Manipulation of the Bitcoin market: an agent-based study

Fraudulent actions of a trader or a group of traders can cause substantial disturbance to the market, both directly influencing the price of an asset or indirectly by misinforming other market participants. Such behavior can be a source of systemic risk and increasing distrust for the market participants, consequences that call for viable countermeasures. Building on the foundations provided by the extant literature, this study aims to design an agent-based market model capable of reproducing the behavior of the Bitcoin market during the time of an alleged Bitcoin price manipulation that occurred between 2017 and early 2018. The model includes the mechanisms of a limit order book market and several agents associated with different trading strategies, including a fraudulent agent, initialized from empirical data and who performs market manipulation. The model is validated with respect to the Bitcoin price as well as the amount of Bitcoins obtained by the fraudulent agent and the traded volume. Simulation results provide a satisfactory fit to historical data. Several price dips and volume anomalies are explained by the actions of the fraudulent trader, completing the known body of evidence extracted from blockchain activity. The model suggests that the presence of the fraudulent agent was essential to obtain Bitcoin price development in the given time period; without this agent, it would have been very unlikely that the price had reached the heights as it did in late 2017. The insights gained from the model, especially the connection between liquidity and manipulation efficiency, unfold a discussion on how to prevent illicit behavior

SEU Robustness, Total Dose Radiation Hardness and Analogue Performance of the Beetle Chip

The Beetle is a 128 channel readout chip for silicon strip detectors in LHCb. In addition to the pipelined readout path known from the RD20 architecture which can be used either in analogue or binary mode, the Beetle features an additional prompt binary readout path, used for the LHCb pile-up veto counters and a triple-redundant layout of the control logic. It is manufactured in commercial 0.25 µm CMOS technology using radiation hard design techniques. In addition to a total dose irradiation with X-rays, an SEU irradiation test with 65 MeV protons was performed with Beetle1.3. The results of this test are presented together with new results from the Beetle versions 1.3, 1.4 and 1.5, which were submitted in the Beetle ER engineering run in May 2004

Performance of the Beetle readout chip for LHCb

Beetle is a 128-channel readout chip, which will be used in the silicon vertex detector, the pile-up veto counters and the silicon tracker of the LHCb experiment at CERN. A further application of the Beetle chip is the readout of the LHCb RICH, in case it is equipped with multi-anode PMTs. The scope of this paper is the design changes leading to the latest version 1.3 of the Beetle readout chip. In addition, measurements on earlier versions and simulation results driving these changes are shown