Production of Unstable Nuclei for Astrophysical Studies and the new Accelerator Project at MSU

David Morrissey

Facility for Rare Isotope Beams

18 September 2014

Production of Unstable Nuclei for Astrophysical Studies and the new

Accelerator Project at MSU

Facility for Rare Isotope Beams: Program

Morrissey, Erice Sept/2o14, Slide 2

Properties of atomic nuclei • Develop a predictive model of nuclei and their interactions• Many-body quantum problem: intellectual overlap to mesoscopic

science, quantum dots, atomic clusters, etc.

Astrophysics: Nuclear Processes in the Cosmos • Origin of the elements, chemical history• Explosive environments: novae,

supernovae, X-ray bursts …• Properties of neutron stars

Tests of laws of nature• Effects of symmetry violations are

amplified in certain nuclei

Societal applications and benefits• Medicine, energy, material

sciences, national security

Nucl. Astro.: Large Number of Reactions, Much Larger Number of Nuclei …


Big Bang Nucleosynthesis

pp-chain

CNO cycle

Helium, C, O, Ne, Si burning

s-process

r-process

rp-process

νp – process

p – process

α - process

fission recycling

Cosmic ray spallation

pyconuclear fusion

+ others added all the time …

AZ

fission(α,γ)

β+ , (n,p)

β-

(p,γ)

(α,p)

(n,2n) (n,γ)

(γ,p)

Sample reaction paths

N=82

N=126

Critical region probes:Main r-process parametersProduction of actinides

Critical region probes:r-process freezeout behavior

Critical region probes:Main r-process parametersCritical region probes:

Neutrino fluence

Critical region: Disentangler-processes

Information Needed from Nuclear Physics

Morrissey, Erice Sept/2o14 , Slide 5

Speakers have already described different regions in the chart are needed to probe many aspects of astrophysical models to be compared to observations.

From:H. Schatz

FRIB reach for T1/2, masses,and β-delayed neutron emission

N=82

N=126

Critical region probes:Main r-process parametersProduction of actinides

Critical region probes:r-process freezeout behavior

Critical region probes:Main r-process parametersCritical region probes:

Neutrino fluence

Critical region: Disentangler-processes

Morrissey, Erice Sept/2o14

Information Needed from Nuclear Physics

, Slide 6

From:H. Schatz

Speakers have already described different regions in the chart are needed to probe many aspects of astrophysical models to be compared to observations.

Can We Measure All the Nuclear Reactions?


No, clearly not!

We want a path to solve the nuclear physics part of the puzzle.

Construct detailed, predictive model(s) of nuclear structure

Produce the rare isotopes that are important for modeling and measure only their properties and reactions

Rare Isotope Production Methods


• Cartoon of the isotope production process at RIB facilities:

• Inverse mechanism for ISOL production (p + heavy target)

• To produce a potential drip line nucleus like 122Zr the production cross section (from 136Xe) is estimated to be: 2x10-18 b

(2 attobarns, 2x10-46 m2 )

• Nevertheless with a 200 MeV/u 136Xe beam of 8x1013 ion/s (12 pμA, 400 kW) a few atoms per week can be made and studied

(why? >80% collection efficiency; 1 out of 1020)

In-flight Isotope Production Sensitivity


projectiletarget

(?)

Facility for Rare Isotope Beams, FRIB


Funded by DOE Office of Science, T. Glasmacher, FRIB Project Director

Key Feature is 400kW beam power

(5x1013 238U/s)

Separation of isotopes “In-flight”

Suited for all elementsand short half-lives

Fast, stopped, and reaccelerated radioactive beams

Layout of FRIB Acceleratorand NSCL Experimental Areas

Target

Folding Segment 2

Linac Segment 3

Linac Segment 1Beam Delivery System

Front End

Reaccelerator

Linac Segment 2

Fast Beam Area Gas Catching Thermalized Beam Area

Reaccelerated Beam Areas

Fragment Separator

Folding Segment 1


New AcceleratorComplex

FRIB Driver: New Linear Accelerator


FRIB Production: New Hot Cell & Separator



Three Experimental Energy Regimes

Radioactive Ion Beams are needed/available in three energy domains:

Fast ~100 MeV/u

Thermalized 60 keV/q

Reaccelerated 0.3 up to x MeV/u

Fast

Reaccelerated

Thermalized

Fast (planned)

Reaccelerated(equip. planned)

Note: darker-shaded areas in use at present NSCL.

