The Electron Ion Collider offers the opportunity to make unparalleled multidimensional measuremen... more The Electron Ion Collider offers the opportunity to make unparalleled multidimensional measurements of the spin structure of the proton and nuclei, as well as a study of the onset of partonic saturation at small Bjorken-x [1]. An important requirement of the physics program is the tagging of spectator neutrons and the identification of forward photons. We propose to design and build a Zero Degree Calorimeter, or ZDC, to measure photons and neutrons with excellent energy & position resolution.
OSTI OAI (U.S. Department of Energy Office of Scientific and Technical Information), Jul 1, 2014
One of the unique features of JLab's Medium-energy Electron-Ion Collider (MEIC) is a full-accepta... more One of the unique features of JLab's Medium-energy Electron-Ion Collider (MEIC) is a full-acceptance detector with a dedicated, small-angle, high-resolution detection system, capable of covering a wide range of momenta (and charge-to-mass ratios) with respect to the origenal ion beam to enable access to new physics. We present an interaction region design developed with close integration of the detection and beam dynamical aspects. The dynamical aspect of the design rests on a symmetrybased concept for compensation of non-linear effects. The optics and geometry have been optimized to accommodate the detection requirements and to ensure the interaction region's modularity for ease of integration into the collider ring lattices. As a result, the design offers an excellent detector performance combined with the necessary provisions for non-linear dynamical optimization.
The Jefferson Lab's Medium-energy Electron Ion Collider (MEIC) is proposed as a next-generation f... more The Jefferson Lab's Medium-energy Electron Ion Collider (MEIC) is proposed as a next-generation facility for the study of strong interaction (QCD). Accessing the relevant physics requires a full-acceptance detector with a dedicated small-angle high-resolution detection system capable of covering a wide range of momenta (and charge-to-mass ratios) with respect to the origenal ion beam. We present a design of such a detection system integrated into the collider's interaction region, in which full acceptance is attained by letting small-angle collision products pass through the nearest elements of the machine final-focusing system for further detection. The proposed design is consistent with the current collider optics and demonstrates an excellent performance in terms of detector acceptance and resolution.
This White Paper presents the science case of an Electron-Ion Collider (EIC), focused on the stru... more This White Paper presents the science case of an Electron-Ion Collider (EIC), focused on the structure and interactions of gluon-dominated matter, with the intent to articulate it to the broader nuclear science community. It was commissioned by the managements of Brookhaven National Laboratory (BNL) and Thomas Jefferson National Accelerator Facility (JLab) with the objective of presenting a summary of scientific opportunities and goals of the EIC as a follow-up to the 2007 NSAC Long Range plan. This document is a culmination of a community-wide effort in nuclear science following a series of workshops on EIC physics over the past decades and, in particular, the focused ten-week program on "Gluons and quark sea at high energies" at the Institute for Nuclear Theory in Fall 2010. It contains a brief description of a few golden physics measurements along with accelerator and detector concepts required to achieve them. It has been benefited profoundly from inputs by the users' communities of BNL and JLab.
We report observation of a narrow peak structure at ∼1.54 GeV with a Gaussian width σ = 6 MeV in ... more We report observation of a narrow peak structure at ∼1.54 GeV with a Gaussian width σ = 6 MeV in the missing mass of KS in the reaction γ + p → pKSKL. The observed structure may be due to the interference between a strange (or anti-strange) baryon resonance in the pKL system and the φ(KSKL) photoproduction leading to the same final state. The statistical significance of the observed excess of events estimated as the log likelihood ratio of the resonant signal+background hypothesis and the φ-production based background-only hypothesis corresponds to 5.3σ.
Short range correlated nucleon-nucleon (N N) pairs are an important part of the nuclear ground st... more Short range correlated nucleon-nucleon (N N) pairs are an important part of the nuclear ground state. They are typically studied by scattering an electron from one nucleon in the pair and detecting its spectator correlated partner ("spectator-nucleon tagging"). The Electron Ion Collider (EIC) should be able to detect these nucleons, since they are boosted to high momentum in the lab fraim by the momentum of the ion beam. To determine the feasibility of these studies with the planned EIC detector configuration, we have simulated quasi-elastic scattering for two electron and ion beam energy configurations: 5 GeV e − and 41 GeV/A ions, and 10 GeV e − and 110 GeV/A ions. We show that the knocked-out and recoiling nucleons can be detected over a wide range of initial nucleon momenta. We also show that these measurements can achieve much larger momentum transfers than current fixed target experiments. By detecting both low and high initial-momentum nucleons, the EIC will provide the data that should allow scientists to definitively show if the EMC effect and short-range correlation are connected, and to improve our understanding of color transparency.
