On variations of arclength with Myers’s and Hawking’s theorems in Riemannian and Lorentzian geometry

We work through the first and second variations of arclength and discuss the rise of index forms and Jacobi fields along with their application in finding conjugate or focal points on Riemannian or Lorentzian manifolds. We then prove two theorems on the maximal distances of two conjugate or focal points along geodesics for manifolds that satisfy certain boundedness conditions for the Ricci tensor. These are Myers’s theorem in Riemannian geometry and Hawking’s theorem in Lorentzian geometry.Peer reviewe

Flavour-dependent jet energy corrections and top quark mass

The top quark is the heaviest elementary particle in the standard model of particle physics. Its substantial mass indicates it may introduce significant corrections to the Higgs potential. Assuming no new physics below the Planck scale and that the interpretation of theory and measurements is right, these corrections and current experimental results imply that the electroweak vacuum lies in a metastable state. It is therefore important to examine how sound the measurements are. The most accurate single measurements of the top quark mass m_t performed by the CMS and ATLAS collaborations at the LHC differ from a similarly precise result of the D0 experiment at the Tevatron by approximately 2.5 GeV. This amounts to almost 3 standard deviations, so that the D0 result lifts the world average top mass value to approximately 173.3 GeV. Since the top quark decays almost exclusively into a bottom quark b and a W boson, many top mass measurement channels depend on the reconstruction of b-jets, sprays of particles originating from bottom quarks. The very high accuracy of the D0 is based on a unique and very precise calibration of the flavour-dependent jet energy scale corrections. In particular, the D0 correction factor for b-jets is notably different from those used by the ATLAS, CDF and CMS collaborations. An accurate reproduction of the D0 b-jet energy scale corrections is performed using standalone Monte Carlo simulations. We investigate the sensitivity of the b-jet correction to various assumptions, suggest improvements to the method and discuss the results’ implications to top mass measurements

Investigating the fluxes and physics potential of LHC neutrino experiments

The initiation of a novel neutrino physics program at the Large Hadron Collider (LHC) and the purpose-built Forward Physics Facility (FPF) proposal have motivated studies exploring the discovery potential of these searches. This requires resolving degeneracies between new predictions and uncertainties in modeling neutrino production in the forward kinematic region. The present work investigates a broad selection of existing predictions for the parent hadron spectra at FASER$\nu$ and the FPF to parameterize expected correlations in the neutrino spectra produced in their decays and to determine the highest achievable precision for their observation based on Fisher information. This allows for setting constraints on various physics processes within and beyond the Standard Model, including neutrino non-standard interactions. We also illustrate how combining multiple neutrino observables could lead to experimental confirmation of the enhanced-strangeness scenario proposed to resolve the cosmic-ray muon puzzle already during the ongoing LHC Run 3.Comment: 21 pages, 5 figure

Varaston turvallisuussuunnitelma

Opinnäytetyössä tehtiin varaston turvallisuussuunnitelma. Suunnitelmassa perehdyttiin siihen, mitä nykyisten kulunvalvontajärjestelmien puitteissa on mahdollista toteuttaa. Opinnäytetyössä selviää, mitä edellytetään turvalliselta varastolta ja kerrotaan kuinka turvallisuusprojekti voitaisiin toteuttaa. Kulunvalvontajärjestelmät ovat nopeasti yleistymässä, ja varastoihin räätälöityjä ohjeistuksia ei ole vielä juurikaan käsitelty. Perehdyimme opinnäytetyön aikana standardeihin, kulunvalvonta- ja rikosilmoitinjärjestelmiin, videovalvontaan ja hälytys- ja turvajärjestelmiin. Tämän opinnäytetyön teoriaosuuden ja oman pohdinnan yhteenvetona syntyi projektisuunnitelma. Suunnitelma on tarkoitettu logistiikkayrityksille, jotka ovat hankkimassa laajempaa turvallisuusjärjestelmää. Työssä käydään läpi vaihe vaiheelta asiat, jotka tulee ottaa huomioon projektin aikana.The aim of this thesis was to make a warehouse security plan. During the process it was discussed what can be done about the current access control systems. In this thesis the requirements of secure warehouse and how the security project could be done were clarified. Access control systems are becoming more and more common, but there are not so many tailored guidelines for warehouses. In this thesis the standards, access control, intrusion detection systems, video surveillance, alarm systems and security systems were researched. As a result of this thesis’s, a project plan that is based on theory and the authors’ own reasoning was made. The plan is made for logistics companies that are going to purchase a more extensive security system. The issues that need to be taken into consideration are presented step by step in this thesis

