Quality of ALICE SSD modules revealed by electrical tests

ALICE (A Large Ion Collider Experiment) is an experiment at CERN (European Organization for Nuclear Research), where a heavy-ion detector is dedicated to exploit the unique physics potential of nucleus-nucleus interactions at LHC (Large Hadron Collider) energies. In a part of that project, 716 so-called type V4 modules were assembles in Detector Laboratory of Helsinki Institute of Physics during the years 2004 - 2006. Altogether over a million detector strips has made this project the most massive particle detector project in the science history of Finland. One ALICE SSD module consists of a double-sided silicon sensor, two hybrids containing 12 HAL25 front end readout chips and some passive components, such has resistors and capacitors. The components are connected together by TAB (Tape Automated Bonding) microcables. The components of the modules were tested in every assembly phase with comparable electrical tests to ensure the reliable functioning of the detectors and to plot the possible problems. The components were accepted or rejected by the limits confirmed by ALICE collaboration. This study is concentrating on the test results of framed chips, hybrids and modules. The total yield of the framed chips is 90.8%, hybrids 96.1% and modules 86.2%. The individual test results have been investigated in the light of the known error sources that appeared during the project. After solving the problems appearing during the learning-curve of the project, the material problems, such as defected chip cables and sensors, seemed to induce the most of the assembly rejections. The problems were typically seen in tests as too many individual channel failures. Instead, the bonding failures rarely caused the rejections of any component. One sensor type among three different sensor manufacturers has proven to have lower quality than the others. The sensors of this manufacturer are very noisy and their depletion voltage are usually outside of the specification given to the manufacturers. Reaching 95% assembling yield during the module production demonstrates that the assembly process has been highly successful.

Supistamista, rationalisointia vai kehittämistä? : Valtiovarainministeriön järjestelyosaston järjestämän henkilöstökoulutus- ja tutkimustoiminnan rakentuminen osaksi valtionhallintoa vuosina 1943-1971

The study examines the personnel training and research activities carried out by the Organization and Methods Division of the Ministry of Finance and their becoming a part and parcel of the state administration in 1943-1971. The study is a combination of institutional and ideological historical research in recent history on adult education, using a constructionist approach. Material salient to the study comes from the files of the Organization and Methods Division in the National Archives, parliamentary documents, committee reports, and the magazines. The concentrated training and research activities arranged by the Organization and Methods Division, became a part and parcel of the state administration in the midst of controversial challenges and opportunities. They served to solve social problems which beset the state administration as well as contextual challenges besetting rationalization measures, and organizational challenges. The activities were also affected by a dependence on decision-makers, administrative units, and civil servants organizations, by different views on rationalization and the holistic nature of reforms, as well as by the formal theories that served as resources. It chose long-term projects which extended to the political decision-makers and administrative units turf, and which were intended to reform the structures of the state administration and to rationalize the practices of the administrative units. The crucial questions emerged in opposite pairs (a constitutional state vs. the ideology of an administratively governed state, a system of national boards vs. a system of government through ministries, efficiency of work vs. pleasantness of work, centralized vs. decentralized rationalization activities) which were not solvable problems but impossible questions with no ultimate answers. The aim and intent of the rationalization of the state administration (the reform of the central, provincial, and local governments) was to facilitate integrated management and to render a greater amount of work by approaching management procedures scientifically and by clarifying administrative instances and their respon-sibilities in regards to each other. The means resorted to were organizational studies and committee work. In the rationalization of office work and finance control, the idea was to effect savings in administrative costs and to pare down those costs as well as to rationalize and heighten those functions by developing the institution of work study practitioners in order to coordinate employer and employee relationships and benefits (the training of work study practitioners, work study, and a two-tier work study practitioner organization). A major part of the training meant teaching and implementing leadership skills in practice, which, in turn, meant that the learning environment was the genuine work community and efforts to change it. In office rationalization, the solution to regulate the relations between the employer and the employees was the co-existence of the technical and biological rationalization and the human resource administration and the accounting and planning systems at the turn of the 1960s and 1970s. The former were based on the school of scientific management and human relations, the latter on system thinking, which was a combination of the former two. In the rationalization of the state administration, efforts were made to find solutions to stabilize management ideologies and to arrange the relationships of administrative systems in administrative science - among other things, in the Hoover Committee and the Simon decision making theory, and, in the 1960s, in system thinking. Despite the development-related vocabulary, the practical work was advanced rationalization. It was said that the practical activities of both the state administration and the administrative units depended on professional managers who saw to production results and human relations. The pedagogic experts hired to develop training came up with a training system, based on the training-technological model where the training was made a function of its own. The State Training Center was established and the training office of the Organization and Methods Division became the leader and coordinator of personnel training.

Alignment of the ALICE Inner Tracking System with cosmic-ray tracks

ALICE (A Large Ion Collider Experiment) is the LHC (Large Hadron Collider) experiment devoted to investigating the strongly interacting matter created in nucleus-nucleus collisions at the LHC energies. The ALICE ITS, Inner Tracking System, consists of six cylindrical layers of silicon detectors with three different technologies; in the outward direction: two layers of pixel detectors, two layers each of drift, and strip detectors. The number of parameters to be determined in the spatial alignment of the 2198 sensor modules of the ITS is about 13,000. The target alignment precision is well below 10 micron in some cases (pixels). The sources of alignment information include survey measurements, and the reconstructed tracks from cosmic rays and from proton-proton collisions. The main track-based alignment method uses the Millepede global approach. An iterative local method was developed and used as well. We present the results obtained for the ITS alignment using about 10^5 charged tracks from cosmic rays that have been collected during summer 2008, with the ALICE solenoidal magnet switched off.

Central Diffraction at ALICE

The ALICE experiment is shown to be well suited for studies of exclusive final states from central diffractive reactions. The gluon-rich environment ofthe central system allows detailed QCD studies and searches for exotic mesonstates, such as glueballs, hybrids and new charmonium-like states. It wouldalso provide a good testing ground for detailed studies of heavy quarkonia. Dueto its central barrel performance, ALICE can accurately measure the low-masscentral systems with good purity. The efficiency of the Forward MultiplicityDetector (FMD) and the Forward Shower Counter (FSC) system for detectingrapidity gaps is shown to be adequate for the proposed studies. With thisdetector arrangement, valuable new data can be obtained by tagging centraldiffractive processes.