project simple for dark matter search
DESCRIPTION
Project SIMPLE for Dark matter search. The Group. USA H. S. Miley (PNNL) J. I. Collar (Chicago). PORTUGAL T. A. Girard (CFN) T. Morlat (CFN) F. Giuliani (CFN) M. Felizardo (CFN/ITN) R. Ramos (CFN/ITN) J. G. Marques (CFN/ITN). FRANCE G. Waysand (CNRS) D. Limagne (CNRS). - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: Project SIMPLE for Dark matter search](https://reader036.vdocument.in/reader036/viewer/2022062422/56813f50550346895daa0c01/html5/thumbnails/1.jpg)
Project SIMPLE for Dark matter search
FRANCE
G. Waysand (CNRS)
D. Limagne (CNRS)
PORTUGAL
T. A. Girard (CFN)
T. Morlat (CFN)
F. Giuliani (CFN)
M. Felizardo (CFN/ITN)
A. R. Ramos (CFN/ITN)
J. G. Marques (CFN/ITN)
USAH. S. Miley (PNNL)
J. I. Collar (Chicago)
The Group
![Page 2: Project SIMPLE for Dark matter search](https://reader036.vdocument.in/reader036/viewer/2022062422/56813f50550346895daa0c01/html5/thumbnails/2.jpg)
The search for Dark Matter
Dark Energy : 67 6 %
supernovae observations
Cold Dark Matter29 4 %inference from galaxy dynamics
baryons : 4 1 %direct observation,
inference from
elemental abundances NBBlm
m
1
~70%~30%
~1% ~4%~25%
![Page 3: Project SIMPLE for Dark matter search](https://reader036.vdocument.in/reader036/viewer/2022062422/56813f50550346895daa0c01/html5/thumbnails/3.jpg)
Dark Mater candidate: Neutralino
→ Lagrangian : elastic scattering of a generic WIMP (spin ½) on nucleon :
J
JSaSaG nnppAfA
1)(
32 222
2222 )(4
ANgZgG npAFA
Spin dependent channel
Spin INdependent channel
Target = heavy atom
Target = ?
)()(24 nngppgnnappaGL npnpF
![Page 4: Project SIMPLE for Dark matter search](https://reader036.vdocument.in/reader036/viewer/2022062422/56813f50550346895daa0c01/html5/thumbnails/4.jpg)
ppAA
pA
Ap CC /
12
2limlim
pnAA
nA
An CC /
12
2limlim
Spin dependent channel
→ Cross section (limite) would reach a maximum, depending on (Ref. Tovey et al, PLB 488 (2000) 17):
*Proton sensitive: (WIMP independent model)
*Neutron sensitive: (WIMP independent model)
2,,
, 13/4/
npnp
npA S
J
JCC
![Page 5: Project SIMPLE for Dark matter search](https://reader036.vdocument.in/reader036/viewer/2022062422/56813f50550346895daa0c01/html5/thumbnails/5.jpg)
To detect the beast
Requirements:
→ Cross section max in the spin dependent :
→ Cross section max in the spin Independent: Heavy atom Target (Xe, I…)
→ Detector with low recoil energy 1-100 KeV
→ Problem of background for direct detection: Low rate of event < 1 event/kgd: Shielding for the background (µ, e-, γ…)
Fluorine
(proton sensitive)
Xe, Ge
(neutron sensitive)
![Page 6: Project SIMPLE for Dark matter search](https://reader036.vdocument.in/reader036/viewer/2022062422/56813f50550346895daa0c01/html5/thumbnails/6.jpg)
The Superheated Droplet Detector (SDD)
→ Have low critical energy (e.g. Ec=8keV at {T=9ºC, p=2bar} for C2ClF5)
→ High Fluorine content (C2ClF5, C3F8, C4F8, C4F10...)
→ The gradient condition: blind to backgrounds(, , …) only neutron & alpha
( )
( )
c
c
c
E E
E TdE
dx L T
![Page 7: Project SIMPLE for Dark matter search](https://reader036.vdocument.in/reader036/viewer/2022062422/56813f50550346895daa0c01/html5/thumbnails/7.jpg)
keVEF 1312
( )
( )
c
c
c
E E
E TdE
dx L T
T(C)
C2ClF5 (R115)
![Page 8: Project SIMPLE for Dark matter search](https://reader036.vdocument.in/reader036/viewer/2022062422/56813f50550346895daa0c01/html5/thumbnails/8.jpg)
Description of the SIMPLE SDD
→ Refrigerant : C2ClF5 (R115) under droplets (<r>~ 30 μm)
→ Matrix (food products):
• Gelatine (1.8%) : pig skin and not bones: low content in Ca & K• Bidistilled water (16%)• Polyvinylpyrrolidone PVP (3.6%) : to decrease solubility of freon • Glycerine (78.6%) : matching density, high mouillability (no spurious
event on the walls)
![Page 9: Project SIMPLE for Dark matter search](https://reader036.vdocument.in/reader036/viewer/2022062422/56813f50550346895daa0c01/html5/thumbnails/9.jpg)
Purification of the matrix
Purification of food products: well known in the food industry.
