Brent Yates

An increasingly frequent challenge faced in HEP data analysis is to characterize the agreement between a prediction that depends on a dozen or more model parameters—such as predictions coming from an effective field theory (EFT) framework—and the observed data. Traditionally, such characterizations take the form of a negative log likelihood (NLL) function, which can only be evaluated numerically. The lack of a closed-form description of the NLL function makes it difficult to convey results of the statistical analysis. Typical results are limited to extracting “best fit” values of the model parameters and 1D intervals or 2D contours extracted from scanning the higher dimensional parameter space. It is desirable to explore these high-dimensional model parameter spaces in more sophisticated ways. One option for overcoming this challenge is to use a neural network to approximate the NLL function. This approach has the advantage of being continuous and differentiable by construction, which are essential properties for an NLL function and may also provide useful handles in exploring the NLL as a function of the model parameters. In this talk, we describe the advantages and limitations of this approach in the context of applying it to a CMS data analysis using the framework of EFT.

BACKGROUND: Distraction osteogenesis (DO) is a technique of bone lengthening that makes use of the body's natural healing capacity. An osteotomy is created and a rigid distraction device is attached to the bone. After a latency period, the device is activated 2-4 times per day for a total of 1 mm/day of bone lengthening. This technique is used to correct a variety of congenital and acquired deformities of the mandible, midface and long bones. To shorten the treatment period and to eliminate the complications of patient activation of the device, an automated continuous distraction device would be desirable. It has been reported that continuous distraction generates adequate bone with lengthening at a rate of 2 mm/day, thereby reducing the treatment time. METHOD OF APPROACH: The device we describe here uses miniature high-pressure hydraulics, position feedback, and a digital controller to achieve closed-loop control of the distraction process. The implanted actuator can produce up to 40N of distraction force on linear trajectories as well as curved distraction paths. In the paper we detail the spring-powered hydraulic reservoir, controller, and user interface. RESULTS: Experiments to test the new device design were performed in a porcine cadaver head and in live pigs. In the cadaver head, the device performed an 11-day/11 mm distraction with a root-mean-squared position error of 0.09 mm. The device functioned for periods of several days in each of five live animals, though some component failures occurred, leading to design revisions. CONCLUSIONS: The test series showed that the novel design of this system provides the capabilities necessary to automate distraction of the mandible. Further developments will focus on making the implanted position sensor more robust and then carrying out clinical trials.

The high instantaneous luminosities expected following the upgrade of the Large Hadron Collider (LHC) to the High-Luminosity LHC (HL-LHC) pose major experimental challenges for the CMS experiment.A central component to allow efficient operation under these conditions is the reconstruction of charged particle trajectories and their inclusion in the hardwarebased trigger system.There are many challenges involved in achieving this: a large input data rate of about 20-40 Tb/s; processing a new batch of input data every 25 ns, each consisting of about 15,000 precise position measurements and rough transverse momentum measurements of particles ("stubs"); performing the pattern recognition on these stubs to find the trajectories; and producing the list of trajectory parameters within 4 µs.This paper describes a proposed solution to this problem, specifically, it presents a novel approach to pattern recognition and charged particle trajectory reconstruction using an all-FPGA solution.The results of an end-to-end demonstrator system, based on Xilinx Virtex-7 FPGAs, that meets timing and performance requirements are presented along with a further improved, optimized version of the algorithm together with its corresponding expected performance.

To develop and test a novel, hydraulic, continuous, automated distraction device capable of 3D movements for treatment of mandibular deformities.We used 2 cadaveric and 5 live female Yucatan minipigs to test the distractor. The 3 components (miniature buried distractor, external power and control box, and user interface on handheld computer) operate on a closed loop in which the hydraulic pulse strength correlates with the resistance of the bone and soft tissue. The system auto-adjusts to correct any discrepancy between the actual and desired position of mandibular fragments. The distraction protocol included 0-day latency, 1 mm (divided into 94 increments) per day, and 24 days' fixation. Clinical examination was performed and lateral and anteroposterior cephalometric radiographs were obtained preoperatively and postoperatively, at mid distraction osteogenesis (DO), end DO, and end fixation. Position information was obtained through the user interface.Both cadaveric trials resulted in the desired distraction gap (11 to 12 mm), with all components functioning as designed. In 4 of the 5 live animals, distraction averaged 7.29 mm (range, 5 to 11 mm) over 12 days of activation. In 3 of the 5 live animals, the osteotomy gap filled in with bone by 24 days of fixation. Two animals were sacrificed prematurely (1 at mid DO and 1 at end DO) because vital components malfunctioned.The device is capable of automated, continuous, hydraulically powered DO at a rate of 1 mm/d. Future work will be directed at fortifying the device components and testing it in larger numbers of animals at varying distraction rates.