Single-differential top quark pair production cross sections with running mass schemes at NLO

Single-differential cross section predictions for top quark pair production are presented at next-to-leading order, using running top quark mass renormalization schemes. The evolution of the mass of the top quark is performed in the MSR scheme $m_{\mathrm{t}}^{\textrm{MSR}}(\mu)$ for renormalization scales $\mu$ below the $\overline{\textrm{MS}}$ top quark mass $\overline{m}_{\mathrm{t}}(\overline{m}_{\mathrm{t}})$, and in the $\overline{\textrm{MS}}$ scheme $\overline{m}_{\mathrm{t}}(\mu)$ for scales above. In particular, the implementation of a mass renormalization scale independent of the strong coupling renormalization scale and factorization scale in quantum chromodynamics allows investigating independent dynamical scale variations. Furthermore, the first theoretically consistent extraction of the top quark MSR mass from experimental data is presented.Comment: To appear in the Proceedings of the 41st International Conference on High Energy physics - ICHEP2022, Bologna, Italy, 6-13 July, 202

Varaston turvallisuussuunnitelma

Opinnäytetyössä tehtiin varaston turvallisuussuunnitelma. Suunnitelmassa perehdyttiin siihen, mitä nykyisten kulunvalvontajärjestelmien puitteissa on mahdollista toteuttaa. Opinnäytetyössä selviää, mitä edellytetään turvalliselta varastolta ja kerrotaan kuinka turvallisuusprojekti voitaisiin toteuttaa. Kulunvalvontajärjestelmät ovat nopeasti yleistymässä, ja varastoihin räätälöityjä ohjeistuksia ei ole vielä juurikaan käsitelty. Perehdyimme opinnäytetyön aikana standardeihin, kulunvalvonta- ja rikosilmoitinjärjestelmiin, videovalvontaan ja hälytys- ja turvajärjestelmiin. Tämän opinnäytetyön teoriaosuuden ja oman pohdinnan yhteenvetona syntyi projektisuunnitelma. Suunnitelma on tarkoitettu logistiikkayrityksille, jotka ovat hankkimassa laajempaa turvallisuusjärjestelmää. Työssä käydään läpi vaihe vaiheelta asiat, jotka tulee ottaa huomioon projektin aikana.The aim of this thesis was to make a warehouse security plan. During the process it was discussed what can be done about the current access control systems. In this thesis the requirements of secure warehouse and how the security project could be done were clarified. Access control systems are becoming more and more common, but there are not so many tailored guidelines for warehouses. In this thesis the standards, access control, intrusion detection systems, video surveillance, alarm systems and security systems were researched. As a result of this thesis’s, a project plan that is based on theory and the authors’ own reasoning was made. The plan is made for logistics companies that are going to purchase a more extensive security system. The issues that need to be taken into consideration are presented step by step in this thesis

Improving Yasso15 soil carbon model estimates with ensemble adjustment Kalman filter state data assimilation

Model-calculated forecasts of soil organic carbon (SOC) are important for approximating global terrestrial carbon pools and assessing their change. However, the lack of detailed observations limits the reliability and applicability of these SOC projections. Here, we studied whether state data assimilation (SDA) can be used to continuously update the modeled state with available total carbon measurements in order to improve future SOC estimations. We chose six fallow test sites with measurement time series spanning 30 to 80 years for this initial test. In all cases, SDA improved future projections but to varying degrees. Furthermore, already including the first few measurements impacted the state enough to reduce the error in decades-long projections by at least 1 tCha(-1). Our results show the benefits of implementing SDA methods for forecasting SOC as well as highlight implementation aspects that need consideration and further research.Peer reviewe

