A simple method for the determination of the structure of ultrashort relativistic electron bunches

In this paper we propose a new method for measurements of the longitudinal profile of 100 femtosecond electron bunches for X-ray Free Electron Lasers (XFELs). The method is simply the combination of two well-known techniques, which where not previously combined to our knowledge. We use seed 10-ps 1047 nm quantum laser to produce exact optical replica of ultrafast electron bunches. The replica is generated in apparatus which consists of an input undulator (energy modulator), and the short output undulator (radiator) separated by a dispersion section. The radiation in the output undulator is excited by the electron bunch modulated at the optical wavelength and rapidly reaches 100 MW-level peak power. We then use the now-standard method of ultrashort laser pulse-shape measurement, a tandem combination of autocorrelator and spectrum (FROG -- frequency resolved optical gating). The FROG trace of the optical replica of electron bunch gives accurate and rapid electron bunch shape measurements in a way similar to a femtosecond oscilloscope. Real-time single-shot measurements of the electron bunch structure could provide significant information about physical mechanisms responsible for generation ultrashort electron bunches in bunch compressors. The big advantage of proposed technique is that it can be used to determine the slice energy spread and emittance in multishot measurements. It is possible to measure bunch structure completely, that is to measure peak current, energy spread and transverse emittance as a function of time. We illustrate with numerical examples the potential of the proposed method for electron beam diagnostics at the European X-ray FEL.Comment: 41 pages, 18 figure

The Shrinking Space of Civil Society: a Report on Trends, Responses, and the Role of Donors

Civil society is one of the main arenas of the democratization. However, in recent years the political space of civil society has become narrower and does not contribute to effective operation of civil society organisations (CSOs). Due to repression by governments, civil society organisations are encountering a series of challenges, which may extend to closing down the organisations. Civil society activists are being violently attacked, imprisoned and/or forced to emigrate. The mutual mistrust and the lack of dialogue between CSOs and government is increasing, not only in authoritarian, but also in some democratic states across the world. This study aims to promote the importance of dialogue between civil society and governments in preventing the repression of civil society. Moreover, it will investigate the nature and causes of repression of civil society, to identify trends of shrinking the space as applied by states, to explore the responses and impact of shrinking space on civil society, to determine new mechanisms and strategies for dialogue and cooperation through comparative and contrast analysis of previous researches on the topic (desk review) and case studies. The study shows that various restrictions are being applied by governments to shrink the political space of CSOs, which leads to the closing down of organisations, due to the lack of response mechanisms and capacities. On the other hand, the research identifies possible response mechanisms and support by the international community as well as providing recommendations for stakeholders to address and solve the issue. The study shows that despite democratic developments in the world, there is a need to enhance cooperation, dialogue and mutual understanding between CSOs and government to contribute to the democratisation of the countries

Genocide: Intent, Motivation and Types

Genocide is a complicated social, political and psychological phenomenon. Findings by a number of scholars show that all types of genocides are interdependent and cannot appear in pure types alone. This paper argues that the loser psychology is one major factor for developing a genocidal intent in society. Society, facing harsh realities, feels defeated and abandoned by international community and begins to look for ways out of psychological morass. Extremist passions and movements become prevalent in such societies which finally take people to insane beliefs which are based on the need to take revenge on others, to prove their superiority, to the illusion that they have found the solution for their problems: to kill others, to eliminate them from society. The paper also shows that the ultimate end of such a genocidal intent is the achievement of happiness. The capacity of society to provide its members with their wants (security, food, psychological recovery, etc) will make them happy, the failure to do so will spread gloomy environment over society. People’s desire to recover from major loses and immediately achieve happiness confuses them and leads them to false calculations, which, unfortunately, easily nest in the minds of members of society, sparking an “us-them” split the in society, which would take them to genocidal intentions

Terawatt-scale sub-10-fs laser technology - key to generation of GW-level attosecond pulses in X-ray free electron laser

We propose a technique for the production of attosecond X-ray pulses which is based on the use of X-ray SASE FEL combined with a femtosecond laser system. A few-cycle optical pulse from a Ti:sapphire laser interacts with the electron beam in a two-period undulator resonant to 800 nm wavelength and produces energy modulation within a slice of the electron bunch. Following the energy modulator the electron beam enters the X-ray undulator and produces SASE radiation. Due to energy modulation the frequency is correlated to the longitudinal position within the few-cycle-driven slice of SASE radiation pulse. The largest frequency offset corresponds to a single-spike pulse in the time domain which is confined to one half-oscillation period near the central peak electron energy. The selection of single-spike pulses is achieved by using a crystal monochromator after the X-ray undulator. Our studies show that the proposed technique is capable to produce 300 attoseconds long single pulses with GW-level output power in the 0.1 nm wavelength range, and is applicable to the European X-Ray Laser Project XFEL and the Linac Coherent Light Source at SLAC.Comment: 19 pages, 13 figure

