in 2013. Following a successful recovery of the payload, the scientific flight data has been analyzed, providing polarimetric parameters (polarization fraction and polarization angle) for the Crab system and Cygnus X-1. This presentation will briefly describe the PoGO+ instrument and the 2016 flight, along with observational results mainly for the Crab studies. An outlook to the expected results for the Cygnus X-1 measurements will also be provided.

Speaker: Dr Mette Friis (KTH)

Slides partikeldagarna.pdf

10:45 SPHiNX - a satellite-based GRB polarimeter

The study of gamma ray bursts (GRBs) has taken significant strides since GRBs were first reported by the Vela satellite mission in the 1970s. The Fermi and Swift satellite missions have enabled prompt localisation (imaging), high time resolution lightcurves (timing) and wideband spectral (spectroscopy) studies of the GRB. Despite the advances made in imaging, timing and spectroscopic studies, a number of questions concerning the emission mechanisms of the GRBs remain unanswered. A study of the polarisation signatures of different GRBs promises to answer some of these open questions. ​ The Satellite Polarimeter for High eNergy X-rays (SPHiNX) is a high energy polarimeter proposed to SNSB as the second Innosat mission. This is a dedicated satellite mission for monitoring and studying GRB polarisation signatures. This talk will give an overview of the design principles and working strategy of SPHiNX. Results from Geant4 based Monte-Carlo simulation studies of the polarimeter design will also be presented. The simulations demonstrate the ability of SPHiNX to detect polarisation (in the presence of high energy photon and charged particle backgrounds) and make use of these detections to understand the emission mechanism behind different GRBs. This talk will present the simulation methods, obtained results and resulting scientific interpretations from the SPHiNX mission in detail.

Speaker: Nirmal Kumar Iyer (KTH)

Slides SPHiNX.pdf

11:00 ALTO: A new wide field-of-view gamma-ray observatory in the Southern Hemisphere

ALTO is a wide field-of-view air shower detector array proposed for very-high-energy gamma-ray astronomy in the Southern Hemisphere. It will be a hybrid detector array consisting of around a thousand detector units (each unit comprises of a water Cherenkov detector and a scintillation detector) which will detect air showers induced by very-high-energy gamma rays (above ~200 GeV) in the Earth’s atmosphere. It is designed to attain a lower energy threshold, better angular resolution and improved sensitivity with respect to the existing HAWC experiment in Mexico. In this contribution, I will discuss the various science goals of ALTO, the design study and expected performance of the array based on Monte-Carlo simulations, and present a prototype array that is currently being developed in the campus of Linnaeus University as well as future plans of the project.

Speaker: Dr Satyendra Thoudam (Linnaeus University)

Slides partikeldagarna2017.pdf

11:15 IceCube: Exploring the Universe with neutrinos

The IceCube experiment is a cubic-kilometer-scale neutrino observatory that uses photosensors embedded in the ice near the South Pole. IceCube was built primarily to search for astrophysical neutrinos originating from some of the most energetic processes in the Universe. In 2013, IceCube conclusively showed the detection of astrophysical neutrinos, however the hunt for a specific source of neutrino emission has proved elusive. In this talk, I will discuss our recent efforts to identify sources of astrophysical neutrinos, including the recent search for neutrinos in coincidence with the binary neutron star merger detected by LIGO.

Speaker: Erin O'Sullivan (Stockholm University)

Slides Partikeldagarna2017_eosullivan.pdf

11:30 The physics case of the proposed large Water Cherenkov Detector GRIPnu

Searching for a difference between neutrino and anti-neutrino oscillations may open the way towards new fundamental physics and an explanation of why the world is made of only matter and no anti-matter. To discover such a difference, the development of a very large neutrino detector and a uniquely high-intensity neutrino beam is needed. The same detector will make possible investigations of cross-disciplinary phenomena like the energy generating processes in the Sun, the mechanism of Supernovae explosions and the radiogenic heating in the Earth's interior. The planned location of the neutrino detector, called GRIPnu, is in the Garpenberg mine in Dalarna. Physicists from Sweden, France, Turkey, Spain, Greece, Italy, Croatia, Bulgaria, Poland, Switzerland and United Kingdom participate in the EU H2020-supported Design Study of this neutrino research infrastructure. The presentation will give an overview of the physics case of the GRIPnu neutrino detector.

