Production of He-4 and (4) in Pb-Pb collisions at root(NN)-N-S=2.76 TeV at the LHC

Results on the production of He-4 and (4) nuclei in Pb-Pb collisions at root(NN)-N-S = 2.76 TeV in the rapidity range vertical bar y vertical bar <1, using the ALICE detector, are presented in this paper. The rapidity densities corresponding to 0-10% central events are found to be dN/dy4(He) = (0.8 +/- 0.4 (stat) +/- 0.3 (syst)) x 10(-6) and dN/dy4 = (1.1 +/- 0.4 (stat) +/- 0.2 (syst)) x 10(-6), respectively. This is in agreement with the statistical thermal model expectation assuming the same chemical freeze-out temperature (T-chem = 156 MeV) as for light hadrons. The measured ratio of (4)/He-4 is 1.4 +/- 0.8 (stat) +/- 0.5 (syst). (C) 2018 Published by Elsevier B.V.Peer reviewe

An Evaluation of Secure Connection Manager : Focused on Usability and Efficiency

In today’s computerized society more and more companies choose to utilize new applications that can ease the way of handling the information. For many of us is imperative that the process as efficient as possible if one takes in consideration the size of savings that this new application can bring. The developer of the evaluated system is SYSteam AB Huskvarna and they are the ones that gave us this assignment. The application that we evaluate is SCM (Secure Connection Manager). It is already used today by big companies such as Telia and Ericsson to search for errors in telephone servers placed all over the country. The reason why this application is used is to increase the efficiency of error searching without traveling to the location of the servers. The issues that the report focuses on are the system’s usability and efficiency for the user. Since the application is already in use we must be aware that just small adjustments are going to be made afterward. In order to evaluate an already developed system we interviewed users that are familiar with the application and were willing to be answering our questions.Those users’ opinions have been crucial to us and our evaluation. The result is a gathering of tables and data which methodically describes every subject in our questionnaire. These subjects are the following: navigation, design, content and efficiency.  Our analyses results show a positive reaction to almost all the subjects treated in the questionnaires. Several opinions and comments during the interviews confirm this statement.  The theoretical methods used to form this opinion are the heuristics rules that we followed, but also some of the most useful principles from theory books about interaction design. The conclusion is, as the results of our evaluation show, that the system that we evaluated (SCM) is both efficient and user-friendly. We would like to thank all the users, which took part in our study, as well as our supervisors both at university and at SYSteam AB Huskvarna. Thank you!Med dagens mer systematiserade tillvaro är det fler som väljer att införa applikationer i företag som kan underlätta informationshanteringen. För många är det viktigt att detta sker så effektivt som möjligt med tanke på de besparingar som det kan medföra. De som har utvecklat den studerade applikationen och som också är våra uppdragsgivare är SYSteam AB i Huskvarna. Denna applikation som vi utvärderar heter Secure Connection Manager (SCM). Den används idag av bland annat företag som Telia och Ericsson för att göra felsökningar på telefonväxlar som finns utplacerade i landet. Anledningen till att denna applikation används är att det blir mer effektivt att med hjälp av fjärrstyrning kunna göra felsökningar utan att behöva åka till telestationerna som de tidigare har gjort. Frågeställningarna som arbetet fokuserar på är om systemet är användarvänligt och effektivt för användaren. Eftersom systemet redan är i drift måste man ha i åtanke att det endast kan ske marginella justeringar i efterhand. För att kunna evaluera ett färdigt system har vi haft hjälp av ett antal frekventa användare som villigt har ställt upp på att svara på frågor och intervjuer. Dessa testpersoner har varit av yttersta vikt för oss och för vår evaluering. Resultatet blev en samling tabeller och data som metodiskt beskriver varje element var för sig. De element som frågeguiden är indelad i är navigation, design, innehåll och effektivitet. Analysen gav positiva resultat till de frågeställningar vi hade ställt, förutom elementet innehåll. Flera av de synpunkter och kommentarer som samlades in under intervjuerna förstärkte detta resultat. De teoretiska metoder som hjälpte oss att bedöma detta var några av de heuristiska regler som finns att följa, men även några av de principer som finns att läsa om i böcker om interaktionsdesign. Slutsatsen blev att av de resultat vi fick av vår utvärdering konstaterade vi att SCM är både effektivt och användarvänligt. Vi vill gärna rikta ett tack till alla testpersoner som ställde upp och till våra handledare både på högskolan och på SYSteam AB i Huskvarna. Tack

Synch.Live: Collective problem-solving through flocking motion induces higher connectedness to others

