SoLID Magnet - Engineering and Cost Robin Wines, JLAB SoLID Director’s Review 2015

Magnet - Engineering & Costs Experiment Requirements CLEO-II Solenoid Magnet Hall A Layout Analysis Magnet Modifications Costs and Project Manpower Status and Strategic Plan

Experiment Requirements SoLID requires a magnet to produce a uniform, symmetric field primarily in the direction of the beam; ideal choice of solenoid. The magnetic field is utilized for tracking and background shielding The spectrometer requires: large acceptance in polar angle of 8° to 24° for SIDIS and 22° to 35° for PVDIS, azimuthal angle of 2π, and momentum resolution of 2% from 1 to 7GeV The Solenoid has integral field requirement of 5 T-m, length of 3-4 meters with outer diameter limit of 3 meters and clear bore diameter of 2.9 meters.  

CLEO-II Solenoid Considered several magnets for SoLID. The CLEO-II from Cornell found to be the best solution CLEO-II is a superconducting solenoid magnet fabricated in 1989 and operated through 2008. The magnet remains housed in the Cornell facility. Jlab magnet and cryo engineers visited Cornell in 2014 to discuss operational history and transport of CLEO-II. Agreement in place to begin disassembly and transport of the magnet with oversight by Jlab in 2016. The magnet has good stability, low cryogenic heat load, passive cooling, and passive protection. Operational History: Cryostat has remained sealed from fabrication, 4 noted quenches with no change in functionality, only modification in cryogen controls and new power supply

CLEO-II Solenoid Magnet Type Solenoid Number of turns in coil 1281 PARAMETER DESIGN VALUE Magnet Type Solenoid Number of turns in coil 1281 Coil Structure 3 sections of 2 layer helical wound in 8 welded lengths Conductor 5 mm x 16 mm Aluminum stabilized, 11 strand Cu-Nb-Ti Nominal Current (A) 3266 Current Density (MA/m) 1.2 Operating Field (Tesla) 1.5T Field Integral BdL (T-m) 5 Outer Diameter (m) 3 Clear Bore (m) 2.9 Length (m) Coil = 3.5, Cryostat = 3.8 Inductance (H) 4.6 Stored Energy (MJ) 25 Cooling Mode 700 liter liquid Helium dewar using thermal-syphon circulation Insulation high vacuum, liquid Nitrogen cooled radiation shield, superinsulation

CLEO-II Solenoid Cryostat sealed by o-rings between coil collars. Coil forces and coil collars balanced with 4 rods. Return Yoke constructed of 3 layers of 36 cm thick iron, pieced in 8 sectors each.

CLEO-II in Hall A Hall A truck ramp - 1st verified cryostat fits down truck ramp into Hall A 17’ height (5.2m) 6” rollers

CLEO-II in Hall A HRS Target Pivot SoLID HRS Pivot to target -115 cm Target to center of Solenoid – 350 cm SoLID Spectrometer – 730 cm

CLEO-II in Hall A HRS-L SoLID 28’ 58’ HRS-R 82’ Truck Ramp

SoLID Solenoid Return Yoke End cap Donut Coil End cap Bottom Front Cap Coil Collar End cap Nose Coil Collar

SoLID Solenoid Analyzed magnet in 2D POISSON Added End cap, design optimized to function as field clamp, shielding and support for detectors. Kept 8 to 15cm clearance of acceptance from End cap Acceptance angle requirements define need for modification to downstream coil collar Only 2 of 3 yoke return layers needed, allowing fit into Hall A beam line PVDIS 36o PVDIS 21o SIDIS 26o SIDIS 14.7o SIDIS 8o SIDIS 2o PVDIS 3.5o

SoLID Solenoid – Field Data Bz is 1.4 T at center and 0.8 T at exit of coil End cap Donut Collar Upstream Return Yoke End cap Bottom Collar Downstream Coil Front Cap shield End cap Nose

SoLID Solenoid - Field Data B at nominal Cerenkov photon sensor location are around 120G and 50G B at SIDIS forward angle EC photon sensor location is below 100G B at PVDIS forward angle EC photon sensor location is below 500G B > 100G

SoLID Solenoid - Forces Modifications change resultant forces on coil Force direction changes at circled areas Net force on yoke and coils balanced by adjusting location of Front Piece where force varies from 3-5 t/cm (axial force) Radial force acceptable as 30 MPa on Aluminum cryostat, yield of Aluminum at 100 MPa -20.3 171.2 122.9.4 -269.0 8.1 0.7 -238.4 110.2 108.6 -119.2 305.4 6.3 -316.5 -79.6 0.008 0.2 165.5 0.7 0.2 38.9 0.04

