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DOE OSTI2017

Status and Update of the RaDIATE Collaboration R&D Program

The Radiation Damage In Accelerator Target Environments (RaDIATE) collaboration was founded in 2012 and currently consists of over 50 participants and 11 institutions globally. Due to the increasing power of future proton accelerator sources on target facilities, there is a critical need to further the understanding of the physical and thermo-mechanical radiation response of target facility materials. Thus, the primary objective of the RaDIATE collaboration is to draw on existing expertise in the nuclear materials and accelerator targets fields to generate new and useful materials data for application within the accelerator and fission/fusion communities. Current research activities of the collaboration include post irradiation examination (PIE) of decommissioned components from existing beamlines such as the NuMI beryllium beam window and graphite NT-02 target material. PIE of these components includes advanced microstructural analyses (SEM/TEM, EBSD, EDS) and micro-mechanic s technique such as nano-indentation, to help characterize any microstructural radiation damage incurred during operation. New irradiation campaigns of various candidate materials at both low and high energy beam facilities are also being pursued. Beryllium helium implantation studies at the University of Surrey as well as high energy proton irradiation of various materials at Brookhaven National Laboratory’s BLIP facility have been initiated. The program also extends to beam-induced thermal shock experiments using high intensity beam pulses at CERN’s HiRadMat facility, followed by advanced PIE activities to evaluate thermal shock resistance of the materials. The continuing research activities with preliminary results, as well as the future plans of the RaDIATE Collaboration R&D program will be discussed.

43 PARTICLE ACCELERATORS↗

DOE OSTI2018

DUNE in 10 Minutes [Slides]

The DUNE Science Collaboration is currently made up of over 1000 collaborators from 175 institutions (60% non-US) in 32 countries (35% of developing countries) plus CERN. The aim of this research program is to discover some of the greatest mysteries of the universe; origin of matter, unification of forces, black holes formation, among others. This project has a cooperative structure of consortia, working groups, task forces, boards and committees who have been working academically and administratively on the different key areas such as physics research, development of the detectors and prototypes, coordination of interfaces, and data analysis. One of the main objectives of this experiment is to motivate young people into science; leaders and members of the experiment, are very encouraging with younger members. On the other hand, this experiment goes beyond the experimental and practical outcomes in developing countries such as Colombia. This experiment is providing us with opportunities for doing science in our country, promoting progress, engaging new generations of Colombians and placing science on the political agenda.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2018

Final Technical Report: New Physics in Higgs or Higgsinos Using Vector Boson Fusion, Missing Energy, and ATLAS Trigger System Upgrades

The grant DE-SC0018007 supported Tae Min Hong and his research group at the University of Pittsburgh over a period of nine months leading up to his inclusion in Pittsburgh’s group grant DE-SC0007914. The work was done at the ATLAS Experiment at the Large Hadron Collider at CERN. Hong and his group supported the operations of the trigger subsystem, the upcoming upgrade of the level-1 calorimeter trigger subsystem, and the analysis of data collected by the detector. The analysis focused on the invisible decays of the Higgs boson and the compressed scenario in supersymmetry, both in the vector boson fusion mode of the colliding protons. This is part of a broad program of whether the Higgs boson is in agreement with the Standard Model expectations and whether new spacetime symmetries such as supersymmetry exists.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2018

Research on the ATLAS Experiment at the University of Illinois: Final Report

The goal of particle physics is to understand the Universe at its most fundamental level, including the constituents of matter and their interactions, and the nature of space and time itself. The quest to understand the fundamental building blocks of nature, and their interactions, is one of the most ambitious and enduring of human endeavors. Recent developments in particle physics and cosmology raise the exciting prospect that we are on the threshold of a major step forward in this pursuit. Facilities such as CERN's Large Hadron Collider (LHC) provide a unique window into the subatomic world to pursue this understanding. Mark Neubauer and his research group at the University of Illinois were supported over a nine-month period (07/01/2017 through 03/31/2018) to perform high-energy particle physics research on the ATLAS experiment at the LHC. The primary focus of this research was to search for physics beyond the standard model through an analysis of high-energy proton-proton collision data from the ATLAS experiment, with an emphasis on the Higgs boson as a sensitive tool for this search, and development of fast particle tracking systems for use the ATLAS trigger system.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2018

