Horizon 2020 Framework Programme

HadronPhysicsHorizon
(HPH)

NextDIS

Challenges for Next Generation Deep Inelastic Scattering Facilities

Joint Research Activity

Activity Descriptive Title: / Challenges for next generation Deep Inelastic Scattering facilities
Activity Acronym: / NextDIS
Leading Institution: / CEA Saclay – Irfu/SPhN (France)
Name of spokesperson: / Franck SABATIE
E-mail: /
Telephone number: / +33169083206
Fax number: / +33169087584
Mobile: / +33645901171

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HadronPhysicsHorizon

PART B – Section 1. Excellence

1. Excellence

1.4 Ambition

HERA, the first and so far only electron-proton collider built at DESY, produced the largest ever database of Deep Inelastic Scattering (DIS) data. These data revealed the rich partonic structure of the proton, resulting in the much-improved knowledge of the unpolarized parton distribution functions. Recent experiments in various laboratories around the world (DESY, CERN, JLab, BNL, SLAC, KEK, etc.) and the parallel theoretical developments opened up the way to new fields of investigation and showed the importance of a comprehensive study of the parton dynamics, and in particular of the correlations between longitudinal and transverse degrees of freedom related for instance to partonic orbital momenta. Despite these outstanding achievements, there are still many compelling physics questions essential for understanding the fundamental structure of composite matter:

- How are the sea quarks and gluons, and their spins, distributed in space and momentum inside the nucleon?

- Where does the saturation of gluon densities set in at high energy?

- How does the nuclear environment affect the distribution of quarks and gluons and their interactions in nuclei?

These open questions will be answered by building a next-generation DIS facility, improving some/all of the following parameters: luminosity, center-of-mass energy, and polarization. Three major projects of high-energy e-p/e-A colliders are currently discussed worldwide: the Electron-Nucleon-Collider (ENC) project as a future upgrade to the upcoming FAIR facility in Germany, the Electron-Ion Collider (EIC) project in the US and the Large Hadron Electron Collider (LHeC) at CERN. The ENC foresees collisions of 3 GeV electrons with 15 GeV/c protons. The EIC plans to collide polarized electrons of up to 30 GeV with polarized protons of up to 250 GeV and ions up to 100GeV/u, whereas the LHeC is aimed at even larger center-of-mass energies with electrons of up to 140 GeV colliding with 7 TeV protons from the LHC. The former two are focused on the study of spin physics and on collisions involving nuclei, while the latter contains a rich Higgs, electroweak and BSM program, together with the exploration of the QCD structure of hadrons and nuclei at the largest possible energies.

The common requirement of large luminosity, orders of magnitude higher than at HERA, will enable unprecedented statistical precision in a great number of experimental observables. But this comes with a price that needs attention: systematic effects have to be controlled to a similar and ideally better level than statistical uncertainties. This performance can be achieved only by the use of realistic Monte Carlo Simulations, which are one of the important aspects of this work package. To match the precision and hermeticity specifications of next-generation DIS facilities, MC simulations must include a proper treatment of all the underlying sub-processes, hadronisation and radiative effects as well as the latest knowledge on transverse-momentum unintegrated, generalized, and ordinary parton distributions for both e-p as well as e-A scattering. These Powerful Monte Carlo tools will aid at refining the required detector parameters, especially Tracking and Particle Identification. R&D in these areas of instrumentation is the other important aspect of the work package, with developments of lightweight Micromegas trackers with associated Front-End electronics as well as studies of large-area RICH detectors. These two aspects of instrumentation are absolutely essential in order to get the maximum performance of next-gen DIS machines. In addition, this project plans to explore and validate with prototypes the potential applications of these advanced detectors in state-of-the-art medical imaging. Indeed, the development of innovative photon detection techniques, that allow large active areas at affordable costs, can find valuable applications in Nuclear Medicine and related fields. For instance, large-area optical photon detectors combined with innovative trackers (scatterer) are the essential components of a Compton Camera, one of the newest and most technologically complex devices in medical physics.

One last but essential aspect of this work package is to generate momentum and structure European research associated with the future DIS facilities such as the ENC, the EIC and the LHeC. There is no doubt that these machines represent an exciting future for hadronic physics worldwide but they have yet to develop a collaboration-like structure, especially in Europe. The NextDIS work package will foster closer links between the loosely connected current communities of DIS experimentalists and phenomenologists, an essential step towards the development of future international collaborations based around the LHeC, the ENC and the EIC facilities.