Magnet Modifications RETURN YOKE 2 of 3 layers of return yoke needed, keeping saturation under 2 T, allows fit of magnet on Hall A beam line Sectors to be machined to shorten them by 75cm to allow fit of downstream coil collar and endcap. $360k for diamond wire cutting of 24 pieces Return Yoke

Magnet Modifications Coil Collars Upstream coil collar reused from CLEO-II Downstream coil collar to be modified or replaced to allow acceptance angle clearance $500k to replace downstream coil collar and hardware Coil Collar

Magnet Modifications FRONT CAP New pieces to balance forces , provide shielding and field clamp Front cap consists of 16’ diameter x 1.3’ thick plate plus 1.5” plates adjustable for shielding $677k for new fabrication based on 75 tons of steel Front Cap

Magnet Modifications END CAP New pieces required to support detectors, provide field clamp and shielding Fabrication in parts; donut, bottom and nose Parts to split vertically to allow access to detectors 19’ diameter x 0.5’ thickness $1535k for machining 6 parts, based on 152 tons of thick steel and hardware End cap donut End cap bottom End cap nose

Magnet Cost and Labor K$ & FTE Estimates based on volume of material, size machines to handle and Hall D experience

CLEO-II Transport Plan Items available from Cornell: Superconducting magnet, Octagonal iron shielding, Magnet transport frame/cradle, Dynapower DC power supply, Valve control box, Cryogenic bayonets, Data acquisition, Rotation/turning jigs, Steel mounting blocks, Third iron layer steel, plate to support the 700 liter dewar,700 liter dewar, Transfer lines, Readout boxes for strain gauge Disassembled and loaded on trucks for shipping by the Cornell personnel with oversight by Jefferson Lab. It will require 52 trucks to transport the magnet and related equipment. We have identified all of the parts of the CLEO magnet, with sizes and weights, anticipating a need for storage of these parts at Jefferson Lab starting Summer 2016, total weight of 860 tons. The cryostat (16 tons) and power supply will need to be stored in an environment-controlled area of approximately 400 square feet. Jefferson Lab projects the use of the CMSA site for storage of all parts.

Magnet Status 2D POISSON analysis gives preliminary solution of modifications to allow use of CLEO-II Solenoid for SoLID. 3D analysis to be completed in FY15-FY16 to verify design of new parts and quantify the performance parameters of the magnet. Inspection of CLEO-II Solenoid indicates magnet is functional and suitable for use in Hall A. Agreement with Cornell to transfer magnet to JLAB. JLAB preparing for transport to begin in Summer of 2016. Hall A Engineering continues collaboration on magnet and detectors in bi-weekly meetings.

Backup

Cost and Labor Currently, Hall A has manpower of : 2 engineers, 3 designers, 2 engineering associates and 4 technicians. Additional resources to be available within Jlab and through contracting. Hall D magnet and installation similar to SoLID requirements. Hall D labor experience over 3-4 years: Magnet- 5FTE/year Infrastructure- 4FTE/year, Platforms and Supports – 1FTE/year Control System – 2FTE, $400k Steel machining estimated as $4/lb to $6 /lb based on material weight, size and amount of machining. Values taken from recent procurements. Additional $240k plus 5 FTE is costed for disassembly and transport of CLEO-II to Jlab. Cornell to provide labor with oversight by Jlab. Preliminary installation estimate requires 1.5 years for full installation and 14.2 FTE of labor

Hall A Floor Loading 500 ton 500 ton 250 ton SoLID magnet and detectors encompass an area of 5.8 meters in diameter and 7.3 meters long. Clearance to the Hall floor ranges from 10 to 38 cm, sufficient for support. Weight of the CLEO-II magnet, detector hut and detectors is 1300 tons. The floor in this installation region is designed for 250 tons for a 12 square foot pad. SoLID footprint 500 ton 28’ 250 ton 82’ 58’

Magnet Interactions and Field Uniformity A TOSCA calculation was done to study SoLID + Polarized target magnets interactions Forces between magnets are manageable About ~7.7 ton on iron plate in front of SoLID due to 5T coils About ~0.25 ton on the target coil due to SoLID Target and SoLID support structure design will take this into consideration Recent experience with g2p/GEp experiment: Used 5 T polarized target + pair of septum magnets close to target No major problem due to magnet forces Courtesy, R. Wines Field uniformity along the 3 cm target

Cost and Labor for Detector Supports and Hall Infrastructure

CLEO II in Hall A