Changes during storing and astringency removal of persimmon fruit Diospyros kaki L.

Physiological changes during ripening, storing and astringency removal of persimmon fruits were traced. The fruits were stored under normal (NA), controlled (CA) and vacuum atmospheres (VA). The fruits were stored for 100 days and analysed for firmness, acetaldehyde and ethanol content and soluble tannins, both before and after storing. The same analyses were done during the deastringency treatment carried out with a high CO2 concentration (99.99%) for 20 h at 20 °C. The persimmon fruits stored under NA, CA, VA or treated with high CO2 for 20 h accumulated acetaldehyde and ethanol in the fruit tissue. CA conditions caused the highest acetaldehyde accumulation; vacuum conditions the lowest. Ethanol content increased 20 fold during storage; the highest accumulation was observed in vacuum stored fruit followed by CA (3% CO2Ś2% O2 and 0.5% CO2Ś2% O2) conditions. Astringency removal treatment caused an immediate increase of acetaldehyde and ethanol, nearly to the same extent as in conventionally ripened or stored fruit. The amount of soluble tannins, the main cause of an astringent taste, decreased during storage, and it did much faster during deastringency removal at the same level. The sensory evaluation test revealed that fruit treated with high CO2 was preferred to conventionally ripened fruit

Arrival Directions of Cosmic Rays above 32 EeV from Phase One of the Pierre Auger Observatory

A promising energy range to look for angular correlations between cosmic rays of extragalactic origin and their sources is at the highest energies, above a few tens of EeV (1 EeV ≡ 1018 eV). Despite the flux of these particles being extremely low, the area of ∼3000 km2 covered at the Pierre Auger Observatory, and the 17 yr data-taking period of the Phase 1 of its operations, have enabled us to measure the arrival directions of more than 2600 ultrahigh-energy cosmic rays above 32 EeV. We publish this data set, the largest available at such energies from an integrated exposure of 122,000 km2 sr yr, and search it for anisotropies over the 3.4π steradians covered with the Observatory. Evidence for a deviation in excess of isotropy at intermediate angular scales, with ∼15° Gaussian spread or ∼25° top-hat radius, is obtained at the 4σ significance level for cosmic-ray energies above ∼40 EeV.Fil: Abreu, P.. Instituto Superior Tecnico; Portugal. Universidade Nova de Lisboa; PortugalFil: Aglietta, M.. Istituto Nazionale di Astrofisica; Italia. Istituto Nazionale di Fisica Nucleare; ItaliaFil: Albury, J.M.. University of Adelaide; AustraliaFil: Allekotte, Ingomar. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; ArgentinaFil: Mollerach, Maria Silvia. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro. Archivo Histórico del Centro Atómico Bariloche e Instituto Balseiro | Universidad Nacional de Cuyo. Instituto Balseiro. Archivo Histórico del Centro Atómico Bariloche e Instituto Balseiro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Almeida Cheminant, K.. Polish Academy Of Sciences; PoloniaFil: Zapparrata, O.. Université Libre de Bruxelles; BélgicaFil: Zas, E.. Universidad de Santiago de Compostela; EspañaFil: Zavrtanik, D.. University of Nova Gorica; Eslovaquia. Experimental Particle Physics Department; EslovaquiaFil: Zavrtanik, M.. University of Nova Gorica; Eslovaquia. Experimental Particle Physics Department; EslovaquiaFil: Zehrer, L.. University of Nova Gorica; Eslovaqui

Comparison of 35 and 50 {\mu}m thin HPK UFSD after neutron irradiation up to 6*10^15 neq/cm^2

We report results from the testing of 35 {\mu}m thick Ultra-Fast Silicon Detectors (UFSD produced by Hamamatsu Photonics (HPK), Japan and the comparison of these new results to data reported before on 50 {\mu}m thick UFSD produced by HPK. The 35 {\mu}m thick sensors were irradiated with neutrons to fluences of 0, 1*10^14, 1*10^15, 3*10^15, 6*10^15 neq/cm^2. The sensors were tested pre-irradiation and post-irradiation with minimum ionizing particles (MIPs) from a 90Sr \b{eta}-source. The leakage current, capacitance, internal gain and the timing resolution were measured as a function of bias voltage at -20C and -27C. The timing resolution was extracted from the time difference with a second calibrated UFSD in coincidence, using the constant fraction method for both. Within the fluence range measured, the advantage of the 35 {\mu}m thick UFSD in timing accuracy, bias voltage and power can be established.Comment: 9 pages, 9 figures, HSTD11 Okinawa. arXiv admin note: text overlap with arXiv:1707.0496