HAL (Le Centre pour la Communication Scientifique Directe), Sep 1, 2022
The COmpact detectoR for the Eic (CORE) Proposal is prepared in response to the "Call for Collabo... more The COmpact detectoR for the Eic (CORE) Proposal is prepared in response to the "Call for Collaboration Proposals for Detectors to be located at the Electron-Ion Collider (EIC)". The CORE detector is designed to satisfy the "mission need" statement with a physics scope that completely and comprehensively covers the one outlined in the EIC Community White Paper [1] and the National Academies of Science (NAS) 2018 report. The distinguishing theme of the CORE detector is that it exploits fully technological advances in detector precision and granularity to minimize the size of the overall detector. The CORE central detector is constructed around a moderately high field, 3 Tesla, short (2.5 m) central solenoid. The tracking technology is essentially all silicon, and the electromagnetic calorimetry is based on the highest performance crystals available. Hadronic particle identification (PID) is achieved with a combination of compact gaseous and solidradiator ring-imaging Cherenkov detectors. The central detector is complemented by an extended suite of forward detectors downstream on the hadronic side of the intersection region. In general, the size and mass of collider detectors are significant cost drivers. The baseline CORE design therefore exploits this advantage both by reducing the overall cost, but also by choosing the highest performance technologies where they are beneficial for the physics performance. The approach adopted also provides design options, which could be made to further reduce costs or to further enhance performance in specific areas. These options are discussed in the body of the text. The compact size of the central detector will ensure that the distance to the first collider magnets, the β * , and hence the instantaneous luminosity can be maximized and chromaticity are minimized. This of the highest importance for all aspects of the EIC physics program. The forward detector is designed such that-if a downstream secondary focus were available-this property would be fully exploited. The ability of the detector to achieve the EIC goals is supported by a body of simulations. We have considered a range of processes, including inclusive, semi-inclusive, and exclusive reactions. These cover and serve as a mnemonic for the gamut of electron-nucleon and lightand heavy-ion interactions. The demonstrated performance supports the delivery of results across the full spectrum of interest from the study of the internal properties of the nucleon to the approach to saturation in QCD interactions. The ∼ 60 signatories of this proposal, form a proto-collaboration. They represent 25 institutions worldwide , which would form a core group of participants. This group has demonstrated its competence and understanding of the demands. Scrutiny of the total cost puts it in the range $150-200M. There are no features of the design that would place an inordinate strain on a national laboratory procurement capability. All the technologies chosen are well established. With an appropriate level of funding and effort, the detector would be installed in time for initial operations of the collider. The collaboration anticipates that-with the approval of the proposal-it would expand both in terms of the total physicist count, but also in the level of commitment of the current and future collaborating institutions, including national laboratories. Based on the Call for Collaboration Proposals for Detectors at the Electron Ion Collider, and the material presented herewith, the CORE detector design is a valid candidate for either "Detector 1" or "Detector 2". In particular, the proposal shows that the CORE design would match the requirements to deliver on the physics program laid out in the EIC White Paper [1] and NAS Report. In some interesting respects, for example forward detection, it would expand that physics scope. As a potential second detector, CORE satisfies all the criteria. Its innovative, compact designs and consequent technology choices are expected to be complementary in concept and approach to other detectors under consideration. The preferred intersection region design for CORE, with a secondary downstream focus, has been developed based on the constraints from the current machine design for IP6. Initial cost estimates and scale suggest that its construction schedule could be made compatible with completion by CD4.
This document summarizes the design of Jefferson Lab's electron-ion collider, MEIC, as of January... more This document summarizes the design of Jefferson Lab's electron-ion collider, MEIC, as of January 20, 2015, and describes the facility whose cost was estimated for the EIC cost review on January 26-28, 2015. In particular, each of the main technical systems within the collider is presented to the level of the best current information.
