Run 1b Research Articles

Axion Dark Matter Experiment: Detailed designand operations.

Axion dark matter experiment ultra-low noise haloscope technology has enabled the successful completion of two science runs (1A and 1B) that looked for dark matter axions in the 2.66-3.1μeV mass range with Dine-Fischler-Srednicki-Zhitnisky sensitivity [Du et al., Phys. Rev. Lett. 120, 151301 (2018) and Braine et al., Phys. Rev. Lett. 124, 101303 (2020)]. Therefore, it is the most sensitive axion search experiment to date in this mass range. We discuss the technological advances made in the last several years to achieve this sensitivity, which includes the implementation of components, such as the state-of-the-art quantum-noise-limited amplifiers and a dilution refrigerator. Furthermore, we demonstrate the use of a frequency tunable microstrip superconducting quantum interference device amplifier in run 1A, and a Josephson parametric amplifier in run 1B, along with novel analysis tools that characterize the system noise temperature.

Axion dark matter experiment: Run 1B analysis details

Searching for axion dark matter, the ADMX collaboration acquired data from January to October 2018, over the mass range 2.81--3.31 $\mu$eV, corresponding to the frequency range 680--790 MHz. Using an axion haloscope consisting of a microwave cavity in a strong magnetic field, the ADMX experiment excluded Dine-Fischler-Srednicki-Zhitnisky (DFSZ) axions at 100% dark matter density over this entire frequency range, except for a few gaps due to mode crossings. This paper explains the full ADMX analysis for Run 1B, motivating analysis choices informed by details specific to this run.

Formulation and Characterization of Adhesive Produced From Polystyrene Waste Using Response Surface Optimization

Polystyrene is extensively used in building and construction industry, packaging and transportation of fragile equipment due its low density, high melting point, low thermal conductivity, low water absorption, etc. Polystyrene after usage is usually discarded thereby causing environmental problems. The post-usage of polystyrene has, therefore, been a subject of intense research in recent times. The aim of this work is to produce adhesive from polystyrene wastes. Polystyrene waste (PS) was collected, processed and dissolved in tackifyer and formulated with diphnyle amine and diethylene glycol dibenzoate additives to produce adhesive using 3 levels variables factors and 4 levels testing factors of design expert optimization software. The produced adhesive was further characterized for viscosity, pH, percentages solid and moisture contents for their response surfaces. The results showed that the best fit viscosity for each run was Run 1B> Run 5A > Run 5D> Run 5B>Run 4D based on the regression analysis and analysis of variance (ANOVA). The pH values obtained ranged from 4.0 to 6.3; percentage moisture content was in the order of Run 1B < 5A<4D<4B and percentage solid content was in the order of Run 1B<5A<4D. The best fitted adhesive was run 1B with 5.93 % moisture content; 5A has 7.57 % moisture content and 4D with 8.76% moisture content. The percentage solid content; Run 1B has 67.19 %, 5A has 68.16 % and 4D has 75.50 %. The produced adhesives were found within the standard range of adhesives used in production of particleboard.

Inclusive jet production, parton distributions, and the search for new physics

Jet production at the Tevatron probes some of the smallest distance scales currently accessible. A gluon distribution that is enhanced at large x compared to previous determinations provides a better description of the Run 1b jet data from both CDF and D0. However, considerable uncertainty still remains regarding the gluon distribution at high x. In this paper, we examine the effects of this uncertainty, and of the remaining uncertainties in the NLO QCD theory, on jet cross section comparisons to Run 1b data. We also calculate the range of contributions still possible from any new physics. Predictions are also made for the expanded kinematic range expected for the ongoing Run 2 at the Tevatron and for the LHC.

A Comparison of the Underlying Event in Jet and Minimum Bias Events

In order to determine more accurately the energy contribution in a jet cone due to the underlying event, and in oder to understand better the ambient event environment at both the Tevatron and the LHC, a study has been carried out in CDF of the energy distribution in a cone of radius 0.7 in both jet and in minimum bias events. The results from CDF data from Run 1b have been compared with results from [Formula: see text] passed through the detector simulation program QFL.2

Three-jet Event Properties at CDF

The properties of three-jet events in data of integrated luminosity 86±4 pb -1 from CDF Run 1b with a trigger on total ∑ E T > 175 GeV have been analyzed and compared to predictions from a next-to-leading order perturbative QCD calculation. Special emphasis has been placed on analysis of the Dalitz variables.

Recent CDF results

Preliminary results form the CDF detector, based on analysis of data collected in Run 1a and Run 1b at the Tevatron, totaling 110 pb{sup - 1} integrated luminosity, place new limits on the masses and couplings of new particles including charged Higgs bosons, supersymmetric gauge particles and quarks, and new vector bosons. One of the observed events, having an {ital e}{sup +}{ital e}{sup -} pair, two photons, and large missing energy would not occur with significant rate in the Standard Model, leading to speculation regarding its origin and the possible existence of related events.