Nb-on-Cu Cavities for 700-1500 MHZ SRF Accelerators

Single crystal films of Nb were grown on MGO; RRR≈570 was measured in ≈4 µm films of Nb; cross-section SEM images showed that macro-particles embedded in the film had the same (100) crystal structure as the bulk film and were well adhered, hence did not pose a problem for vortex penetration. We coated 1.3 GHz cavities inside our vacuum chamber. We showed that we could grow uniform films on such cavities, but the best Qo measured was ~2E8, not acceptable. Next we coated 1.3 GHz cavities when pumping directly on the cavity. Arguing that heaters inside the vacuum chamber might be contaminating the coating, we pumped directly on the cavity so that it could be heated from outside (in air). The best Qo measured was ≈1E9, a record for all our cavity deposition. However, this encouraging result was tempered by Q-slope, which we attributed to impurities in the film due to the dirty (non-clean room) environment at AASC. It was decided to install the CED apparatus at JLab, to assemble, clean and coat under cleaner conditions. We next coated 1.3 GHz cavity at JLab. After shipping and installing the CED apparatus at JLab, two coating runs were completed before the project ended. Due to arcs inside the vacuum (faulty current leads) the runs ended prematurely, with ≈0.7 µm films. Since we had learned from coupon work that film thickness >2 µm (preferably 4 µm) were essential for good RF performance, the negative results were understandable. Indeed, the quadrupole resonator coatings for Sarah Aull at CERN had also indicated that a 2 µm coating would show adequate RF quality for LHC upgrades and for the ILC. JLab now has acquired the apparatus and knowledge of its operation. It is hoped that JLab will continue this potentially rewarding development and soon show the results that have eluded us.

43 PARTICLE ACCELERATORS↗

DOE OSTI2016

BNL Irradiation Damage Studies of the Metal Matrix Composite Mo-GR Considered for High Luminosity LHC Collimator Upgrade

A comprehensive experimental/analytical effort on the resilience of Mo-GR metal matrix composite to high energy proton beam irradiation combined with elevated temperatures has been undertaken at BNL on behalf of the CERN LHC Collimation effort as part of an effort to identify novel materials that will exhibit optimal performance in the high luminosity LHC upgrade. While the Mo-Gr composite was one of the four (4) different materials or composites (Mo, Glidcop, Cu-CD and Mo-Gr) that constituted the High Luminosity LHC collimation material campaign, this report focuses solely on Mo-GR with some reference to its constituents Mo and graphite (graphite studied in previous research or irradiation campaigns along with the carbonfiber composites). The multi-faceted study on Mo-GR (one of several different alloys and matrices) performed at BNL included the following stages: Irradiation damage phase using the 200 MeV proton beams of the BNL Linac and the BLIP target beamline. Specifically, Mo-GR samples encapsulated under vacuum in special capsules were exposed to direct protons as part of a multi-capsule, multi-material irradiation array. The long-term irradiation of ~8 weeks resulted in an accumulated fluence at the Mo-GR of ~10 21 p/cm 2 . The irradiation was conducted in two sessions (RUN 2013 and RUN 2014 of the BLIP operations in tandem with isotope production). Irradiation damage experiments using spallation neutrons at the BLIP beamline generated by 118 MeV protons that interact with and are stopped by an array of isotope producing targets. The Mo-GR capsule combined the effects of short-term proton irradiation and the effects of the mixed irradiating spectrum. Spallation-induced irradiation of Mo-GR at sub-zero temperatures utilizing the mixed field generated by spallation of 28 MeV protons of the BN Tandem on Mo targets Gamma spectrum analysis of the heavily irradiated Mo-Gr to enable the correlation of predicted isotope profile from Mo-Gr by transport codes and therefore the utilization of the validated transport code in other aspects of the damage induced on Mo-Gr by irradiation.

43 PARTICLE ACCELERATORS↗

DOE OSTI2015

A hybrid HTS/LTS Superconductor Design for High-Field Accelerator Magnets

High magnetic fields approaching 25 T are needed for significant advances in the physics reach of colliders for high energy physics. Large Hadron Collider (LHC) at CERN needs very high field magnets for planned energy and luminosity upgrades. The envisioned Muon Collider needs such magnets in several areas of the machine. High Temperature Superconductors (HTS) currently offer the best chance of producing hybrid magnets for these applications because HTS has a significantly higher critical current density than any other superconductor at high fields.)

