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The Beam Gas Vertex (BGV) instrument is a non-invasive transverse beam profile monitor being designed as part of the High Luminosity Upgrade of the LHC (HL-LHC) at CERN. Its aim is to continuously measure bunch-by-bunch beam profiles, independent of beam intensity, throughout the LHC cycle. The primary components of the BGV monitor are a gas target and a forward tracking detector. Secondary particles emerging from inelastic beam-gas interactions are detected by the tracker. The beam profile is then inferred from the spatial distribution of reconstructed vertices of said interactions. Based on insights and conclusions acquired by a demonstrator device that was operated in the LHC during Run 2, a new design is being developed to fulfill the HL-LHC specifications. This contribution describes the status of the simulation studies being performed to evaluate the impact of design parameters on the instrument’s performance and identify gas target and tracker requirements., Proceedings of the 12th International Particle Accelerator Conference, IPAC2021, Campinas, SP, Brazil

The Beam Gas Vertex (BGV) instrument is a novel non-invasive beam profile monitor and part of the High Luminosity Upgrade of the Large Hadron Collider (LHC) at CERN. Its aim is to continuously measure emittance and transverse beam profile throughout the whole LHC cycle, which has not yet been achieved by any other single device in the machine. The BGV consists of a gas target and a forward tracking detector to reconstruct tracks and vertices resulting from beam-gas interactions. The beam profile is inferred from the spatial distribution of the vertices, making it essential to achieve a very good vertex resolution. Extensive simulation studies are being performed to provide a basis for the design of the future BGV. The goal of the study is to ascertain the requirements for the tracking detector and the gas target within the boundary conditions provided by the feasibility of integrating it into the LHC, budget and timescale. This contribution will focus on the simulations of the forward tracking detector. Based on cutting-edge track and vertex reconstruction methods, key parameter scans and their influence on the vertex resolution will be discussed., Proceedings of the 10th International Beam Instrumentation Conference, IBIC2021, Pohang, Rep. of Korea

When a relativistic charged particle travels at a short distance from the surface of dielectric material Cherenkov Diffraction Radiation (ChDR) is produced inside the dielectric. Recent observation of incoherent ChDR in the visible spectrum has opened the possibility of using this radiation for non-invasive beam size and position measurements. An experimental test to study this technique for highly directional beam position measurement has been initiated on the CLEAR facility at CERN, whilst another experimental investigation is underway at the Accelerator Test Facility 2 (ATF2) at KEK, Japan, to measure the resolution limit of ChDR for beam imaging diagnostics. This contribution presents the latest experimental results from both of these test facilities., Proceedings of the 10th Int. Particle Accelerator Conf., IPAC2019, Melbourne, Australia

We present recent results on non-invasive beam profile measurement techniques based on Diffraction Radiation (DR) and Cherenkov Diffraction Radiation (ChDR). Both methods exploit the analysis of broadband electromagnetic radiation resulting from polarization currents produced in, or at the boundary of, a medium in close proximity of a charged particle beam. To increase the resolution of DR, measurements were performed in the UV range at a wavelength of 250 nm. With such configurations, sensitivity to the beam size of a 1.2 GeV electron beam below 10 um was observed at the Accelerator Test Facility (ATF) at KEK, Japan. In the case of the ChDR, a proof of principle study was carried out at the Cornell Electron Storage Ring (CESR) where beam profiles were measured in 2017 on a 5.3 GeV positron beam. At the time of writing an experiment to measure the resolution limit of ChDR has been launched at ATF where smaller beam sizes are available. We will present experimental results and discuss the application of such techniques for future accelerators., Proceedings of the 7\textsuperscript{th} Int. Beam Instrumentation Conf., IBIC2018, Shanghai, China

During the last three years, the emission of Cherenkov Diffraction Radiation (ChDR), appearing when a relativistic charged particle moves in the vicinity of a dielectric medium, has been investigated with the aim of providing non-invasive beam diagnostics. ChDR has very interesting properties, with a large number of photons emitted in a narrow and well-defined solid angle, providing excellent conditions for detection with very little background. This contribution will present a collection of recent beam measurements performed at several facilities such as the Cornell Electron Storage Ring, the Advanced Test Facility 2 at KEK, the Diamond light source in the UK and the CLEAR test facility at CERN. Those results, complemented with simulations, suggest that the use of both incoherent and coherent emission of Cherenkov diffraction radiation could open up new beam instrumentation possibilities for relativistic charged particle beams., Proceedings of the 8th International Beam Instrumentation Conference, IBIC2019, Malmö, Sweden