Speaker: Prof. Tord Ekelöf (Uppsala universitet)

Slides Ekelof_ESSnuSB_Partikeldagarna_6_Nov_2017.pdf

11:45 Invited speaker Frank Wilczek

12:45 → 13:45 Lunch

13:45 → 15:15 Monday afternoon session 1

13:45 Neutrinos from the Fermi Bubbles and the Galactic Center?

The Fermi Bubbles are extended regions of hard gamma-ray emission which were discovered with Fermi-LAT data to exist above and below the Galactic Center. In order to explain the origin of the gamma-rays, different theories are proposed. In particular, within hadronic models, highly-accelerated cosmic rays interact with interstellar matter and create the observed gamma-rays and in addition neutrinos. Besides the investigation of the Fermi Bubbles, the search for neutrinos was extended for the Galactic Center. An analysis method and the preliminary results of the study of a possible neutrino flux from the Fermi Bubbles and the Galactic Center, using data from the neutrino detector IceCube will be described in this presentation.

Speaker: Elisabeth Unger (Uppsala Universiy)

Slides 20171106_Partikeldagarna_FermiBubbles_EUnger_v2.pdf

14:00 Neutrinos from cosmic ray interactions in the Sun

Solar atmospheric neutrinos are produced in the high energy cascades that follow cosmic ray interactions with the outer parts of the Sun. We perform an updated calculation of the solar atmospheric neutrino flux and discuss the impact on searches for neutrinos from annihilations of weakly interacting massive particles (WIMPs). Our code is event-based and publicly available, and thus suitable for experiments. We find that about 2-3 solar atmospheric neutrino events per year are expected in an IceCube-like detector, generally higher than the Earth atmospheric neutrino flux per solid angle. The solar atmospheric neutrino flux can furthermore, although small, be a difficult background for solar WIMP searches as spectral differences can be challenging to distinguish with current neutrino telescopes.

Speaker: Carl Niblaeus (Stockholm University & the Oskar Klein Centre)

Slides Partikeldagarna-CarlNiblaeus.pdf

14:15 Thermalization time scales for WIMP capture by the Sun and the Role of Self-Interaction

In the process of dark matter capture by the Sun, Weakly Interacting Massive Particles (WIMPs) from the galactic halo can scatter against atomic nuclei in the solar interior, settle to thermal equilibrium with the solar core and annihilate to produce an observable flux of neutrinos. When studying this process, the time it takes for a gravitationally bound WIMP to reach thermal equilibrium is commonly neglected. I explore the thermalization process and find that the assumption of instantaneous thermalization breaks down only for some fine-tuned cases. I also present results showing that self-interaction between WIMPs can significantly amplify the capture rate and neutrino signal, within current limits to the WIMP self-interaction cross section.

Speaker: Mr Axel Widmark (Stockholm University)

Slides pres_partikeldagarna_WIDMARK.pdf

14:30 A Search for Magnetic Monopoles using the IceCube Neutrino Observatory

Magnetic monopoles are allowed in most extensions of the standard model. They are allowed in a wide range of masses, of which a large part lies outside of the reach of modern colliders. Therefore, in order to investigate the high mass range of magnetic monopoles we must search for monopoles produced in higher energy environments, such as the early Universe. According to Dirac’s quantization condition, a magnetic monopole would have a large effective charge compared to the elementary electric charge. This high effective charge would make magnetic monopoles into very bright Cherenkov radiation producers when traversing a dielectric medium, which in turn gives them a clear signature to distinguish from other events. In this talk I will present an ongoing search for a flux of magnetic monopoles using the IceCube neutrino observatory. The search is for magnetic monopoles with speeds above the Cherenkov threshold in ice (∼ 76 % of c), and below 99.5 % of c. I will present the current analysis strategy, the progress made so far, and an outlook on the upcoming work.

Speaker: Alexander Burgman (Uppsala University)

Slides Burgman_171106_Partikeldagarna2017_-_Magnetic_Monopoles.pdf

14:45 The IceCube Upgrade

I will review near-term plans for the IceCube Upgrade, longer-term plans for neutrino astronomy in Antarctica, and the role of Swedish researchers in these efforts.