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HadronPhysicsHorizon

PART B – Section 2. Impact

2. Impact

2.1 Expected impact

Our research program is dedicated to have a large impact on the design of the future DIS facilities: ENC, EIC and LHeC. Detectors definition and design will be based on the Monte Carlo simulation tasks. The detector R&D tasks in this project examine some of the most important areas of such detectors: tracking and particle identification. Although the aim of this project is to prepare the future DIS facilities, most of the work will have direct applications to ongoing experimental programs at Jefferson Lab and COMPASS. One example is the R&D for large-area photon detection, which will have a significant impact on upgrades of the CLAS12 RICH detector at JLab and for the PANDA RICH detector at FAIR. Three areas of state-of-the-art technological developments concern our work package: large-area low-cost photon detectors, lightweight tracking detectors, very-front-end electronics for high capacitance detectors. Note that one of the strength of the Micromegas detector development lies in the tight collaboration with the ELVIA company (France), which is currently developing its capacity to produce large area and large quantities of such detectors using the bulk technology.

Thedevelopment of innovative detection techniques, that allow large active areasat affordable costs, can find valuable applications in Nuclear Medicine andrelated fields: Largearea optical photon detectors combined to innovative tracker (scatterer) are theessential components of the Compton Camera, one of the newest and mosttechnologically complexdevice in medical physics.

On the Monte-Carlo simulation side, methods and algorithms for all the theory foundations of our work will be developed in this program. Examples of high-impact items for the hadronic physics community include: fasts MC algorithms, TMD models, GPD models, QED/QCD higher-order corrections, all-order resummations of dominant higher-order contributions.

Finally, the NextDIS work package will further enhance the collaboration between non-European and European institutes: for the US-based EIC project in particular, there is a strong collaboration with Jefferson Lab and BNL for both Monte Carlo simulations and detector R&D. In addition there is an ongoing collaboration between JLab and FAIR on both detector technology and data analysis. The NextDIS work package constitutes an essential step towards the development of future European and international collaborations based around the LHeC, the ENC and the EIC facilities.

2.2 Measures to maximise impact

a) Dissemination and exploitation of results

As usual with fundamental physics activities, most of the dissemination involves publications and presentations at international conferences and workshops. In this work package, we plan on going a step further as the codes developed within the Monte Carlo tasks will be released as open source packages at a dedicated NextDIS web page. This is especially important since part of the work proposed here would have immediate applications already in current or near future DIS data analysis.

Our progress on instrumentation will also be published in peer-reviewed journals and likely used for the final design of detectors for the future DIS facilities.

b) Communication activities

Within this work package, we plan on organizing one of the next editions of the Electron-Ion Collider Workshop series (POETIC) in addition to a User Meeting on the same subject. The same web page, which will act as an open source repository for our Monte Carlo algorithms, will also be used as a communication tool in order to reach various types of audiences including the general public. One of the problem with hadronic physics is a difficulty to explain our activities and how they are linked to deep physics questions about the strong interaction. We plan on using the tools we developed in order to explain in simple terms the importance of our work. An crucial aspect of our proposal is the societal impact of the application of state-of-the-art detection techniques to the medical imaging field. Communication based on the applications to society will be used for the general public as it makes a direct link between fundamental activities and applied science.

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HadronPhysicsHorizon

PART B – Section 3. Implementation

3. IMPLEMENTATION

[Definitions:

‘Work package’ means a major sub-division of the proposed project.

‘Deliverable’ means a distinct output of the project, meaningful in terms of the project's overall objectives and constituted by a report, a document, a technical diagram, a software etc.

‘Milestones’ means control points in the project that help to chart progress. Milestones may correspond to the completion of a key deliverable, allowing the next phase of the work to begin. They may also be needed at intermediary points so that, if problems have arisen, corrective measures can be taken. A milestone may be a critical decision point in the project where, for example, the consortium must decide which of several technologies to adopt for further development.]

