THE DOUBLE-POLARIZED DD-FUSION EXPERIMENT + DETECTOR SYSTEM

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1 Petersburg Nuclear Physics Institute THE DOUBLE-POLARIZED DD-FUSION EXPERIMENT + DETECTOR SYSTEM P. Kravtsov for the PolFusion collaboration 1

both initial particles at 10-100 kev energy

2 The experiment goal Investigation of 4-nucleons reaction with polarization of the both initial particles at kev energy (center of mass). 3 He p d + d t + p 3 He + n d d t n 2

3 dd-fusion experiments Unpolarized beam, unpolarized solid target Unpolarized beam, unpolarised gas target Polarized beam, unpolarized solid target Polarized beam, unpolarized gas 3

The Quintet suppression factor QSF 1,1 0 1 9 2 0

4 The Quintet suppression factor QSF 1, ,1 4 1,0 0,0 2 1, 1 Direct experiment required! 4

PolFusion collaboration Petersburg Nuclear Physics Institute, Russia Forschungszentrum Jülich, Germany Cologne University, Germany University ITMO, St.

5 PolFusion collaboration Petersburg Nuclear Physics Institute, Russia Forschungszentrum Jülich, Germany Cologne University, Germany University ITMO, St.Petersburg, Russia ABS, CELGAS students Polarimetry PolFusion POLIS KVI, Gronningen, Netherlands ABS Detector POLIS Exp. Hall Polarimetry Ferrara University, Italy Financial support: RSF ( ) 5

6 The layout of the experiment 3 2+ He (0.8 MeV), 3 H + (1.0 MeV) d 0 (0.1 ev) ABS Ferrara (IUCF) ABS 16 I ~ 4 10 a t/s Target density ~ a t/cm Vector polarization: ± dd-polarimeter or LSP 25 2 Luminosity: /cm s count rate: ~ 120/h (30keV) 3 week beam time (60000 events) d 3 0 He d d 3 H d 0 (0.1 ev) LSP 2 n p Lamb-Shift Polarimeter e e d (1-32 kev) n (2.4 MeV), p (3.0 MeV) Ion source Polarized Ion Source Ion beam: I = 20 μa ( d/s) E beam = 32 kev Vector polarization: ± 0.7 6

7 Polarized ion source (POLIS) POLIS Ion current at the source up to 20uA Magnets power supplies Vacuum system problems Unstable beam New ionizer for energy up to 100keV 7

8 POLIS. New ECR Ionizer Atomic beam High voltage (100kV) Microwave 2.45GHz ~200W Uniform magnetic field (875G) Gradient magnetic field Helium for plasma ignition 8

9 Polarized atomic beam source (ABS) Ferrara ABS Dissociator upgrade Nozzle cooling Control system Vacuum system RF transition units 9

10 ABS nozzle cooling Stable temperature down to 55K 10

11 ABS. Dissociator upgrade New schematic for better matching with generator Geometry optimization of RF circuit Reflected power decreased from 150W to 3W Two-channel RF matchbox with splitter to feed both dissociators from single generator 11

12 Polarimetry Normal operation POLIS Tuning ABS ABS POLIS Detector Deflector POLIS LSP Ioniser NRP LSP 12

13 Polarimetry. LSP ionizer Magnets (1000G) Extractor and focusing Ionizer cell Cathode 13

14 Polarimetry. LSP Na cell 14

15 Polarimetry. Deflector for NRP 15

16 Analysis The observables in the d+d -> 3 He+n and d+d-> 3 H+p reactions with polarized deuterons 16

17 Detector system design Readout electronics connectors Helmholtz coils NdFeB permanent magnets Detector system Detector chamber 17

18 Magnetic field, G Magnet system B =300 G = 2.5 Bc Magnet field is generated by 24 permanent magnets with dimensions 80х40х10 mm 3 with pole tip field of 1.25 T at the surface (NdFeB N40) Btotal Btransverse Axis coordinate, mm 18

active area: 1 cm 2 depleted layer: 300 um energy resolution: <50keV low

19 Detector system. PIN diodes version. 4- detector with 51% filling 576 Hamamatsu PIN-diodes (S ) PIN-diode active area: 1 cm 2 depleted layer: 300 um energy resolution: <50keV low reverse voltage (<=50V) Square detector elements (4x4 diodes) Standard PCB assembly with spring through-hole mounting (no solder!) 19