We present normalized doubly differential cross sections (DDCS's) for the near-threshold, electron-impact single ionization of argon and krypton, similar to those taken earlier for Ne and Xe [Yates et al., J. Phys. B 42, 095206 (2009)]. The Ar measurements were taken at incident energies of 17, 18, 20, and 30 eV while the Kr measurements were taken at 15, 16, 17.5, and 20 eV. The DDCS scattering angles range from 15${}^{\ifmmode^\circ\else\textdegree\fi{}}$ to 120${}^{\ifmmode^\circ\else\textdegree\fi{}}$. The differential data are initially normalized to available experimental cross sections for excitation of the ground ${\mathit{np}}^{6}$ to the ${\mathit{np}}^{5}(n+1)s$ excited states of the noble gas and, after integration, to well-established experimental total ionization cross sections of Rapp and Englander-Golden [J. Chem. Phys. 43, 1464 (1965)].

Normalized doubly differential cross sections (DDCSs) for the electron impact single ionization of Ne and Xe are presented. The Ne measurements are taken at incident energies of 23.5 eV, 25 eV, 30 eV and 40 eV while the Xe measurements are taken at 14 eV, 15 eV and 20 eV. Scattering angles in the experiment range from 15? to 120?. The measurements use a moveable target method for an accurate determination of the experimental background. Normalization of the differential data is initially made to available experimental cross sections for excitation of the ground np6 to the np5 (n + 1)s excited states of the noble gas and then, if necessary after integration, to available experimental total ionization cross sections. We show that our single differential cross sections, derived from integrating the DDCSs, show a convex profile (frown) for Ne whereas they are concave (smile) for Xe similar to what is observed for He and we suggest a tentative mechanism for this effect.

Even Einstein has to be wrong sometimes. However, when Einstein was wrong he created a 70 year debate about the strange behavior of quantum mechanics. His debate helped prove topics such as the indeterminacy of particle states, quantum entanglement, and a rather clever use of quantum entanglement known as quantum teleportation.

Signs of new physics are probed in the context of an Effective Field Theory using events containing one or more top quarks in association with additional leptons. Data consisting of proton-proton collisions at a center-of-mass energy of $\sqrt{s}=$13 TeV was collected at the LHC by the CMS experiment in 2017. We apply a novel technique to parameterize 16 dimension-six EFT operators in terms of the respective Wilson coefficients (WCs). A simultaneous fit is performed to the data in order to extract the two standard deviation confidence intervals (CIs) of the 16 WCs. The Standard Model value of zero is completely contained in most CIs, and is not excluded by a statistically significant amount in any interval.

Even Einstein has to be wrong sometimes. However, when Einstein was wrong he created a 70 year debate about the strange behavior of quantum mechanics. His debate helped prove topics such as the indeterminacy of particle states, quantum entanglement, and a rather clever use of quantum entanglement known as quantum teleportation.

Frontiers Abstracts Design and Testing of a Durable Implantable Position Sensor Brian Murphy, Brian Murphy Search for other works by this author on: This Site PubMed Google Scholar John Magill, John Magill Physical Sciences Inc. Search for other works by this author on: This Site PubMed Google Scholar Roger Kromann, Roger Kromann Search for other works by this author on: This Site PubMed Google Scholar Brent Yates, Brent Yates Embedded Systems Design Search for other works by this author on: This Site PubMed Google Scholar Brad Tricomi, Brad Tricomi Search for other works by this author on: This Site PubMed Google Scholar Zach Peacock, Zach Peacock Search for other works by this author on: This Site PubMed Google Scholar Maria Papadaki, Maria Papadaki Search for other works by this author on: This Site PubMed Google Scholar Maria Troulis, Maria Troulis Search for other works by this author on: This Site PubMed Google Scholar Leonard Kaban Leonard Kaban Massachusetts General Hospital Search for other works by this author on: This Site PubMed Google Scholar Author and Article Information John Magill Physical Sciences Inc. Brent Yates Embedded Systems Design Leonard Kaban Massachusetts General Hospital J. Med. Devices. Mar 2012, 6(1): 017552 (1 pages) https://doi.org/10.1115/1.4026730 Published Online: March 12, 2012 Article history Received: May 27, 2011 Revision Received: November 7, 2011

Total cross sections for electron impact and resonant structure for ethanol and methanol are reported.

