PHYSICS WITH MINOSAT THE RIBF
A. Obertelli
CEA Saclay, RIKEN Nishina Center (JSPS fellow)
Conference on Advances in Radioactive Isotopes Science ARIS 2014

MINOS : Magic Numbers Off Stability
Project started in November 2010

Cooling system

Time Projection Chamber(Micromegas amplification)

Liquid hydrogen target

09/06/2014

A. Obertelli et al., Eur. Phys. Jour. A 50, 8 (2014)
http://minos.cea.fr

Hosted in the Spin-Isospin Laboratory at the RIKEN Nishina Center (T. Uesaka’ s lab)

MINOS : Magic Numbers Off Stability

In-beam knockout experiments
Position sensitive detector: X,Y
Drift time: Z beam-axis direction
protone-Vertex resolution : < 5 mm FWHM
Detection efficiency > 85%
09/06/2014

cathode+6000V

protonA. Obertelli et al., Eur. Phys. Jour. A 50, 8 (2014)
http://minos.cea.fr

Hosted in the Spin-Isospin Laboratory at the RIKEN Nishina Center (T. Uesaka’ s lab)

Improving luminosity, resolution and sensitivity
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Higher luminosity (150 cm H2 = 1 g.cm-2 = 4. 1023 cm-2)
Improved energy resolution : cancelation of the target contribution
Quasifree (p,2p) or (p,pn): “clean” probeSee talk by A. Bonaccorso
Access to intrinsic momentum distributions despite thick target (to be proved)
Minimized background (pure H2 target, less bremsstrahlung/neutrons)

Doppler correction 𝐸 = 𝐸𝛾

DALI2 g array

Geant4 simulation(1 − 𝛽 cos 𝜃)
1 − 𝛽253K(p,2p)52Ar @ 250 MeV/nucleon

MINOS : hydrogen target
Liquid H2 Target
150 mm Mylar cell
20 – 200 mm longcondensor

2,1 m(Cryostat)

AO and T. Uesaka, EPJA 47, 105 (2011)
C. Louchart et al., NIM A 736, 81 (2014)

MINOS: time projection chamberFeatures
High granularity detector (TPC)• 30 cm long / 15 cm diameter> 4000 pads, size 4 mm2• very low material budget• Ar(85%)CF4(12%)iso(3%) gas:drift velocity: 4.5 cm/msdispersion: 200 mm  cm• AGET: digital, 512 time bin, 100 MHz
MicroMegas (IRFU)
individual discriminator / channel
typical dead time of 150 ms / event

New Electronics and SoftTPC
> 85% efficiency< 5 mm FWHM resolution
09/06/2014
First use of AGET
chip in a physics experiment (GET project: CEA, IN2P3, NSCL collaboration)

In-beam validation
HIMAC in October 2013

He + CH2 @ 200 MeV/nucleon

Target 1

Target 2

Experiment: 5 mm FWHM
Simulation: 6 mm FWHM

09/06/2014

MINOS tracking and TPC performances: poster by C. Santamaria PS2-C022

Physics program with MINOS

1) Origin of di-neutron correlations in halo nuclei2) Three-body forces and continuum : binding energy of Oxygen isotopes
3) Shell evolution and search for 21+ states in neutron rich nuclei (SEASTAR)

Origin of di-neutron correlations in Halo nuclei
Spokespersons: Y. Kubota (CNS, RIKEN) and A. Corsi (CEA)Study of 6He, 11Li, 14Be and 17,19B
Ex. 11Li(p,pn)10Li  9Li + n

Kc-nn

I. Tanihata et al., PRL 100, 192502 (2008)
G. Potel et al., PRL 105, 172502 (2010)
11Li(p,t)9Li at 3 A MeV

kn-n

A unique program to understand Neutron Halos:• multipole decomposition from (p,pn)• minimized Final State Interactions• core excitations (g detection)

MINOS and RIBF beams high luminosity (100 gain in statistics) required:• Exclusive measurement: p,2n,gamma, heavy-ion (4 and 5-fold coincidence)• Large momentum transfer for low FSI: low cross section