Separation of Fast Beams


Example of Fragment Selection Technique: 86Kr50 78Ni50 DZ= -8

fragment yield after target fragment yield reaching wedge fragment yield at focal plane

Secondary beams are produced at ~100 MeV/u and often “cocktail” beams thus, event-by-event ID of beam particles is usually necessary

Detailed Nuclear Structure work has been successful with spectrometers

Detailed Decay Studies have been successful by tagging implanted nuclei

Not suited to direct reactions, precision work due to poor emittance both longitudinal and transverse

Where is the Neutron Drip-line in Theory


Z=13

Yellow Squares: already observed w/ Fast BeamsBlack Line: Finite-Range Liquid-Drop Moeller, et al. ADNDT 59 (1995) 185Green Lines: Hartree-Foch-Bogoliubov Goriely, et al. Nucl.Phys. A750 (2oo5)425 http://www-astro.ulb.ac.be/Html/hfb14.html

Z=13

e.g., Shell Model by B.A. Brown (MSU)

Z=13

Z=13

Ratio of Measured Cross Section to Systematics (EPAX3)82Se (139 MeV/u) + 9Be target

O. Tarasov, et al. PRC 87 (2013) 054612Black Sq. – stableColored Sq. – measured , s d /s dp

82Se


Evolution of Shell Structure Observed with Fast Beams in Neutron-rich Nuclei


cf. recent review by R. Kanungo, Phys. Scr. 2013 014002

Thermalized Beams for Nuclear Science


Thermalized target fragments have a long and rich history, e.g., ISOLDE, TRIUMF, IGISOL, etc-SOL

Thermalized projectile fragments are now available, selection of individual isotopes from proj. fragment “cocktail” is now possible.

Precise Mass Measurements of very exotic nuclei

Detailed Decay Studies are possible with pure sources (no Particle ID tagging and extraneous

backgrounds)

Laser spectroscopy of very exotic nuclei for nuclear moments and other fundamental properties

Mass Measurements in rp-process region


-6 -4 -2 0 2 4 6

36

37

38

39

40

41

42

mea

n tim

e of

flig

ht [s

]

RF

[Hz] -2121268-30 -20 -10 0 10 20 30

30

31

32

33

34

35

36

37

38

me

an

tim

e o

f fli

gh

t [s

]

c - 2186663 Hz

- 4 - 2 0 2 42 2 . 0

2 2 . 5

2 3 . 0

2 3 . 5

2 4 . 0

2 4 . 5

2 5 . 0

me

an

tim

e o

f flig

ht [

s]

R F

- 2 2 1 9 1 8 0 [ H z ]

29 30 31 32 33 34 35 36 37 38 39 40 41 ZN

30Zn

6465

6766

37

36

35

34

33

32

31

Rb

Kr

Br

Se

As

Ge

Ga

68 70

7170

68

69

N=Z

-20 -10 0 10 2040.0

40.5

41.0

41.5

42.0

42.5

me

an

tim

e o

f flig

ht /

s

RF

-2060450 / Hz

70mBr T1/2=2.2s66As T1/2=95ms

rp-process waiting point

68Se T1/2=35s

dm= 500 eV Proton drip-line nucleusone of the shortest-lived nuclei studied in a Penning trap

64GeH T1/2=63.7s

Rp-process waiting point

66As measured with ≈ 10 ions/hr

Schury, et al. PR C75 (2oo7) 055801 Savory, et al. PRL 102 (2oo9) 132501

FRIB Reach for r-Process Measurements

Known mass

Mass measurements

Drip line to be established ?

H. Schatz


Ca

Zr

Zn

Total Absorption Spectroscopypure sources of Projectile Fragments


Silicon Trigger detector

Beam76Ga @ 45 keV

~ 500 pps“No beam

contaminants observed.”

Detector15” x 15” NaI(Tl)

A.Spyrou, et al., PRL (2014) submitted

Reaccelerated Beam of Nuclear Science

Reacceleration of target fragments is beginning, e.g., HIE-ISOLDE, TRIUMF-ISAC, etc.