Cherenkov Diffraction Radiation (ChDR), appearing when a charged particle moves in the vicinity of a dielectric medium with speed faster than the speed of light inside the medium, is a phenomenon that can be exploited for a range of non-invasive beam diagnostics. By using dielectric radiators that emit photons when in proximity to charged particle beams, one can design devices to measure beam properties such as position, direction and size. The Booster To Storage-ring (BTS) test stand at Diamond Light Source provides a 3 GeV electron beam for diagnostics research. A new vessel string has been installed to allow the BTS test stand to be used to study ChDR diagnostics applicable for both hadron and electron accelerators. This paper will discuss the commissioning of the BTS test stand, as well as exploring the initial results obtained from the ChDR monitor., Proceedings of the 8th International Beam Instrumentation Conference, IBIC2019, Malmö, Sweden

The CERN Linear Electron Accelerator for Research (CLEAR) has now finished its second year of operation, providing a testbed for new accelerator technologies and a versatile radiation source. Hosting a varied experimental program, this beamline provides a flexible test facility for users both internal and external to CERN, as well as being an excellent accelerator physics training ground. The energy can be varied between 60 and 220 MeV, bunch length between 1 and 4 ps, bunch charge in the range 10 pC to 2 nC, and number of bunches in the range 1 to 200, at a repetition rate of 0.8 to 10 Hz. The status of the facility with an overview of the recent experimental results is presented., Proceedings of the 10th Int. Particle Accelerator Conf., IPAC2019, Melbourne, Australia

A new instrument is under development for the high luminosity upgrade of the Large Hadron Collider at CERN (HL-LHC) to provide non-invasive beam size measurements throughout the acceleration cycle. The Beam Gas Vertex (BGV) detector consists of a very low pressure gas target inside the beam pipe with a series of particle tracking stations located downstream. Inelastic collisions between the beam and the gas target produce secondary particles which are detected by the tracking stations. The beam size is measured from the spatial distribution of several thousand beam-gas interaction vertices, which are identified by means of the reconstructed tracks. A demonstrator device, operated over the past 3 years, has proven the feasibility of the BGV concept and has motivated development of a fully operational device for the HL-LHC. The status of current design studies for the future instrument will be presented, with particular emphasis on potential tracking detector technologies, readout schemes, and expected performance., Proceedings of the 10th Int. Particle Accelerator Conf., IPAC2019, Melbourne, Australia

The Beam Gas Vertex detector (BGV) is an innovative beam profile monitor being developed as part of the High Luminosity LHC (HL-LHC) project at CERN. The goal is to continually measure the transverse beam size by reconstructing beam-gas interaction vertices using high precision tracking detectors. To confirm the feasibility of such a device, a demonstrator based on eight modules of scintillating fiber detectors has been constructed, installed in the LHC and operated for the past 3 years. It will be shown that using the BGV the average transverse beam size can be obtained with a statistical accuracy of better than 5µm (for a gaussian beam with a σ of 200µm). This precision is obtained with an integration time of less than one minute. In addition, the BGV measures the size of individual bunches with a statistical accuracy of better than 5% within 5 minutes. The results obtained from all the data gathered over the past 3 years will be presented and compared to measurements from other beam profile monitors. Some ideas for improvements for the final HL-LHC instrument will also be discussed., Proceedings of the 10th Int. Particle Accelerator Conf., IPAC2019, Melbourne, Australia

Based on recent measurements of incoherent Cherenkov Diffraction Radiation (ChDR) performed on the Cornell Electron Storage Ring, we present here a concept for the centering of charged particle beams when passing close to dielectric material. This would find applications as beam instrumentation in dielectric capillary tubes, typically used in novel accelerating technologies, as well as in collimators using bent crystals for high-energy, high-intensity hadron beams, such as the Large Hadron Collid-er or Future Circular Collider. As a charged particle beam travels at a distance of a few mm or less from the surface of a dielectric material, incoherent ChDR is produced inside the dielectric. The photons are emitted at a large and well-defined angle that allows their detection with a limited contribution of background light. A set of ChDR detectors distributed around a dielectric would enable both the beam position and tilt angle to be measured with a good resolution., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

