The second part of the The winter conference season is in full swing! 2022 marks the return of full auditoriums and coffee-break chats following UTFSM’s winter break, as one of the most prestiguos universities in Valparaiso welcomes participants to participate presencially or online in the next round of conferences about the ATLAS experiment results regarding LHC Run 2 dataset. These will be the first large-scale, particle physics conferences in Chile to be held in person in the COVID era – reuniting experimentalists and theorists after almost two years of virtual meetings. The conference will begin on Wednesday 22 July, with talks given both in Chile as in Switzerland. ATLAS Collaboration members will be in attendance throughout, presenting a feast of physics results based on the full LHC Run 2 dataset (recorded 2015–2018). As researchers cast their lines into the pool of Run 2 data, they are using ever-more creative bait to lure out rare phenomena. Throughout the conferences, ATLAS scientists will share what they’ve pulled to the surface, including first-of-a-kind observations of Standard Model processes and the most recent insights in the search for new physics. Key results will be explored in physics briefings, with many more presented in conference talks. Explore all of the latest ATLAS results in the links below, which will be updated continuously throughout the course of the year.

This POAP will be given to the annual registered attendees of the 2022 High Energy Physics talks organized by USM and CCTVal. These talks are related to the ATLAS Experiment at CERN. For this POAP, it will be given to those who participate in the talk that will be given during the first week of May (Tuesday the 3rd) by gerorgian student Markov Bravkov. Topic: The Relativistic Quantum World

Following last week’s excellent presentation made by armenian Phd candidate Estevahan Molinian we will continue with our weekly High Energy Physics talks, this time professor Andrey Borquiev will be giving the a talk titled: T H E ω H A D R O N I Z AT I O N S T U D I E S I N T H E N U C L E A R M E D I U M W I T H T H E C L A S S P E C T R O M E T E R A complete picture of the strong interaction must include hadronization, the dynamical process of a free quark forming a color-neutral hadron. To study the hadronization of the vector meson ω(782), we perform semiinclusive deep-inelastic scattering measurements on deuterium, carbon, iron, and lead using data collected with the CLAS detector at Jefferson Lab employing a 5.014 GeV electron beam. To examine nuclear dependence on the hadron formation, we present ω multiplicities of the solid targets relative to those on deuterium as one-dimensional functions of the virtualphoton energy ν, the photon virtuality Q2, the fractional hadron energy zh, and the square of the hadron transverse momentum p2T. This analysis corresponds to the world’s first hadronization studies of the ω meson and hints at a promising future for upcoming CLAS12 and EIC experiments, where more detailed investigations could be achieved.

During March the 1st, following a successful seminar last week with more than 120 attendees, a new weekly ATLAS related talk will be held, as part of the talks organized by the 'Theory Meets Experiment at ATLAS LHC (ACT1406)', which are going to be held at Aula Magna UTFSM, Valparaiso, Chile. The second talk will be given by Dr. David Zakareishvili: ATLAS measurement of the two-particle correlation sensitivity to jets in proton-proton collisions Measurements of two-particle correlations in proton-proton collisions show the presence of long-range correlations along $\Delta\eta$ that are strikingly similar to those seen in heavy-ion collisions. In larger systems, the long-range correlations are known to arise from the collective dynamics of the produced quark-gluon plasma (QGP). The similarity between the $pp$ and heavy-ion measurements raises the possibility that a tiny droplet of the QGP is produced even in $pp$. However, models that attribute the correlation in $pp$ collisions to semi-hard processes can qualitatively reproduce the measurements. Thus performing the $pp$ measurements with distinguishing particles associated with semi-hard processes, such as low-$p_{\mathrm{T}}$ jets, can further elucidate the origin of the long-range correlations. This talk presents a new measurements of two-particle correlations in $pp$ collisions at $\sqrt{s}=13$ TeV with two different particle pair selections. In the first case, tracks associated with jets are excluded from the correlation analysis. This case results in a minor influence on the magnitude of the long-range correlation. In the second case, the two-particle correlations are measured between jet constituents and the underlying-event tracks. In this case, the correlations show no ridge-like structure.

This poap is exclusively for people who attend the HEP Seminar being held at UTFSM during February 22, 2022. More details about the seminar bellow: February 22, 2022 marks the return of the weekly ATLAS related talks, as part of the talks organized by the ‘Theory Meets Experiment at ATLAS LHC’, which are going to be held at Aula Magna UTFSM, Valparaiso, Chile. The first talk will be given by Dr. Arthur Linss: Search for Dark Matter in Invisible Higgs Boson Decays with the ATLAS Detector at the LHC The nature of dark matter is one of the biggest open questions in modern physics. While dark matter accounts for roughly 25 % of the energy density in the Universe, its particle nature remains unknown so far. In this thesis a search for dark matter at the Large Hadron Collider with the ATLAS experiment is presented using proton-proton collision data collected at a center-of-mass energy of 13 TeV. Furthermore, the absolute Monte Carlo based jet energy scale calibration of particle flow jets is presented. The dark matter search targets vector boson fusion Higgs boson production, which is expected to be the most sensitive channel. For the full Run II data set, the background estimates with a focus on multijet processes, the event categorisation, limit setting as well as the interpretation of the result are presented. In absence of a signal excess over the background-only hypothesis, an upper limit is set on the invisible Higgs boson branching fraction. The observed (expected) 95 % CL limit is 0.145 (0.103), which is the best limit ever achieved so far for invisible Higgs boson decays. The result is interpreted in terms of Higgs portal models to set upper limits on the WIMP-nucleon cross section. Moreover, also limits on potential other scalar mediators than the Higgs boson of the Standard Model are set. Email contact: david.felipe.kouyoumdjian@cern.ch Place: Aula Magna, UTFSM. Avenida España 1680 Time: 22/2/2022, 09:00 (GMT-3)