Input Comparison of Radiogenic Neutron Estimates for Ultra-low Background Experiments

Ultra-low-background experiments address some of the most important open questions in particle physics, cosmology and astrophysics: the nature of dark matter, whether the neutrino is its own antiparticle, and does the proton decay. These rare event searches require well-understood and minimized backgrounds. Simulations are used to understand backgrounds caused by naturally occurring radioactivity in the rock and in every piece of shielding and detector material used in these experiments. Most important are processes like spontaneous fission and ({\alpha},n) reactions in material close to the detectors that can produce neutrons. A comparison study between two dedicated software packages is detailed. The cross section libraries, neutron yields, and spectra from the Mei-Zhang-Hime and the SOURCES-4A codes are presented. The resultant yields and spectra are used as inputs to direct dark matter detector toy models in GEANT4, to study the impact of their differences on background estimates and fits. Although differences in neutron yield calculations up to 50% were seen, there was no systematic difference between the Mei-Hime-Zhang and SOURCES-4A results. Neutron propagation simulations smooth differences in spectral shape and yield, and both tools were found to meet the broad requirements of the low-background community

Visible and infrared photocurrent enhancement in a graphene-silicon Schottky photodetector through surface-states and electric field engineering

The design of efficient graphene-silicon (GSi) Schottky junction photodetectors requires detailed understanding of the spatial origin of the photoresponse. Scanning-photocurrent-microscopy (SPM) studies have been carried out in the visible wavelengths regions only, in which the response due to silicon is dominant. Here we present comparative SPM studies in the visible ($\lambda$ = 633nm) and infrared ($\lambda$ = 1550nm) wavelength regions for a number of GSi Schottky junction photodetector architectures, revealing the photoresponse mechanisms for silicon and graphene dominated responses, respectively, and demonstrating the influence of electrostatics on the device performance. Local electric field enhancement at the graphene edges leads to a more than ten-fold increased photoresponse compared to the bulk of the graphene-silicon junction. Intentional design and patterning of such graphene edges is demonstrated as an efficient strategy to increase the overall photoresponse of the devices. Complementary simulations and modeling illuminate observed effects and highlight the importance of considering graphene's shape and pattern and device geometry in the device design

Analisis Pengaruh Customer Relationship Management, Persepsi Harga, dan Kualitas Pelayanan terhadap Loyalitas Pelanggan Kendaraan Niaga Merek Hino

This research aims to examine and Analysis the Effect of Customer Relationship Management, Price Perception, and Quality of Service to Customer Loyalty Vehicle Logistic Brand Hino that became the object of research. The reaserch design used is quantitative and explanatory research type of survey methods. Data was collected using questionnaires to 105 respondents, the sampling technique used is online survey via customer emails as. The method of analysis is SPSS. The result of the research showed that customer relationship management has a positively and significant customer loyalty vehicle logistic, price perception have positiv and effect significant customer loyalty vehicle logistic, and quality of service positive and significant influence to customer loyalty vehicle logisti

A Power Quality Improvement for Microgrid Inverter Operated in Grid Connected and Grid Disconnected Modes

The renewable energy based distributed generators (DGs) will plays a dominant role in electricity production. A micro grid consists of clusters of load and distributed generators that operate as a single controllable system. The interconnection of the DG to the utility/grid through power electronic converters has raised concern about safe operation and protection of the equipments. The main objective of this paper is too focused on the power quality improvement in micro grid. In the distributed power system, the increased infiltration of nonlinear loads and power electronic interfaced distribution generation systems creates power quality issues such as voltage unbalance, frequency regulation and harmonic elimination

Muon-induced neutrons do not explain the DAMA data

We present an accurate model of the muon-induced background in the DAMA/LIBRA experiment. Our work challenges proposed mechanisms which seek to explain the observed DAMA signal modulation with muon-induced backgrounds. Muon generation and transport are performed using the MUSIC/MUSUN code, and subsequent interactions in the vicinity of the DAMA detector cavern are simulated with Geant4. We estimate the total muon-induced neutron flux in the detector cavern to be $\Phi_n^\nu = 1.0\times10^{-9}$ cm$^{-2}$ s$^{-1}$. We predict $3.49\times10^{-5}$ counts/day/kg/keV, which accounts for less than $0.3\%$ of the DAMA signal modulation amplitude.Comment: 6 pages, 4 figures, accepted for publication in PR

Fasilitas Edukasi dan Galeri Komunitas Fotografi di Jember

Fasilitas Edukasi dan Galeri Komunitas Fotografi di Jember ini merupakan sebuah fasilitas yang mewadahi kegiatan belajar mengajar, saling berdiskusi dan berkumpul serta tempat memamerkan hasil karya yang berhubungan dengan fotografi di Jember. Fasilitas ini ada karena kurang perhatiannya Pemerintah Kabupaten Jember terhadap keberadaan para pecinta fotografi, serta sudah semakin banyaknya masyarakat pecinta fotografi maupun masyarakat yang ingin belajar lebih dalam tentang fotografi. Pemilihan tapak berada di pusat kota Jember yang berada di dekat kampus dan sekolah. Untuk bentuk dan pendalaman diambil dari bagian kamera, yaitu diafragma lensa yang bersegmen. Dalam proses fotografi, untuk mendapatkan foto yang baik membutuhkan cahaya yang masuk melalui diafragma kamera. Oleh karena itu pendekatan yang diambil adalah pendekatan simbolik yang ditransformasikan kedalam bentuk bangunan. Bentuk bangunan ini merupakan transformasi dari bentuk diafragma kamera dimana diafragma kamera berkaitan juga dengan banyak atau sedikit cahaya yang masuk

Multi-Component Dark Matter Systems and Their Observation Prospects

Conversions and semi-annihilations of dark matter (DM) particles in addition to the standard DM annihilations are considered in a three-component DM system. We find that the relic abundance of DM can be very sensitive to these non-standard DM annihilation processes, which has been recently found for two-component DM systems. To consider a concrete model of a three-component DM system, we extend the radiative seesaw model of Ma by adding a Majorana fermion \chi and a real scalar boson \phi, to obtain a Z_2 \times Z'_2 DM stabilizing symmetry, where we assume that the DM particles are the inert Higgs boson, \chi and \phi. It is shown how the allowed parameter space, obtained previously in the absence of \chi and \phi, changes. The semi-annihilation process in this model produces monochromatic neutrinos. The observation rate of these monochromatic neutrinos from the Sun at IceCube is estimated. Observations of high energy monochromatic neutrinos from the Sun may indicate a multi-component DM system.Comment: 27 pages, 11 figure