This paper presents the design on the Cornell Electron Storage Ring (CESR) of an experimental set-up to meas-ure incoherent Diffraction Cherenkov Radiation (DChR) produced in a 2 cm long SiO2 radiator by a 2.1 GeV elec-tron beam. The electron beam is circulating at a distance of few mm from the edge of the radiator and the DChR photon output power is expected to be significantly higher than the diffraction radiation power emitted from a metal-lic slit of similar aperture. The radiator design and the detection set-up are presented in detail together with sim-ulations describing the expected properties of the emitted DChR in terms of light intensity and spectral bandwidth. Finally, potential applications of DChR are discussed., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

The majority of optical diagnostics currently used will not stand up to the requirements of the next generation of particle accelerators. Current methodologies need innovation to be able to reach the sub-micrometre resolution and sensitivity that will be required. One technique that has the potential to meet these requirements is optical transition radiation (OTR) imaging. A new algorithm is proposed which incorporates OTR theory, optical effects and beam distribution. This algorithm takes an existing method used for beam imaging and pushes the limits resolution beyond that normally attainable. In doing so, it can provide a reliable and economical diagnostic for future accelerators. A discussion on further applications of the algorithm is also presented., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

Optical systems are used to transfer light in beam diagnostics for a variety of imaging applications. The effect of the point spread function (PSF) of these optical systems on the resulting measurements is often approximated or misunderstood. It is imperative that the optical PSF is independently characterised, as this can severely impede the attainable resolution of a diagnostic measurement. A high quality laser and specially chosen optics have been used to generate an intense optical point source in order to accomplish such a characterisation. The point source was used to measure the PSFs of various electron-beam imaging systems. These systems incorporate a digital micro-mirror array, which was used to produce very high (>105) dynamic range images. The PSF was measured at each intermediary image plane of the optical system; enabling the origin of any perturbations to the PSF to be isolated and potentially mitigated. One of the characterised systems has been used for optical transition radiation (OTR) measurements of an electron beam at KEK-ATF2 (Tsukuba, Japan)., Proceedings of the 5th Int. Beam Instrumentation Conf., IBIC2016, Barcelona, Spain

Two major problems are the concern of this survey: first, the status of present teacher education practices in educational media conducted by state departments of public instruction, university extension divisions, and four year institutions of higher learning in the United States; and second, a comparison of the practices of these departments, divisions, and institutions during the past 20 years. The methods of two previous studies (1947 and 1957) were followed in obtaining data by questionnaire from the organizations to be studied. A comparative study was thus possible of the organization, staffing patterns, types of educational media services rendered, courses offered, and other educational services open to teachers and teachers in training. The study presents 46 tables of data obtained by the survey, as well as a bibliography. (JY)

Audiovisual instruction has become a necessary part of good teaching. This monograph separates the experiences and devices of audiovisual materials into three categories: nonprojected, projected, and audio materials and equipment. The design of schools for the use of such materials, the importance of audiovisual research, and the administration of the school audiovisual program are also discussed. (TI)

IN NOVEMBER 1959, REPRESENTATIVES OF 12 STATES IN THE ROCKY MOUNTAIN PLAINS REGION ASSEMBLED IN BOULDER, COLORADO, TO PARTICIPATED IN A 3-DAY RESEARCH SEMINAR ON TITLE VII OF THE NATIONAL DEFENSE EDUCATION ACT. (TITLE VII COVERS RESEARCH AND EXPERIMENTAL ACTIVITIES FOR MORE EFFECTIVE UTILIZATION OF TELEVISION, RADIO, MOTION PICTURES, AND RELATED MEDIA FOR EDUCATIONAL PURPOSES.) DISCUSSIONS WERE CENTERED AROUND THREE MAJOR TOPICS--(1) CONDUCTING RESEARCH IN THE MASS MEDIA, (2) DISSEMINATING RESEARCH FINDINGS, AND (3) UTILIZING EFFECTIVE PRACTICES PROVEN BY RESEARCH. RESEARCH WAS CONSIDERED AT ALL EDUCATIONAL LEVELS FROM KINDERGARTEN THROUGH ADULT EDUCATION. THIS REPORT INCLUDES THE TEXTS OF THE PROFESSIONAL DELIBERATIONS DURING THE SEMINAR AND THE INDIVIDUAL PLANS OF ACTION FORMULATED BY THE VARIOUS STATE GROUPS. (JH)