Measurement of Aerosols at the Pierre Auger Observatory

The air fluorescence detectors (FDs) of the Pierre Auger Observatory are vital for the determination of the air shower energy scale. To compensate for variations in atmospheric conditions that affect the energy measurement, the Observatory operates an array of monitoring instruments to record hourly atmospheric conditions across the detector site, an area exceeding 3,000 square km. This paper presents results from four instruments used to characterize the aerosol component of the atmosphere: the Central Laser Facility (CLF), which provides the FDs with calibrated laser shots; the scanning backscatter lidars, which operate at three FD sites; the Aerosol Phase Function monitors (APFs), which measure the aerosol scattering cross section at two FD locations; and the Horizontal Attenuation Monitor (HAM), which measures the wavelength dependence of aerosol attenuation.Comment: Contribution to the 30th International Cosmic Ray Conference, Merida Mexico, July 2007; 4 pages, 4 figure

Radiation Hardness of Thin Low Gain Avalanche Detectors

Low Gain Avalanche Detectors (LGAD) are based on a n++-p+-p-p++ structure where an appropriate doping of the multiplication layer (p+) leads to high enough electric fields for impact ionization. Gain factors of few tens in charge significantly improve the resolution of timing measurements, particularly for thin detectors, where the timing performance was shown to be limited by Landau fluctuations. The main obstacle for their operation is the decrease of gain with irradiation, attributed to effective acceptor removal in the gain layer. Sets of thin sensors were produced by two different producers on different substrates, with different gain layer doping profiles and thicknesses (45, 50 and 80 um). Their performance in terms of gain/collected charge and leakage current was compared before and after irradiation with neutrons and pions up to the equivalent fluences of 5e15 cm-2. Transient Current Technique and charge collection measurements with LHC speed electronics were employed to characterize the detectors. The thin LGAD sensors were shown to perform much better than sensors of standard thickness (~300 um) and offer larger charge collection with respect to detectors without gain layer for fluences <2e15 cm-2. Larger initial gain prolongs the beneficial performance of LGADs. Pions were found to be more damaging than neutrons at the same equivalent fluence, while no significant difference was found between different producers. At very high fluences and bias voltages the gain appears due to deep acceptors in the bulk, hence also in thin standard detectors

Charge collection properties of irradiated depleted CMOS pixel test structures

Edge-TCT and charge collection measurements with passive test structures made in LFoundry 150 nm CMOS process on p-type substrate with initial resistivity of over 3 k$\Omega$cm are presented. Measurements were made before and after irradiation with reactor neutrons up to 2$\cdot$10$^{15}$ n$_{\mathrm{eq}}$/cm$^2$. Two sets of devices were investigated: unthinned (700 $\mu$m) with substrate biased through the implant on top and thinned (200 $\mu$m) with processed and metallised back plane. Depleted depth was estimated with Edge-TCT and collected charge was measured with $^{90}$Sr source using an external amplifier with 25 ns shaping time. Depleted depth at given bias voltage decreased with increasing neutron fluence but it was still larger than 70 $\mu$m at 250 V after the highest fluence. After irradiation much higher collected charge was measured with thinned detectors with processed back plane although the same depleted depth was observed with Edge-TCT. Most probable value of collected charge of over 5000 electrons was measured also after irradiation to 2$\cdot$10$^{15}$ n$_{\mathrm{eq}}$/cm$^2$. This is sufficient to ensure successful operation of these detectors at the outer layer of the pixel detector in the ATLAS experiment at the upgraded HL-LHC

Timing performance of small cell 3D silicon detectors

A silicon 3D detector with a single cell of 50x50 um2 was produced and evaluated for timing applications. The measurements of time resolution were performed for 90Sr electrons with dedicated electronics used also for determining time resolution of Low Gain Avalanche Detectors (LGADs). The measurements were compared to those with LGADs and also simulations. The studies showed that the dominant contribution to the timing resolution comes from the time walk originating from different induced current shapes for hits over the cell area. This contribution decreases with higher bias voltages, lower temperatures and smaller cell sizes. It is around 30 ps for a 3D detector of 50x50 um2 cell at 150 V and -20C, which is comparable to the time walk due to Landau fluctuations in LGADs. It even improves for inclined tracks and larger pads composed of multiple cells. A good agreement between measurements and simulations was obtained, thus validating the simulation results