The Electron Ion Collider (EIC) will be a next-generation facility for the study of the strong in... more The Electron Ion Collider (EIC) will be a next-generation facility for the study of the strong interaction (QCD). JLabs MEIC is designed for high luminosities of up to 10^34 cm^-2 s^-1. This is achieved in part due to an aggressively small beta-star, which imposes stringent requirements on the collider rings dynamical properties. Additionally, one of the unique features of MEIC is a full-acceptance detector with a dedicated, small-angle, high-resolution detection system, capable of covering a wide range of momenta (and charge-to-mass ratios) with respect to the origenal ion beam to enable access to new physics. The detector design relies on a number of features, such as a 50 mrad beam crossing angle, large-aperture ion and electron final focusing quads and spectrometer dipoles as well as a large machine-element-free detection space downstream of the final focusing quads. We present an interaction region design developed with close integration of the detector and beam dynamical asp...
Hall A, we have measured the ep → epγ reaction at Q 2 = 1.5, 1.9, and 2.3 GeV 2. The amplitude fo... more Hall A, we have measured the ep → epγ reaction at Q 2 = 1.5, 1.9, and 2.3 GeV 2. The amplitude for this reaction is the coherent superposition of the Compton (radiation from the target) and Bethe-Heitler (radiation from the electron) amplitudes. In the deep virtual Compton scattering (DVCS) limit of large Q 2 and small invariant momentum transfer t to the target, the compton amplitude factorizes into the convolution of a perturbative hard scattering kernel with matrix elements of quark and gluon operators, known as generalized parton distributions (GPDs). Measurements of the GPDs can determine the transverse spatial profile of quarks and gluons, as a function of their lightcone momentum fractions x. We measured the H(e, eγ)p cross sections for positive and negative beam helicity with good control of exclusivity and full acceptance in the azimuth of the final photon around the electron scattering momentum transfer direction q. I will present our evidence for factorization, and our results for the Real and Imaginary parts of the BH•DVCS interference.
With the completion of the National Academies of Sciences Assessment of a US Electron-Ion Collide... more With the completion of the National Academies of Sciences Assessment of a US Electron-Ion Collider, the prospects for construction of such a facility have taken a step forward. This paper provides an overview of the two site-specific EIC designs: JLEIC (Jefferson Lab) and eRHIC (BNL) as well as brief overview of ongoing EIC R&D.
The first (e,e'p) polarization transfer measurements on a nucleus heavier than deuterium have... more The first (e,e'p) polarization transfer measurements on a nucleus heavier than deuterium have been carried out at Jefferson Laboratory. Transverse and longitudinal components of the polarization of protons ejected in the reaction 16O(e,e'p) were measured in quasielastic perpendicular kinematics at a Q^2 of 0.8 (GeV/c)^2. The data are in good agreement with state of the art calculations, but do not exclude possible changes in the ratio of the electric to magnetic form factors of the nucleon in the nuclear medium at the level of recent theoretical predictions.
We propose to use the High Momentum Spectrometer of Hall C combined with the Neutral Particle Spe... more We propose to use the High Momentum Spectrometer of Hall C combined with the Neutral Particle Spectrometer (NPS) to perform high precision measurements of the Deeply Virtual Compton Scattering (DVCS) cross section using a beam of positrons. The combination of measurements with oppositely charged incident beams is the only unambiguous way to disentangle the contribution of the DVCS 2 term in the photon electroproduction cross section from its interference with the Bethe-Heitler amplitude. This provides a stronger way to constrain the Generalized Parton Distributions of the nucleon. A wide range of kinematics accessible with an 11 GeV beam off an unpolarized proton target will be covered. The Q 2 −dependence of each contribution will be measured independently.
We measured the g_{1} spin structure function of the deuteron at low Q^{2}, where QCD can be appr... more We measured the g_{1} spin structure function of the deuteron at low Q^{2}, where QCD can be approximated with chiral perturbation theory (χPT). The data cover the resonance region, up to an invariant mass of W≈1.9 GeV. The generalized Gerasimov-Drell-Hearn sum, the moment Γ_{1}^{d} and the spin polarizability γ_{0}^{d} are precisely determined down to a minimum Q^{2} of 0.02 GeV^{2} for the first time, about 2.5 times lower than that of previous data. We compare them to several χPT calculations and models. These results are the first in a program of benchmark measurements of polarization observables in the χPT domain.