THIS REPORT IS A TRANSCRIPT OF PROCEEDINGS OF A PLANNING CONFERENCE HELD AT BOULDER, COLORADO IN SEPTEMBER 1958 FOR THE PURPOSE OF DESIGNING A LARGER CONFERENCE IN APRIL 1960. SPECIFICALLY THIS WOULD DEAL WITH MORE EFFECTIVE UTILIZATION OF TELEVISION, RADIO, MOTION PICTURES AND RELATED MEDIA FOR EDUCATIONAL PURPOSES IN THE MOUNTAIN PLAINS STATES OF ARIZONA, COLORADO, IDAHO, KANSAS, MONTANA, NEBRASKA, NEW MEXICO, NORTH DAKOTA, OKLAHOMA, SOUTH DAKOTA, TEXAS, UTAH, AND WYOMING. (LP)

In order to study the feasibility of Optical Transition (OTR) and Diffraction (ODR) Radiation based profile measurement for the future electron-positron linear colliders (ILC, CLIC) a new dedicated instrument is under development at CERN to be installed in KEK-ATF2 beam line in fall 2015. To optimize sensitivity to micron and sub-micron beam sizes, we plan to observe ODR/OTR in the visible-UV wavelength range, down to approximately 150 nm. ODR light will be produced by narrow (25-500 μm) slits with non-uniform reflectivity. To improve our knowledge on the complex pattern produced by ODR, a preparatory experiment is being conducted on the CTF3 CALIFES beam line (CERN). This device produces interferences between two OTR screens in the visible optical range with the possibility to control the distance between them, i.e. to probe the shadowing region. The new results of this OTR interference measurement will be presented, together with the latest results from the ODR run in CesrTA (Wilson lab-Cornell)., Proceedings of the 4th International Beam Instrumentation Conference, IBIC2015, Melbourne, Australia

Any imaging system requires the use of various optical components to transfer the light from the source, e.g. optical radiation generated by a charged particle beam, to the sensor. The impact of the transfer optics on the image resolution is often not well known. To improve this situation, the point spread function (PSF) of the optical system must be measured, preferably, with high dynamic range. For this purpose we have created an intense, small (~ 1 μm) point source using a high quality laser and special focusing optics; and introduced a digital micro-mirror array in the optical system to substantially increase its dynamic range. The PSFs of optical systems that are currently being developed for high resolution, high dynamic range beam imaging using optical transition and diffraction radiation are measured and compared to Zemax simulations. The goal of these studies is to systematically understand and mitigate any ill effects on the PSF due to aberrations, diffraction and misalignment of the components of the imaging system. We present the results of our measurements and simulations., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

The future electron-positon linear collider ILC is an international project aiming to follow and go forward the scientific program which is actually on-going at the Large Hadron Collider (LHC). Such a leptonic collider project implies also new concepts in particle detection to ensure a better event reconstruction : this can be achieved by using particle flow techniques. I worked for the last three years on one of those projects : the SDHCAL, a semi digital hadronic calorimeter based on glass resistive plate chambers (GRPC). This 48 layer sampling calorimeter is segmented in cells of one square centimeter for a total of 50 millions channels. To ensure such a high granularity without using any active cooling, a special care has to be taken concerning the power dissipation. To decrease the embedded front end boards consumption, a multi threshold readout (semi digital) is being used instead of an analog one. Thanks to the power pulsing mechanism using the spill structure of the collider, we have recently proven the validity of this power management scenario. After two years of GRPC detector development going along with electronic readout implementation, we were able to produce one square meter detectors. I was then mainly involved in the construction of a physical prototype built as a proof of concept. This one cubic meter detector hosts more than 400 000 channels, and weight around 10 Tons. In the last few month of my thesis I was in charge of the commissioning of this prototype on CERN beam lines. The firsts pions showers recorded during this period proved that from the technical point of view the system is working as expected.

