Effect of the superconducting wiggler on the DELSY beam dynamics

The project DELSY is being under development at JINR, Dubna, Russia. This synchrotron radiation source is dedicated to the investigation on condensed matter physics, atomic physics, biology, medicine, chemistry, micromechanics, lithography and others. The storage ring DELSY is an electron storage ring with the beam energy 1.2 GeV and 4 straight sections to accommodate accelerator equipment and insertion devices. One of the straight sections is intended for a 10 T superconducting wiggler (wavelength shifter) and one for the undulator with 150 periods and a magnetic field of 0.75 T. The wiggler will influence many aspects of beam dynamics: linear motion, dynamic aperture, emittance, damping times etc. The problem is rather serious for the DELSY machine because the energy of the electron beam is small while the wiggler's magnetic field is strong. In this paper we consider two models of the wiggler's magnetic field with and without the focusing caused by the sextupolar field of the wiggler as we need to develop the requirements to the wiggler design. We study the influence of the 10 T wiggler on the beam dynamics in the DELSY storage ring and propose a possible scheme to cure it. The combined work of the insertion device is presented too.Comment: 17 pages, submitted to journal NIM

High-Temperature Electrochemical Refining of Secondary Lead

The present chapter is devoted to the analysis of the obtained data on the high-temperature electrolytic production of high-purity lead from secondary lead in chloride melts. Kinetic parameters of electrode reactions were calculated, and the sequences of the metal dissolution from the double lead-antimony (Pb-Sb), lead-bismuth (Pb-Bi), and antimony-bismuth (Sb-Bi) alloys were determined. A long-term electrolysis of the antimony (battery scrap), bismuth (lead-bismuth), and lead-containing raw materials in the electrolytic cell of original construction with a porous ceramic diaphragm impregnated with the eutectic KCl-PbCl2 chloride electrolyte was performed. The anode lead alloy, containing 57.0 wt% of antimony and 36.0 wt% of bismuth, and cathode grade lead were obtained as a result of the electrolysis. The values of lead, antimony, and bismuth separation coefficients were calculated according to the values of the equilibrium potentials of the Pb-Sb, Pb-Bi, and Sb-Bi alloys. The values of separation coefficients were found to be 6.5·106–1.5·108 for a single stage at the lead extraction from the Pb-Sb and Pb-Bi alloys, which proves the possibility of a highly effective lead extraction. The value of Sb-Bi alloy separation coefficient ranges from 5.5 to 6.5, which testifies the complexity and low effectiveness of the separation process. An electrolytic refining of lead-bismuth and secondary lead, obtained from the battery scrap, was performed

Passive and hybrid mode locking in multi-section terahertz quantum cascade lasers

It is believed that passive mode locking is virtually impossible in quantum cascade lasers (QCLs) because of too fast carrier relaxation time. Here, we revisit this possibility and theoretically show that stable mode locking and pulse durations in the few cycle regime at terahertz (THz) frequencies are possible in suitably engineered bound-to-continuum QCLs. We achieve this by utilizing a multi-section cavity geometry with alternating gain and absorber sections. The critical ingredients are the very strong coupling of the absorber to both field and environment as well as a fast absorber carrier recovery dynamics. Under these conditions, even if the gain relaxation time is several times faster than the cavity round trip time, generation of few-cycle pulses is feasible. We investigate three different approaches for ultrashort pulse generation via THz quantum cascade lasers, namely passive, hybrid and colliding pulse mode locking

Molecular Dipolar Crystals as High Fidelity Quantum Memory for Hybrid Quantum Computing

We study collective excitations of rotational and spin states of an ensemble of polar molecules, which are prepared in a dipolar crystalline phase, as a candidate for a high fidelity quantum memory. While dipolar crystals are formed in the high density limit of cold clouds of polar molecules under 1D and 2D trapping conditions, the crystalline structure protects the molecular qubits from detrimental effects of short range collisions. We calculate the lifetime of the quantum memory by identifying the dominant decoherence mechanisms, and estimate their effects on gate operations, when a molecular ensemble qubit is transferred to a superconducting strip line cavity (circuit QED). In the case rotational excitations coupled by dipole-dipole interactions we identify phonons as the main limitation of the life time of qubits. We study specific setups and conditions, where the coupling to the phonon modes is minimized. Detailed results are presented for a 1D dipolar chain

