120319912
A large-area magnetic spectrometer for the study of high-energy neutrino interactions
Abstract We describe the design, construction, and performance of a large solid iron magnetic spectrometer which has been used to i dentify and measure the momentum of muons produced by interactions of neutrinos with nucleons. The rms momentum resolution varies from 10 to 15 percent between 5 and 150 GeV/ c .
38997255
Prototype detector for ultrahigh energy neutrino detection
Abstract Necessary technical experience is being gained from successful construction and deployment of current prototype detectors to search for UHE neutrinos in Antarctica, Lake Baikal in Russia, and the Mediterranean. The prototype detectors have also the important central purpose of determining whether or not UHE neutrinos do in fact exist in nature by observation of at least a few UHE neutrino-induced leptons with properties that are not consistent with expected backgrounds. We discuss here the criteria for a prototype detector to accomplish that purpose in a convincing way even if the UHE neutrino flux is substantially lower than predicted at present.
123899161
NEUTRINOS AND MUONS IN AREA 1.
121246612
Scaling-variable distributions in high-energy inelastic neutrino interactions
118973535
Some Recent Advances in Neutrino Physics
One answer to questions concerning the subject matter of elementary particle physics and its position within the physical sciences is that particle physics is the study of creation. To justify this idea, at least in part, consider the “big bang” model of creation of the universe. In that model the primeval fireball involved very high temperatures, estimated to be greater than 1011 degrees Kelvin (°K), which is to be compared with the interior temperature of the sun at about 107 degrees Kelvin. We believe the sun to be a nuclear furnace, generating its energy by individual nuclear interactions in the million electron volt (MeV) energy range. In the “big bang” the energies involved in the individual particle interactions would have been more than 104 times larger than in the sun, and thus in the tens of giga-electron volts (GeV). This is precisely the energy region of present-day high energy or elementary particle physics laboratory experiments. In this sense, then, laboratory experiments that study, even indirectly, lepton-lepton scattering or quark-quark interactions are revisiting creation.
118712243
Comments on the letter «Limits on the electromagnetic production of heavy leptons»
118409646
Superfluidity of hadronic matter
SummaryThe mesons in the nucleon are associated with a Bose system with an energy excitation spectrum ε(p), wherep is the corresponding momentum. This spectrum can be investigated by studying the nucleon recoil in one-meson production processes. It turns out that
$$\mathop {\lim }\limits_{p \to 0} (\varepsilon /p) \ne 0$$
. This is the Landau criterion for superfluidity. Herefrom we infer that hadronic matter is superfluid. Possible manifestations of this phenomenon in strong interactions are a bootstrap relation between the masses of mesonic and baryonic resonances, the shift of the δ-resonance in nuclei, the existence of a maximum resonance mass equivalent to an ionization point and the existence of a critical temperature of hadronic matter instead of a maximum temperature.RiassuntoI mesoni nel nucleone sono associati per mezzo di un sistema di bose con uno spettro di energie di eccitazione ε(p), dovep è l'impulso corrispondente. Si può analizzare questo spettro studiando il rinculo del nucleone nei processi di produzione di un mesone. Risulta che
$$\mathop {\lim }\limits_{p \to 0} (\varepsilon /p) \ne 0$$
. Questo è il criterio di landau per la superfluidità. Da ciò si inferisce che la materia adronica è superfluida. Possibili manifestazioni di questo fenomeno nelle interazioni forti sono una relazione di bootstrap fra le masse delle risonanze mesoniche e barioniche, lo spostamento della risonanza δ nei nuclei, l'esistenza di una massa massima della risonanza equivalente ad un punto di ionizzazione e l'esistenza di una temperatura critica della materia adronica invece di una temperatura massima.РезюмеМезоны в нуклоне связываутся с Гозе-системой с энергетическим спектром возбуждения ε(p), гдеp есть соответствующии импульс. Этот спектр может быть исследован посредством изучения отдачи нуклона в процессе рождения одного пиона. Оказывается, что
$$\mathop {\lim }\limits_{p \to 0} (\varepsilon /p) \ne 0$$
. Это представляет критерий Ландау для сверхтекучести, из которого мы делаем вывод, что адронное вещество является сверхтекучим. Возможные проявления этого явления в сильных взаимодействиях представляют: соотношения бутстрепа между массами мезонных и барионных резонансов, сдвиг δ резонанса в ядрах, существование резонансной массы, эквивалентной точке ионизации, и существование критической температуры адронного вещества вместо максимальной темпатуры.
