Results from a prototype chicane-based energy spectrometer for a Linear Collider

The International Linear Collider (ILC) and other proposed high energy e+e− machines aim to measure with unprecedented precision Standard Model quantities and new, not yet discovered phenomena. One of the main requirements for achieving this goal is a measurement of the incident beam energy with an uncertainty close to 10^(−4). This article presents the analysis of data from a prototype energy spectrometer commissioned in 2006-2007 in SLAC's End Station A beamline. The prototype was a 4-magnet chicane equipped with beam position monitors measuring small changes of the beam orbit through the chicane at different beam energies. A single bunch energy resolution close to 5·10^(−4) was measured, which is satisfactory for most scenarios. We also report on the operational experience with the chicane-based spectrometer and suggest ways of improving its performance

Glassy Dynamics Under Superhigh Pressure

Nearly all glass-forming liquids feature, along with the structural alpha-relaxation process, a faster secondary process (beta-relaxation), whose nature belongs to the great mysteries of glass physics. However, for some of these liquids, no well-pronounced secondary relaxation is observed. A prominent example is the archetypical glass-forming liquid glycerol. In the present work, by performing dielectric spectroscopy under superhigh pressures up to 6 GPa, we show that in glycerol a significant secondary relaxation peak appears in the dielectric loss at P > 3 GPa. We identify this beta-relaxation to be of Johari-Goldstein type and discuss its relation to the excess wing. We provide evidence for a smooth but significant increase of glass-transition temperature and fragility on increasing pressure.Comment: 5 pages, 5 figures, final version with minor changes according to referee demands and corrected Figs 1 and

BREAKING THE LAW: FROM THE HISTORY OF RUSSIAN COLONIZATION OF THE STEPPE IN THE XVII CENTURY

The Russian colonization of the Steppe was connected with a variety of specific points that became apparent in special psychology of the local population. The article studies an incident that happened in a small fortress at the southern frontier of Russia on June 12, 1648. The local residents seized power and executed collectively a man who was engaged in usury and speculation. They were sure that execution, though illegal, was in the public interest. This case shows some features of Russian social organization where the collective interests were put above the law and legal rights. So we see an interesting incident in history. It reflected the specificity of local community consciousness which put the interests of the collective above laws and regulations. For the residents of the ostrog the decision of people's court had greater legitimacy than the current legislation. It is interesting, that Chubulov was not just murdered by his debtors. This improvised «execution» was preceded by many things: the gathering, the prosecution, the trial. All events were accompanied by drumbeats. Even the execution of Chubulov was collective: all elected representatives of the people («mir») took part in it. This case shows that for the population of the southern Russian frontier collective public interests were above private ones. Surely, this factor contributed to the success of military colonization of the steppe spaces by Russian population. To violate the law for the benefit of social justice was a valid action for the residents of Russian frontier

Principal Component Analysis of Cavity Beam Position Monitor Signals

Model-independent analysis (MIA) methods are generally useful for analysing complex systems in which relationships between the observables are non-trivial and noise is present. Principle Component Analysis (PCA) is one of MIA methods allowing to isolate components in the input data graded to their contribution to the variability of the data. In this publication we show how the PCA can be applied to digitised signals obtained from a cavity beam position monitor (CBPM) system on the example of a 3-cavity test system installed at the Accelerator Test Facility 2 (ATF2) at KEK in Japan. We demonstrate that the PCA based method can be used to extract beam position information, and matches conventional techniques in terms of performance, while requiring considerably less settings and data for calibration

Cases of Peasants in the South of Russia in the 20s of the 17th Century

Introduction. Among the materials of the Belgorod Stol of the Russian State Archive of Ancient Acts (RGADA), there is an extensive set of documents related to disputes over peasants who fled to the South of Russia from uyezds of other regions of the state. These are “cases of peasants” which were created in the 1620s. They are an important episode of the overall picture of the economic development of Southern Russia in the 17th century. These documents are of great interest for the study of the Russian peasantry. Methods. The author uses the problem-historical method and traditional methods of working with historical sources. The focus of the article is an attempt to comprehend this vast complex of records management materials. These important materials are connected with the peasant issue in uyezds of Southern Russia in the 1620s. The question is how peasants, who did not have freedom, could move to the South. Unfortunately, this topic was hardly a subject of study in historiography. However, historian Novoselsky showed the importance of studying “cases of peasants”. In the course of the article, the author shows that peasants did not have legal grounds for the resettlement to the southern outskirts. In the last two decades of the 16th century, peasants were attached to the land. This is a wellknown and proven fact. However, in the Time of Troubles, many peasant families fled to the South. It was a time of anarchy. In the 1620s, the flight of peasants continued and was numerous. This triggered the emergence of “cases of peasants”. The author has studied 58 cases of this kind. Results. The study of these documents shows that the governmental policy regarding the flight of peasants was not harsh. The state allowed the possibility of the flight of peasants. The authorities did not consider landowners who accepted fugitives to be lawbreakers. The rules prohibiting the transfer of peasants began to act only if a landowner found his peasant and filed a lawsuit about his return

Pressure-induced amorphization, crystal-crystal transformations and the memory glass effect in interacting particles in two dimensions

We study a model of interacting particles in two dimensions to address the relation between crystal-crystal transformations and pressure-induced amorphization. On increasing pressure at very low temperature, our model undergoes a martensitic crystal-crystal transformation. The characteristics of the resulting polycrystalline structure depend on defect density, compression rate, and nucleation and growth barriers. We find two different limiting cases. In one of them the martensite crystals, once nucleated, grow easily perpendicularly to the invariant interface, and the final structure contains large crystals of the different martensite variants. Upon decompression almost every atom returns to its original position, and the original crystal is fully recovered. In the second limiting case, after nucleation the growth of martensite crystals is inhibited by energetic barriers. The final morphology in this case is that of a polycrystal with a very small crystal size. This may be taken to be amorphous if we have only access (as experimentally may be the case) to the angularly averaged structure factor. However, this `X-ray amorphous' material is anisotropic, and this shows up upon decompression, when it recovers the original crystalline structure with an orientation correlated with the one it had prior to compression. The memory effect of this X-ray amorphous material is a natural consequence of the memory effect associated to the underlying martensitic transformation. We suggest that this kind of mechanism is present in many of the experimental observations of the memory glass effect, in which a crystal with the original orientation is recovered from an apparently amorphous sample when pressure is released.Comment: 13 pages, 13 figures, to be published in Phys. Rev.