Search For Dark Matter Extra Dimensions And Unparticles In Monojet Events In Proton Proton Collisions At Sqrt S
DOWNLOAD
Download Search For Dark Matter Extra Dimensions And Unparticles In Monojet Events In Proton Proton Collisions At Sqrt S PDF/ePub or read online books in Mobi eBooks. Click Download or Read Online button to get Search For Dark Matter Extra Dimensions And Unparticles In Monojet Events In Proton Proton Collisions At Sqrt S book now. This website allows unlimited access to, at the time of writing, more than 1.5 million titles, including hundreds of thousands of titles in various foreign languages. If the content not found or just blank you must refresh this page
Search For Dark Matter Extra Dimensions And Unparticles In Monojet Events In Proton Proton Collisions At Sqrt S
DOWNLOAD
Author :
language : en
Publisher:
Release Date : 2015
Search For Dark Matter Extra Dimensions And Unparticles In Monojet Events In Proton Proton Collisions At Sqrt S written by and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2015 with categories.
Results are presented from a search for particle dark matter (DM), extra dimensions, and unparticles using events containing a jet and an imbalance in transverse momentum. The data were collected by the CMS detector in proton-proton collisions at the LHC and correspond to an integrated luminosity of 19.7 fb$^{-1}$ at a centre-of-mass energy of 8 TeV. The number of observed events is found to be consistent with the standard model prediction. Limits are placed on the DM-nucleon scattering cross section as a function of the DM particle mass for spin-dependent and spin-independent interactions. Limits are also placed on the scale parameter $M_\mathrm{D}$ in the ADD model of large extra dimensions, and on the unparticle model parameter $\Lambda_\mathrm{U}$. The constraints on ADD models and unparticles are the most stringent limits in this channel and those on the DM-nucleon scattering cross section are an improvement over previous collider results.
Search For Dark Matter And Unparticles In Events With A Z Boson And Missing Transverse Momentum In Proton Proton Collisions At Sqrt S
DOWNLOAD
Author :
language : en
Publisher:
Release Date : 2017
Search For Dark Matter And Unparticles In Events With A Z Boson And Missing Transverse Momentum In Proton Proton Collisions At Sqrt S written by and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2017 with categories.
A search for dark matter and unparticle production at the LHC has been performed using events containing two charged leptons (electrons or muons), consistent with the decay of a Z boson, and large missing transverse momentum. This study is based on data collected with the CMS detector in 2015, corresponding to an integrated luminosity of 2.3 inverse femtobarns of proton-proton collisions at the LHC, at a center-of-mass energy of 13 TeV. No excess over the standard model expectation is observed. Compared to previous searches in this topology, which exclusively relied on effective field theories, the results are interpreted in terms of a simplified model of dark matter production for both vector and axial vector couplings between a mediator and dark matter particles. The first study of this class of models using CMS data at sqrt(s)=13 TeV is presented. Additionally, effective field theories of dark matter and unparticle production are used to interpret the data.
Search For Dark Matter And Unparticles Produced In Association With A Z Boson In Proton Proton Collisions At Sqrt S
DOWNLOAD
Author :
language : en
Publisher:
Release Date : 2016
Search For Dark Matter And Unparticles Produced In Association With A Z Boson In Proton Proton Collisions At Sqrt S written by and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2016 with categories.
A search for evidence of particle dark matter (DM) and unparticle production at the LHC has been performed using events containing two charged leptons, consistent with the decay of a Z boson, and large missing transverse momentum. This study is based on data collected with the CMS detector corresponding to an integrated luminosity of 19.7 inverse femtobarns of pp collisions at the LHC at a center-of-mass energy of 8 TeV. No significant excess of events is observed above the number expected from the standard model contributions. The results are interpreted in terms of 90% confidence level limits on the DM-nucleon scattering cross section, as a function of the DM particle mass, for both spin-dependent and spin-independent scenarios. Limits are set on the effective cutoff scale Lambda, and on the annihilation rate for DM particles, assuming that their branching fraction to quarks is 100%. Additionally, the most stringent 95% confidence level limits to date on the unparticle model parameters are obtained.
Search For Dark Matter With Atlas
DOWNLOAD
Author : Ruth Pöttgen
language : en
Publisher: Springer
Release Date : 2016-06-29
Search For Dark Matter With Atlas written by Ruth Pöttgen and has been published by Springer this book supported file pdf, txt, epub, kindle and other format this book has been release on 2016-06-29 with Science categories.
This thesis describes in detail a search for weakly interacting massive particles as possible dark matter candidates, making use of so-called mono-jet events. It includes a detailed description of the run-1 system, important operational challenges, and the upgrade for run-2. The nature of dark matter, which accounts for roughly 25% of the energy-matter content of the universe, is one of the biggest open questions in fundamental science. The analysis is based on the full set of proton-proton collisions collected by the ATLAS experiment at the Large Hadron Collider at √s = 8 TeV. Special attention is given to the experimental challenges and analysis techniques, as well as the overall scientific context beyond particle physics. The results complement those of non-collider experiments and yield some of the strongest exclusion bounds on parameters of dark matter models by the end of the Large Hadron Collider run-1. Details of the upgrade of the ATLAS Central Trigger for run-2 are also included.
