Possible IDEA Topics for FP7

Stefan Schoenert

MPIK Heidelberg

Overview• JRA/NW

– Experimental benchmark tests for nuclear structure calculations: charge exchange experiments, muon capture, …. Or more fantastic: beta beams

– Improved screening facilities: Pushing the sensitivity of U-238 progenies (Ra-226 and below) and Th-228 progenies screening to the 1 Bq/kg limit (bulk) :

• Bulk contamination: array of germanium • Surface activities: large surface alpha counter (10 Bq/m^2)

– Active suppression methods to reach bgd index <10-4 cts/keV kg y in Germanium experiments

• Design study:– Few 10 meV scale:

• Funded experiments : Cuore, GERDA-I/II (III depending of physics results) • Funded R&D: Super-Nemo• New technology: Cobra, Edelweiss-type Ge,

design study for 1 meV scale? Is this too early?

Experimental benchmark tests for nuclear structure calculations: charge exchange

Dieter Frekers, Erice 05

Experimental benchmark tests for nuclear structure calculations: charge exchange

Dieter Frekers, Erice 05

Energy [keV] GeMPIHD-Moscow det. # 1-5

352 (U/Ra) 31 110 - 180609 (U/Ra) 30 96 - 140583 (Th) 23 18 - 422615 (Th) 17 5 11 - 221461 (K) 90 13 74 - 290100-2730 keV 9760 12300

GeMPIOperated at LNGS (3500 m w.e.)

background (peak) count rates [c/kg y]

From G. Heusser

Improved screening facilities

Two new systems built:GeMPI-2GeMPI-3

Array of GeMPI type of detectors ?

Cost: ~ 1MEuroMajor efforts:Underground machining facilitiesCNC, wire erosion, underground Crystal mounting and testing;Need to be lead by undergroundlaboratory

Surface screening detector

• Alpha counting with sensitivity of 1 alpha/day/m^2

• Dimension ~ 1m x 1m

• Not quite a BiPo detector as proposed for Super-Nemo

2: 1.332 MeV: Emax = 318 keV

1: 1.173 MeV

• T0 : crystal growing• 0.017 Bq/kg per day exposure• Test: detector production in 7.4 days • Assume 30 days 2.5 ·10-3 / (keV·kg·y)

• T0 : crystal growing• 0.017 Bq/kg per day exposure• Test: detector production in 7.4 days • Assume 30 days 2.5 ·10-3 / (keV·kg·y)

Active suppression methods to reach bgd index <10-4 cts/keV kg y in

Germanium experiments Example: Internal 60Co

2 kg

60Co background spectrum

1 2

1+ 2

Q

MC simulation

2 kg

60Co: suppression by segmentation

QMC simulation

2 kg

60Co: suppression by segmentation

~10 (7 seg.)Nseg = 1

QMC simulation

Nhit = 3

illustration: Simple 7-fold segmentation

60Co: suppression by LAr Ge-anticoinc.

~100LAr anticoinc.

Liquid Argon

QMC simulation

2 kg

60Co: segmentation and LAr Ge-anticoinc.

~1000

Liquid Argon

Nseg = 1AND

LAr anticoinc

Q

2 kg

MC simulation

Design study

Few 10 meV scale:• Funded experiments : Cuore, GERDA-I/II (III

depending of physics results) • Funded R&D: Super-Nemo• New technology: Cobra, Edelweiss-type Ge,

design study for 1 meV scale