The future electron-positon linear collider ILC is an international project aiming to follow and go forward the scientific program which is actually on-going at the Large Hadron Collider (LHC). Such a leptonic collider project implies also new concepts in particle detection to ensure a better event reconstruction : this can be achieved by using particle flow techniques. Until now, hadronic calorimeters are the bottleneck of particle detectors concepts. They are usually poorly granular and they contribute strongly to degrade the energy resolution of the reconstructed jets. In the ILC case, we aim to build highly granular calorimeters to distinguish each energy deposit. This way we can improve the energy resolution by using the most suitable detector to perform energy measurement for each particle. The CALICE collaboration federate the highly granular calorimeters R&D activities in order to distinguish the best technology for the final detector concept. I worked for the last three years on one of those projects : the SDHCAL, a semi digital hadronic calorimeter based on glass resistive plate chambers (GRPC). This 48 layer sampling calorimeter is segmented in cells of one square centimeter for a total of 50 millions channels. To ensure such a high granularity without using any active cooling, a special care has to be taken concerning the power dissipation. To decrease the embedded front end boards consumption, a multi threshold readout (semi digital) is being used instead of an analog one. Thanks to the power pulsing mechanism using the spill structure of the collider, we have recently proven the validity of this power management scenario. After two years of GRPC detector development going along with electronic readout implementation, we were able to produce one square meter detectors. I was then mainly involved in the construction of a physical prototype built as a proof of concept. This one cubic meter detector hosts more than 400 000 channels, and weight around 10 Tons. In the last few month of my thesis I was in charge of the commissioning of this prototype on CERN beam lines. The firsts pions showers recorded during this period proved that from the technical point of view the system is working as expected. The next step will be the exploitation of the recorded data to obtain the intrinsic energy resolution of the SDHCAL. Finally in the next coming years, our project will be evaluated together with the concurrent prototypes by a committee of expert in charge of selecting the most suitable option among them. The main aspects under evaluation will be : the energy resolution, the technical feasibility, and the production cost. All those aspects have been carefully taken under consideration designing the SDHCAL.; Le futur collisionneur électron-positon ILC est un projet d'envergure internationale. Il doit poursuivre le programme scientifique actuellement en cours auprès du Large Hadron Collider (LHC) lorsque celui-ci aura atteint les limites de sa sensibilité. Cet ambitieux projet d'accélérateur nécessitera également la mise en place de nouveaux concepts du point de vue de la détection. Afin d'optimiser la reconstruction des événements, une approche basée sur le suivit de particule (Particle Flow) a ainsi été adoptée. Jusqu'à aujourd'hui, les calorimètres hadroniques ont souvent représenté le point faible des expériences de physique des hautes énergies auprès de collisionneurs. En effet, leur faible granularité dégrade fortement la résolution en énergie des jets reconstruits. Dans le cas de l'ILC, il est envisagé d'utiliser des calorimètres de forte granularité de manière à distinguer clairement chaque dépôt d'énergie. Il est ainsi possible d'améliorer la résolution en énergie globale de l'expérience en utilisant le détecteur le plus approprié pour caractériser chaque particule fille issue de la collision. Les membres de la collaboration CALICE sont en charge du développement de ces calorimètres ultra granulaires. Dans ce cadre, plusieurs projets de calorimètres sont à l'étude afin de s'assurer que la technologie finalement choisie soit optimale. Durant ces trois dernières années, j'ai participé au développement de l'un de ces détecteurs : le calorimètre hadronique semi digital SDHCAL. Cet instrument utilise des chambres à plaques résistives de verre (GRPC) en tant qu'élément sensible. Ce calorimètre à échantillonnage comporte 48 plans de détection successifs séparés par de l'acier. Il est segmenté latéralement en cellules de un centimètre carré, pour un total de 50 millions de canaux. La dissipation thermique de l'électronique de lecture embarquée est un facteur clef du projet. Afin d'atteindre une forte granularité tout en évitant d'utiliser un système de refroidissement actif, nous utilisons une électronique de lecture à seuils (semi-digitale) optimisée pour une faible consommation électrique. De plus un mécanisme d'alimentation pulsée a été implémenté dans les puces de lecture. Il utilise la structure en trains des faisceaux du collisionneur pour réduire d'un facteur 100 l'énergie consommée. Ce mécanisme a été mis en oeuvre récemment par notre équipe, prouvant la validité de ce scénario. Après deux années passés à développer nos chambres de détection GRPCs, la mise au point de l'électronique de lecture ayant eut lieu en parallèle, nous avons été capables de produire nos premiers détecteurs de un mètre carré. J'ai ensuite été fortement impliqué dans la construction d'un prototype physique afin de prouver la validité de notre concept de calorimètre. Ce détecteur de un mètre cube contient plus de 400 000 canaux, et pèse presque 10 Tonnes. Durant les derniers mois de ma thèse j'ai contribué activement à la mise en fonctionnement de ce prototype auprès des lignes de faisceaux du CERN. Les premières gerbes hadroniques enregistrées durant cette période ont prouvé par leur qualité que le système fonctionne parfaitement sur le plan technologique. La prochaine étape sera l'exploitation des données enregistrées récemment pour obtenir la résolution en énergie intrinsèque du SDHCAL. Dans quelques années, ce projet ainsi que les projet concurrents seront évalués par une commission en charge de sélectionner la meilleure option pour chaque sous détecteurs de l'ILC.

