First Results from ABRACADABRA-10cm: A Search for Low-Mass Axion Dark Matter

The presence of dark matter provides some of the most tangible evidence for the existence of physics beyond the Standard Model. One compelling dark matter candidate is the axion, a light boson that was originally postulated as a solution to another outstanding issue, the strong CP problem in QCD. ABRACADABRA is an experimental program to search for sub-$\mu$eV axion and axion-like dark matter. It searches for axion-induced modifications to Maxwell's equations with a toroidal magnet and SQUID magnetometer. This contribution will present the first results from the prototype detector, ABRACADABRA-10cm.Comment: 6 pages, 3 figures, contribution to the 2019 EW session of the 54th Rencontres de Morion

Hide and Seek. Roads, Lookouts and Directional Visibility Cones in Central Anatolia

In Cappadocia (central Turkey), routes that were only of a secondary importance during the Roman age acquired a new relevance starting from the end of the 7th century. In this framework, to what extent did the archaeological evidence match the picture recalled by the written sources? To address this question, the relationship between movement and visibility was considered and viewshed analyses were conducted from targeted and strategic spots set along the routes considered. This allowed to better understand the role and the different functions of those axes crossing Cappadocia, and to evaluate the Byzantine/Arab military strategies in central Anatolia

Water supply and demand forecasting in the Zayandeh Rud Basin, Iran

Water demandWater supplyForecastingWater useRiver basinsReservoirsIranZayandeh Rud BasinChadegan Reservoir

Electronic Structure of SiC/SiO2 by Density Functional Theory

Silicon carbide (SiC) is a promising semiconductor material with desirable properties for many applications. SiC-based electronic devices and circuits are being developed for use in high-temperature, high-power, and high-radiation conditions under which conventional semiconductors cannot function. Additionally, it has the advantage of growing a native oxide, SiO2, by simple thermal oxidation. Despite all desirable properties, SiC-based devices still face major challenges. The main problem of SiC-based devices is the great density of imperfections at the SiC/SiO2 interface, which not only degrades the device performance but also causes reliability problems coming from the extreme operating conditions. The quality of the interface affects the channel mobility of MOSFETs, which is the most critical parameter of devices. In this work a hybrid functional density functional theory framework is employed to model the (0001)4H-SiC/SiO2 abrupt interface. Using this, defect energy levels in the bandgap have been calculated through the total and projected density of states. There is experimental evidence for improvement of the quality of the interface after passivation, However the atomic mechanisms of the improvement are not yet clear., Thus, the impact of various passivations on the potential defects has also been studied. Since the interface of SiC/SiO2 is not perfectly abrupt, several atomic configurations for (0001)4H-SiC/SiO2 transition layers have also been modeled, and their effect on the bandgap, and the near interface trap density has been studied. A DFT-based Monte Carlo carrier transport simulation technique is employed to compute the average velocities, phonon-limited and ionized-impurity-limited mobilities of the most probable transition layer structures. Finally, since low frequency noise calculation is a powerful tool to diagnose quality and reliability of semiconductor devices, a DFT-based method is presented to calculate the current spectral noise density of the (0001)4H-SiC/SiO2 transition layers

De-constructing terracotta female figurines: A chalcolithic case-study

We report the results of detailed imaging studies of the inner structure of a terracotta female figurine dated to the 6th millennium BC, most probably from the Lakes region of Turkey, now kept at the Nati- onal Museum of Oriental Art \u201cGiuseppe Tucci\u201d, Rome. The figurine was investigated with advanced CT scanning, recording 966 transversal sections. Each section was stratigraphically interpreted and digitized, reconstructing in three dimensions the form and mode of application of each lump or slab under the potter\u2019s fingers. A review of the available information on the techniques of construction of prehistoric terracotta figurines in Eurasia reveals at least two diverging technical templates, here named core and dual forming processes. The structure of the investigated figurine and its operational sequence reveals a version of the dual technical template, confirming the presence and influence, at a cognitive level, of organic analogies and a possible map of the female body in the modelling process

An overview of the hydrology of the Zayandeh Rud Basin

River basins / Hydrology / Water use / Reservoirs / Water balance / Climate / Irrigation systems / Iran / Esfahan Province / Zayandeh Rud Basin / Chadegan Reservoir

Addressing fragmentation in EU mobile telecom markets. Bruegel Policy Contribution ISSUE 2015/13, July 2015

- Mobile telecommunications markets are an important part of the European Commission’s strategy for the completion of the European Union Digital Single. The use of mobile telecommunications – particularly mobile data access – is growing and becoming an increasingly important input for the economy. - The EU currently does not have a unified mobile telecommunications market. The EU compares favourably to the United States in terms of prices and connection speed, but lags behind in terms of coverage of high-speed 4G wireless connections. -Europe’s long-term goal should be to make data access easier by increasing highspeed wireless coverage while keeping prices down for users. An increase in cross-border competition could help to achieve that goal. - The Commission has two important levers to help stimulate cross-border supply:(a) ensuring competition in intra-country mobile markets in order to provide an incentive for operators to expand into other jurisdictions, and (b) reducing mobile operators’ costs of expansion into multiple EU countries. The further development of policies on international roaming and radio spectrum management will be central to this effort