Download Manoel Couder

I NSTITUTE FOR S TRUCTURE AND N UCLEAR A STROPHYSICS
N UCLEAR S CIENCE LABORATORY
CASPAR
An underground Accelerator
Laboratory for Nuclear
Astrophysics
Manoel Couder
University of Notre Dame
I NSTITUTE FOR S TRUCTURE AND N UCLEAR A STROPHYSICS
N UCLEAR S CIENCE LABORATORY
• Neutron sources for the s-process
• CASPAR
– Facility
– Collaboration
– Timeline
ARUNA 2014
I NSTITUTE FOR S TRUCTURE AND N UCLEAR A STROPHYSICS
N UCLEAR S CIENCE LABORATORY
s-process nucleosynthesis
Two components were identified and connected to stellar sites:
Main s-process ~90<A<210
Weak s-process A<~90
TP-AGB stars 1-3 M⊙
shell H-burning
0.9·108 K
kT=8 keV
107-108 cm-3
13C(a,n)16O
massive stars > 8 M⊙
core He-burning
shell C-burning
3-3.5·108 K
~1·109 K
kT=25 keV
kT=90 keV
106 cm-3
1011-1012 cm-3
22Ne(a,n)25Mg
He-flash
3-3.5·108 K
kT=25 keV
1010-1011 cm-3
22Ne(a,n)25Mg
ARUNA 2014
I NSTITUTE FOR S TRUCTURE AND N UCLEAR A STROPHYSICS
N UCLEAR S CIENCE LABORATORY
22Ne(a,n)25Mg
Status of direct measurements
22Ne(α,n)25Mg
22Ne(α,n)25Mg
ARUNA 2014
I NSTITUTE FOR S TRUCTURE AND N UCLEAR A STROPHYSICS
N UCLEAR S CIENCE LABORATORY
26Mg(g,
g)
HIgS
26Mg(g,n)
Longland et al. 2009
5)
4)
3)
2)
1)
ER = 11153.5(1) keV, Jπ = 1+ cannot
contribute to the n-channel
ARUNA 2014
I NSTITUTE FOR S TRUCTURE AND N UCLEAR A STROPHYSICS
N UCLEAR S CIENCE LABORATORY
(a,a’) and (6Li,d) at RCNP Osaka
22Ne(6Li,d)
26Mg(α,α’)
ARUNA 2014
I NSTITUTE FOR S TRUCTURE AND N UCLEAR A STROPHYSICS
N UCLEAR S CIENCE LABORATORY
Status
13C(α,n)
Contribution from below threshold
at -3 keV has been evaluated with
Trojan Horse Method.
M. La Cognata et al.
Since the present technical possibilities appear
to be exhausted, a reduction of the remaining
uncertainty can probably only be achieved in an
underground laboratory, where the cosmic-ray
induced γ background can be avoided.
M. Heil et al., Phys. Rev. C 78, 025803 (2008)
ARUNA 2014
I NSTITUTE FOR S TRUCTURE AND N UCLEAR A STROPHYSICS
N UCLEAR S CIENCE LABORATORY
CASPAR
Compact Accelerator System to Perform Astrophysics Research
At the Sanford Underground Research Facility (USA/SD)
ARUNA 2014
I NSTITUTE FOR S TRUCTURE AND N UCLEAR A STROPHYSICS
N UCLEAR S CIENCE LABORATORY
CASPAR
Proton and Helium beam from a 200 kV to 1MV electrostatic accelerator
Bombard an extended 22Ne gas target surrounded
by 3He neutron detector
Complementary to LUNA
research program
Different energy range
Helium beam allowed
ARUNA 2014
I NSTITUTE FOR S TRUCTURE AND N UCLEAR A STROPHYSICS
N UCLEAR S CIENCE LABORATORY
CASPAR
10-3 to 10-4 neutron
background of surface
Low internal background 3He tube
S. Falahat et al., NIMA 700 (2013) 53
ARUNA 2014
I NSTITUTE FOR S TRUCTURE AND N UCLEAR A STROPHYSICS
N UCLEAR S CIENCE LABORATORY
CASPAR
Collaboration between:
University of Notre Dame
South Dakota School of Mines and Technology
Colorado School of Mines
JN 1MV accelerator (H and He beams)
Refurbishment and control system
Neutron detector
Technical support
Local support
In charge of operation
ARUNA 2014
Aggressive time line:
Installation completed by mid-2015
Will be operational before any new
underground accelerator program in
the world
Gas target for isotopically enriched gas
Construct the laboratory
Partially fund the
installation of CASPAR
I NSTITUTE FOR S TRUCTURE AND N UCLEAR A STROPHYSICS
N UCLEAR S CIENCE LABORATORY
CASPAR Science goals
Neutron Sources and Neutron Poisons
13C(α,n)16O, 22Ne(α,n)25Mg, 22Ne(α,γ)26Mg, 17O(α,n)20Ne, 17O(α,γ)21Ne
Total program: (5-8 years)
Preliminary measurement at Notre Dame and elsewhere
to optimize underground studies
Other science goals
• Other nuclear astrophysics questions
• Reaction of interest for fusion energy and plasma physics
ARUNA 2014
I NSTITUTE FOR S TRUCTURE AND N UCLEAR A STROPHYSICS
N UCLEAR S CIENCE LABORATORY
Collaborations
• CASPAR
– SDSM&T: D. Wells + ???
– CSM: U. Greife
– UND: H.-S. Jung , D. Robertson, K. Setoodehnia, M. Wiescher
– Friends @ UNC A. Champagne
ARUNA 2014