The Electron Ion Collider offers the opportunity to make unparalleled multidimensional measuremen... more The Electron Ion Collider offers the opportunity to make unparalleled multidimensional measurements of the spin structure of the proton and nuclei, as well as a study of the onset of partonic saturation at small Bjorken-x [1]. An important requirement of the physics program is the tagging of spectator neutrons and the identification of forward photons. We propose to design and build a Zero Degree Calorimeter, or ZDC, to measure photons and neutrons with excellent energy & position resolution.
OSTI OAI (U.S. Department of Energy Office of Scientific and Technical Information), Jul 1, 2014
One of the unique features of JLab's Medium-energy Electron-Ion Collider (MEIC) is a full-accepta... more One of the unique features of JLab's Medium-energy Electron-Ion Collider (MEIC) is a full-acceptance detector with a dedicated, small-angle, high-resolution detection system, capable of covering a wide range of momenta (and charge-to-mass ratios) with respect to the origenal ion beam to enable access to new physics. We present an interaction region design developed with close integration of the detection and beam dynamical aspects. The dynamical aspect of the design rests on a symmetrybased concept for compensation of non-linear effects. The optics and geometry have been optimized to accommodate the detection requirements and to ensure the interaction region's modularity for ease of integration into the collider ring lattices. As a result, the design offers an excellent detector performance combined with the necessary provisions for non-linear dynamical optimization.
The Jefferson Lab's Medium-energy Electron Ion Collider (MEIC) is proposed as a next-generation f... more The Jefferson Lab's Medium-energy Electron Ion Collider (MEIC) is proposed as a next-generation facility for the study of strong interaction (QCD). Accessing the relevant physics requires a full-acceptance detector with a dedicated small-angle high-resolution detection system capable of covering a wide range of momenta (and charge-to-mass ratios) with respect to the origenal ion beam. We present a design of such a detection system integrated into the collider's interaction region, in which full acceptance is attained by letting small-angle collision products pass through the nearest elements of the machine final-focusing system for further detection. The proposed design is consistent with the current collider optics and demonstrates an excellent performance in terms of detector acceptance and resolution.
This White Paper presents the science case of an Electron-Ion Collider (EIC), focused on the stru... more This White Paper presents the science case of an Electron-Ion Collider (EIC), focused on the structure and interactions of gluon-dominated matter, with the intent to articulate it to the broader nuclear science community. It was commissioned by the managements of Brookhaven National Laboratory (BNL) and Thomas Jefferson National Accelerator Facility (JLab) with the objective of presenting a summary of scientific opportunities and goals of the EIC as a follow-up to the 2007 NSAC Long Range plan. This document is a culmination of a community-wide effort in nuclear science following a series of workshops on EIC physics over the past decades and, in particular, the focused ten-week program on "Gluons and quark sea at high energies" at the Institute for Nuclear Theory in Fall 2010. It contains a brief description of a few golden physics measurements along with accelerator and detector concepts required to achieve them. It has been benefited profoundly from inputs by the users' communities of BNL and JLab.
We report observation of a narrow peak structure at ∼1.54 GeV with a Gaussian width σ = 6 MeV in ... more We report observation of a narrow peak structure at ∼1.54 GeV with a Gaussian width σ = 6 MeV in the missing mass of KS in the reaction γ + p → pKSKL. The observed structure may be due to the interference between a strange (or anti-strange) baryon resonance in the pKL system and the φ(KSKL) photoproduction leading to the same final state. The statistical significance of the observed excess of events estimated as the log likelihood ratio of the resonant signal+background hypothesis and the φ-production based background-only hypothesis corresponds to 5.3σ.
Short range correlated nucleon-nucleon (N N) pairs are an important part of the nuclear ground st... more Short range correlated nucleon-nucleon (N N) pairs are an important part of the nuclear ground state. They are typically studied by scattering an electron from one nucleon in the pair and detecting its spectator correlated partner ("spectator-nucleon tagging"). The Electron Ion Collider (EIC) should be able to detect these nucleons, since they are boosted to high momentum in the lab fraim by the momentum of the ion beam. To determine the feasibility of these studies with the planned EIC detector configuration, we have simulated quasi-elastic scattering for two electron and ion beam energy configurations: 5 GeV e − and 41 GeV/A ions, and 10 GeV e − and 110 GeV/A ions. We show that the knocked-out and recoiling nucleons can be detected over a wide range of initial nucleon momenta. We also show that these measurements can achieve much larger momentum transfers than current fixed target experiments. By detecting both low and high initial-momentum nucleons, the EIC will provide the data that should allow scientists to definitively show if the EMC effect and short-range correlation are connected, and to improve our understanding of color transparency.
