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Cohen, E.

Publications and source records attributed to Cohen, E..

At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Design of the ECCE detector for the Electron Ion Collider

The EIC Comprehensive Chromodynamics Experiment (ECCE) detector has been designed to address the full scope of the proposed Electron Ion Collider (EIC) physics program as presented by the National Academy of Science and provide a deeper understanding of the quark-gluon structure of matter. To accomplish this, the ECCE detector offers nearly acceptance and energy coverage along with excellent tracking and particle identification. The ECCE detector was designed to be built within the budget envelope set out by the EIC project while simultaneously managing cost and schedule risks. Finally, this detector concept has been selected to be the basis for the EIC project detector.

47 OTHER INSTRUMENTATION↗
DOE OSTI2023

Evaluation of longitudinal double-spin asymmetry measurements in semi-inclusive deep-inelastic scattering from the proton for the ECCE detector design

The evaluation of the measurement of double-spin asymmetries for charge-separated pions and kaons produced in deep-inelastic scattering from the proton using the ECCE detector design concept is presented, for the combinations of lepton and hadron beam energies of 5 × 41 GeV 2 and 18 × 275 GeV 2 . The study uses unpolarised simulated data that are processed through a full GEANT simulation of the detector. These data are then reweighted at the parton level with DSSV helicity distributions and DSS fragmentation functions, in order to generate the relevant asymmetries, and subsequently analysed. Furthermore, the performed analysis shows that the ECCE detector concept provides the resolution and acceptance, with a broad coverage in kinematic phase space, needed for a robust extraction of asymmetries. This, in turn, allows for a precise extraction of sea-quark helicity distributions.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2023

Design and simulated performance of calorimetry systems for the ECCE detector at the electron ion collider

Here, we describe the design and performance the calorimeter systems used in the ECCE detector to achieve the overall performance specifications cost-effectively with careful consideration of appropriate technical and schedule risks. The calorimeter systems consist of three electromagnetic calorimeters, covering the combined pseudorapidity range from -3.7 to 3.8 and two hadronic calorimeters covering a combined range of -1.1<η<3.8. Key calorimeter performances which include energy and position resolutions, reconstruction efficiency, and particle identification will be presented.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2023

ECCE unpolarized TMD measurements

For this work, we performed feasibility studies for various measurements that are related to unpolarized TMD distribution and fragmentation functions for the ECCE detector proposal. The processes studied include semi-inclusive Deep inelastic scattering (SIDIS) where single hadrons (pions and kaons) were detected in addition to the scattered DIS lepton. The single hadron cross sections and multiplicities were extracted as a function of the DIS variables x and Q 2 , as well as the semi-inclusive variables z, which corresponds to the momentum fraction the detected hadron carries relative to the struck parton and P T , which corresponds to the transverse momentum of the detected hadron relative to the virtual photon. The expected statistical precision of such measurements is extrapolated to accumulated luminosities of 10 fb –1 and potential systematic uncertainties are approximated given the deviations between true and reconstructed yields. The expected uncertainties are then used to obtain the expected impact on the related TMD distribution and fragmentation functions. We find that the ECCE detector proposal fulfills the physics requirements on these channels as detailed in the EIC Yellow Report.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
NASA NTRS2001

Comparison of full-aperture interferometry to sub-aperture stitched interferometry for a large diameter fast mirror

The Herschel Space Observatory (formerly known as FIRST) consists of a 3.5 m space telescope. Stitching sub aperture interferograms may offer considerable cost savings during testing of the flight telescope as compared to other techniques. A comparative demonstration is presented of interferogram stitching techniques that enable a composite map of a 3-D surface to be assembled from a sequence of sub-aperture measurements. This paper describes the fundamental procedures for stitching together component data sets and demonstrates such techniques with real data sets.

carbon fiber composite cryogenic optics high slope↗
NASA NTRS2001

Cryogenic (70K) measurement of an all-composite 2-meter diameter mirror

The Herschel Space observatory (formerly known as FIRST) consists of a 3.5 m space telescope. In order to develop lightweight telescope technology suitable for this mission, COI designed and fabricated aspherical, f/1 2 m aperture prototype primary mirror using solely carbon fiber reinforced polypmer (CFR) materials. To assess the performance of this technology, optical metrology of the mirror surface was performed from ambient to an intended operational temperature for IR-telescopes of 70K. Testing was performed horizontally in a cryogenic vacuum chamber at Arnold Engineering Development Center (AEDC), Tennessee.

lightweight mirrors cryogenic testing composite ma↗
NASA NTRS2001

Optical metrology for testing an all-composite 2-meter diameter mirror

The Herschel Space Observatory (formerly known as FIRST) consists of a 3.5 m space telescope designed for use in the long IR and sub-milimeter wavebands. To demonstrate the viability of a carbon fiber composite telescope for this application, Composite Optics Incorporated (COI) manufactured a fast (f/1), large (2 m), lightweight (10.1 kg/m squared) demonstration mirror. A key challenge in demonstrating the performance of this novel mirror was to characterize the surface accuracy at cryogenic (70 K) temperatures. A wide variety of optical metrology techniques were investigated and a brief survey of empirical test results and limitations of the various techniques will be presented in this paper. Two complementary infrared (IR)techniques operating at a wavelength of 10.6 microns were chosen for further development: (1) IR Twyman-Green Phase Shifting Interferometry (IR PSI) and (2) IR Shack-Hartmann (IR SH) Wavefront Sensing. Innovative design modifications made to an existing IR PSI to achieve high-resolution, scannable, infrared measurements of the composite mirror are described. The modified interferometer was capable of measuring surface gradients larger than 350 microradians. The design and results of measurements made with a custom-built IR SH Wavefrong Sensor operating at 10.6 microns are also presented. A compact experimental setup permitting simultaneous operation of both the IR PSI and IR SH tools is shown. The advantages and the limitations of the two key IR metrology tools are discussed.

IR metrology phase shifting interferometry Shack-H↗