122119912
Kirchhoff's theorem and the Casimir effect
Kirchhoff's thermodynamically based classical theorem (the energy density of the radiation in equilibrium is a function of T only) is used to obtain a relation relevant to study of the Casimir effect. We use it to obtain the zero-temperature Casimir energy without recourse to regularizaion. The intimate connection between the zero-point energy and the thermal Bose occupancy expression noted by Einstein and Stern at the turn of the century is invoked to account for the results.
119480279
Generalized coherent states are unique Bell states of quantum systems with Lie-group symmetries
Entanglement is the main quantum mechanical feature that distinguishes between quantum and classical physics. A state of a quantum system, consisting of two subsystems, is called entangled if it cannot be represented as a direct product of states of the subsystems. The nonclassicality of such a situation is expressed mathematically by the violation of Bell’s inequality @1,2#. More specifically, let us consider a quantum system A ~e.g., a mode of the quantized radiation field or a spin-j particle!, which is split or decays into two subsystems B and C @3#. A pure quantum state that upon splitting will not violate Bell’s inequality ~i.e., a quantum state that possesses the basic attribute of classical physics ! has been called the Bell state @4#. It has been proven @4‐6# that a state that factorizes upon splitting into a direct product cannot violate Bell’s inequality, while a state that gives rise to an entangled ~i.e., nonproduct! state can always, by a suitable choice of local apparatus, be made to violate the inequality. Therefore the Bell state of the system A must factorize upon splitting into the direct product of states of the subsystems.
8636737
The universal sampling ADC readout system of the COMPASS experiment
The COMPASS experiment (COmpact Muon Proton Apparatus for Structure and Spectroscopy) is a fixed target experiment located at the CERN Super Proton Synchrotron. The physics program is focused on the study of hadron structure and hadron spectroscopy with high intensity muon and hadron beams, up to 160 GeV/c for muons and 190 GeV/c for hadrons respectively. To allow the tracking of charged particles with very low and as well very high momentum, COMPASS comprises two magnetic spectrometer stages extending to a total length of 60 m. From the data acquisition point of view, about 200000 analog detector channels have to be read along the complete experiment. Depending on the detector signal characteristics and the number of channels, this task is realized by frontend electronics using either dedicated ASICs and/or sampling analog-to-digital (ADC) or time-to-digital (TDC) components. The sampling ADC based readout system of the COMPASS experiment comprises today over 127k channels equipped with the APV25 frontend ASIC and 5728 direct sampling channels. An important feature from the beginning was the combination of data transfer, clock and trigger distribution and configuration access within a standardized serial interface between the different ADC modules and the first stage of data concentrator modules. By choosing between a copper or fiber realization for this interface, either a low cost interconnect or a link with galvanic decoupling can be realized. The ongoing development of the sampling ADC electronics is focused on the migration toward the Advanced Telecom Computing Architecture (ATCA) crate standard, to overcome the backplane bandwidth limitations in VME systems. In addition, the ATCA standard provides better cooling and monitoring capabilities. To simplify the transition to ATCA, the MSADC module was already realized as a mezzanine card, which can be mounted on an ATCA based carrier card as well. In addition, the MSADC card fits also to the MicroTCA form factor, which allows to provide a handy building block for laboratory based data acquisition systems.
122239911
Maximumvs. Critical temperature in a superfluid approach to strong interactions