Chapter 6: DUNE Detector Construction Management 6–60
Chapter 6
Chapter 6: DUNE Detector Construction Management 6–61
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Figure 6.1: A 10 kt DUNE FD SP module, showing alternating APAs, CPAs, FC and ground planes, detector support system, cryostat and cryogenics distribution.
Chapter 6: DUNE Detector Construction Management 6–62
detection systems (PD systems) are routed to the cryostat roof where they exit through a set of 75 feedthroughs. The cables are connected to warm interface boards (WIBs), which are contained in 150 warm interface electronics crates (WIECs) for APAs and 75 crates for PD systems. Data fibers from the WIECs carry the data to data acquisition (DAQ) racks inside the central utility cavern (CUC).
There are four high voltage (HV) feedthroughs on top of the cryostat, two on each end. In addition, there are feedthroughs for calibration, instrumentation and cryogenics distribution. Power supplies, and controls are located on top of the cryostat on a dedicated mezzanine. Cryogenics equipment is also installed on a separate mezzanine on top of the cryostat.
6.2 DUNE Dual-Phase Far Detector Module
Each DP module is a 10 kt LArTPC, contributing to the full 40 kt FD fiducial mass. One 10 kt DP module is shown in Figure 6.2.
Figure 6.2: A 10 kt DUNE DP module.
Each DP module is contained in a cryostat with the same internal dimensions as the SP module, but with some variations in cryostat penetrations. The DP module consists of a single drift volume with a vertical drift direction.
The drift volume is enclosed on the top by an array of 80 charge-readout planes (CRPs), on the bottom by cathode planes and on the perimeter by a FCs. It is 12.0 m in height with a 500 V/cm gradient. The cathode is held at a potential of −600 kV. The DP PD system consists of 720 photomultiplier tubes (PMTs) at the bottom of the drift volume and is integrated with the cathode planes. The LAr level in DP module is within the CRP, just above the collection grid and below the anode readout plane. A gradient of 2 kV/cm in this region is used to extract the drift electrons from the liquid. A large electron multiplier (LEM) with a gradient of 33 kV/cm causes
Chapter 6: DUNE Detector Construction Management 6–63
charge multiplication and amplification of the charge that is then collected on the anode, which consists of two perpendicular readout strips.
The DP DSS consists of a set of stainless steel cables that are suspended from feedthroughs on top of the cryostat. The cables can be extended to the floor of the cryostat where they are used to lift components to design height. In the case of CRPs, there are three cables per panel with active height control in order to position the panel precisely with respect to the LAr surface.
The cryogenic front-end (FE) electronics is installed in the signal feedthrough chimneys (SFT chimneys) on the roof of the cryostat to process the LArTPC signals. Each SFT chimney is coupled to a Micro Telecommunications Computing Architecture (µTCA) crate to digitize the signals. These crates are connected via optical fiber links to the DAQ back end. Arrangement of equipment on top of the cryostat is similar to the SP module.
6.3 DUNE Far Detector Consortia
A total of eleven FD consortia have been formed to cover the subsystems required for the two detector types currently under consideration. In particular, three consortia (SP-APA, SP-TPC Electronics and SP-Photon Detection) pursue subsystems specific to the single-phase design and another three consortia (DP-CRP, DP-TPC Electronics, and DP-Photon Detection) pursue designs for DP specific subsystems. An additional five consortia (HV System, DAQ, cryogenic instrumen- tation and slow controls (CISC), Calibration, and Computing) have responsibility for subsystems common to both detector technologies. Figure 6.3 shows the consortia associated with the FD construction effort along with their current leadership teams.
6.4 Work Breakdown Structure (WBS)
The complete scope of the DUNE construction project is captured in a work breakdown structure (WBS) to explain the distribution of deliverables between the consortia. In combination with interface documentation, the WBS is used to validate that all necessary scope is covered. The WBS is also used as a framework for building DUNE detector cost estimates.
The highest-level layers of the DUNE WBS are summarized in Figure 6.4. At level 1 the WBS is broken down into six elements corresponding to the five DUNE detector modules (four FD and one near detector (ND)) and technical coordination. The scope documented here is fully contained within the technical coordination, first FD module (SP), and second FD module (DP) level 1 elements.
For the FD module elements at level 1, the WBS breaks down at level 2 into elements encompassing the deliverables provided by each consortium to that detector module along with an element containing common deliverables associated with the required detector installation and integration
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Technical Coordination
-
E. James (TCN)---
S. Kettell (Deputy TCN)
SP APA
-
DAQ HV Systems-
DP CRPC. Touramanis (CL)A. Marchionni (TL) G. Lehmann Miotto (CL)A. Thea (TL) F. Pietropaolo (CL)B. Yu (TL) D. Duchesneau (CL)
SPTPC CISC Calibration DPTPC
Electronics
-
ElectronicsD. Christian (CL) s.Gollapinni (CL) J. Maneira (CL)
D. Autiero (CL)
A. Cervera (TL) K. Mahn (TL)
M. Verzocchi (TL) T. Hasegawa (TL)
SP Photon Computing DP Photon
Detectors
-
H. Schellman (CL)-
DetectorsE. Segreto (CL) M. Kirby (HL-TL) I. Gil Botella (CL)
D. Warner (TL) A. McNab (INT-TL) D. Duchesneau (TL)
Figure 6.3: DUNE consortia organization. CL refers to consortium leader and TL refers to technical lead.
effort. Since each consortium takes responsibility for a particular subsystem, this breakdown effectively corresponds to a division of deliverables across subsystems.
The level 3 breakdown of the level 2 subsystem WBS elements follow a common format that separates required activities into groupings defined roughly by their sequence in time. A total of six elements are used:
1. management,
2. physics and simulation,
3. design, engineering, and R&D, 4. production setup,
5. production, and
6. integration and installation.
The groupings at level 3 allow for the convenient separation of costs including those associated with one-time and recurring activities in the case where two identical detector modules are constructed.
Lower levels within these WBS elements are determined by the responsible consortia and generally
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