Reacceleration of projectile fragments is also starting with thermalized proj. fragments

ReA3 at MSU

1+ ions

n+ ions

stable Rb1+ ions from N4 (Mar/13) 76Ga from A1900/N4 (meas. Decay, Apr/13) ANASEN (active target device) 37K Jul/13

108-9

107-8

106-7

105-6

104-5

102-4

109-1010>10

Highest intensities: Allow reaction rates up to ~Ti could be directly measured

Most reaction rates up to ~Sr can be directly measured

Predicted Reacceleratedbeams rates

direct (p,g)

direct (p,a) or (a,p)transfer

(p,p), some transfer

rp-process

FRIB Reach for Novae and X-ray burst reaction rate studies

From H. Schatz


Specialized equipment (SECAR & gas Target) allow direct rxn studies

FRIB is Becoming Real: Ground Breaking March 17, 2014


FRIB construction site 17 March 2014 – www.frib.msu.edu

http://www.frib.msu.edu/


FRIB is Becoming Real: Civil Construction is a Few Weeks Ahead of Baseline Schedule

FRIB construction site: 17 Sept 2014 – webcam: www.frib.msu.edu



Project started in June 2009• Michigan State University selected to design and establish FRIB • Cooperative Agreement signed by Dept. of Energy (DOE) and MSU in June 2009

Conceptual design completed; Critical Decision 1 (CD-1) approved in Sept. 2010

Preliminary technical design, final civil design, and R&D complete

CD-2/3A approved in August 2013• Project baseline and start of civil construction after additional notice from the DOE Office of Sci.

Civil Construction began March 3, 2014

Final technical design begins with goal to be completed in 2014

CD-3B review in June 2014, approved in Aug, 2014 formal start of construction

Managing to early completion in 2020• CD-4 (formal project completion) is 2022

Cost to DOE - $635.5 million• Total project cost of $730M includes $94.5M cost share from MSU• Value of MSU contributions (building/equipment) above cost-share exceeds $265M

FRIB Project: Milestones and Budget

, Slide 30Morrissey, Erice Sept/2o14

Thank you for your attention !


It may have been a long road but we’re almost there !

The Nuclear Landscape

256 “Stable” – no decay observed3184 Total in the NNDC Database


Nuclear Balance across Chart of Nuclides


Upper end limited by electrostatic explosion

Less than 300 isotopes(stable or long-lived)

“known” nuclei

“possible” nuclei

neutron drip-lineproton drip-line

Develop a comprehensive model of atomic nuclei – How do we understand the structure and stability of atomic nuclei from first principles?

Understand the origin of elements and model extreme astrophysics environments

Use of atomic nuclei to test fundamental symmetries and search for new particles (e.g. in a search for CP violation)

Search for new applications of isotopes and solution to societal problems

Challenges to Nuclear Science

Why do atoms exist?

Where do atoms come from?

What are atoms made of?

What are they good for?

Studies at the extremes of neutron and proton number are necessary to answer these questions.


Shifting Energy Levels in Nuclei


Dobaczewski, et al. PRL 72 (94) 981For A=100 Drip Lines: Zn – Sn

h11/2

very diffusesurfaceneutron drip line

g9/2

g7/2

d5/2

d3/2s1/2

h11/2

h9/2

f5/2

f7/2

p3/2

p1/2

82

1g

V=5

V=4

2d3s

1h

2f3p

g9/2

g7/2

d5/2

d3/2

s1/2

p3/2

h9/2

p1/2

i13/

2

f5/2

f7/2

50

126

harmonicoscillator

l 2no spinorbit

near thevalley ofb-stability

40

70

112

Prediction of the limits of the nuclear landscape

J. Erler et al., Nature 486, 509 (2012); A.V. Afanasjev et al. PLB 726, 680

Total number of 6900(500) possible for atomic numbers less than 120.