43 PARTICLE ACCELERATORS↗

DOE OSTI2018

Scientific Summary Report for Early Career Award "High Precision Event Simulation for the LHC"

Particle physics has entered a new era with the discovery of the Higgs boson at the CERN Large Hadron Collider (LHC). To determine all properties of the boson and to reveal possible signatures of physics beyond the Standard Model it is crucial to make reliable predictions for both signal and background reactions. Monte-Carlo event generators produce such predictions fully differentially at the level of observed particles. They rely on various approximations to cope with the many-body dynamics of the problem and on models to deal with the non-abelian, nonlinear nature of Quantum Chromodynamics (QCD), the quantum-field theoretical model of the strong nuclear force. Dependence on the model parameters is one of the main uncertainties affecting measurements and searches at the LHC. Whenever possible such dependence must be reduced or eliminated.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2018

Quest for a Top Quark Partner and Upgrade of the Pixel Detector Readout Chain at the CMS

After the observation of a new particle at CERN experiments, which is consistent with being the Higgs boson, the partner of the top quark is the most anticipated candidate to be discovered next. In many extensions of the standard model of particle physics the principle of naturalness dictates that the top quark partner should exist and be relatively light, at or below the TeV scale. It is hence expected to be accessible at energies and luminosities provided by the LHC machine within the next years of running. This proposal calls for supporting the effort targeting the searches for the top quark partner at the CMS experiment. We focus on scenarios and techniques that have not yet been fully explored at CMS, and that carry a large potential for new physics discovery in the immediate future. The second part of the proposal focuses on the R&D effort aiming for continuing high-quality physics program at the CMS at the high instantaneous luminosities. We propose to take one of the leading roles in the forthcoming upgrade of the Pixel detector at the CMS, and upgrade the data acquisition readout chain that would increase the data volume throughput for the new detector.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2017

Search for heavy Majorana neutrinos in pp collisions at √s = 8 TeV with the CMS detector & photodetector and calorimeter R&D for particle colliders

This thesis contains both physics analysis and hardware studies. It consists of two primary sections: the results of a search for heavy Majorana mass neutrinos, using the event signature of same (like) sign charged electron pairs ($e^{\pm} e^{\pm}$ ) and two jets, and the results of studies to upgrade the Hadronic Forward (HF) and Hadronic Endcap (HE) subdetectors in the Compact Muon Solenoid (CMS) detector in response to the high intensity proton-proton collisions generated at the Large Hadron Collider (LHC) at European Organization for Nuclear Research (CERN, Conseil Europ\'{e}en pour la Recherche Nucl\'{e}aire). In this search for Majorana mass neutrinos, same sign dielectron ($e^{\pm} e^{\pm}$) + dijet events in the final state have been considered as a signature for neutrino particles. The analyzed data corresponds to an integrated luminosity of 19.7 fb\textsuperscript{-1} of proton-proton collisions at a center of mass energy of $\sqrt{s} = 8 \text{TeV}$, collected using the CMS detector during the 2012 operation at the LHC. Monte Carlo simulations accounting for the theoretical expectations of the Standard Model (SM) and the detector limitations are used to prototype the experiment and to test proposed analysis steps. No excess of events is observed in the data beyond the expected SM background. Upper limits are set on the mixing element squared, $|{V}_{eN}|^{2}$, of the heavy Majorana neutrino with standard model neutrinos, as a function of Majorana neutrino mass for masses in the range of 40-500 $GeV/c^2$. The detector upgrade search comprises three sections of this thesis. The first section describes the test results of 1785 multianode Hamamatsu R7600U-200-M4 photomultiplier tubes (PMT) in numerous parameters such as gain, dark current, and timing characteristics, which provide insights on the expected performance of the upgraded CMS-HF detector. These PMTs replaced the previous single anode R7525 PMTs because the glass windows of previous PMTs are the source of Cherenkov radiation, which causes a background noise in the experiment. The second section reports characterization results of two types of PMTs in a novel operation mode for Secondary Emission (SE) Ionization Calorimetry, which is a novel technique to measure electromagnetic shower particles in extreme radiation environments. The third section presents the test results of novel scintillating materials for CMS experiment in specific and future particle accelerators in general. These materials are Polyethylene Naphthalate (PEN), Polyethylene Terephthalate (PET), high efficiency mirror (HEM) and quartz plates with various organic and inorganic coating materials such as p-Terphenyl (pTp), Anthracene and Gallium-doped Zinc Oxide (ZnO:Ga). We have investigated them for radiation hardness, light yield, timing characteristics, and scintillation and transmission properties.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2015

