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Additive Manufacturing (AM) enables 3D metallic objects to be built by adding layer- upon-layer of material. This technology can be applied to produce Ultra High Vacuum components for particle accelerators. We investigated in this work the reproducibility of AM 316L stainless steel properties for different specimens supplied by several manufacturers with the same process. Microstructure and mechanical properties of AM samples depends on manufacturers: indeed, they are largely influenced by processing parameters, which produces heterogeneous and anisotropic microstructures that differ from traditional wrought counterparts. The outgassing rates of vacuum AM 316L tubes were determined and the secondary electron yield was also measured. Results are very promising to consider the use of AM to construct accelerator beam pipe components.

Following previous results which have shown that some components built using additive manufacturing (3D printing) are compatible with ultra high vacuum, we have adapted the design of a stripline BPM to the requirements of additive manufacturing and built it. We report here on the design adaptation and on its mechanical and electrical performances.

The Q & U Bolometric Interferometer for Cosmology (QUBIC) is a cosmology experiment that aims to measure the B-mode polarization of the cosmic microwave background (CMB). Measurements of the primordial B-mode pattern of the CMB polarization are in fact among the most exciting goals in cosmology as it would allow testing of the inflationary paradigm. Many experiments are attempting to measure the B-modes, from the ground and the stratosphere, using imaging Stokes polarimeters. The QUBIC collaboration developed an innovative concept to measure CMB polarization using bolometric interferometry. This approach mixes the high sensitivity of bolometric detectors with the accurate control of systematics due to the interferometric layout of the instrument. We present the calibration results for the Technological Demonstrator, before its commissioning in the Argentinian observing site and preparation for first light.

QUBIC is a ground-based experiment aiming to measure the B-mode polarization of the cosmic microwave background. The developed instrument is an innovative two-frequency band bolometric interferometer that will operate at 300 mK with NbSi TES arrays. In this paper, we describe the fabrication process of the detectors.

Gut evacuation time is a very useful parameter that allows us to understand the daily trophic cycle of a predator. Macrobrachium borellii is an inhabitant of the littoral-benthic community of the Paraná River system that preys on various organisms. In this work, three types of prey (cladocerans, dipteran larvae, and oligochaetes), which are different in shape and mobility, were offered to M. borellii to investigate the gut evacuation time of each one. All prey represent the natural diet of this prawn based on previous work. Results showed a faster digestion of cladocerans than mosquito larvae and oligochaete. These last two types of prey are cylindrical and may interfere with the maceration process in a stomach that lacks a gastric mill. In addition, the high mobility of cladocerans and mosquito larvae implies greater energy expenditure in their capture. However, cladocerans are the prey with the lowest caloric value per individual and therefore offers the lowest net energy to the prawn. This implies that a cladoceran diet would require higher daily consumption and more time foraging, and thus potentially exposing the prawn to greater predation risk. All of these factors direct selection toward the more profitable prey (oligochaetes and dipteran larvae), in agreement with the natural diet observation, suggesting that the time of digestion may have little importance in prey selection.

The Belle II experiment at the SuperKEKB e + e − collider is preparing for an upgrade of its vertex detector to cope with an increased luminosity of up to 6 × 10 35 cm −2 s −1 . The new vertex detector (VTX) will consist of six layers of depleted monolithic active pixel sensors (DMAPS), with a total material budget of about 3% of X 0 . The OBELIX chip, developed for this upgrade, is derived from the TJ-Monopix2 sensor and manufactured using the Tower Semiconductor 180 nm CMOS technology. It features a 33 µ m pixel pitch, time-stamping capability with 50 ns resolution, and a dedicated digital periphery compatible with the Belle II trigger system, supporting rates up to 30 kHz. The sensor is designed to operate under the expected background hit rate at the target luminosity, with high radiation tolerance, up to 5 × 10 14 n eq /cm 2 and 1 MGy, while maintaining a power density in the range of 200-300 mW/cm 2 , corresponding to hit rates from a few MHz/cm 2 up to 120 MHz/cm 2 . This paper presents results from laboratory measurements and beam tests performed on TJ-Monopix2 chips, including both not-irradiated and irradiated devices. Particular focus is given to the performance of irradiated sensors as a function of temperature, a key aspect for defining the maximum allowable operating temperature for OBELIX. These studies provide essential input for the thermal design of the VTX cooling system, especially for the innermost layers where power density and hit rates are highest.

Q & U Bolometric Interferometer for Cosmology (QUBIC) is an international ground-based experiment dedicated in the measurement of the polarized fluctuations of the Cosmic Microwave Background. It is based on bolometric interferometry, an original detection technique which combines the immunity to systematic effects of an interferometer with the sensitivity of low-temperature incoherent detectors. QUBIC will be deployed in Argentina, at the Alto Chorrillos mountain site near San Antonio de los Cobres, in the Salta Province. The QUBIC detection chain consists in 2048 NbSi transition edge sensors (TESs) cooled to 350 mK.The voltage-biased TESs are read out with time domain multiplexing based on Superconducting QUantum Interference Devices at 1 K and a novel SiGe application-specific integrated circuit at 60 K allowing to reach an unprecedented multiplexing factor equal to 128. The QUBIC experiment is currently being characterized in the laboratory with a reduced number of detectors before upgrading to the full instrument. I will present the last results of this characterization phase with a focus on the detectors and readout system.

The Q & U Bolometric Interferometer for Cosmology, QUBIC, is an innovative experiment designed to measure the polarization of the cosmic microwave background and in particular the signature left therein by the inflationary expansion of the Universe. The expected signal is extremely faint; thus, extreme sensitivity and systematic control are necessary in order to attempt this measurement. QUBIC addresses these requirements using an innovative approach combining the sensitivity of transition-edge sensor cryogenic bolometers, with the deep control of systematics characteristic of interferometers. This makes QUBIC unique with respect to others' classical imagers experiments devoted to the CMB polarization. In this contribution, we report a description of the QUBIC instrument including recent achievements and the demonstration of the bolometric interferometry performed in laboratory. QUBIC will be deployed at the observation site in Alto Chorrillos, in Argentina, at the end of 2019.

Measurements of cosmic microwave background (CMB) polarization may reveal the presence of a background of gravitational waves produced during cosmic inflation, providing thus a test of inflationary models. The Q&U Bolometric Interferometer for Cosmology (QUBIC) is an experiment designed to measure the CMB polarization. It is based on the novel concept of bolometric interferometry, which combines the sensitivity of bolometric detectors with the properties of beam synthesis and control of calibration offered by interferometers. To modulate and extract the input polarized signal of the CMB, QUBIC exploits Stokes polarimetry based on a rotating half-wave plate (HWP). In this work, we illustrate the design of the QUBIC instrument, focusing on the polarization modulation system, and we present preliminary results of beam calibrations and the performance of the HWP rotator at 300 K.

Initial surveys in sub-Saharan Africa found a high prevalence of antibodies to human T cell leukemia virus (HTLV), later identified as predominantly HTLV-I. HTLV-II is known to be epidemic among intravenous drug users in the United States and Italy and has recently been identified among Amerindians in the United States, Panama, and Brazil. Its presence in Africa, however, remains discrete, with only sporadic cases having been reported. Delaporte et al., while analyzing samples with polymerase chain reaction (PCR), found several cases of HTLV-II in Gabon, and other reported cases have been found in pygmies from northeastern Zaire, patients in Somalia and Ethiopia, and blood donors in Guinea.