Neutron Detector Systems at ESS F. Mezei with R. Hall-Wilton Technical Coordinator Detector Group Leader www.europeanspallationsource.se Annual Review 2015

ESS consortium Host Countries of Sweden and Denmark 47,5% Construction 15% Operations In-kind Deliverables ~3% Cash Investment ~97% Non Host Member Countries 52,5% Construction 85% Operations In-kind Deliverables ~ 70% Cash Investment ~ 30%

Spallation sources: state-of-the-art SNS (Oak Ridge) 60 Hz proton pulse rate < 1 s pulse length 1 MW beam power  instantaneous power: 17 GW 1 GW Monolith liner Steel shielding

ESS: improved efficiency spallation source SNS (Oak Ridge) 60 Hz proton pulse rate < 1 s pulse length 1 MW beam power  instantaneous power: 17 GW 1 GW simplify Monolith liner Steel shielding ESS (Lund) 14 Hz proton pulse rate 2.8 ms pulse length 5 MW beam power  simpler, cost equivalent accelerator  instantaneous power: 0.15 GW

Scope & Budget & In-kind potential Total construction cost: € 1,843 billion (2013) Proton beam power: 5 MW Proton beam energy: 2 GeV User operation: 2023 (> 400 experiments/year) Target station € 154M Accelerator € 522M Instruments € 350M In-kind Cash

Performance: slow (< eV) neutron source brightness  = 3 Å h=3 cm, w=8 cm cold moderator TDR (2013) Conv. mod (2010) H2 p-H2 n 2x10 14 4x10 6x10  = 1.5 Å h=3 cm, w=8 cm thermal mod. optimal position Conv. &TDR (2013) ESS 5 MW, 3 cm flat moderator ESS 5 MW, TDR 2013 ISIS TS1 128 kW ISIS TS2 32 kW SNS 1 MW J-PARC 300 kW ILL 57 MW Performance: slow (< eV) neutron source brightness “Butterfly” bi-spectral moderator: cold, thermal “Butterfly “ bi-spectral moderator ESS pulse shapes ESS pulse shapes

ESS detector needs: quantities and resolutions 50 % of total In the presentation I will talk about Chopper system scope, Schedule, Budget risks and then I summarize it at the end arXiv:1411.6194

ESS detector needs: costs, availability, etc Other key parameters: - costs - availability - established reliability (>10 years) Other “good to have” parameters: - counting rate: up to 107 n/cm2/s - efficiency > 70 - 80 % Main issue: - 3He got rare after 911 - back, but more expensive 10 M€

Options and collaborations In the presentation I will talk about Chopper system scope, Schedule, Budget risks and then I summarize it at the end “Commercial-off-the-shelf” (made on command): strongly reduced share planned

Efficiency of Boron-10 Detectors Single layer is only ca.5% Multilayer configuration: still lower costs vs. 3He In the presentation I will talk about Chopper system scope, Schedule, Budget risks and then I summarize it at the end >50% @1.8Å JINST 8 (2013) P04020

10B demonstrator: quality, cheap coatings Mass production possible Done in Linkoping JAP 111 (2012) 104908 Coatings complete in June 104m^2 ca. 25k items <6 weeks coating time irradiation tests done: J. Rad. Phy. + Chem in press

10B demonstrator: quality, cheap coatings Mass production possible for large area Done in ILL 1 column (10 cm width) per week production rate once tooling is available

Thank you…