Procedure for the fine delay adjustment of the CMS tracker

One of the crucial aspects of the commissioning of the CMS silicon tracker will be the absolute timing adjustment of each module, to accommodate both delays introduced by the hardware configuration and effects due to the time of flight of particles. The objective is to be optimally synchronized with the bunch-crossing to maximize the efficiency while minimizing the number of remnant hits from the adjacent bunch-crossings. In the present note, a procedure to reach that goal is studied. Monte Carlo studies as well as the analysis of data from the commissioning of the detector are used to assess the time needed and the resolution that can be achieved. Critical aspects are discussed, and results from the first implementation are presented

Outcome measures in a combined exercise rehabilitation programme for adults with COPD and chronic heart failure : A preliminary stakeholder consensus event

Combined exercise rehabilitation for chronic obstructive pulmonary disease (COPD) and chronic heart failure (CHF) is potentially attractive. Uncertainty remains as to the baseline profiling assessments and outcome measures that should be collected within a programme. Current evidence surrounding outcome measures in cardiac and pulmonary rehabilitation were presented by experts at a stakeholder consensus event and all stakeholders (n = 18) were asked to (1) rank in order of importance a list of categories, (2) prioritise outcome measures and (3) prioritise baseline patient evaluation measures that should be assessed in a combined COPD and CHF rehabilitation programme. The tasks were completed anonymously and related to clinical rehabilitation programmes and associated research. Health-related quality of life, exercise capacity and symptom evaluation were voted as the most important categories to assess for clinical purposes (median rank: 1, 2 and 3 accordingly) and research purposes (median rank; 1, 3 and 4.5 accordingly) within combined exercise rehabilitation. All stakeholders agreed that profiling symptoms at baseline were 'moderately', 'very' or 'extremely' important to assess for clinical and research purposes in combined rehabilitation. Profiling of frailty was ranked of the same importance for clinical purposes in combined rehabilitation. Stakeholders identified a suite of multidisciplinary measures that may be important to assess in a combined COPD and CHF exercise rehabilitation programme

Commissioning of the CMS tracker and preparing for early physics at the LHC

The Compact Muon Solenoid (CMS) experiment is a general purpose detector at the Large Hadron Collider. It has been designed and optimised to discover the Higgs boson and physics beyond the Standard Model. An early discovery of the Higgs boson is the collaboration's top priority and will require a good understanding of both the detector and the physics of the background processes, with a small integrated luminosity. This principle has been the driving force behind the work presented in this thesis. The Silicon Strip Tracker (SST) sits at the heart of the CMS detector. The development of core algorithms to commission the SST are reviewed and the process of live commissioning at the Tracker Integration Facility is described. A crowning success of this study is the calibration of 1.6M channels and their synchronisation to a cosmic muon trigger to within 1 ns. The SST is expected to produce five times more zero-suppressed data than any other CMS subdetector. As such its efficient handling within with High Level Trigger algorithms is paramount. The performance of the online hit reconstruction software is profiled, the inefficiencies are characterised and a new schema to focus on physics regions-of-interest only is proposed. As an example of its success, when running the single 't trigger path over n' -+ r VT events, hit reconstruction times were reduced from 838 ± 5 ms to only 5.13 ± 0.05 ms without any loss in tracking efficiency. The new software is now the tracker community's permanent online solution and is expected to become the offline solution in the near future. bbZO production at the LHC is of great interest, primarily due to its status as a background to a supersymmetric Higgs boson production process. The preparation for a cross section measurement with 100 pb-I of data (expected by the end of 2009) is made. The prominent backgrounds are identified and a signal selection strategy is developed and optimised using Monte Carlo. This study demonstrates that a cross section measurement with this amount of data is feasible. Finally, a method to estimate background from data is tested.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

New boundary conditions for the West Antarctic ice sheet: subglacial topography beneath Thwaites and Smith glaciers catchments