Speaker: Chad Finley (Stockholm University)

Slides Finley_IceCube_Upgrade_v1.pdf

15:00 ARIANNA Progress Report

Detection of cosmological neutrinos with energies in the energy range 10 PeV - 10 Eev requires efficient detection of signals created in large volumes of matter. A cost effectid method is readout of fast radiopulses from the Askaryan effect caused by neutrno interactions in ice. The ARIANNA project proposes to instrument 1300 km^2 of the Ross Ice shelf with readout stations. I will report on the status of the prototype work and reliability tests done for the ARIANNA project.

Speaker: Prof. Allan Hallgren (Department of Physics and Astronomy, Uppsala University)

Slides Arianna_partikeldag_2017_2.pdf

15:15 → 15:45 Coffee/tea break

15:45 → 17:45 Monday afternoon session 2

15:45 ATLAS Activities at Lund University

The ATLAS group at Lund University is involved in a variety of physics analyses, performance work and detector operation as well as upgrades. This contribution will give an overview of these activities and highlight a few recent results from ATLAS. P.S.: The speaker has to leave around lunch time on Tuesday, so it would be great if this talk could be scheduled before that. (Monday all day is fine.)

Speaker: Oxana Smirnova (Lund University)

Slides Lund-ATLAS-2017.pdf

16:00 ATLAS Activities at Stockholm University

The Stockholm University group is involved in many physics analyses in ATLAS. We conduct searches for new phenomena such as SUSY, dark matter and long-lived particles but also perform precision measurements in e.g. the bottom and top-quark sectors. Furthermore, we are contributing to the development and calibration of algorithms to identify b-jets and to measure the luminosity. We are also involved in maintenance, operation and upgrade activities in the TILE calorimeter and first level calorimeter trigger.

Speaker: Dr Michaël Ughetto (Stockholm University)

Slides 20171107_PartikelDagarna_SUATLAS.pdf

16:15 Search for supersymmetry in the dilepton final state with ATLAS

One of the primary goals of the Large Hadron Collider at CERN is to search for physics beyond the Standard Model. This talk presents a search for Supersymmetry in proton- proton collisions with a centre-of-mass energy of 13 TeV recorded with the ATLAS detector. The analysis is seeking to find events in which supersymmetric particles are produced in proton-proton collisions and then decay into two leptons and a chargeless supersymmetric particle which escapes ATLAS without detection. The search is performed on data collected in 2015 and 2016, corresponding to a total luminosity of 36.1 fb-1. The main Standard Model backgrounds include top-antitop and direct Z boson production and their yields are estimated using two data-driven methods. The results are interpreted in terms of simplified Supersymmetry models of gluino-pair and squark-pair production.

Speaker: Ms Giulia Ripellino (KTH)

Slides ripellino_partikeldagarna_20171106.pdf

16:30 A search for pair-produced resonances in four-jet final states with ATLAS

Massive colored resonances are predicted in many extensions of the Standard Model. In this talk I will present a search for such pair-produced particles which decay into jets using 36.7 fb-1 of sqrt(s)=13TeeV proton-proton collision data recorded with the ATLAS experiment. No significant deviation from the background prediction is observed. The results are interpreted in a SUSY simplified model where the lightest supersymmetric particle is the top squark which decays to two quarks through R-parity violating couplings.

Speaker: Ms Eva Hansen (Lunds Universitet)

Slides slide_pdays.pdf

16:45 Invited speaker Stephan Rosswog

18:30 → 21:00 Conference dinner

Tuesday, 7 November

08:45 → 10:15 Tuesday morning session 1

08:45 Uppsala ATLAS Activities

An overview of the structure, activities and responsibilities of the ATLAS group at Uppsala University is presented. The topics covered range from hardware and software upgrades for the LHC and ATLAS, performance improvements, and searches in Standard Model and Beyond Standard Model physics.

Speaker: Dr Pedro Henrique Sales de Bruin (Uppsala University)

Slides Partikeldagarna.pdf

09:00 A search for Higgs boson pair production in the bbττ channel with the ATLAS experiment

The discovery of the Higgs boson by the ATLAS and CMS experiments in 2012 provided important insight into the mechanism of electroweak symmetry breaking. In the Standard Model (SM), a pair of Higgs bosons can be produced via top quark loops, or the Higgs boson self- coupling. Apart from SM production modes, several beyond the Standard Model (BSM) hypotheses predict heavy narrow width resonances that could decay to a pair of Higgs bosons. A search for non-resonant and resonant Higgs boson pair production in the bbττ channel is presented for 36.1 fb -1 of √s =13 TeV data taken by the ATLAS experiment at the Large Hadron Collider (LHC). Measuring the strength of the Higgs boson trilinear self-coupling will be the ultimate test of the electroweak symmetry breaking mechanism and one of the primary goals of the High Luminosity Large Hadron Collider (HL-LHC) project. A study on the HL-LHC prospects of the SM di-Higgs production in the bbττ channel is presented in addition.

