Scintillation and optical properties of xenon-doped liquid argon

Liquid argon (LAr) is a common choice as detection medium in particle physics and rare-event searches. Challenges of LAr scintillation light detection include its short emission wavelength, long scintillation time and short attenuation length. The addition of small amounts of xenon to LAr is known to improve the scintillation and optical properties. We present a characterization campaign on xenon-doped liquid argon (XeDLAr) with target xenon concentrations ranging from 0 to 300 ppm by mass encompassing the measurement of the photoelectron yield Y, effective triplet lifetime τ 3 and effective attenuation length λ att. The measurements were conducted in the Subterranean Cryogenic ARgon Facility, Scarf, a 1 t (XeD)LAr test stand in the shallow underground laboratory (UGL) of TU-Munich. These three scintillation and optical parameters were observed simultaneously with a single setup, the Legend Liquid Argon Monitoring Apparatus, Llama. The actual xenon concentrations in the liquid and gaseous phases were determined with the Impurity DEtector For Investigation of Xenon, Idefix, a mass spectrometer setup, and successful doping was confirmed. At the highest dopant concentration we find a doubling of Y, a tenfold reduction of τ 3 to ∼90 ns and a tenfold increase of λ att to over 6 m.

Pemeriksaan GeneXpert Terhadap Tingkat Positivitas Pemeriksaan Basil Tahan Asam (BTA) Metode Ziehl Neelsen Pada Penderita Suspek TB Paru

Tuberkulosis (TB) merupakan penyakit infeksi bakteri menahun yang disebabkan oleh Mycobacterium tuberkulosis, suatu basil tahan asam yang ditularkan melalui udara. Tujuan penelitian ini Untuk mengetahui hubungan hasil pemeriksaan GeneXpert dengan tingkat positivitas pemeriksaan BTA Metode Ziehl Neelsen pada penderita Suspek TB Paru. Jenis penelitian ini merupakan penelitian analitik observasi desain cross sectional. Hasil Penelitian penderita Suspek TB Paru sebanyak 190 sampel dengan jenis kelamin laki-laki sebanyak 97 sampel (51,1%) dan perempuan sebanyak 93 sampel (48,9%), Hasil pemeriksaan GeneXpert pada penderita Suspek TB Paru didapatkan hasil pada metode GeneXpert, MTB Not Detection sebanyak 147 orang, MTB Detection Low sebanyak 20 orang, MTB Detection Medium sebanyak 17 orang, MTB Detection High sebanyak 6 orang. Tingkat Positivitas hasil pemeriksaan BTA Metode Ziehl Neelsen metode Ziehl Neelsen didapatkan hasil negatif sebanyak 147 orang, hasil positif Satu (1+) sebanyak 20 orang, hasil positif Dua (2+) sebanyak 17 orang dan hasil positif Tiga (3+) sebanyak 6 orang. Terdapat hubungan yang bermakna antara metode GeneXpert dengan BTA metode Ziehl Neelsen yang mana nilai significance <0,05 yaitu 0,00.

Liquid Argon Instrumentation and Monitoring in LEGEND-200

LEGEND is the next-generation experiment searching for the neutrinoless double beta decay in 76Ge. The first stage, LEGEND-200, takes over the cryogenic infrastructure of GERDA at LNGS: an instrumented water tank surrounding a 64 m3 liquid argon cryostat. Around 200 kg of Ge detectors will be deployed in the cryostat, with the liquid argon acting as cooling medium, high-purity passive shielding and secondary detection medium. For the latter purpose, a liquid argon instrumentation is developed, based on the system used in GERDA Phase II. Wavelength shifting fibers coated with TPB are arranged in two concentric barrels. Both ends are read out by SiPM arrays. A wavelength shifting reflector surrounds the array in order to enhance the light collection far from the array. The LLAMA is installed in the cryostat to permanently monitor the optical parameters and to provide in-situ inputs for modeling purposes. The design of all parts of the LEGEND-200 LAr instrumentation is presented. An overview of the geometry, operation principle, and off-line data analysis of the LLAMA is shown.

Determination of the response function of the NaI detector for g-quanta with an energy of 4.43 MeV, formed during inelastic scattering of neutrons with an energy of 14.1 MeV on carbon nuclei

The work is devoted to determining the response function of the detector NaI(Tl) for g -quanta with energy of 4.43 MeV, formed during inelastic scattering of neutrons with energy of 14.1 MeV on the nuclei 12C. In gamma spectrometry, output pulses are recorded, the amplitudes of which are proportional to the energy lost in the detection medium by incident photons. One of the main tasks of radiation detection is to restore radiation characteristics from signals measured at the outputs of detectors. For this, it is necessary to know, first of all, the general characteristics of detectors as converters of radiation into signals. The main characteristic of the detector is its response function, which can be defined as the probability that a particle with given properties generates a certain signal in the detector that will be registered by the device. The article presents the results of modeling the response function of a scintillation detector based on a NaI(Tl) crystal for gamma radiation from inelastic fast neutron scattering in order to study the mechanism of its formation.