Purification of the ingredients with M+ MP500 Lewatit resin for metal extraction (anionic exchange resins).
Filtration system with acropack filter 0,2 microm.
→ radiocontamination < 0.5events/(kgfreon)/d
Purification by resins of glycerine, gelatine & PVP Filtration of the gelatine+PVP
![Page 10: Project SIMPLE for Dark matter search](https://reader036.vdocument.in/reader036/viewer/2022062422/56813f50550346895daa0c01/html5/thumbnails/10.jpg)
Suspension fabrication
10g
![Page 11: Project SIMPLE for Dark matter search](https://reader036.vdocument.in/reader036/viewer/2022062422/56813f50550346895daa0c01/html5/thumbnails/11.jpg)
![Page 12: Project SIMPLE for Dark matter search](https://reader036.vdocument.in/reader036/viewer/2022062422/56813f50550346895daa0c01/html5/thumbnails/12.jpg)
The shielding for SIMPLE
Faraday cage
EM noise
LSBB, Rustrel
500m of montain = 1500 m.w.e ~ 2 km of tunnel
Neutron flux from rock: 4 10-5 n/cm2.s
Ambiant muon flux ~ 0.5 10-3 /m2.s
Radon ~ 28 Bq/m3
Hz
fT2
![Page 13: Project SIMPLE for Dark matter search](https://reader036.vdocument.in/reader036/viewer/2022062422/56813f50550346895daa0c01/html5/thumbnails/13.jpg)
Dark Matter : the set up for SIMPLE
Installation of the SDDs inside the pool
Temperature T=8.9ºC
3.0
bc
b
TT
TTs
For s>0.5 then sensitive to X-rays, α-rays and cosmics ray muons.
![Page 14: Project SIMPLE for Dark matter search](https://reader036.vdocument.in/reader036/viewer/2022062422/56813f50550346895daa0c01/html5/thumbnails/14.jpg)
Results of 0.42 kgd exposure(42 g @ 10 day)
Main background:
*Leaks from the cap ~ 30/kgd
*Neutrons < 3/kgd
*Alpha < 0.5/kgd
*radon < 1/kgd
pA
p
A
pA
Ap C
C2
2limlim
From experiment
Ref: T. A. Girard et al, PLB 621 (2005) 233
![Page 15: Project SIMPLE for Dark matter search](https://reader036.vdocument.in/reader036/viewer/2022062422/56813f50550346895daa0c01/html5/thumbnails/15.jpg)
22
2
lim)lim( 24 pFA
n
n
Ap
p
G
aa
22nnpP aaaa
Ref: T. A. Girard et al, PLB 621 (2005) 233
npA
np
A
npA
Anp C
C,
,
2
2,limlim
,
lim2
AnA
pAA
+
npAAF
npA CG ,22, 4
![Page 16: Project SIMPLE for Dark matter search](https://reader036.vdocument.in/reader036/viewer/2022062422/56813f50550346895daa0c01/html5/thumbnails/16.jpg)
Near futur: Tasks for nov 2006 (3kgd)
Improvements to do, from the last experiment (0.42kgd): short exposure (10d) : increase the lifetime of the SDD,
how?
Leak : resolve the leak problem from the caps : change the “Mc Gyver cap” into something more professional
Acoustic, reduce the electronic background noise
![Page 17: Project SIMPLE for Dark matter search](https://reader036.vdocument.in/reader036/viewer/2022062422/56813f50550346895daa0c01/html5/thumbnails/17.jpg)
Increase the lifetime, how ?