Quantum phase transition in a two-dimensional system of dipoles

The ground-state phase diagram of a two-dimensional Bose system with dipole-dipole interactions is studied by means of quantum Monte Carlo technique. Our calculation predicts a quantum phase transition from gas to solid phase when the density increases. In the gas phase the condensate fraction is calculated as a function of the density. Using Feynman approximation, the collective excitation branch is studied and appearance of a roton minimum is observed. Results of the static structure factor at both sides of the gas-solid phase are also presented. The Lindeman ratio at the transition point comes to be $\gamma = 0.230(6)$. The condensate fraction in the gas phase is estimated as a function of the density.Comment: 4 figures v.3 One citation added, updated Fig.4. Minor changes following referee's and editor's comment

Electrode processes during the electrorefiniment of lead in the KCl-PbCl2-PbO melt

The influence of PbO addition on current efficiency during the electrorefinement of lead in the KCl-PbCl2-PbO melt was investigated. It was shown that with PbO concentration in the KCl-PbCl2 eqiumolar mixture increasing, the current efficiency of lead decreases. Electrode processes mechanism is proposed

Estimation of the activity of lead in the binary Pb-Sb and Pb-Bi systems

The activity of lead in its alloys with bismuth and antimony is estimated by the least squares method and interval analysis. The interval method of processing the experimental results is shown to calculate the reliable ranges of the estimated parameters in the dependences of thermodynamic functions and the actual level of the total measurement errors. © 2013 Pleiades Publishing, Ltd

Evolution of the Genre of Criticism in the Network Space

Жанры журналистики вынуждены подстраиваться под особенности интернета. Это касается критических жанров в том числе, потому что рецензии и обзоры классических форматов теряют популярность. Профессиональные критики склонны обвинять аудиторию в снижении уровня культуры и клиповом мышлении. Также они отмечают дефицит кадров. Однако, учитывая популярность культурных блогеров-любителей, проблема может заключаться в нежелании профессионалов осваивать новые форматы.The genres of journalism are forced to adapt to the special aspects of the Internet. This also applies to critical genres, because classical format of reviews is losing popularity. Professional critics tend to blame the audience for lowering their culture level and for mosaic thinking. They also note a staff shortage in the criticism sphere. However, given the popularity of cultural amateur bloggers, the problem of professional critics may be in a reluctance to learn new formats

The Role of Journalism in The Formation of Video Game Culture in Russia

Статья поступила в редакцию 27.12.2022 г.Статья посвящена игровой журналистике и ее роли в формировании видеоигровой культуры в России. На историческом материале раскрывается проблема неполноты информации на эту тему. Предлагается собственный вариант определения и описания этапов развития гейм-периодики в России с 1970-х гг. до наших дней. Намечаются ближайшие перспективы этого развития. Рассматривается влияние гейм-журналистики на игровую культуру.The article is devoted to game journalism and its role in the formation of video game culture in Russia. The historical material reveals the problem of incompleteness of information on this topic. We propose our own version of the definition and description of the stages of development of game periodicals in Russia from the 1970s to the present day. The immediate prospects of this development are outlined. The influence of game journalism on game culture is considered

Politicization of Foreign Video Game Journalism on the Example of Materials about Atomic Heart

Зарубежная видеоигровая журналистика отличается высоким уровнем профессионализма авторов. Отечественная, в то же время, существует в основном благодаря любителям. Однако примечателен момент сильной политизированности зарубежной видеоигровой журналистики, которая порой мешает объективно оценивать проекты. Отечественная же игровая журналистика лишена такой проблемы. В работе проводится анализ, демонстрирующий распространенность явления на примере Atomic Heart.International video game journalism is distinguished by a high level of professionalism of the authors. Russian, at the same time, exists mainly thanks to amateurs. However, the strong politicization of non-Russian video game journalism is noteworthy, which sometimes makes it difficult to objectively evaluate projects. Russian game journalism 8 is devoid of such a problem. The paper provides an analysis demonstrating the prevalence of the phenomenon on the example of Atomic Heart