Discovery probabilities of Majorana neutrinos based on cosmological data

We discuss the impact of the cosmological measurements on the predictions of the Majorana mass of the neutrinos, the parameter probed by neutrinoless double-beta decay experiments. Using a minimal set of assumptions, we quantify the probabilities of discovering neutrinoless double-beta decay and introduce a new graphical representation that could be of interest for the community

Discovery probabilities of Majorana neutrinos based on cosmological data

We discuss the impact of the cosmological measurements on the predictions of the Majorana mass of the neutrinos, the parameter probed by neutrinoless double-beta decay experiments. Using a minimal set of assumptions, we quantify the probabilities of discovering neutrinoless double-beta decay and introduce a new graphical representation that could be of interest for the community

Radon mitigation during the installation of the CUORE 0νββ0\nu\beta\beta decay detector

CUORE - the Cryogenic Underground Observatory for Rare Events - is an experiment searching for the neutrinoless double-beta ($0\nu\beta\beta$) decay of $^{130}$Te with an array of 988 TeO$_2$ crystals operated as bolometers at $\sim$10 mK in a large dilution refrigerator. With this detector, we aim for a $^{130}$Te $0\nu\beta\beta$ decay half-life sensitivity of $9\times10^{25}$ y with 5 y of live time, and a background index of $\lesssim 10^{-2}$ counts/keV/kg/y. Making an effort to maintain radiopurity by minimizing the bolometers' exposure to radon gas during their installation in the cryostat, we perform all operations inside a dedicated cleanroom environment with a controlled radon-reduced atmosphere. In this paper, we discuss the design and performance of the CUORE Radon Abatement System and cleanroom, as well as a system to monitor the radon level in real time.Comment: 10 pages, 6 figures, 1 tabl

Calibration sources for the LEGEND-200 experiment

In the search for a monochromatic peak as the signature of neutrinoless double beta decay an excellent energy resolution and an ultra-low background around the Q-value of the decay are essential. The LEGEND-200 experiment performs such a search with high-purity germanium detectors enriched in 76Ge immersed in liquid argon. To determine and monitor the stability of the energy scale and resolution of the germanium diodes, custom-made, low-neutron emission 228Th sources are regularly deployed in the vicinity of the crystals. Here we describe the production process of the 17 sources available for installation in the experiment, the measurements of their alpha- and gamma-activities, as well as the determination of the neutron emission rates with a low-background LiI(Eu) detector operated deep underground. With a flux of (4.27±0.60stat±0.92syst)×10−4 n / (kBq⋅s), approximately one order of magnitude below that of commercial sources, the neutron-induced background rate, mainly from the activation of 76Ge, is negligible compared to other background sources in LEGEND-200

Identification of glyphosate-tolerant soybean plants through germination test

Objetivando reduzir o tempo necessário para verificar a presença do gene de tolerância ao herbicida glyphosate (RR), através da aplicação do produto em plantas de soja, ou o custo envolvido na verificação via análise de DNA, em sementes viáveis, realizou-se pesquisa para desenvolver metodologia para identificação de sementes de soja tolerantes a glyphosate em teste de germinação padrão. Foram usadas sementes de seis genótipos sensíveis a glyphosate e de 12 genótipos tolerantes. Os tratamentos foram: aplicação em pulverização cotiledonarlfoliar de solução de glyphosate, na concentração de 8960 mgll, em volume de 100 Ilha de calda (equivalente a 2 g/ha), no quinto dia do início do teste de germinação; aplicação de glyphosate na água de embebição do papel de germinação, nas concentrações de O, 280, 560, 1120,2240,4480,6720 e 8960 mgll. As unidades experimentais foram rolos de papel germiteste, contendo 50 sementes, com oito repetições, totalizando 400 sementes, exceto no tratamento de pulverização foliar, que foram 25 sementes em linha, semeadas no terço superior do papel de germinação. O papel de germinação foi pesado e acrescentou-se solução de glyphosate, nas concentrações estudadas, em volume equivalente a três vezes o peso do papel. O período de avaliação foi de oito dias. Os parâmetros avaliados foram a percentagem de plântulas normais, anormais e mortas. O estudo evidenciou que é possível identificar a presença de sementes de soja tolerantes a glyphosate (RR) pelo teste de germinação em laboratório e que a dose de glyphosate a ser usada no teste é 280 mg/l na água de embebição do substrato de germinação.Since DNA tests are relatively expensive and time-consuming for the detection of the presence of the gene in plant materiais confering glyphosate tolerance to soybean, an experiment was carried out with the objective of developing a rapid and simple laboratory test for identifying glyphosate-tolerant soybean seeds, through standard seed germination tests. Seeds from six susceptible and twelve glyphosate-tolerant genotypes were used. The treatments consisted of cotiledonar/foliar spray of a glyphosate solution at the concentration of 8960 mg/l with 100 Ilha spray volume (equivalent to 2 g/ha) on the fifth day from the beginning of the germination test and soaking of the germination paper with glyphosate solutions at the concentrations of 0, 280, 560, 1120,2240,4480,6720, and 8960 mgll. The experimental units consisted of roIled germtest paper containing 50 seeds, replicated 8 times, except for the foliar spray treatment where 25 seeds were lined on the first third ofthe germtest paper. The germtest paper was weighed and the glyphosate solutions were added according to the treatments, in volume equivalent to three times the paper weight. Percentage of normal, abnormal and dead seedlings was assessed for eight days, by which time germination had ceased. This research demonstrated that it is possible to detect the presence of glyphosate-tolerant soybean seeds by the lab germination test using glyphosate at the rate of280 mg!liter ofthe imbibition water.

Necrose da haste: uma nova virose da soja no Brasil.

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