Search For Dark Matter In Final States Containing Semi Visible Jets From Proton Proton Collisions At Square Root S
DOWNLOAD
Author : Colin Terrence Fallon
language : en
Publisher:
Release Date : 2022
Search For Dark Matter In Final States Containing Semi Visible Jets From Proton Proton Collisions At Square Root S written by Colin Terrence Fallon and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2022 with categories.
"This dissertation presents a novel search for new physics using the full Run 2 dataset of 137.6 fb-1 collected by the Compact Muon Solenoid during proton-proton runs of the Large Hadron Collider. The new physics in question is dark matter production in a unique signature called semi-visible jets. Semi-visible jets are produced when a new massive mediator particle emerges from the proton-proton interaction. This mediator then decays to unstable dark matter particles which hadronize and produce a mixture of standard model particles and stable dark matter particles. The stable dark particles are only detectable as missing transverse momentum, and the standard particles are detectable as jets. This produces a signature where two jets are produced, one of which is aligned with the total missing transverse momentum. The search is presented in two phases: a classical cut-based search which uses a series of cuts based on event kinematics to select events which look like the signal signature, and a machine learning based search which uses a technique called boosted decision trees to identify semi-visible jets in a more powerful but model-dependent way. No evidence for Physics Beyond the Standard Model is observed in either search. The classical search excludes the possibility that the mediator could have a mass between 1.5 TeV and 3.98 TeV, while the model-dependent search excludes mediators with masses between 1.5 TeV and 5.08 TeV. Additionally, ranges of other signal parameters are excluded"--Page viii.
Search For Extra Dimensions In Diphoton Events From Proton Proton Collisions At S
DOWNLOAD
Author :
language : en
Publisher:
Release Date : 2016
Search For Extra Dimensions In Diphoton Events From Proton Proton Collisions At S written by and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2016 with categories.
Search For Dark Matter Particles In Proton Proton Collisions At Sqrt S
DOWNLOAD
Author :
language : en
Publisher:
Release Date : 2016
Search For Dark Matter Particles In Proton Proton Collisions At Sqrt S written by and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2016 with categories.
A search for dark matter particles directly produced in proton-proton collisions recorded by the CMS experiment at the LHC is presented. The data correspond to an integrated luminosity of 18.8 inverse femtobarns, at a center-of-mass energy of 8 TeV. The event selection requires at least two jets and no isolated leptons. The razor variables are used to quantify the transverse momentum balance in the jet momenta. The study is performed separately for events with and without jets originating from b quarks. The observed yields are consistent with the expected backgrounds and, depending on the nature of the production mechanism, dark matter production at the LHC is excluded at 90% confidence level for a mediator mass scale Lambda below 1 TeV. The use of razor variables yields results that complement those previously published.
Search For The Production Of Dark Matter In Association With Top Quark Pairs In The Single Lepton Final State In Proton Proton Collisions At Sqrt S
DOWNLOAD
Author :
language : en
Publisher:
Release Date : 2015
Search For The Production Of Dark Matter In Association With Top Quark Pairs In The Single Lepton Final State In Proton Proton Collisions At Sqrt S written by and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2015 with categories.
A search is presented for particle dark matter produced in association with a pair of top quarks in pp collisions at a centre-of-mass energy of s√=8 TeV. The data were collected with the CMS detector at the LHC and correspond to an integrated luminosity of 19.7 fb-1. This search requires the presence of one lepton, multiple jets, and large missing transverse energy. No excess of events is found above the SM expectation, and upper limits are derived on the production cross section. Interpreting the findings in the context of a scalar contact interaction between fermionic dark matter particles and top quarks, lower limits on the interaction scale are set. These limits are also interpreted in terms of the dark matter-nucleon scattering cross sections for the spin-independent scalar operator and they complement direct searches for dark matter particles in the low mass region.
Search For Dark Matter And Unparticles Produced In Association With A Z Boson In Proton Proton Collisions At S
DOWNLOAD
Author : CMS Collaboration
language : en
Publisher:
Release Date : 2015
Search For Dark Matter And Unparticles Produced In Association With A Z Boson In Proton Proton Collisions At S written by CMS Collaboration and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2015 with categories.
A Search For Dark Matter In Events With One Jet And Missing Transverse Energy In P Bar P Collisions At Sqrt S
DOWNLOAD
Author :
language : en
Publisher:
Release Date : 2012
A Search For Dark Matter In Events With One Jet And Missing Transverse Energy In P Bar P Collisions At Sqrt S written by and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2012 with categories.
We present the results of a search for dark matter production in the monojet signature. We analyze a sample of Tevatron pp collisions at √s = 1.96 TeV corresponding to an integrated luminosity of 6.7 fb−1 recorded by the CDF II detector. In events with large missing transverse energy and one energetic jet, we find good agreement between the standard model prediction and the observed data. We set 90% confidence level upper limits on the dark matter production rate. The limits are translated into bounds on nucleon-dark matter scattering rates which are competitive with current direct detection bounds on spin-independent interaction below a dark matter candidate mass of 5 GeV/c2, and on spin-dependent interactions up to masses of 200 GeV/c2.