Droplet: by recompression
Interface droplet-matrix : surfactant as shielding against Oswald ripening effect droplet too small+ possibility of foam = loss of efficiency
Matrix: additives - increase the fracture energy ? Delayed the formation of fractures
![Page 18: Project SIMPLE for Dark matter search](https://reader036.vdocument.in/reader036/viewer/2022062422/56813f50550346895daa0c01/html5/thumbnails/18.jpg)
Fracture experiment
Refs: Y. Tanaka et al, Eur. J. Phys. E 3 (2000) 395
T. Morlat et al, NIMA 560 (2006) 339
![Page 19: Project SIMPLE for Dark matter search](https://reader036.vdocument.in/reader036/viewer/2022062422/56813f50550346895daa0c01/html5/thumbnails/19.jpg)
Result with additives
PEG: no because of crystallisation of the glycerine
Agarose: increase resistance to fracture + Shift the Tsol-gel
T. Morlat et al, NIMA 560 (2006) 339
![Page 20: Project SIMPLE for Dark matter search](https://reader036.vdocument.in/reader036/viewer/2022062422/56813f50550346895daa0c01/html5/thumbnails/20.jpg)
Leaks from the cap ?
BEFORENOT ANYMORE !!!
![Page 21: Project SIMPLE for Dark matter search](https://reader036.vdocument.in/reader036/viewer/2022062422/56813f50550346895daa0c01/html5/thumbnails/21.jpg)
The solution
AFTER
![Page 22: Project SIMPLE for Dark matter search](https://reader036.vdocument.in/reader036/viewer/2022062422/56813f50550346895daa0c01/html5/thumbnails/22.jpg)
The sound acquisition for nov 2006
0.022 0.023 0.024 0.025 0.026 0.027 0.028 0.029 0.03 0.031-1.5
-1
-0.5
0
0.5
1
(s)
(V)
Test in Rustrel : background noise down to 0.95mV
Piezoelectric Transducer
Preamplifier Data Acquisition
BEFORE
AFTER
Noise: 100-200mV
![Page 23: Project SIMPLE for Dark matter search](https://reader036.vdocument.in/reader036/viewer/2022062422/56813f50550346895daa0c01/html5/thumbnails/23.jpg)
What we expect for the 3kgd (nov. 2006)
Agarose to increase the time of exposure (40 days)
New cap: no leaks in 3 weeks under presure
New electronic with low background noise
7 “fresh SDDs” (~80 g), fabrication in Rustrel (no transportation)
![Page 24: Project SIMPLE for Dark matter search](https://reader036.vdocument.in/reader036/viewer/2022062422/56813f50550346895daa0c01/html5/thumbnails/24.jpg)
New limit projected
-10
-5
0
5
10
-8 -6 -4 -2 0 2 4 6 8
an
NAIAD(3879 kgd)
-10
-5
0
5
10
-8 -6 -4 -2 0 2 4 6 8
CDMS(19kgd)
-10
-5
0
5
10
-8 -6 -4 -2 0 2 4 6 8
EDELWEISS(62 kgd)
-10
-5
0
5
10
-8 -6 -4 -2 0 2 4 6 8
SIMPLE(0.42 kgd)
-10
-5
0
5
10
-8 -6 -4 -2 0 2 4 6 8
SIMPLE (3 kgd)
![Page 25: Project SIMPLE for Dark matter search](https://reader036.vdocument.in/reader036/viewer/2022062422/56813f50550346895daa0c01/html5/thumbnails/25.jpg)
Heavy project: Cf3I (ρ=2g.cm-3)for Spin-INdependent sector
![Page 26: Project SIMPLE for Dark matter search](https://reader036.vdocument.in/reader036/viewer/2022062422/56813f50550346895daa0c01/html5/thumbnails/26.jpg)
The impact of a CF3I SDD
222
)()( 4)(
:
pFASI
n
n
ASIp
p
G
gg
NZ
:NZ
0Z
N
g
g
n
p
![Page 27: Project SIMPLE for Dark matter search](https://reader036.vdocument.in/reader036/viewer/2022062422/56813f50550346895daa0c01/html5/thumbnails/27.jpg)
CF3I feasible ?
The non matching density: few preliminary calculs:
00
pff visc
0)(3
46 3
0 grt
Dr b
D
gtr b
9
)(2 02
11.13.0 smkg
The following composition gives ηexp=0.17 kg.m-1.s-1
(measured by a viscosimeter Cannon Fenske routine 1600-6400):
gelatine (1.71%)+ PVP (4.18%)+ biH2O (15.48%)+ agarose (0.46%) + glycerine (78.16%).
ρ0, η
ρb D
2
3326
10.59
)10.3.110.2)(6060(81.9)10.35(2
x
xAN
![Page 28: Project SIMPLE for Dark matter search](https://reader036.vdocument.in/reader036/viewer/2022062422/56813f50550346895daa0c01/html5/thumbnails/28.jpg)
CF3I : temperamental
High solubility under presure : S=0.5g/kg H2O/bar
High solubility at T<Tambiant : the droplets get dissolved in high quantity No stockage at T<0°C: clathrates of hydrates
Day 0 Day 1
1 night at 7ºC