Speaker: Mr Petar Bokan (Uppsala University, Department of Physics and Astronomy)

Slides Partikeldagarna_hhbbtautau_PetarBokan.pdf

09:15 Search for doubly-charged Higgs boson production in multi-lepton final states with the ATLAS detector using proton-proton collisions at √s=13 TeV

A search for doubly-charged Higgs bosons with pairs of prompt, isolated, high-pT leptons with same-sign charge is presented. The search uses the pp collision data sample corresponding to 36.1 fb-1 of integrated luminosity collected in 2015 and 2016 by the ATLAS detector at the LHC with a centre-of-mass energy of 13 TeV. No significant evidence of signal is observed and corresponding limits on the production cross-section are derived. The talk will focus on the analysis strategy, signal region definition and the estimation of the main backgrounds: mis-identified prompt leptons originating from either hadronic jets or secondary weak hadron decays, and electrons with mis-identified charge. Finally, limits on the mass and the production cross-section of the doubly-charged Higgs boson are set.

Speaker: Katja Mankinen (Lund University)

Slides partikeldagarna2017_Mankinen.pdf

09:30 When the NMSSM Meets the LHC: Conventional Higgs Searches and the Power of Mono-Higgs

The Next-to-Minimal Supersymmetric Standard Model (NMSSM) augments the MSSM particle content with an additional singlet superfield. The 125 GeV Standard Model-like Higgs and naturalness generically prefer regions of NMSSM parameter space featuring a light Higgs and neutralino spectrum as well as large couplings between the Higgs doublets and the NMSSM singlet. The additional states and large couplings modify the collider phenomenology of the NMSSM's Higgs sector substantially with respect to the MSSM. This warrants specific search strategies beyond those for MSSM Higgses. I will discuss how Higgs to Higgs and Higgs to neutralino decays can be employed to search for the NMSSM at the LHC. In particular, I will show the potential of the mono-Higgs signature to explore interesting regions of NMSSM parameter space.

Speaker: Sebastian Baum (Stockholm Universitet)

Slides SB_Partikeldagarna.pdf

09:45 Composite Higgs and timid composite pseudo-scalars

In this talk I will review some topics of composite Higgs models. These can successfully address the origin of the Higgs boson, as a pseudo-Goldstone of a spontaneously broken global symmetry, and flavour physics via the partial compositeness mechanism. Models which contain a Higgs and top partners at the same time can also contain additional light scalars in the composite spectrum. Such new states can have an important role in constraining theses models of partial compositeness. I will also show that a light pseudo-scalar in these formulations can be abundantly produced at the LHC and still be allowed by present searches.

Speaker: Mr Hugo Serodio (Lund University)

Slides Serodio.pdf

10:00 Minimal U(1)-theories, anomalies & collider phenomenology

A neutral and massive vector boson, often called Z', is a common feature of many beyond standard model scenarios. The simplest such models extend the electroweak sector of the SM with an extra U(1)-group, spontaneously broken at some higher scale. In such extensions it is important to ensure that this classical symmetry is not violated by quantum effects - so called anomalies. In a theory with chiral fermions, explicit anomaly cancellation requires relations between the different U(1)-charges of these fermions. It is also possible to cancel the anomalies through a Green-Schwarz mechanism, an effect of integrating out 'heavy physics' (can be attributed to string theory or simply to heavy chiral fermions). In this talk I will discuss Z' phenomenology of minimal U(1)-theories at the LHC, with focus on the constraints imposed by anomaly cancellation. I will discuss similarities and differences between explicit anomaly cancellation and the Green-Schwarz mechanism. This talk is in part based on arXiv:1605.04855, in part on a forthcoming paper.

Speaker: Mr Johan Löfgren (Uppsala University)

Slides ZPGS.pdf

10:15 → 10:45 Coffee/tea break

10:45 → 12:45 Tuesday morning session 2

10:45 News from IPPOG

News and the summary of the latest meeting for the International Particle Physics Outreach Group (IPPOG) collaboration.

