The CMS Experiment: Status and First Results

After nearly two decades of design, construction and commissioning, the CMS detector was operated with colliding LHC proton beams for the first time in November 2009. Collision data were recorded at centre-of-mass energies of 0.9 and 2.36 TeV, and analyzed with a fast turn-around time by the CMS collaboration. In this talk I will present a selection of commissioning results and striking first physics resonances observed. Then I will discuss the analysis of the transverse momentum and rapidity distribution of charged hadrons, which led to the first CMS physics publication. The excellent performance of the CMS detector and agreement with predictions from simulation are impressive for a collider detector at startup and show a great potential for discovery physics in the upcoming LHC run.Comment: Presented at Moriond/EW: XLVth Rencontres de Moriond on Electroweak Interactions and Unified Theorie

The odour of white bread

Volatile constituents of white bread were investigated. Different methods were used for isolating and concentrating components to avoid artefacts as far as possible. Especially good was enlarged vapour analysis. Ninety-four components were identified, including hydrocarbons, alcohols, aldehydes, ketones, acids, esters as well as nitrogen, sulphur and miscellaneous compounds. The concentration of the main components in the vapour above white bread was determined by direct vapour analysis. The odour threshold values of these components in aqueous solution were determined, and the odour values calculated as the ratio of concentration to odour threshold value to estimate their contribution to the total odour. The Maillard reaction of the cysteine/cystine-ribose system was investigated in a search for components which can be expected in heat-processed food products, and to find out whether during this reaction compounds possessing bread-like odours were formed. Forty-five components were identified, including thiophenes, thiazoles, thiols, pyrazines, pyrroles, amines, furans, aldehydes, ketones and miscellaneous compounds. Possible pathways for the formation of 2-acylthiazoles and of 3-methyl, and 5-methyl substituted 2-formylthiophenes are proposed

The 3D entangled structure of the proton; transverse degrees of freedom in QCD, momenta, spins and more

Light-front quantized quark and gluon states (partons) play a dominant role in high energy scattering processes. Initial state hadrons are mixed ensembles of partons, while produced pure partonic states appear as mixed ensembles of hadrons. The transition from collinear hard physics to the 3D structure including partonic transverse momenta is related to confinement which links color and spatial degrees of freedom. We outline ideas on emergent symmetries in the Standard Model and their connection to the 3D structure of hadrons. Wilson loops, including those with light-like Wilson lines such as used in the studies of transverse momentum dependent distribution functions (TMDs) may play a crucial role here, establishing a direct link between transverse spatial degrees of freedom and gluonic degrees of freedom.Comment: 8 pages, invited talk presented at the Lightcone 2017 Workshop, 18-22 Sep 2017, Mumbai, India; prepared for proceedings to be published in Few Body Physic

Searches for new fermions and new bosons

The high center-of-mass energy at the LHC provides the opportunity to test the predictions of some of the beyond the standard model theories. We provide an overview of a selected number of searches for new fermions and new bosons with the ATLAS and CMS experiments. No evidence for the existence of new particles was found and therefore limits are obtained on the parameters of the models under consideration.Comment: 10 pages, 18 figures, proceeding of PIC2012 conference corrections in section for new W boson modification in section searches for new W boson

Spin Physics and Transverse Structure

Spin is a welcome complication in the study of partonic structure that has led to new insights, even if theoretically and experimentally not all dust has settled, in particular on quark flavor dependence and gluon spin. At the same time it opened new questions on angular momentum and effects of transverse structure. In this talk the focus is on the role of the transverse momenta of partons. Like for collinear parton distribution functions (PDFs), we are also in the case of transverse momentum dependent (TMD) PDFs, talking about forward matrix elements. TMD PDFs (or in short TMDs) extend collinear PDFs with only spin-spin correlations to PDFs that include spin-momentum correlations, including also time-reversal-odd (T-odd) correlations, relevant for the description of single spin asymmetries. In this way TMDs open up new ways of studying the spin structure. Their operator structure within QCD, however, is more complex leading to various ways of breaking of universality.Comment: 8 pages, to appear in proceedings of DIS2015 (XXIII International Workshop on Deep-Inelastic Scattering and Related Subjects, 27 April - 1 May, 2015, Dallas, USA

Top quark properties

The multi-purpose experiments at CERN's Large Hadron Collider have a very rich programme in top quark physics. The large amount of data allows for measuring the top quark properties with an unprecedented precision. This document presents some of the properties that have been measured using top quark pair events produced in proton-proton collisions with a centre-of-mass energy of 13 TeV. The focus lies on the measurements of the colour flow, the charge asymmetry and spin correlations in top quark pair events.Comment: 5 pages, 6 figures, TOP2018 conference proceeding

Current fragmentation in semiinclusive leptoproduction

Current fragmentation in semiinclusive deep inelastic leptoproduction offers, besides refinement of inclusive measurements such as flavor separation and access to the chiral-odd quark distribution functions $h_1^q(x) = \delta q(x)$, the possibility to investigate intrinsic transverse momentum of hadrons via azimuthal asymmetries.Comment: 14 pages, Latex using aipproc.sty and epsfig.sty; plenary talk given at the Second Workshop on Physics with an Electron Polarized light-Ion Collider (EPIC), Sept. 14-16, 2000, MIT, Cambridge, US