CMS physics technical design report : Addendum on high density QCD with heavy ions

Peer reviewe

The LUX-ZEPLIN (LZ) Experiment

We describe the design and assembly of the LUX-ZEPLIN experiment, a direct detection search for cosmic WIMP dark matter particles. The centerpiece of the experiment is a large liquid xenon time projection chamber sensitive to low energy nuclear recoils. Rejection of backgrounds is enhanced by a Xe skin veto detector and by a liquid scintillator Outer Detector loaded with gadolinium for efficient neutron capture and tagging. LZ is located in the Davis Cavern at the 4850' level of the Sanford Underground Research Facility in Lead, South Dakota, USA. We describe the major subsystems of the experiment and its key design features and requirements

LUX-ZEPLIN (LZ) Technical Design Report

In this Technical Design Report (TDR) we describe the LZ detector to be built at the Sanford Underground Research Facility (SURF). The LZ dark matter experiment is designed to achieve sensitivity to a WIMP-nucleon spin-independent cross section of three times ten to the negative forty-eighth square centimeters

The LUX-ZEPLIN (LZ) experiment

We describe the design and assembly of the LUX-ZEPLIN experiment, a direct detection search for cosmic WIMP dark matter particles. The centerpiece of the experiment is a large liquid xenon time projection chamber sensitive to low energy nuclear recoils. Rejection of backgrounds is enhanced by a Xe skin veto detector and by a liquid scintillator Outer Detector loaded with gadolinium for efficient neutron capture and tagging. LZ is located in the Davis Cavern at the 4850’ level of the Sanford Underground Research Facility in Lead, South Dakota, USA. We describe the major subsystems of the experiment and its key design features and requirements

The LUX-ZEPLIN (LZ) radioactivity and cleanliness control programs

LUX-ZEPLIN (LZ) is a second-generation direct dark matter experiment with spin-independent WIMP-nucleon scattering sensitivity above 1.4×10−48cm2 for a WIMP mass of 40GeV/c2 and a 1000days exposure. LZ achieves this sensitivity through a combination of a large 5.6t fiducial volume, active inner and outer veto systems, and radio-pure construction using materials with inherently low radioactivity content. The LZ collaboration performed an extensive radioassay campaign over a period of six years to inform material selection for construction and provide an input to the experimental background model against which any possible signal excess may be evaluated. The campaign and its results are described in this paper. We present assays of dust and radon daughters depositing on the surface of components as well as cleanliness controls necessary to maintain background expectations through detector construction and assembly. Finally, examples from the campaign to highlight fixed contaminant radioassays for the LZ photomultiplier tubes, quality control and quality assurance procedures through fabrication, radon emanation measurements of major sub-systems, and bespoke detector systems to assay scintillator are presented

Preschoolers’ compliance with simple instructions: A description and experimental evaluation

Thesis (M.A.)--University of Kansas, Applied Behavioral Science, 2007.The present study extends previous research on child compliance by describing compliance levels of 15 preschool-aged children, and then evaluating the effects and limits of antecedent and consequence-based strategies within parametric analyses. Our descriptive assessment, which was administered in a similar manner across pairs of preschoolers, showed that compliance was relatively stable for individual children, variable across children, and was positively correlated with age. The impact of six antecedent variables (proximity, position, physical contact, eye contact, vocal attention, and play interruption) was assessed on compliance with four children. The effects of three-step (vocal, model, physical) prompting were then assessed alone, in combination with the antecedent variables, and at different integrity levels for two children. Results of the experimental analyses showed that compliance gradually increased with the addition of each antecedent variable for two of the four children. Three-step prompting in combination with the six antecedent variables increased compliance to high levels for the remaining two children, and high compliance levels maintained until treatment integrity was deceased to 20% of full strength. Implications for promoting high levels of preschooler compliance in the classroom and for the continued study of preschooler compliance are discussed. Descriptors. antecedent intervention, compliance, preschoolers, three-step prompting, treatment integrity

An Evaluation of Intraverbal Training to Generate Socially Appropriate Responses to Novel Questions

Four preschool children (with and without disabilities), who often responded inappropriately to questions, participated in the current study. Pretest results were used to create sets of questions that the children either did or did not answer correctly (i.e., known and unknown questions). We then sequentially taught two different responses to a subset of unknown questions: (a) “I don't know” (IDK), and (b) “I don't know, please tell me” (IDKPTM). Results showed that following acquisition with the target set, both responses generalized across questions and teachers for all participants. Following IDK training, some undesirable generalization of IDK to known questions occurred for 3 participants. Training of IDKPTM with the addition of a restricted reinforcement contingency was sufficient to establish correct answers to a portion of previously unknown questions. The importance of teaching generalized responses that enable the acquisition of novel intraverbals is discussed