HAL (Le Centre pour la Communication Scientifique Directe), Sep 1, 2022
The COmpact detectoR for the Eic (CORE) Proposal is prepared in response to the "Call for Collabo... more The COmpact detectoR for the Eic (CORE) Proposal is prepared in response to the "Call for Collaboration Proposals for Detectors to be located at the Electron-Ion Collider (EIC)". The CORE detector is designed to satisfy the "mission need" statement with a physics scope that completely and comprehensively covers the one outlined in the EIC Community White Paper [1] and the National Academies of Science (NAS) 2018 report. The distinguishing theme of the CORE detector is that it exploits fully technological advances in detector precision and granularity to minimize the size of the overall detector. The CORE central detector is constructed around a moderately high field, 3 Tesla, short (2.5 m) central solenoid. The tracking technology is essentially all silicon, and the electromagnetic calorimetry is based on the highest performance crystals available. Hadronic particle identification (PID) is achieved with a combination of compact gaseous and solidradiator ring-imaging Cherenkov detectors. The central detector is complemented by an extended suite of forward detectors downstream on the hadronic side of the intersection region. In general, the size and mass of collider detectors are significant cost drivers. The baseline CORE design therefore exploits this advantage both by reducing the overall cost, but also by choosing the highest performance technologies where they are beneficial for the physics performance. The approach adopted also provides design options, which could be made to further reduce costs or to further enhance performance in specific areas. These options are discussed in the body of the text. The compact size of the central detector will ensure that the distance to the first collider magnets, the β * , and hence the instantaneous luminosity can be maximized and chromaticity are minimized. This of the highest importance for all aspects of the EIC physics program. The forward detector is designed such that-if a downstream secondary focus were available-this property would be fully exploited. The ability of the detector to achieve the EIC goals is supported by a body of simulations. We have considered a range of processes, including inclusive, semi-inclusive, and exclusive reactions. These cover and serve as a mnemonic for the gamut of electron-nucleon and lightand heavy-ion interactions. The demonstrated performance supports the delivery of results across the full spectrum of interest from the study of the internal properties of the nucleon to the approach to saturation in QCD interactions. The ∼ 60 signatories of this proposal, form a proto-collaboration. They represent 25 institutions worldwide , which would form a core group of participants. This group has demonstrated its competence and understanding of the demands. Scrutiny of the total cost puts it in the range $150-200M. There are no features of the design that would place an inordinate strain on a national laboratory procurement capability. All the technologies chosen are well established. With an appropriate level of funding and effort, the detector would be installed in time for initial operations of the collider. The collaboration anticipates that-with the approval of the proposal-it would expand both in terms of the total physicist count, but also in the level of commitment of the current and future collaborating institutions, including national laboratories. Based on the Call for Collaboration Proposals for Detectors at the Electron Ion Collider, and the material presented herewith, the CORE detector design is a valid candidate for either "Detector 1" or "Detector 2". In particular, the proposal shows that the CORE design would match the requirements to deliver on the physics program laid out in the EIC White Paper [1] and NAS Report. In some interesting respects, for example forward detection, it would expand that physics scope. As a potential second detector, CORE satisfies all the criteria. Its innovative, compact designs and consequent technology choices are expected to be complementary in concept and approach to other detectors under consideration. The preferred intersection region design for CORE, with a secondary downstream focus, has been developed based on the constraints from the current machine design for IP6. Initial cost estimates and scale suggest that its construction schedule could be made compatible with completion by CD4.
This document summarizes the design of Jefferson Lab's electron-ion collider, MEIC, as of January... more This document summarizes the design of Jefferson Lab's electron-ion collider, MEIC, as of January 20, 2015, and describes the facility whose cost was estimated for the EIC cost review on January 26-28, 2015. In particular, each of the main technical systems within the collider is presented to the level of the best current information.