Final State Interactions: case of 6He

Ground-state (non-observable)

Asymptotic cross-section (observable)

Dineutron-like

Dineutron-likeCigarlike

Cigarlike

6He

kα-n

Dineutronlike

5He

kα-n

Dineutron-like need for differential cross sections
Preliminary work by Y. Kikuchi (RIKEN) and K. Ogata (RCNP)Spectroscopy of unbound Oxygen isotopes
H. Sakurai et al., PLB 448, 180 (1999)

Benchmark for three-nucleon force studies
Talk by A. Schwenk

dripline
24O

28O

T. Otsuka et al., PRL 105, 032501 (2010)
G. Hagen et al., PRC 80, 021306(R) (2009)
A. Cipollone et al., PRL 111, 062501 (2013)
H. Hergert et al., PRL 110, 242501 (2013)

Spectroscopy of unbound Oxygen isotopes
Spokesperson: Y. Kondo, Tokyo Institute of Technology
Invariant mass
Talk by Y. Kondo

e4n = 0.8%
for Edecay = 4 MeV
with 3 detection layers

4n29F(p,2p)28O  24O + 4n

Expected intensity: 13 pps
NEBULA (2 layers)
24OMINOS thick H2 target: high luminosity!
Vertex tracking: improve decay energy resolution.

NeuLAND (1 layer)from 2015

Shell Evolution and Search for Two-plus Energies
At the RIBF (SEASTAR) – a RIKEN Physics program
Spokespersons: P. Doornenbal (RIKEN), A. Obertelli (CEA, RIKEN)

80
79Cu Zn
66Cr

78Ni

70,72FePSP framework promoted by H. Sakurai (RIKEN, Univ. of Tokyo)
You are welcome to the SEASTAR collaboration!
http://www.nishina.riken.jp/collaboration/SUNFLOWER/experiment/seastar/index.html

First SEASTAR campaign, may 2014
View of (some) collaborators at secondary target position
SUNFLOWER : in-beam gamma at the RIBF
See talks by N. Aoi, A. Corsi, D. Steppenbeck

BigRIPS spectrometer
09/06/2014
See talk by N. Fukuda

DALI2-MINOS setup

DALI2MINOS

09/06/2014

15

69Co(p,2p)68Fe @ 200 MeV/u: proof of principleb, vertex from MINOS

Doppler corr. energy (keV)

fixed b, fixed vertex

Beam axis Z (mm)Beam axis Z (mm)Successful SEASTAR campaign.
physics results for 66Cr, 72Fe, 78Ni and others available soon!

AGATA - GRETINA at the RIBF:
a possible exciting physics program with MINOS
Ultimate use of new HPGe g arrays with MINOS for in-beam g spectroscopy:(++) High resolution (<15 keV at 1 MeV), (++) High luminosity,(++) High efficiency and peak over total ratio

Simulation at 300 MeV/uWith 10 AGATA TC

GRETINA with fast beams
Talk by A. GadeAGATA
Talk by D. Mengoni

Summary• MINOS is a new detector to be used at the RIKEN RIBF
Thick liquid hydrogen target and vertex tracker. First of its kind.
• Unique advantages:
1) High luminosity2) Improved resolution3) Clean reaction probe for knockout
An exciting physics program at the RIBF has started:• Origin of di-neutron correlations in halo nuclei• Three-body forces and continuum : binding energy of Oxygen isotopes• Shell evolution and search for 2+ states in neutron rich nuclei (SEASTAR)-- First spectroscopy of 66Cr, 72Fe and 78Ni recently measured –http://minos.cea.fr

Collaborations
MINOS development and local teams
S. Anvar, L. Audirac, G. Authelet, H. Baba, B. Bruyneel, D. Calvet, F. Chateau, A. Corsi, A. Delbart, P. Doornenbal, J.-M. Gheller, A. Giganon, T. Isobe, Y.
Kubota, C. Lahonde-Hamdoun, D. Leboeuf, D. Loiseau, M. Matsushita, A. Mohamed, J.-Ph. Mols, T. Motobayashi, M. Nishimura, S. Ota, H. Otsu, C. Péron, A.
Peyaud, E.C. Pollacco, G. Prono, J.-Y. Rousse, H. Sakurai, C. Santamaria, M. Sasano, R. Taniuchi, S. Takeuchi, T. Uesaka, Y. Yanagisawa, K. Yoneda