The future electron-positon linear collider ILC is an international project aiming to follow and go forward the scientific program which is actually on-going at the Large Hadron Collider (LHC). Such a leptonic collider project implies also new concepts in particle detection to ensure a better event reconstruction : this can be achieved by using particle flow techniques. Until now, hadronic calorimeters are the bottleneck of particle detectors concepts. They are usually poorly granular and they contribute strongly to degrade the energy resolution of the reconstructed jets. In the ILC case, we aim to build highly granular calorimeters to distinguish each energy deposit. This way we can improve the energy resolution by using the most suitable detector to perform energy measurement for each particle. The CALICE collaboration federate the highly granular calorimeters R&D activities in order to distinguish the best technology for the final detector concept. I worked for the last three years on one of those projects : the SDHCAL, a semi digital hadronic calorimeter based on glass resistive plate chambers (GRPC). This 48 layer sampling calorimeter is segmented in cells of one square centimeter for a total of 50 millions channels. […], Le futur collisionneur électron-positon ILC est un projet d'envergure internationale. Il doit poursuivre le programme scientifique actuellement en cours auprès du Large Hadron Collider (LHC) lorsque celui-ci aura atteint les limites de sa sensibilité. Cet ambitieux projet d'accélérateur nécessitera également la mise en place de nouveaux concepts du point de vue de la détection. Afin d'optimiser la reconstruction des événements, une approche basée sur le suivit de particule (Particle Flow) a ainsi été adoptée. Jusqu'à aujourd'hui, les calorimètres hadroniques ont souvent représenté le point faible des expériences de physique des hautes énergies auprès de collisionneurs. En effet, leur faible granularité dégrade fortement la résolution en énergie des jets reconstruits. Dans le cas de l'ILC, il est envisagé d'utiliser des calorimètres de forte granularité de manière à distinguer clairement chaque dépôt d'énergie. Il est ainsi possible d'améliorer la résolution en énergie globale de l'expérience en utilisant le détecteur le plus approprié pour caractériser chaque particule fille issue de la collision. Les membres de la collaboration CALICE sont en charge du développement de ces calorimètres ultra granulaires. Dans ce cadre, plusieurs projets de calorimètres sont à l'étude afin de s'assurer que la technologie finalement choisie soit optimale. Durant ces trois dernières années, j'ai participé au développement de l'un de ces détecteurs : le calorimètre hadronique semi digital SDHCAL. Cet instrument utilise des chambres à plaques résistives de verre (GRPC) en tant qu'élément sensible. Ce calorimètre à échantillonnage comporte 48 plans de détection successifs séparés par de l'acier. Il est segmenté latéralement en cellules de un centimètre carré, pour un total de 50 millions de canaux. La dissipation thermique de l'électronique de lecture embarquée est un facteur clef du projet. […]