Airborne radar sounding over the Thwaites Glacier (TG) catchment and its surroundings provides the first comprehensive view of subglacial topography in this dynamic part of the West Antarctic Ice Sheet (WAIS) and reveals that TG is underlain by a single, broad basin fed by a dendritic pattern of valleys, while Smith Glacier lies within an extremely deep, narrow trench. Subglacial topography in the TG catchment slopes inland from a broad, low-relief coastal sill to the thickest ice of the WAIS and makes deep connections to both Pine Island Glacier and the Ross Sea Embayment enabling dynamic interactions across the WAIS during deglaciation. Simple isostatic rebound modeling shows that most of this landscape would be submarine after deglaciation, aside from an island chain near the present-day Ross-Amundsen ice divide. The lack of topographic confinement along TG's eastern margin implies that it may continue to widen in response to grounding line retreat

HD 213885b: a transiting 1-d-period super-Earth with an Earth-like composition around a bright (V = 7.9) star unveiled by TESS

This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©: 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.We report the discovery of the 1.008-d, ultrashort period (USP) super-Earth HD 213885b (TOI-141b) orbiting the bright (V = 7.9) star HD 213885 (TOI-141, TIC 403224672), detected using photometry from the recently launched TESS mission. Using FEROS, HARPS, and CORALIE radial velocities, we measure a precise mass of 8.8 ± 0.6 M⊕ for this 1.74 ± 0.05 R⊕ exoplanet, which provides enough information to constrain its bulk composition – similar to Earth’s but enriched in iron. The radius, mass, and stellar irradiation of HD 213885b are, given our data, very similar to 55 Cancri e, making this exoplanet a good target to perform comparative exoplanetology of short period, highly irradiated super-Earths. Our precise radial velocities reveal an additional 4.78-d signal which we interpret as arising from a second, non-transiting planet in the system, HD 213885c, whose minimum mass of 19.9 ± 1.4 M⊕ makes it consistent with being a Neptune-mass exoplanet. The HD 213885 system is very interesting from the perspective of future atmospheric characterization, being the second brightest star to host an USP transiting super-Earth (with the brightest star being, in fact, 55 Cancri). Prospects for characterization with present and future observatories are discussed

Spinning up a Daze: TESS Uncovers a Hot Jupiter orbiting the Rapid-Rotator TOI-778

NASA's Transiting Exoplanet Survey Satellite (TESS) mission, has been uncovering a growing number of exoplanets orbiting nearby, bright stars. Most exoplanets that have been discovered by TESS orbit narrow-line, slow-rotating stars, facilitating the confirmation and mass determination of these worlds. We present the discovery of a hot Jupiter orbiting a rapidly rotating (vsin(i)=35.1±1.0km/s) early F3V-dwarf, HD115447 (TOI-778). The transit signal taken from Sectors 10 and 37 of TESS's initial detection of the exoplanet is combined with follow-up ground-based photometry and velocity measurements taken from Minerva-Australis, TRES, CORALIE and CHIRON to confirm and characterise TOI-778b. A joint analysis of the light curves and the radial velocity measurements yield a mass, radius, and orbital period for TOI-778b of 2.76+0.24−0.23Mjup, 1.370±0.043Rjup and ∼4.63 days, respectively. The planet orbits a bright (V=9.1mag) F3-dwarf with M=1.40±0.05Msun, R=1.70±0.05Rsun, and logg=4.05±0.17. We observed a spectroscopic transit of TOI-778b, which allowed us to derive a sky-projected spin-orbit angle of 18∘±11∘, consistent with an aligned planetary system. This discovery demonstrates the capability of smaller aperture telescopes such as Minerva-Australis to detect the radial velocity signals produced by planets orbiting broad-line, rapidly rotating stars

Track Reconstruction with Cosmic Ray Data at the Tracker Integration Facility

The subsystems of the CMS silicon strip tracker were integrated and commissioned at the Tracker Integration Facility (TIF) in the period from November 2006 to July 2007. As part of the commissioning, large samples of cosmic ray data were recorded under various running conditions in the absence of a magnetic field. Cosmic rays detected by scintillation counters were used to trigger the readout of up to 15\,\% of the final silicon strip detector, and over 4.7~million events were recorded. This document describes the cosmic track reconstruction and presents results on the performance of track and hit reconstruction as from dedicated analyses