Sociološki temelji pravne edukacije i pravne komunikacije kao mehanizma za formiranje komunikacijsko-pravne kulture pojedinaca u modernom socijalnom i kulturnom društvu

The article is devoted to the consideration of sociological foundations of legal education and legal communication as mechanisms of the formation of communicative-legal culture of a person in a modern social and cultural society. The analysis of the formation of the system of legal education in various periods of the development of a sociocultural society, starting from the XVIII century, is presented. During this period, the Slavic-Greco-Roman Academy introduced a course entitled “The teachings of justice, both spiritual and worldly”, the implementation of which involved the application of various Western legal literature in practice; this required skills to translate law books into Russian, in other words communication skills in the legal field. It also indicated that the atmosphere of spiritual crisis caused by various systematic transformations at the end of the XX century, that is, reforms, affects the level of a modern educational system. Various courses in legal education are described, during which the formation of communicative and legal culture of an individual takes place. In addition, the paper notes practical recommendations that contribute to the formation of communicative and legal culture (legal propaganda in the process of communication; legal training and education by means of language and speech; legal communication practice; communicative and legal self-education and re-education through communicative dialogue in the legal field). To summarize, there are conclusions that legal education and legal communication positively influence the formation of a person with communication and legal culture, that is, the basis for building a democratic legal country, a sociocultural society.Članak se bavi razmatranjem socioloških temelja pravne edukacije i pravne komunikacije kao mehanizama za formiranje komunikacijsko-pravne kulture pojedinaca u modernom socijalnom i kulturnom društvu. Predstavljena je analiza formiranja sustava pravne edukacije u raznim etapama razvoja socijalnog i kulturnog društva, počevši od XVIII. stoljeća. Tijekom tog je razdoblja Slavensko- grčko-rimska akademija uvela tečaj pod nazivom «Učenja o pravdi, kako duhovnoj tako i svjetovnoj», čija je provedba obuhvaćala primjenu brojne zapadne pravne literature u praksi, a to je iziskivalo vještinu prevođenja pravnih knjiga na ruski jezik, drugim riječima komunikacijske vještine na polju prava. Osim toga, ukazuje se i na činjenicu da je atmosfera duhovne krize uzrokovane sustavnim transformacijama s kraja XX. stoljeća, što znači reformama, utjecala na razinu modernog obrazovnog sustava. Nudi se opis brojnih tečajeva pravne edukacije, koji dovode do formiranja komunikacijske i pravne kulture pojedinaca. Nadalje, članak navodi praktične preporuke koje pomažu pri formiranju komunikacijske i pravne kulture (pravna promidžba u komunikacijskom procesu; pravna obuka i edukacija pomoću jezika i govora; pravna komunikacijska praksa; komunikacijska i pravna auto-edukacija i re-edukacija korištenjem komunikacijskog dijaloga na polju prava). Nakraju se navode zaključci kako pravna edukacija i pravna komunikacija imaju pozitivan utjecaj na formiranje pojedinaca koji posjeduju komunikacijsku i pravnu kulturu. To predstavlja osnovu izgradnje demokratske pravne države te socijalnog i kulturnog društva

Rotating hybrid compact stars

Starting from equations of state of nucleonic and color-superconducting quark matter and assuming a first-order phase transition between these, we construct an equation of state of stellar matter, which contains three phases: a nucleonic phase, as well as two-flavor and three-flavor color-superconducting phases of quarks. Static sequences of the corresponding hybrid stars include massive members with masses of $\sim 2 M_{\odot}$ and radii in the range of $13< R < 16$ km. We investigate the integral parameters of rapidly rotating stars and obtain evolutionary sequences that correspond to constant rest-mass stars spinning down by electromagnetic and gravitational radiation. Physically new transitional sequences are revealed that are distinguished by a phase transition from nucleonic to color-superconducting matter for some configurations that are located between the static and Keplerian limits. The snapshots of internal structure of the star, displaying the growth or shrinkage of superconducting volume as the star's spin changes, are displayed for constant rest mass stars. We further obtain evolutionary sequences of rotating supramassive compact stars and construct pre-collapse models that can be used as initial data to simulate a collapse of color-superconducting hybrid stars to a black hole.Comment: 9 pages, 9 figures; v2: minor improvements, matches published version, v3: corrected figure placemen

Armenia: the dangers of lifting lockdown when r is still above 1

Armenia lifted its lockdown in early May, when infection rates had been flatlining for three weeks. Knarik Ayvazyan (Central Bank of Armenia) and Armine Grigoryan (Fletcher School of Law and Diplomacy) use an extended SIR epidemic model to show why rates rose again in May and June