The International Large Detector (ILD) is a concept for a detector at the International Linear Collider, ILC. The ILC will collide electrons and positrons at energies of initially 500 GeV, upgradeable to 1 TeV. The ILC has an ambitious physics program, which will extend and complement that of the Large Hadron Collider (LHC). A hallmark of physics at the ILC is precision. The clean initial state and the comparatively benign environment of a lepton collider are ideally suited to high precision measurements. To take full advantage of the physics potential of ILC places great demands on the detector performance. The design of ILD is driven by these requirements. Excellent calorimetry and tracking are combined to obtain the best possible overall event reconstruction, including the capability to reconstruct individual particles within jets for particle ow calorimetry. This requires excellent spatial resolution for all detector systems. A highly granular calorimeter system is combined with a central tracker which stresses redundancy and efficiency. In addition, efficient reconstruction of secondary vertices and excellent momentum resolution for charged particles are essential for an ILC detector. The interaction region of the ILC is designed to host two detectors, which can be moved into the beam position with a push-pull scheme. The mechanical design of ILD and the overall integration of subdetectors takes these operational condition s into account. The International Large Detector (ILD) is a concept for a detector at the International Linear Collider, ILC. The ILC will collide electrons and positrons at energies of initially 500 GeV, upgradeable to 1 TeV. The ILC has an ambitious physics program, which will extend and complement that of the Large Hadron Collider (LHC). A hallmark of physics at the ILC is precision. The clean initial state and the comparatively benign environment of a lepton collider are ideally suited to high precision measurements. To take full advantage of the physics potential of ILC places great demands on the detector performance. The design of ILD is driven by these requirements. Excellent calorimetry and tracking are combined to obtain the best possible overall event reconstruction, including the capability to reconstruct individual particles within jets for particle ow calorimetry. This requires excellent spatial resolution for all detector systems. A highly granular calorimeter system is combined with a central tracker which stresses redundancy and efficiency. In addition, efficient reconstruction of secondary vertices and excellent momentum resolution for charged particles are essential for an ILC detector. The interaction region of the ILC is designed to host two detectors, which can be moved into the beam position with a push-pull scheme. The mechanical design of ILD and the overall integration of subdetectors takes these operational conditions into account.

Niedermolekulare polyphile Blockmoleküle, bei denen chemisch zueinander inkompatible Segmente kovalent miteinander verknüpft sind, haben sich durch ihre Fähigkeit, neuartige komplexe Mesophasenstrukturen auszubilden, in den letzten Jahren zu einem interessanten Gebiet innerhalb der Flüssigkristallforschung entwickelt. Eine wichtige Klasse bilden dabei kalamitische Bolaamphiphile, die einen flexiblen lateralen Substituenten tragen. Die in derartigen Verbindungen realisierte Kombination von Amphiphilie und Formanisotropie führt zu neuartigen Mesophasen mit außergewöhnlich komplexen Strukturen. Die vorliegende Arbeit umfasst die Synthese neuer polyphiler, niedermolekularer Blockmoleküle, bei denen an gegenüberliegenden Seiten eines bolaamphiphilen Grundgerüstes zwei Substituenten unterschiedlicher chemischer Natur fixiert wurden. Die flüssigkristallinen Eigenschaften wurden eingehend mittels Polarisationsmikroskopie, Differentialkalorimetrie und röntgenographischer Methoden charakterisiert. Um zu einem grundlegenden Verständnis des Aggregationsverhaltens dieser polyphilen Blockmoleküle zu gelangen, wurde in einem systematischen Ansatz die Größe der lateralen Substituenten als auch deren chemische Natur (Alkyl-, Perfluoralkyl- und Carbosilansegmente) variiert. Die synthetisierten Verbindungen zeigen eine große Vielfalt neuer komplexer Mesophasen. Von besonderem Interesse sind dabei die in den kolumnaren Phasen mit Zylinderstrukturen auftretende Konkurrenz von intra- und interkolumnarer Segregation, Zylinderstrukturen, die sich als mehrfarbige Parkettierung der Ebene beschreiben lassen sowie Anordnungen von Riesenzylindern mit außergewöhnlichen Formen und komplexen Überstrukturen., Polyphilic low molecular weight block molecules, in which chemically incompatible units are fixed covalently, have become a field of increased interest within liquid crystal research in the last few years due to their ability to form novel complex superstructures. An important class of such compounds represent calamitic bolaamphiphiles with flexible lateral chains. The combination of amphiphilic self-organization and shape anisotropy leads to the formation of novel mesophases with extraordinary complex structures. The subject of this work is the synthesis of novel polyphilic low molecular weight block molecules, in which two substituents of different chemical nature were fixed at opposite sides of a bolaamphiphilic structure. The liquid crystalline properties were characterized by means of polarizing microscopy, differential scanning calorimetry and X-ray scattering. To gain fundamental knowledge about the aggregation behaviour of these polyphilic block molecules the size of the lateral substituents as well as their chemical nature (alkyl, perfluoroalkyl and carbosilane segments) was changed in a systematic approach. The synthesized compounds show a wide variety of new complex mesophases. Of particular interest are: columnar phases with cylinder structures (intra- vs. intercolumnar segregation), cylinder structures which can be described as multicolour tilings and giant cylinder structures with extraordinary shapes and complex superstructures.