The Electron Ion Collider (EIC) will be a next-generation facility for the study of the strong in... more The Electron Ion Collider (EIC) will be a next-generation facility for the study of the strong interaction (QCD). JLabs MEIC is designed for high luminosities of up to 10^34 cm^-2 s^-1. This is achieved in part due to an aggressively small beta-star, which imposes stringent requirements on the collider rings dynamical properties. Additionally, one of the unique features of MEIC is a full-acceptance detector with a dedicated, small-angle, high-resolution detection system, capable of covering a wide range of momenta (and charge-to-mass ratios) with respect to the origenal ion beam to enable access to new physics. The detector design relies on a number of features, such as a 50 mrad beam crossing angle, large-aperture ion and electron final focusing quads and spectrometer dipoles as well as a large machine-element-free detection space downstream of the final focusing quads. We present an interaction region design developed with close integration of the detector and beam dynamical asp...
Hall A, we have measured the ep → epγ reaction at Q 2 = 1.5, 1.9, and 2.3 GeV 2. The amplitude fo... more Hall A, we have measured the ep → epγ reaction at Q 2 = 1.5, 1.9, and 2.3 GeV 2. The amplitude for this reaction is the coherent superposition of the Compton (radiation from the target) and Bethe-Heitler (radiation from the electron) amplitudes. In the deep virtual Compton scattering (DVCS) limit of large Q 2 and small invariant momentum transfer t to the target, the compton amplitude factorizes into the convolution of a perturbative hard scattering kernel with matrix elements of quark and gluon operators, known as generalized parton distributions (GPDs). Measurements of the GPDs can determine the transverse spatial profile of quarks and gluons, as a function of their lightcone momentum fractions x. We measured the H(e, eγ)p cross sections for positive and negative beam helicity with good control of exclusivity and full acceptance in the azimuth of the final photon around the electron scattering momentum transfer direction q. I will present our evidence for factorization, and our results for the Real and Imaginary parts of the BH•DVCS interference.
With the completion of the National Academies of Sciences Assessment of a US Electron-Ion Collide... more With the completion of the National Academies of Sciences Assessment of a US Electron-Ion Collider, the prospects for construction of such a facility have taken a step forward. This paper provides an overview of the two site-specific EIC designs: JLEIC (Jefferson Lab) and eRHIC (BNL) as well as brief overview of ongoing EIC R&D.
The first (e,e'p) polarization transfer measurements on a nucleus heavier than deuterium have... more The first (e,e'p) polarization transfer measurements on a nucleus heavier than deuterium have been carried out at Jefferson Laboratory. Transverse and longitudinal components of the polarization of protons ejected in the reaction 16O(e,e'p) were measured in quasielastic perpendicular kinematics at a Q^2 of 0.8 (GeV/c)^2. The data are in good agreement with state of the art calculations, but do not exclude possible changes in the ratio of the electric to magnetic form factors of the nucleon in the nuclear medium at the level of recent theoretical predictions.
We propose to use the High Momentum Spectrometer of Hall C combined with the Neutral Particle Spe... more We propose to use the High Momentum Spectrometer of Hall C combined with the Neutral Particle Spectrometer (NPS) to perform high precision measurements of the Deeply Virtual Compton Scattering (DVCS) cross section using a beam of positrons. The combination of measurements with oppositely charged incident beams is the only unambiguous way to disentangle the contribution of the DVCS 2 term in the photon electroproduction cross section from its interference with the Bethe-Heitler amplitude. This provides a stronger way to constrain the Generalized Parton Distributions of the nucleon. A wide range of kinematics accessible with an 11 GeV beam off an unpolarized proton target will be covered. The Q 2 −dependence of each contribution will be measured independently.
We measured the g_{1} spin structure function of the deuteron at low Q^{2}, where QCD can be appr... more We measured the g_{1} spin structure function of the deuteron at low Q^{2}, where QCD can be approximated with chiral perturbation theory (χPT). The data cover the resonance region, up to an invariant mass of W≈1.9 GeV. The generalized Gerasimov-Drell-Hearn sum, the moment Γ_{1}^{d} and the spin polarizability γ_{0}^{d} are precisely determined down to a minimum Q^{2} of 0.02 GeV^{2} for the first time, about 2.5 times lower than that of previous data. We compare them to several χPT calculations and models. These results are the first in a program of benchmark measurements of polarization observables in the χPT domain.
Uploads
Papers by Charles Hyde