Speaker: Dr Jonas Strandberg (KTH)

Slides IPPOGReport.pdf

11:00 VR

Speaker: Prof. Kerstin Jon-And (Stockholms universitet)

Slides VR_Partikeldagarna2017..pdf

11:20 RFI

Speaker: Dr Richard Brenner (Uppsala University)

Slides Partikeldagar_RFI2017.pdf Partikeldagar_RFI2017.pdf

11:40 VR panel 2017 and statistics

Speaker: Prof. Johan Bijnens (Lund University)

Slides partikel17.pdf

12:00 IUPAP-C11 Particles and Fields

I will briefly present the activities of the IUPAP-C11 Particles and Fields committee.

Speaker: Johan Rathsman (Lund University)

Slides IUPAP-C11.pdf

12:10 IUPAP C4

An update on what is happening in the IUPAP C4 Commission

Speaker: Prof. Joakim Edsjö (Dept. of Physics, Stockholm University and the Oskar Klein Centre)

ICRC2019 https://uwmadison.eventsair.com/QuickEventWebsitePortal/icrc/2019

IUPAP http://iupap.org

Slides 171107-Edsjo-IUPAP-C4.pdf

12:20 Vote for section board

Slides BoardElpa.pdf

12:35 Discussion

12:45 → 13:45 Lunch

13:45 → 15:15 Tuesday afternoon session 1

13:45 Axions and Axion-Like Particles as the Cold Dark Matter

I revise the axion as a cosmological probe and a cold dark matter candidate, in both standard and modified thermal histories of the Universe. I will also discuss about the possibility that dark matter is in the form of "ultra-light" axions.

Speaker: Dr Luca Visinelli (Stockholm U. and Nordita)

Slides Visinelli_SU2017.pdf

14:00 Axion search with the CASPEr experiment

Axions and axion like particles (ALPs) belong to a class of well motivated dark matter candidates. A variety of techniques are employed in several experimental efforts to directly detect them. An oscillating axion field can exert a time-varying torque on the nuclear spins; such spin precession can be detected using nuclear magnetic resonance techniques, as in the Cosmic Axion Spin Precession Experiment (CASPEr). An overview of the CASPEr experimental efforts will be presented highlighting the various phases of the program and their expected sensitivities to the axion parameter space.

Speaker: Dr Alfredo Davide Ferella (Stockholm University)

Slides CASPEr_Ferella.pdf

14:15 Determining dark matter particle properties with direct detection experiments

Direct detection experiments search for nuclear recoil events induced by the non- relativistic scattering of Milky Way dark matter (DM) particles in low-background detectors. Current strategies for the experimental analysis and theory interpretation of direct detection experiments focus on two parameters: the DM particle mass, and the cross-section for DM-nucleon scattering computed under the assumption of spin- independent or spin-dependent DM-nucleon interactions. In this framework, the DM particle spin remains unconstrained. In my talk, I introduce two new analysis strategies relying on the most general classification of single mediator models for DM- quark interaction. A first strategy potentially allows to extract the DM particle spin in the presence of a signal at direct detection experiments with directional sensitivity. A second strategy shows that a signal at XENONnT together with the detection, or lack of detection, of a mono-jet signal at the LHC Run 3 would significantly narrow the range of possible DM interactions and spins. This work is performed within the Swedish consortium for Dark matter Direct Detection (SweDCube), which links theoretical groups at the Chalmers University of Technology with the experimental group in XENON at the Stockholm University. SweDCube's goals and mission will also be reviewed in the talk.

Speaker: Dr Riccardo Catena (Chalmers University of Technology)

Slides catena.pdf

14:30 Nuclear structure calculations for dark matter searches

In this contribution we will report on calculations of reaction rates for dark matter particles scattering off selected nuclear targets relevant for dark matter direct detection experiments. A model-independent effective field theory approach was used to construct the most general form of low-energy dark matter particle-nucleus interaction. The resulting nuclear matrix elements were evaluated with nuclear wave functions computed within an ab initio many-body framework employing realistic state-of-the-art nuclear interactions derived from chiral effective field theory. In this work, we focused in particular on quantification of systematic nuclear-structure uncertainties and their propagation to physical observables.

