Collaborative Research: Construction of the Upstream Tracker for the LHCb Upgrade

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OverviewOne of the major intellectual achievements of the 20th century was the development of the Standard Model (SM) of particle physics. This model succeeded in classifying all of the elementary particles known at the time into a hierarchy of groups having similar quantum properties. The validity of this model to date was recently confirmed by the discovery of the Higgs boson at the Large Hadron Collider (LHC)at CERN. However, the Standard Model as it currently exists, leaves open many questions about the universe. These include why matter dominates over anti-matter in the Universe (CP violation), the values of the masses of the fundamental constituents, the quarks and the leptons, the size of the mixings among the quarks, and separately among the leptons, and the properties of dark matter. Most explanations require the presence of new forces, which we call Beyond the Standard Model Physics (BSM).The LHC is the premier Energy Frontier particle accelerator in the world and is currently operating at the CERN laboratory near Geneva Switzerland. It is one of the foremost facilities for answering these BSM questions.Large Hadron Collider beauty (LHCb) is the first experiment designed specifically to study the decays of hadrons containing beauty or charm quarks at a hadron collider. The goal of LHCb is to identify new physics in nature by examining the properties of hadrons containing these quarks. New physics, or new forces, are manifest by particles, as yet to be discovered. These particles would modify decay rates and CP violating asymmetries, and thus allow new phenomena to be observed indirectly. In direct searches for new particles, the accelerators' energy must be high enough to allow the particle to be produced. In indirect searches effects of new particles can be seen even if they have a much higher mass than can be seen directly, because the effects are quantum in nature, and appear in calculations where the particles are "virtual" so they are emitted and absorbed over short times. LHCb has operated very successfully starting in late 2010. The data are being analyzed and published. The experiment has shown many results, but none so far have clearly demonstrated new physics. LHCb has proposed an upgrade to be completed in the 2018-2019 time-frame when the LHC accelerator will not be running. This upgrade will allow LHCb to collect an order of magnitude more data in decay modes that will either show new physics or severely restrict the allowed mass range. LHCb is comprised of about 10 different sub-detectors or sub-systems. The Syracuse, Maryland, Cincinnati and MIT groups participating in this award have the responsibility of upgrading a part of the charged particle tracking system. The intent is to significantly enhance the capabilities of this system above and beyond the requirement that data can be taken at an order of magnitude higher luminosity.Intellectual MeritThe intellectual merit of this award is that it is part of an upgrade of LHCb that will allow a much more sensitive search for BSM physics. The main deliverable will be a new inner tracking device, the Upstream Tracker (UT). This device will increase the data throughput over the current tracking device by an order of magnitude, allowing the LHCb experiment to probe BSM physics. The UT, which replaces the current tracker, will consists of four planes of single-sided 250 micron thick silicon strip detectors, read out by a custom-made front-end electronic integrated circuit. With its reduced material budget and optimized segmentation as a function of the distance from the beam line, it plays a crucial role in reducing the rate of fake tracks and in providing fast momentum measurements in the residual field of the dipole magnet. Broader ImpactsThe broader impacts of this work span several areas. Undergraduate and graduate students will be direct participants in the construction and testing of the detector that will be constructed. For many years a steady stream of undergraduate and graduate students have been working in the PIs' laboratories, where it is a tradition to ensure that graduate students have both hardware experience as well as data analysis capabilities. The upgrade work will be integrated into the Syracuse Quarknet program to involve high school teachers and some of their better students as well. Test results from this detector will be discussed at conferences and published. This detector is an integral part of the LHCb Upgrade and is essential for LHCb to continue to produce cutting edge physics results.