Characterization of the initial state and medium properties of heavy-ion collisions at ALICE

This report summarizes the key achievements from my "Characterization of the initial state and medium properties of heavy-ion collisions at ALICE" award. This report summarizes the key achievements from DOE award, which started February 1st 2015, and ended January 31st 2018. The award funded experimental research into relativistic heavy-ion collisions at two facilities: The ALICE detector at the Large Hadron Collider (LHC) at CERN, and the STAR detector at Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory. Relativistic heavy-ion collisions aim to create the Quark Gluon Plasma (QGP) is a unique state where the building blocks of nuclear matter, quarks and gluons, melt and move freely over the volume of the nucleus. It is believed that the universe temporarily existed in such a state shortly after the big bang, where the temperatures needed for this transition are roughly 100,000 times bigger than the temperature at the center of the Sun. Experimental data collected over the past decade at RHIC have provided evidence that the QGP has been created in the laboratory.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2018

A Letter of Intent for MATHUSLA: a dedicated displaced vertex detector above ATLAS or CMS.

In this Letter of Intent we propose the construction of MATHUSLA (MAssive Timing Hodoscope for Ultra-Stable neutraL pArticles), a dedicated large-volume displaced vertex detector (DV) for the HL-LHC on the surface above ATLAS or CMS. Such a detector, which can be built using existing technologies with a reasonable budget in time for the HL-LHC upgrade, could search for neutral long-lived particles (LLPs) without trigger limitations and with very low or zero backgrounds, allowing it to probe LLP cross sections and lifetimes up to several orders of magnitude beyond the reach of ATLAS or CMS. MATHUSLA would also act as a cutting-edge cosmic ray telescope at CERN, exploring many open questions in cosmic ray and astro-particle physics.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

DOE OSTI2017

D-DMTD: Digital Dual Mixer Time Difference

The digital design discussed in the following document is inspired by the digital dual mixer time difference circuit and based on the white paper, Digital femtosecond time difference circuit for CERN's timing system. DMTD is originally an analog technique that measures the time difference between two events with high precision using a commercial time interval counter. Our project applies this analog concept to a digital system programmed onto a Microsemi ProASIC3E FPGA (Field- Programmable Gate Array). D-DMTD is a digital system theoretically capable of measuring the time difference between two digital clock signals with very fine resolution (sub-picosecond) using a relatively low frequency counter. The system essentially acts as a digital phase detector with femtosecond time resolution. The main concern with this processing technique is its feasibility and accuracy when implemented on an FPGA. Another concern is the environmentally-induced, horizontal phase noise in the digital signals; this 'litter" jeopardizes the fidelity of the clocks and generates glitches in the signals. Thus, the majority of the work was focused on determining under what conditions the digital design performs optimally and generates the most accurate estimations for the phase shift.

42 ENGINEERING↗

DOE OSTI2019

Search for the Higgs and Physics Beyond the Standard Model with the CMS Electromagnetic Calorimeter

The Compact Muon Solenoid (CMS) Experiment is a general purpose particle detector experiment at the Large Hadron Collider (LHC) at the European Laboratory for Nuclear Research (CERN). The LHC is the world’s highest energy particle collider, providing proton-proton collisions up to a center-of-mass energy of 13 TeV. The primary aim of the LHC and the CMS Experiment is to discover new physics at this high energy frontier. In 2012, the discovery of the Higgs boson at the LHC marked a crucial milestone in the Standard Model (SM) of particle physics and ushered in the beginning of a new era of exploration at the high energy frontier. Since this discovery, two key areas of study were the characterization of the new particle to confirm that it is, indeed, the predicted SM Higgs boson and also the examination of possible deviations from the SM that may hint at new physics. As a member of the CMS collaboration, the main interest of PI Orimoto has been the study of electromagnetic objects (electrons and photons) as a critical ingredient in the characterization of the Higgs boson, and as a window into physics beyond-the-SM (BSM). To this end, the Orimoto group has led numerous physics analyses ranging from SM Higgs boson studies, searches for exotic production and decay of the Higgs boson, as well as searches for supersymmetric particles. Moreover, the Orimoto group has made significant contributions to the CMS electromagnetic calorimeter (ECAL), the sub-detector responsible for the precise measurement of the energies of electrons and photons. The Orimoto group’s contributions have been recognized with many leadership roles and high profile conference presentations. This report outlines the group’s products and accomplishments from the award period (June 2013 through July 2018).