The Predicted Limits for Zr IsotopesMod. Phys. Lett. A29 (2014) 1430010


Comparison of Calculated and Measured Binding Energies with NN models

Greens Function Monte Carlo techniques allow up to mass number 12 to be calculated

Blue 2-body forces V18

S. Pieper B.Wiringa J Carlson, et al.

NN potentialNN + NNN potential


New information from exotic isotopes

• Neutron rich nuclei were key in determining the isospin dependence of 3-body forces and the development of IL-2R from UIX

• New data on exotic nuclei continues to lead to refinements in the interactions

NN + improved NNN potential

Properties of exotic isotopes are essential in determining NN and NNN potentials

S. Pieper B.Wiringa, et al.


E. Olsen et al, PRL 111, 139903 (2013)

sequ

entia

lsi

mul

tane

ous

NSCL

48Ni 2p

GSI - FRS

31Ar b3p

ISOLDE

6He + a d

The landscape of two-proton radioactivity

W. Nazarewicz

http://www.fuw.edu.pl/~pfutzner/Research/OTPC/OTPC.html


Stars are mostly made of hydrogen and helium, but each has a unique pattern of other elements

The abundance of elements tell us about the history of events prior to the formation of our sun

The plot at the right shows the composition in the visible surface layer of the Sun (photosphere)

How were these elements created prior to the formation of the Sun?

One of the Challenges – Origin Elemental Abundances in our Solar System

Hydrogen

XLogdex 12

Asplund, M., Grevesse, N., Sauval, A.J., Scott, P.: Annu. Rev. Astron.Astrophys. 47, 481 (2009)


Sample data 82Se (139 MeV/u) + Be, WO. Tarasov et al. PRC 87 (2013) 054612


The Quest for r-process Nuclear Physics

FRIB

N=50

N=82N=126

ANL Trap @ CARIBU

JyvaskylaTrap

TRIUMF Trap

CERN/ISOLDETrap

NSCLTOF

GSIESR Ring

ORNL (d,p)

GSI/Mainz T1/2 Pn

ORNL T1/2 Pn

RIKEN T1/2

NSCL T1/2 Pn

CERN/ISOLDE T1/2 Pn

9Be(g,n)HIgS

+ Neutrino Physics+ Nuclear Matter EOS+ Fission

Brett et al. 2012 Sensitivity to MassesZ

N

FRIB reach

CARIBU reach

FAIR, RIBF, SPIRAL2, EURISOL

H SchatzMorrissey, Erice Sept/2o14 43

Evidence for the First Stars in the UniverseSDSS J001820.5–093939.2 SUBARU Observations Aoki et al., SCIENCE 345 (2014)

Type II

Type Ia

PISM

Unique features

Model comparisons


Importance of 3N forces

Big Bang Nucleosynthesis: Calculate all key reactionsNeutron star masses

Half-life of 14C (Maris, Navratil et al. PRL), structure of calcium isotopes (Wienholtz et al. Nature), etc.

S. Gandolfi et al., PRC85, 032801 (2012)

Talk on Monday

Nazarewicz et al.


Stellar Hydrogen Explosions:Common (100/day) and Not Understood

Open questions• Neutron star size• Short burst intervals• Multiple peaked bursts• Nature of superbursts• Ejected mass

(Nucleosynthesis)• Observable gamma

emitters• Why such a variety • Path to Ia supernovae

www4.nau.edu

H SchatzMorrissey, Erice Sept/2o14, Slide 46

http://www4.nau.edu/meteorite/Meteorite/Book-GlossaryX.html

Rare Isotope Crusts of Accreting Neutron Stars

Nuclear reactions in the crust set thermal properties (e.g. cooling)

Can be directly observed in transients Directly affects superburst ignition

Understanding of crust reactions offers possibility to constrain neutron star properties (core composition, neutrino emission…)

Cackett et al. 2006 (Chandra, XMM-Newton)

KS 1731-260(Chandra)

H. SchatzMorrissey, Erice Sept/2o14, Slide 47

Beta-delayed Particle Emission


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Mass Number, A

Mas

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eV)

Nitrogen Q-beta

Oxygen Sn

Carbon Sp

Q

pS

nS

Use proton induced fission of 238U with 400 kW 600 MeV protons from FRIB

ISOL Production of 5×108/s 80Zn

Acceleration to 160 MeV/u with the K1200 Cyclotron (200 MeV/u maximum energy)

Production of nuclei along the drip line up to 70Ca

Future Prospects for Drip Line Study (EURISOL or upgraded FRIB with ISOL)


Documents

Production of Unstable Nuclei for Astrophysical Studies and the new Accelerator Project at MSU