A Recoil Separator for ALNA-Phase2
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This project is funded by the NSF This project is funded by the NSF through grant PHY0216783, and the through grant PHY0216783, and the Universities of JINA. Universities of JINA. The Joint Institute for Nuclear Astrophysics Henderson DUSEL Capstone Workshop A Recoil Separator for ALNA-Phase2 A Recoil Separator for ALNA-Phase2 Manoël Couder University of Notre Dame Joint Institute for Nuclear Astrophysics
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Mano ë l Couder University of Notre Dame Joint Institute for Nuclear Astrophysics. A Recoil Separator for ALNA-Phase2. Charged particles cross section measurements at low energy. Effort to extract the signal at low energy are needed because cross section drops exponentially - PowerPoint PPT Presentation
Transcript of A Recoil Separator for ALNA-Phase2
This project is funded by the NSF through This project is funded by the NSF through grant PHY0216783, and the Universities of grant PHY0216783, and the Universities of
JINA.JINA.
The Joint Institute for Nuclear Astrophysics
Henderson DUSEL Capstone Workshop
A Recoil Separator for ALNA-A Recoil Separator for ALNA-Phase2Phase2
A Recoil Separator for ALNA-A Recoil Separator for ALNA-Phase2Phase2Manoël Couder
University of Notre DameJoint Institute for Nuclear Astrophysics
This project is funded by the NSF through grant PHY0216783, and the Universities of
JINA.
The Joint Institute for Nuclear Astrophysics
Henderson DUSEL Capstone Workshop
Charged particles cross section measurements at low energy
Effort to extract the signal at low energy are needed because cross section drops exponentially
Increase the number of interactions•Beam intensity increased•Gas target are more and more elaborated
Improved detection techniques •Gamma detector: 4 segmented•Active shielding
Tracking Arrays based onPosition Sensitive Ge Detectors
Large Gamma Arrays based onCompton Suppressed Spectrometers
40 — 20 % ( M=1 — M=30)
10 — 5 % ( M=1 — M=30)
GAMMASPHEREEUROBALL GRETAAGATA
Slide from: J. Simpson, “The AGATA project”, NPDC19, 2005
This project is funded by the NSF through grant PHY0216783, and the Universities of
JINA.
The Joint Institute for Nuclear Astrophysics
Henderson DUSEL Capstone Workshop
Charge particles Cross section measurements at low energy – Status
Effort to extract the signal at low energy (fight against background) are needed because cross section drops exponentially:
Increase the number of interactions•Beam intensity increased•Gas target are more and more elaborated
Try to extract more by improving detection techniques •Gamma detector: 4 segmented•Active shielding
Underground laboratory
This project is funded by the NSF through grant PHY0216783, and the Universities of
JINA.
The Joint Institute for Nuclear Astrophysics
Henderson DUSEL Capstone Workshop
p, 4He beam
Target
raysDirect kinematics: Light ion beam on heavy target
Find additional tags to improve detection for (p,) and (,)
No additional tag possible only fight to increase signal to noise ratio.
rays
p, 4He target
Inverse kinematics: “Heavy ion” beam on light target
HI beamHI beam
Reaction products1017 @100A for 1 recoil/10 min
Require rejection of the beam-> RMSExisting device: DRAGON @ TriumfERNA @ Bochum…
This project is funded by the NSF through grant PHY0216783, and the Universities of
JINA.
The Joint Institute for Nuclear Astrophysics
Henderson DUSEL Capstone Workshop
DRAGON @ Triumf
DRAGONISACRadioactive beam induce reaction -> Inverse
kinematics is the only solution.
Example with stable beam induce reaction21Ne(p,g)22Na
Spectrum and picture from S. Engels Thesis, http://dragon.triumf.ca/docs/sabine_thesis.pdf
Recoil energy spectra in singles and coincidence mode for 21Ne(p,)22Na atEcm = 258.6 keV
Gamma energy spectrum in singles and coincidence mode
Residual beam
This project is funded by the NSF through grant PHY0216783, and the Universities of
JINA.
The Joint Institute for Nuclear Astrophysics
Henderson DUSEL Capstone Workshop
12C(,)16O @ ERNA - Bochum
@ Ecm = 3.2 MeV Spectrum from D. Schürmann, Santa Tecla D. Schürmann, Santa Tecla 20052005
BaF2 detector
•Signal•Cosmic and room background•Beam induced background
Spectrum from F. Strieder, Tuckson 2003F. Strieder, Tuckson 2003
This project is funded by the NSF through grant PHY0216783, and the Universities of
JINA.
The Joint Institute for Nuclear Astrophysics
Henderson DUSEL Capstone Workshop
Why a RMS underground ?
The dramatic cosmic background reduction leaves the environmental and beam induce background. The number of bad – HI coincidence decrease !!
The Notre Dame Recoil Mass separator
Design of a RMS for (,) reaction studies at low energy for beam with 16<A<40. Large acceptance <40 mrad E/E<7.4% Required for reaction of interest: 22Ne(,)26Mg, 18O(,)22Ne
Mass separation achieved with a Wien filter New design of the electrodes
First beam expected late 2007 Good prototype for underground laboratory
High intensity AC accelerator is required for beam up to A=40 Source and accelerator development @ LBNL
This project is funded by the NSF through grant PHY0216783, and the Universities of
JINA.
The Joint Institute for Nuclear Astrophysics
Henderson DUSEL Capstone Workshop
The Notre Dame RMS
Charge selection
Jet gas target + post-stripper detectors
Wien Filter – Mass separation
Detection system
8cmReco
ilBea
m
Recoil+Beamq selected
Beamq+2 q+1
This project is funded by the NSF through grant PHY0216783, and the Universities of
JINA.
The Joint Institute for Nuclear Astrophysics
Henderson DUSEL Capstone Workshop
G.P.A. Berg1, M. Couder1, J. Görres1, J. Hinnefeld2,
L.O. Lamm1, P.J. Leblanc1, E. Stech1, M. Wiescher1
1 University of Notre Dame.2 Indiana University, South Bend.
Summary: RMS must accept ALL the recoils
Large angular and energy acceptance
Low event rate ~1/few hours Rejection important >1020 beam ions
Low energy No ID of the heavy ion, no additional discrimination ray – HI coincidence is crucial to make a TRUE EVENT ID