Discovering neutrino tridents at the Large Hadron Collider

Neutrino trident production of dilepton pairs is well recognized as a sensitive probe of both electroweak physics and physics beyond the Standard Model. Although a rare process, it could be significantly boosted by such new physics, and it also allows the electroweak theory to be tested in a new regime. We demonstrate that the forward neutrino physics program at the Large Hadron Collider offers a promising opportunity to measure for the first time, dimuon neutrino tridents with a statistical significance exceeding 5⁢, improving on the previous claims at the ∼3⁢ level by the CHARM-II and CCFR collaborations while accounting for additional backgrounds later identified by the NuTeV collaboration. We present predictions for various proposed experiments and outline a specific experimental strategy to identify the signal and mitigate backgrounds, based on “reverse tracking” dimuon pairs in the FASER⁢⁢2 detector. We also discuss prospects for constraining beyond Standard Model contributions to neutrino trident rates at high energies

The LHC as a Neutrino-Ion Collider

Proton-proton collisions at the LHC generate a high-intensity collimated beam of neutrinos in the forward (beam) direction, characterised by energies of up to several TeV. The recent observation of LHC neutrinos by FASER$\nu$ and SND@LHC signals that this hitherto ignored particle beam is now available for scientific inquiry. Here we quantify the impact that neutrino deep-inelastic scattering (DIS) measurements at the LHC would have on the parton distributions (PDFs) of protons and heavy nuclei. We generate projections for DIS structure functions for FASER$\nu$ and SND@LHC at Run III, as well as for the FASER$\nu$2, AdvSND, and FLArE experiments to be hosted at the proposed Forward Physics Facility (FPF) operating concurrently with the High-Luminosity LHC (HL-LHC). We determine that up to one million electron- and muon-neutrino DIS interactions within detector acceptance can be expected by the end of the HL-LHC, covering a kinematic region in $x$ and $Q^2$ overlapping with that of the Electron-Ion Collider. Including these DIS projections into global (n)PDF analyses, specifically PDF4LHC21, NNPDF4.0, and EPPS21, reveals a significant reduction of PDF uncertainties, in particular for strangeness and the up and down valence PDFs. We show that LHC neutrino data enables improved theoretical predictions for core processes at the HL-LHC, such as Higgs and weak gauge boson production. Our analysis demonstrates that exploiting the LHC neutrino beam effectively provides CERN with a "Neutrino-Ion Collider" without requiring modifications in its accelerator infrastructure.Comment: 42 pages, 22 figures. Added detailed studies on fluxes uncertaintie

Evaluation of multivalency as an organization principle for the efficient synthesis of doubly and triply threaded amide rotaxanes

Mono-, di- and trivalent pseudorotaxanes with tetralactam macrocycle hosts and axles containing diamide binding stations as the guests have been synthesised. Their threading behaviour was analyzed in detail by NMR experiments and isothermal titration calorimetry. An X-ray crystal structure of the monovalent pseudorotaxane confirms the binding motif. Double mutant cycle analysis provides the effective molarities and insight into the chelate cooperativity of multivalent binding. While the second binding event in a trivalent pseudorotaxane exhibits a slightly positive cooperativity, the third binding is nearly non-cooperative. Nevertheless, the enhanced binding affinities resulting from the multivalent interaction are the basis for a highly efficient synthesis of di- and trivalent rotaxanes through stoppering the axle termini by “click” chemistry. Evidence for the multiply threaded geometry comes from NMR spectroscopy as well as tandem mass-spectrometric fragmentation experiments of mass-selected rotaxane ions in the gas phase. Furthermore, the trivalent rotaxane can be controlled by external stimuli (chloride addition and removal) which lead to an elevator-type movement of the wheel along the axle