The progress in development of the Planck-Balance 2 (PB2): A tabletop Kibble balance for the mass calibration of E2 class weights

In this paper we present the progress in development of a table-top version of the Kibble balance under the name Planck-Balance 2 (PB2). The PB2 is developed as a collaboration effort between the Technische Universität Ilmenau (TU Ilmenau) and Physikalisch-Technische Bundesanstalt (PTB) aiming for automatized mass calibration of the set of weights in the range from 1 mg to 100 g within the required uncertainties as stated by OIML recommendation R111 for weights of E2 class. We describe the design and the operational performance of the PB2 system in detail, the results of rigorous investigations of the error sources and subsequent improvements made since the beginning of the project in early 2017, the measurement data with the corresponding relative uncertainties and the preliminarily obtained uncertainty budget.

Посевные качества нестрелкующегося чеснока в зависимости от положения зубков в луковицах

The location of the cloves influences the growth and development of the plants, as well as the for-mation of the bulb mass. Peripheral garlic cloves are distinguished by higher quality over internal ones (the mass ratio is within 60 : 40%). Our studies show that in obtaining high yields of non-clotting garlic, the location of the clove in the bulb is of decisive importance. Studies also found that the use of cloves of different locations without mass calibration for planting, leads to different times of ripening of the bulbs, which complicates the process of harvesting and leads to a deterioration in the quality of garlic. Sorting, with the aim of using similarly ground garlic cloves for planting, ensures the uniform development of the plants, simultaneous of ripening of the bulbs and obtaining better quality products.

Calibration of bias and scatter involved in cluster mass measurements using optical weak gravitational lensing

Cosmological inference from cluster number counts is systematically limited by the accuracy of the mass calibration, i.e. the empirical determination of the mapping between cluster selection observables and halo mass. In this work we demonstrate a method to quantitatively determine the bias and uncertainties in weak-lensing mass calibration. To this end, we extract a library of projected matter density profiles from hydrodynamical simulations. Accounting for shear bias and noise, photometric redshift uncertainties, mis-centering, cluster member contamination, cluster morphological diversity, and line-of-sight projections, we produce a library of shear profiles. Fitting a one-parameter model to these profiles, we extract the so-called weak lensing mass MWL. Relating the weak-lensing mass to the halo mass from gravity-only simulations with the same initial conditions as the hydrodynamical simulations allows us to estimate the impact of hydrodynamical effects on cluster number counts experiments. Creating new shear libraries for ∼1000 different realizations of the systematics, provides a distribution of the parameters of the weak-lensing to halo mass relation, reflecting their systematic uncertainty. This result can be used as a prior for cosmological inference. We also discuss the impact of the inner fitting radius on the accuracy, and determine the outer fitting radius necessary to exclude the signal from neighboring structures. Our method is currently being applied to different Stage III lensing surveys, and can easily be extended to Stage IV lensing surveys.

Cluster–galaxy weak lensing

Weak gravitational lensing of background galaxies provides a direct probe of the projected matter distribution in and around galaxy clusters. Here, we present a self-contained pedagogical review of cluster–galaxy weak lensing, covering a range of topics relevant to its cosmological and astrophysical applications. We begin by reviewing the theoretical foundations of gravitational lensing from first principles, with a special attention to the basics and advanced techniques of weak gravitational lensing. We summarize and discuss key findings from recent cluster–galaxy weak-lensing studies on both observational and theoretical grounds, with a focus on cluster mass profiles, the concentration–mass relation, the splashback radius, and implications from extensive mass-calibration efforts for cluster cosmology.

Saccharose cluster ions as mass calibrants in positive-ion direct analysis in real time-mass spectrometry

In positive-ion direct analysis in real time-mass spectrometry (DART-MS), mono-, di, and trisaccharides form [M+NH4]+ ions. Some of them, in addition, yield abundant [Mn+NH4]+ cluster ions (n = 1–6)), and thus, can serve for mass calibration. Saccharose, C12H22O11, the most common sugar, also termed sucrose, is among the [Mn+NH4]+ cluster ion forming species. Saccharose may therefore be employed as a cheap and ubiquitous mass calibration standard. The extent of saccharose cluster ion formation depends on the temperature of the DART gas, sample load, and instrumental parameters like trapping conditions of ions prior to mass analysis. This study identifies optimized experimental conditions and demonstrates the application of saccharose cluster ion-based mass calibration for accurate mass measurements in DART mode on a Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer.

Quantifying the statistics of CMB-lensing-derived galaxy cluster mass measurements with simulations

ABSTRACT Cosmic microwave background (CMB) lensing is a promising, novel way to measure galaxy cluster masses that can be used, e.g. for mass calibration in galaxy cluster counts analyses. Understanding the statistics of the galaxy cluster mass observable obtained with such measurements is essential if their use in subsequent analyses is not to lead to biased results. We study the statistics of a CMB lensing galaxy cluster mass observable for a Planck-like experiment with mock observations obtained from an N-body simulation. We quantify the bias and intrinsic scatter associated with this observable following two different approaches, one in which the signal due to the cluster and nearby correlated large-scale structure is isolated, and another one in which the variation due to uncorrelated large-scale structure is also taken into account. For our first approach, we also quantify deviations from lognormality in the scatter, finding them to have a negligible impact on mass calibration for our Planck-like experiment. We briefly discuss how some of our results change for experiments with higher angular resolution and lower noise levels, such as the current generation of surveys obtained with ground-based, large-aperture telescopes.