Possible irradiation needs from CERN and requirements(a partial and selected view)M. Calviani (EN/STI)

Introduction

EN/STI group in charge of all beam intercepting devices at CERNTargets, collimator, dumps, stoppers, etc.Design, operation, maintenance, control, etc.

Wide range of energy deposition, peak, total, stresses, temperature

Materials ranging from graphite to tungstenDue to very high peak intensity (no CW-

beams), very significant dynamical stressesFew selected examples to follow…

AD-target Iridium target, subject to impact of 26 GeV/c

proton beam, 1.5*1013 p/pulse (400 ns)

Sudden increase of temperature >2000 °C in <0.5 ms

Few 1018 POT/y~0.3-4 DPA/y reached

Unknown mechanical properties in the hydrodynamic regime

HiRadMat

Study the dynamical responses of material under high intensity proton impact (collimator, targets, etc.)

O(1015 POT/experiment)

Dumps

Several new proton dumps (SPS, LHC, FCC) are under study or in the way to be studies

Possible needs of R&D on special 3D carbon-carbon or other novel ideas

Mechanical properties under irradiation are not precisely known

O(1 DPA) irradiation

Spallation targets (n_TOF)

20 kW Pb-based neutron white source

Present target lifetime foreseen ~10 years

New materials for the future spallation targets to improve physics reach and operational aspects

Mechanical properties of irradiated high-Z materials, O(0.5 DPA)

SHiP production target

Proposal for a new 400 kW production target for hidden particles searches

Hybrid TZM/W/W-(1.5%)TiC target, water cooled Significant thermal cycling (5*106), significant

pulse-by-pulse temperature excursion (250 °C)

SHiP material R&D example

Dose levels ~5*1021 n/cm2 (>0.1 MeV)Thermal cycling 25-150 C and 420 C, 5*106

cyclesTest campaign (examples):

Tensile and compression curves

Fatigue (Wohler-type curves in compression)

Fracture mechanics tests

Impact toughness to assess DBTT (Charpy tests)

Coating adherence following irradiation

Conclusions

Just a very rapid and very selected excursion of activities of interest for the STI group

Broad range of activities associated to materials R&D, both for dynamic response as well as long-term irradiation

We are definitely interesting in understanding the irradiation and PIE possibilities of LENA