(maximum length: ½ page)

3.1.2 Timing of the different work packages and their components

Work package number / JRA29
Work package acronym / NextDIS
Work package title / Challenges for next generation deep inelastic scattering facilities
TASKS/Subtasks / 2015 / 2016 / 2017
Q1 / Q2 / Q3 / Q4 / Q1 / Q2 / Q3 / Q4 / Q1 / Q2 / Q3 / Q4
1. Monte Carlo Simulations for next generation DIS facilities
1.1 Exclusive final-state MC
1.2 Semi-inclusive final-state MC
1.3 QED and QCD radiative corrections
1.4 Nuclear modifications for exclusive and (semi-) inclusive MC gen.
2. Tracking for next generation DIS facilities
2.1 Lightweight Micromegas R&D (resistive, geometry, multiplexing)
2.2 Dedicated Front-End electronics R&D (very front-end, bonded chip)
3. Particle Identification for next generation DIS facilities
3.1 RICH detector studies (photo sensors, aerogel, integration)
3.2 Medical application (Compton Camera studies)

(Timelines are indicate in grey, milestones with black boxes)

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HadronPhysicsHorizon

PART B – Section 3. Implementation

Table 3.1a Work package Description

Work package number / JRA29 / Start date / 01/01/2015
Work package title / Challenges for next generation DIS facilities
Participant number / 1 / 2 / 3 / 4 / 5 / 6 / 7
Short name of participant / CEA / INFN / CNRS / UBirmingham / UPV-EHU / USC / UMainz
Person-months per participant / 68 / 134 / 42 / 9 / 6 / 6 / 18
Participant number / 8 / 9 / 10 / 11 / - / - / -
Short name of participant / UTuebingen / GSI / NCBJ / UYvaskyla / - / - / -
Person-months per participant / 18 / 63 / 18 / 6 / - / - / -
Objectives
HERA, the first and so far only electron-proton collider built at DESY, produced the largest ever database of Deep Inelastic Scattering (DIS) data. These data revealed the rich partonic structure of the proton, resulting in the much-improved knowledge of the unpolarized parton distribution functions. Recent experiments in various laboratories around the world (DESY, CERN, JLab, BNL, SLAC, KEK, etc.) and the parallel theoretical developments opened up the way to new fields of investigation and showed the importance of a comprehensive study of the parton dynamics, and in particular of the correlations between longitudinal and transverse degrees of freedom related for instance to partonic orbital momenta. Despite these outstanding achievements, there are still many compelling physics questions essential for understanding the fundamental structure of composite matter:
- How are the sea quarks and gluons, and their spins, distributed in space and momentum inside the nucleon?
- Where does the saturation of gluon densities set in at high energy?
- How does the nuclear environment affect the distribution of quarks and gluons and their interactions in nuclei?
These open questions will be answered by building a next-generation DIS facility. Their common requirement is a large luminosity, orders of magnitude higher than at HERA, which will enable unprecedented statistical precision in a great number of experimental observables. But this comes with a price that needs attention: systematic effects have to be controlled to a similar and ideally better level than statistical uncertainties.
The objectives of this WP are the following:
-  Monte Carlo Simulations: to match the precision and hermeticity specifications of next-generation DIS facilities, high-precision MC simulations must include a proper treatment of all the underlying sub-processes, hadronisation and radiative effects as well as the latest knowledge on transverse-momentum unintegrated, generalized, and ordinary parton distributions for both e-p as well as e-A scattering. These Powerful Monte Carlo tools will aid at refining the required detector parameters, especially Tracking and Particle Identification, which represent the other objectives of the WP. The progress in MC will also be used for the data analysis of present and near-future experimental data from HERA, HERMES, Jefferson Lab and COMPASS.
-  Tracking R&D: The central tracking in the barrel region of the detectors of the next-gen DIS facilities is of utmost importance for reaching the required momentum and vertex resolutions. For EIC, the standard choice consists of a TPC, but this choice has many difficulties especially at high luminosity. Recent developments in Micro-Pattern Gaseous Detectors (MPGDs) and especially in the Micromegas technology for the Jefferson Lab CLAS12 central detector (developed with the support of FP7) have shown that their use in a central tracking region is possible at a much reduced cost and material budget. The idea is to use bulk Micromegas detectors on thin 200 mm PCB. The advent of the resistive Micromegas technology and potential use of 2D-readout schemes make them an attractive low-cost alternative to the TPC or full-Si solutions proposed so far. We also plan on continuing the development of dedicated front-end electronics by adapting the DREAM chip to the collider environment.