Rancang bangun sensor PH menggunakan gold – extended gate field effect transistor

ABSTRAK Banyak peneliti telah mengembangkan berbagai jenis biosensor, salah satunya sensor pH memanfaatkan MOSFET. Penelitian awal digunakan ISFET sebagai pendeteksi derajat keasamaan, seiring perkembangan teknologi digunakan EGFET sebagai media pendeteksi pH. Karena kelebihan dari EGFET yang lebih stabil dan tahan terhadap gangguan dari luar. Penelitian ini bertujuan untuk mengetahui performansi dari sensor pH berbasis Gold-EGFET dengan tingkat ketebalan lapisan membrane sensor yang berbeda pada pengukuran menggunakan pH buffer yang berbeda. Penelitian ini akan menguji tingkat sensitivitas dan linearitas dari pengukuran pH dengan ketebalan lapisan deteksi dari membrane sensor. ABSTRACT Many researchers have developed various types of biosensors, one of which is a pH sensor utilizing MOSFET. Initial research used ISFET as a detector of the degree of acidity, along with technological developments used EGFET as a pH detection medium because the advantages of EGFET are more stable and resistant to outside interference. This study aims to determine the performance of a Gold-EGFET-based pH sensor with a different level of membrane sensor thickness on measurements using different pH buffers. This study will test the sensitivity and linearity of the pH measurement with the thickness of the detection layer of the sensor membrane.

Construct Coil Probe Using GMR Sensor for Eddy Current Testing

Eddy current testing is a widely applied non-destructive technique in different sections of industries. Nowadays eddy current testing is an accurate, widely used and well-understood inspection technique, particularly in the aircraft and nuclear industries. The main purpose of this paper is to construct an eddy current probe by using transmission coil and using a Giant Magneto resistance (GMR) sensor for detection medium. This probe only use a magnetic field to operational in detection of flaws. A transmission coil is an object made from a material that is magnetized and creates its own persistent magnetic field. A GMR-coil probe has been used to inspect two different material of calibration block. Experimental results obtained by scanning A GMR-coil probe over Brass calibration block has 10 slots with different depth from 0.5mm to 5mm and mild steel has 8 slots with different depth from 0.5mm to 4mm are presented. The result prove that GMR-coil probe that operated using a magnetic field and sensor more effective on ferromagnetic material.

WA105: A Large LAr Double Phase TPC Prototype

For the next generation of long baseline neutrino oscillation experiments detectors with several tens of ktons of detection medium will be needed. Liquid argon (LAr) is ideal for this application since it allows the construction of fully sensitive time projection chambers (TPCs). A mandatory step between the current setups and the final detector for the long baseline experiment is the construction of a large prototype to prove the technical feasibility of the scaling. WA105 with a size of 6×6×6 m3 is this intermediate step for the detector concept of a LAr double phase TPC and will be presented in these proceedings.

Simultaneous Immunomagnetic Separation Method for the Detection of Escherichia coli O26, O111, and O157 from Food Samples

We performed a simultaneous immunomagnetic separation (IMS) assay on Shiga toxin–producing Escherichia coli (STEC) serogroups O26, O111, and O157 with immunobeads coated with O26, O111, or O157 antibodies that were simultaneously added to an aliquot of food culture. We also compared the usefulness of CHROMagar STEC medium against various selective isolation agars designed to test for the three serogroups. Samples of sliced beef, ground beef, and radish sprout were artificially contaminated with STEC O26, O111, and O157 strains after incubation in enrichment broth and were subjected to conventional and simultaneous IMS assays. Simultaneous IMS did not affect the sensitivity of target cell detection. For STEC O26, O111, and O157 inoculated into the enriched samples of sliced beef and radish sprout, the detection ability of CHROMagar STEC was similar to or exceeded that of other isolation agars. However for STEC O157 inoculated into ground beef cultures, cefixime tellurite sorbitol MacConkey agar (CT-SMAC) was the superior detection medium. The performance of simultaneous IMS combined with CT-SMAC and CHROMagar STEC detection is similar to that of the Japanese standard method for isolating E. coli O26, O111, and O157. However, the proposed approach involves the same time, materials, and labor costs as the standard E. coli O157 reference procedure but allows detection of three E. coli serotypes rather than a single strain.

Identification of Levica yeasts as a potential ruminal microbial additive

The objective of this study was to identify and characterize yeast strains isolated from the ruminal ecosystem that are capable of enhancing fermentation in bovines that consume high-fibre diets recommended by livestock feed guidelines in Cuba. The yeasts were isolated from the rumen of Holsteincows that had been fed a biofermented product. Isolated colonies were purified, identified, and characterized using biochemical and molecular methods, and their effects on ruminal fermentation were compared by measuring in vitro gas production. Thirteen new strains enhancing gas production with potential use as additives in ruminal fermentation were identified and named Levica. These strains grew successfully in detection medium for non-Saccharomyces wild yeasts and had long survival periods in the rumen. PFGE analysis found four karyotypes and homology of D1/D2 domain of gene 26S rDNA sequence was similar to that of I. orientalis, R. mucilaginosa, P. guilliermondii, and C. tropicalis. Phylogenetic analysis classified the strains into clades A and B. Clade A was further divided into groups AI, AII, BI, and BII. The AI cluster contained Levica (L)23, L24, L29, L33, and formed a monophyletic group with I. orientalis, while group AII contained L18 and formed a monophyletic group with R. muciloginosa. The BI cluster contained L13, L15, L17, L27, L28, and L32, all derived from P.&nbsp;guilliermondii. Cluster BII was composed only of L25 located in a separate subclade, forming a monophyletic group with C. tropicalis. The most useful strain for preparing microbial feed products to improve ruminal fermentation was L25 because it showed an increase in gas production. &nbsp;