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2018

Development and Validation of a Geant4 Radiation Shielding Simulation Framework

Geant4 (`Geometry and Tracking') is a C++ Monte- Carlo simulation toolkit developed by the Geant4 Collaboration under CERN and is used to describe inter- actions between particles and matter. It has been shown, through significant benchmarking against physical experiments and other software, to be remarkably accurate at simulating interactions between particles and matter. Currently, Geant4 is being used on world-wide projects such as ATLAS, CMS, Muon g-2, and ILC, largely due to being accurate, open-source, and written in a modern language. This openness and modernity is striking when compared to other Monte-Carlo simulation toolkits such as the Fortran toolkit MCNP (Monte-Carlo N-Particle code), which is restricted in acquisition and use by the US government. Despite barriers in the use of MCNP and having been written in an antiquated language, MCNP is still considered industry-standard for many fields, including radiation shielding. This paper details the development and validation of a radiation shielding simulation framework in Geant4 aimed at flexibility and ease of simulations with the goal of replacing MCNP scripts.

43 PARTICLE ACCELERATORS↗

DOE OSTI2019

Development of 3D diamond detectors for detector applications at ultra high luminosity facilities

During this project our group has succeeded in producing and measuring a number of 3D diamond devices. We have worked with manufacturers and shown that poly-crystalline CVD (pCVD) diamond can be grown reliably with a 5% uniformity in industry. We have produced 3D diamond devices and scaled up the production technology from roughly 100 cells on a device to 4000 cells on a device. We have increased the column yield from 92% to 99%. We have reduced the cell size from our safe initial choice 150μm x 150μm cells to the HL-LHC size of 50μm x 50μm cells. We have reduced the column diameter from 6-10 μm to 2.6 μm. In beam tests we have quantified the amount of charge each 3D device yields for minimizing ionizing particles and compared this to that produced by a planar diamond device. Very recently, we produced the first 3D diamond pixel devices read out with both ATLAS and CMS pixel electronics, tested them in particle beams at CERN and PSI. Finally we have successfully tested the first irradiated 3Ddiamond device after a fluence of 3.5 x 10 15 800 MeV p/cm 2 .

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

DOE OSTI2017

Highlights from BNL and RHIC 2016

The Relativistic Heavy Ion Collider (RHIC) was designed and built at Brookhaven National Laboratory (BNL) and is one of the two remaining operating hadron colliders in the world, the other being the CERN LHC. There were also several previous facilities at BNL including the 30 GeV Alternating Gradient Synchrotron (AGS–now the RHIC injector) where the muon-neutrino, and CP violation were discovered and the 3 GeV Cosmotron where the $K^0_2$ was discovered. There have been many other discoveries at BNL.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

DOE OSTI2019

Preservation of the distribution of beam particles with respect to longitudinal oscillation amplitude in a 3 to 1 bunch merge

In the work presented here we show in detail how the 3 to 1 bunch merge can be set up so that it preserves the distribution of beam particles with respect to longitudinal oscillation amplitude. This is an elaboration based on the work presented in reference 1. The desired merge is achieved by slowly reducing the area inside the three-lobed separatrix that contains the beam while keeping the areas of the three lobes equal to one another. A sequence of RF voltages that does the job is found by employing a numerical integration routine and a search algorithm. The integration routine calculates the areas of the three lobes for given voltages. This is used by the search algorithm to nd voltages that give three lobes of equal area. The resulting voltages are listed in Section 12 in order of decreasing lobe area. These may be multiplied by a common scaling factor to make the scheme work for any given longitudinal emittance in any given machine. The analytic basis of the scheme is presented in Sections 2 through 13. (These sections may be treated as appendices.) Demonstration of the merge is done by simulation. The results are shown in Figures 1 through 39 and are discussed in Section 1. References [1] through [10] and those cited therein provide a history of bunch merging (and splitting) relevant to the present work. Refs. [1] and [2] record the early work done at CERN. Refs. [3] through [10] record the setup and study of the 2 to 1 and 3 to 1 merges used in Booster and AGS. In particular, Refs. [9] and [10] record the recent work of K. Zeno who proposed and developed the 3 to 1 bunch merge in Booster. It is this merge that is studied in the present work.

43 PARTICLE ACCELERATORS↗