Doubly differential cross-sections for the single electron impact ionization of Ne and Xe have been measured at several energies below the second ionization energy. The results indicate that the ionization of Ne is strongly influenced by the polarization of the ionized 22P3/2,1/2 core, where as this influence is significantly reduced for Xe. Single differential cross-sections are derived from the doubly differential cross-sections and for Xenon these show profiles similar to Helium (smile), whereas for Neon they show a dissimilar profile (frown).

A first measurement of the $\mathrm{b}$ quark fragmentation function at the LHC is presented. Charmed meson candidates produced via semi-leptonic $\mathrm{t\overline{t}}$ decays ($\mathrm{t} \to \mathrm{b}\mathrm{W} \to$ b-jet $\ell ν$) are used as a proxy for the parent $\mathrm{B}$ meson. Templates are generated at various values of the fragmentation shape parameter $r_{\mathrm{b}}$, and are fit to the data to measure the value of $r_{\mathrm{b}}$. The final fit result is $r_{\mathrm{b}}=0.855 \pm 0.037\;\mathrm{(stat)} \pm 0.031\;\mathrm{(syst)}$. This is the first measurement of the $\mathrm{b}$ quark fragmentation function within a color rich environment, and is consistent with previous results from $e^+e^-$ colliders.

Author(s): Yates, Brent | Advisor(s): Wimpenny, Stephen; Clare, Robert | Abstract: In this analysis we present the first results of the measurement of the shape parameter rb in the Lund-Bowler fragmentation function for the b quark in a ttbar environment. The analysis uses charmed mesons produced in the leptonic decays of ttbar at sqrt(s)=13 TeV in the CMS detector using the full 2016 dataset with an integrated luminosity of 35.9 fb^-1. The charged particle decays of J/Psi -g mu^+ mu^- and D^0 -g K pi are used as proxies for the parent b quark via the ratio xB (the pT of the charmed meson divided by the sum of the transverse momentum of all charged particles in the jet containing the meson) to measure the shape parameter rb. The shape parameter rb is measured to be rb = 0.841 +/- 0.014 (stat) +/- 0.031 (syst).

The High-Luminosity LHC will put significant demands on trigger systems. To control trigger thresholds, the CMS Collaboration is designing a novel Level-1 track trigger. The Outer Tracker will use modules with pairs of sensor layers to read out hits compatible with charged particles above 2-3 GeV. The system will combine these front-end trigger primitives to reconstruct tracks, providing a measurement of P_T, \eta , \phi, and z_0. This presentation will introduce the CMS L1 track finding system: the algorithm and its estimated performance, hardware prototypes, and the unique challenges associated with this system.

The High-Luminosity LHC will put significant demands on trigger systems. To control trigger thresholds, the CMS Collaboration is designing a novel Level-1 track trigger. The Outer Tracker will use modules with pairs of sensor layers to read out hits compatible with charged particles above 2-3 GeV. The system will combine these front-end trigger primitives to reconstruct tracks, providing a measurement of $p_{\mathrm{T}}$, $\eta$ , $\phi$, and $z_{0}$. This presentation will introduce the CMS L1 track finding system: the algorithm and its estimated performance, hardware prototypes, and the unique challenges associated with this system.

Signs of new physics are probed in the context of an Effective Field Theory using events containing one or more top quarks in association with additional leptons. Data consisting of proton-proton collisions at a center-of-mass energy of $\sqrt{s}=$13 TeV was collected at the LHC by the CMS experiment in 2017. We apply a novel technique to parameterize 16 dimension-six EFT operators in terms of the respective Wilson coefficients (WCs). A simultaneous fit is performed to the data in order to extract the two standard deviation confidence intervals (CIs) of the 16 WCs. The Standard Model value of zero is completely contained in most CIs, and is not excluded by a statistically significant amount in any interval.