Speaker: Dr Daniel Gazda (Chalmers University of Technology)

Slides gazda_partikeldagarna2017.pdf

14:45 LDMX - A Light Dark Matter eXperiment

The origin and observed abundance of Dark Matter in the Universe can be explained elegantly by the thermal freeze-out mechanism, leading to a preferred mass range of the Dark Matter particles in the MeV-TeV region. The GeV-TeV mass range is being explored intensely by the variety of experiments searching for Weakly Interacting Massive Particles. The sub-GeV region, however, in which the masses of most of the building blocks of stable matter lie, is hardly being tested experimentally to date. This mass range occurs naturally in Hidden Sector Dark Matter models. The Light Dark Matter eXperiment (LDMX) is a planned electron-beam fixed-target missing-momentum experiment, that has unique potential to conclusively test models for such light Dark Matter in the MeV to GeV range. This contribution will give an overview of the theoretical motivation, the main experimental challenges and how they are addressed as well as the projected sensitivities in comparison to other experiments.

Speaker: Ruth Pöttgen (Lund University)

LDMX one-pager LDMX_onepage.pdf

Slides LDMX_Partikeldagarna2017_RP.pdf

15:00 Determining Dark Matter properties with a XENONnT/LZ signal and LHC-Run3 mono-jet searches

We develop a method to forecast the outcome of the LHC Run 3 based on the hypothetical detection of O(100) signal events at XENONnT. Our method relies on a systematic classification of renormalisable single-mediator models for dark matter- quark interactions, and is valid for dark matter candidates of spin less than or equal to one. Applying our method to simulated data, we find that at the end of the LHC Run 3 only two mutually exclusive scenarios would be compatible with the detection of O(100) signal events at XENONnT. We therefore conclude that the observation of such a direct detection signal combined with the detection, or the lack of detection, of a mono-jet signal at the LHC Run 3 would significantly narrow the range of possible dark matter-nucleon interactions. As we will also discuss, it can furthermore provide key information on the dark matter particle spin.

Speaker: Dr Martin Krauss (CHALMERS UNIVERSITY OF TECHNOLOGY)

Slides presentation_krauss.pdf

15:15 → 15:45 Coffee/tea break

15:45 → 17:00 Tuesday afternoon session 2

15:45 KTH ATLAS Activities

Overview of the ATLAS activities at KTH

Speaker: Dr Christian Ohm (KTH)

Slides KTH_ATLAS_Ohm.pdf

16:00 Luminosity measurement from track counting in ATLAS

One of the important physics quantities for a collider experiment is luminosity — a measurement of a number of collisions. By knowing the luminosity, the cross-section of a process can be obtained. The ATLAS detector has a subdetector dedicated for luminosity measurement called LUCID. Another complementary approach for luminosity determination is by measuring the number of tracks from charged particles inside the inner detector. The average number of tracks per event is linearly proportional to the average number of inelastic collisions per bunch crossing and can be used to calculate luminosity. The luminosity results in 2016 data, as well as preliminary results in 2017 data, from track counting are presented and compared with results from LUCID.

Speaker: Patrawan Pasuwan (Stockholm University)

Slides Partikeldagarna_PPasuwan_171103.pdf

16:15 Subleading colour corrections in Herwig

We have implemented subleading colour corrections for the dipole parton shower in the event generator Herwig. This has been used to investigate the effects of keeping the full colour structure for parton emissions in both a LEP and an LHC setup. Preliminary results show that, while these corrections typically are small for LEP-observables, they can be several ten percent at the LHC, even for standard QCD observables.

Speaker: Mr Johan Thorén (Lund University)

Slides cmec_johant.pdf

16:30 Lund ALICE group presentation

News from the Lund ALICE group.

Speaker: Dr Peter Christiansen (Lund University)

Slides p_christiansen_lund_alice_split.pdf

16:45 The HIBEAM experiment at the ESS

The HIBEAM experiment is the first stage of a proposed experiment at the European Spallation Source to search for baryon number violation via the conversion of neutrons to anti-neutrons and/or mirror neutrons. The experiment addresses fundamental topical and open questions in modern physics such as baryogenesis and dark matter. In this talk, the goals and status of the HIBEAM experiments are described.

Speaker: Prof. David Milstead (Fysikum, SU)

Slides hbupload.pdf