20 Simulation of the detector system 20

Turbopump Forepump Alpha-source: 239 Pu + 240 Pu =

21 PIN-diodes test bench Preamplifier Vacuum chamber Detector Bleeding valve O scilloscope a H 2 PC Turbopump Forepump Alpha-source: 239 Pu Pu = 80.4% 238 Pu Am = 19.6% 234 U U U 241 Am 21

22 PIN diode test measurements Dead layer thickness measurement (D 1μm) P. Monich. Bachelor thesis (ITMO university). Active area uniformity tests Inhomogeneity <0.5% for the whole active area Hydrogen vacuum performance Better 0.16% stability at hydrogen pressure of 10-4 mbar. Expected vacuum in the experiment mbar. 22

23 Detector system assembly 23

Readout electronics Readout requirements: 600 channels Total count rate 1kHz

) Event synchronization for coincidence trigger CSP from ATLAS CSC [BNL]

IEEE Nuclear Science Symposium Conference Record (2005) 48 channel Waveform

24 Readout electronics Readout requirements: 600 channels Total count rate 1kHz Standard interface (Ethernet?) Event synchronization for coincidence trigger CSP from ATLAS CSC [BNL] Junnarkar et al. IEEE Nuclear Science Symposium Conference Record (2005) 48 channel Waveform digitizer (WFD) Concentrator Detector ADC FPGA FPGA 2x24-channel CSP Charge Sensitive Preamplifier + Shaper ASF-48 6 x 8-channel pipeline ADC 12 bit, 65MHz Self-triggered WFD 12 bit resolution count rate up to 50 khz 24

25 ASF48 readout board 25

26 Readout signal processing Benefits Precise analytical fit No baseline dependence Best resolution (<=5LSB) 26

27 Energy resolution Test pulse E=1000keV RMS=0.49%=4.9keV (15 kev with cable and C det =40pF) 27

28 Signal quality Signal quality checks: ADC range clipping Signal shape (derivatives) Peaks position 28

29 Solid target experiment Target: deuterated polymethylmethacrylate Deuteron beam 15keV ~5uA А. Васильев 29

30 Solid target results He t p

31 Full scale readout electronics (ASF-48) Concentrator CROS3 Power distributor (5V 40A) ASF48 (12+1) 31

32 Optimizations (grounding, pickups ) 32

33 Data acquisition software ASF48 test software Full scale DAQ software based on MIDAS (Maximum Integrated Data Acquisition System) Flexible distributed DAQ system Web interface for run control and monitoring Data transfer / logging capability Online data monitoring Online database Message logging Alarms 33

34 Data acquisition software 34

35 Thank you! 35

36 36

37 BACKUP 37

38 Hyperfine states ABS 85% value HFS after HFS after MFT Sextupole 1 Sextupole 2 SFT WFT HFS after ABS Pz Pzz Pz Pzz Beam 1, 2, , 2, , 2, 3 +1/3-1/ , 2, , , , 2, , , 2 +2/ , 2, , on 3, 4-2/ , 2, , , 6 +5/ , 2, , , 6 +1/ , 2, , , 5-1/ HFS after Sextupole 1 MFT HFS after Sextupole 2 POLIS 75% value SFT WFT HFS after ABS Pz Pzz Pz Pzz Beam 1, 2, , 2, , 2, , 2, , , , 2, , , , 2, , on 3, , 2, , , , 2, , , , 2, , ,

39 , mb Unpolarized cross sections 10 2 H d, n 3 He 2 H d, p 3 H Ed, kev R. E. Brown, N. Jarmie, Phys. Rev. C 41 N4 (1990) 39

Experiment POLFUSION

Petersburg Nuclear Physics Institute National Research Center "Kurchatov Institute" Experiment POLFUSION A. Vasilyev for PolFusion collaboration 1 Collaboration Petersburg Nuclear Physics Institute, Russia