Collective self-organising behaviour is ubiquitous in nature, whereby complex patterns emerge from the local interactions between individuals. Yet in humans, most group behaviour is often attributed to explicit central control or social norms, rather than to synergistic interplay between individuals. Here we introduce Synch.Live, a participatory behavioural science experiment for quantitatively studying collective motion in humans, framed as a game with an unspecified task and a group feedback mechanism, that can be solved through cooperation by 10 participants moving together. More than half of the groups participating in the experiment succeeded in achieving flocking motion, and winning players showed higher connectedness to others compared to those who failed. Furthermore, individuals with an awareness of working strategies were more likely to be part of winning groups, suggesting the importance of individual contributions to the collective task. This work demonstrates that solving an unspecified group challenge in response to group feedback is possible, and moreover, that flock-like collective movement has the potential to yield social benefits and well-being, suggesting new directions for exploring social aspects of consciousness and cognition

Growing polarisation around climate change on social media

Climate change and political polarisation are two of the 21st century's critical social and political issues. However, their interaction remains understudied. Here, we investigate the online discussion around the UN Conference of The Parties on Climate Change (COP) using Twitter data from 2014 to 2021. First, we reveal a large increase in ideological polarisation during COP26, following low polarisation between COP20 and COP25. Second, we show that this increase is driven by growing right-wing engagement (a 4-fold increase since COP21). Finally, we study key topics of discussion during COP26, identifying a broad range of ``climate contrarian'' views, and emphasising the theme of ''political hypocrisy'' as a topic of cross-ideological appeal. With future climate action reliant on negotiations at COP27 and beyond, our results highlight the importance of monitoring polarisation in the public climate discourse and how this may impact political action.Comment: 14 pages mai

Growing polarization around climate change on social media

Climate change and political polarization are two of the twenty-first century’s critical socio-political issues. Here we investigate their intersection by studying the discussion around the United Nations Conference of the Parties on Climate Change (COP) using Twitter data from 2014 to 2021. First, we reveal a large increase in ideological polarization during COP26, following low polarization between COP20 and COP25. Second, we show that this increase is driven by growing right-wing activity, a fourfold increase since COP21 relative to pro-climate groups. Finally, we identify a broad range of ‘climate contrarian’ views during COP26, emphasizing the theme of political hypocrisy as a topic of cross-ideological appeal; contrarian views and accusations of hypocrisy have become key themes in the Twitter climate discussion since 2019. With future climate action reliant on negotiations at COP27 and beyond, our results highlight the importance of monitoring polarization and its impacts in the public climate discourse

Multiplicity dependence of light (anti-)nuclei production in p–Pb collisions at sNN=5.02 TeV

The measurement of the deuteron and anti-deuteron production in the rapidity range −1 < y < 0 as a function of transverse momentum and event multiplicity in p–Pb collisions at √sNN = 5.02 TeV is presented. (Anti-)deuterons are identified via their specific energy loss dE/dx and via their time-of- flight. Their production in p–Pb collisions is compared to pp and Pb–Pb collisions and is discussed within the context of thermal and coalescence models. The ratio of integrated yields of deuterons to protons (d/p) shows a significant increase as a function of the charged-particle multiplicity of the event starting from values similar to those observed in pp collisions at low multiplicities and approaching those observed in Pb–Pb collisions at high multiplicities. The mean transverse particle momenta are extracted from the deuteron spectra and the values are similar to those obtained for p and particles. Thus, deuteron spectra do not follow mass ordering. This behaviour is in contrast to the trend observed for non-composite particles in p–Pb collisions. In addition, the production of the rare 3He and 3He nuclei has been studied. The spectrum corresponding to all non-single diffractive p-Pb collisions is obtained in the rapidity window −1 < y < 0 and the pT-integrated yield dN/dy is extracted. It is found that the yields of protons, deuterons, and 3He, normalised by the spin degeneracy factor, follow an exponential decrease with mass number

Pseudorapidity densities of charged particles with transverse momentum thresholds in pp collisions at √ s = 5.02 and 13 TeV

The pseudorapidity density of charged particles with minimum transverse momentum (pT) thresholds of 0.15, 0.5, 1, and 2 GeV/c is measured in pp collisions at the center of mass energies of √s=5.02 and 13 TeV with the ALICE detector. The study is carried out for inelastic collisions with at least one primary charged particle having a pseudorapidity (η) within 0.8pT larger than the corresponding threshold. In addition, measurements without pT-thresholds are performed for inelastic and nonsingle-diffractive events as well as for inelastic events with at least one charged particle having |η|2GeV/c), highlighting the importance of such measurements for tuning event generators. The new measurements agree within uncertainties with results from the ATLAS and CMS experiments obtained at √s=13TeV.