Physics collaborations
Di-neutron correlations H. Baba, D. Beaumel, P. Doornenbal, M. Dozono, T. Isobe, Y. Kikuchi, T. Motobayashi, H. Otsu, M. Sasano, H. Sato, Y. Shimizu,S. Takeuchi, T. Uesaka, K. Yoneda, J. Zenihiro (RIKEN Nishina Center), A. Corsi, A. Gillibert, A. Obertelli, E. C. Pollacco, C. Santamaria (CEA Saclay), S.
Kawase, M. Kobayashi, M. Matsushita, S. Ota, M. Takaki, T. L. Tang, H. Tokieda, K. Yako (CNS), K. Kisamori, Y. Kubota, C. S. Lee (CNS and RIKEN
Nishina Center), K. Kobayashi (Rikkyo University), T. Kobayashi (Tohoku University), Y. Kondo, T. Nakamura, Y. Togano (Tokyo Institute of Technology), K.
Ogata (RCNP)
Oxygen isotopes Y. Kondo, T. Nakamura, Y. Togano, M. Shikata, J. Tsubota (Tokyo Tech), H. Baba, H. Sato, K. Yoneda, H. Otsu, T. Isobe, M. Sasano, Y.
Shimizu, T. Uesaka (RIKEN Nishina Center), T. Kobayashi (Tohoku University), F. Château, D. Calvet, A. Gillibert, J.-M. Gheller, V. Lapoux, A. Peyaud, A.
Obertelli, A. Corsi, E.C. Pollacco, C. Santamaria (CEA Saclay), T. Aumann, H. Scheit (TU Darmstadt), N. Orr, J. Gibelin, F.M. Marques, S. Leblond, N.L.
Achouri, F. Delaunay (LPC Caen), Y. Satou, S. Kim, J. Hwang (Seoul National University), T. Murakami, N. Nakatsuka (Kyoto University), C.R. Hoffman(Argonne National Laboratory), A. Navin, M. Rejmund, A. Lemasson (GANIL), S. Stephenson (Gettysburg college), H. Simmon (GSI)
SEASTAR N. Alamanos, G. de Angelis, N. Aoi, H. Baba, C. Barbieri, C. Bertulani, A. Corsi, F. Delaunay, Z. Dombradi, P. Doornenbal, T. Duguet, S.
Franchoo, J. Gibelin, A. Gillibert, S. Go, M. Gorska, A. Gottardo, S. Grévy, J.D. Holt, E. Ideguchi, T. Isobe, A. Jungclaus, N. Kobayashi, T. Kobayashi, Y.
Kondo, W. Korten, Y. Kubota, I. Kuti, V. Lapoux, S. Leblond, J. Lee, S. Lenzi, H. Liu, G. Lorusso, C. Louchart, R. Lozeva, F.M. Marques, I. Matea, K. Matsui,Y. Matsuda, M. Matsushita, J. Menendez, D. Mengoni, S. Michimasa, T. Miyazaki, S. Momiyama, P. Morfouace, T. Motobayashi, T. nakamura, D. Napoli, F.
Naqvi, M. Niikura, A. Obertelli, N. Orr, S. Ota, H. Otsu, T. Otsuka, N. Pietralla, Z. Podolyak, E.C. Pollacco, G. Potel, G. Randisi, F. Recchia, E. Sahin, H.
Sakurai, C. Santamaria, M. Sasano, A. Schwenk, Y. Shiga, Y. Shimuzu, S. Shimoura, J. Simonis, P.A. Soderstrom, S. Sohler, V. Soma, I. Stefan, D.
Steppenbeck, T. Sumikama, H. Suzuki, M. Tanaka, R. Taniuchi, K.N. Tuan, T. Uesaka, J. Valiente Dobon, Zs. Vajta, D. Verney, H. Wang, V. Werner, Zh. Xu,R. Yokoyama, K. Yoneda