[email protected]@Euroschool2013.JINR.RU Preparing the technical part of...
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Transcript of [email protected]@Euroschool2013.JINR.RU Preparing the technical part of...
Euroschool on Exotic Beams: 20th anniversary !
2 paying back tuition loans after 20 years…
Production of Exotic Beams @ Euroschools
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“In-Flight Separation of Projectile Fragments” by David J. Morrissey and Brad M. Sherrill Lect. Notes Phys. 651,
113–135 (2004)
“Isotope Separation On Line and Post Acceleration” by Piet Van Duppen Lect. Notes Phys. 700,
37–77 (2006)
“Production and acceleration of rare-isotope beams” by Giovanni Bisoffi Euroschool 2012,
Athens, Greece
ISOL & In-flight methods, ion sources, accelerators et al.
http://iks32.fys.kuleuven.be/files/euroschool/2012_Giovanni_Bisoffi.zip
Preparing the technical part of experimental proposal
4
After discussions with some outstanding theorists,
professors, who have brilliant ideas for physical
motivation of an experiment,
it seems to me, that the good direction of this year
lectures is to create a manual how to prepare a technical
part of the proposal for the in-flight production and
selection experiment.
Step by step from the beginning with the use of examples
prepared with the LISE++ code.
What is approach to the
“Production of exotic beams” lectures at 2013 ?
Production of …. ??
5
• Production of
Exotic Beams
• Production of Radioactive Ion Beams
• Production and acceleration of rare-isotope beams (Euroschool 2012)
• Stable 12C is one of most exotic nuclei ?!
triple α process
• Do not speak in public a word
“radioactivity” that scares our
neighbors. They already have
problems with the radon in their
basements according to EPA
(Environmental Protection Agency).
We are not guilty for that!
• That is really rare for
the In-flight method,
mostly is
unachievable for the
ISOL method
• Stable 40Ca : $.32/oz,
whereas
stable 48Ca : $7M/oz
48Ca is exotic or rare?
Production of Fast Rare Ion Beams
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Fast Rare Ion Beams
Please, do not mix with the Facility for Rare Isotope Beams!
Important step forward for FRIB
A note from Thomas Glasmacher
On August 1, 2013, the Department of Energy’s Office of Science (DOE-SC) approved
Critical Decision-2 (CD-2), Approve Performance Baseline, and Critical Decision-3a (CD-
3a), Approve Start of Civil Construction and Long Lead Procurements, for the Facility for
Rare Isotope Beams (FRIB) project. CD-2 formally establishes the cost and schedule for
the FRIB project. The Total Project Cost for FRIB is $730M, of which $635.5M will be provided by DOE and $94.5M will be shared by the community. FRIB will be completed by
June 2022 and the project is managing to an early completion in December 2020.
So…
Why LISE++ ? What is it ?
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“Step by step from the beginning with the use of examples prepared with the LISE++ code”
Reference:
“Radioactive beam production with in-flight separators", O.T. and D.Bazin, NIM B (2008) 4657-4664.
• The code operates under MS Windows environment and provides a highly user-friendly interface.
• It can be freely downloaded from the following internet addresses: http://lise.nscl.msu.edu
• The program LISE++ is designed to predict the intensity and purity of radioactive ion beams (RIB) produced by In-flight
separators.
• The LISE++ name (2002) is borrowed from the well known evolution of the C programming language, and is meant to indicate that the program is no longer limited to a fixed configuration like it was in the original “LISE” program, but can be configured to match any type of device or add to an existing device using the concept of modular blocks.
• The LISE code (1985) was named after the fragment separator LISE.
• The main functions of the program: predict the fragment separator settings necessary to obtain a specific RIB; predict the intensity and purity of the chosen RIB; simulate identification plots for on-line comparison; provide a highly user-friendly graphical environment; allow configuration for different fragment separators.
• The program is constantly expanding and evolving
from the feedback of its users around the world.
• The LISE++ package includes configuration files for most of the existing fragment and recoil separators found in the world.
• Many “satellite” tools have been incorporated into the LISE++ framework (will be discussed in Friday)
http://www.nishina.riken.jp/RIBF/BigRIPS/intensity.html
BigRIPS @ RIBF
Why LISE++ ? Where is it used? (1)
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So, for the in-flight RIB facilities with the PAC system for proposals
LISE++ configurations files have been developed by local fragment separator groups.
“how to prepare a technical part of the proposal ?”
A1900 @ NSCL
http://www.nscl.msu.edu/exp/propexp/procedure
Why LISE++ ? Where is it used? (2)
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So, for the in-flight RIB facilities with the PAC system for proposals LISE++ configurations files have been developed by local fragment separator groups
http://pro.ganil-spiral2.eu/laboratory/experimental-areas/lise/technical-
informations/lise-_configuration/lise/
LISE @ GANIL
How to set up the FRS –
From SIS extraction of primary beam to isotope identification
http://web-docs.gsi.de/~weick/frs/frs-steps.html
FRS @ GSI
Why LISE++ ? Where is it used? (3)
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in-flight RIB facilities without the PAC system for proposals
ACCULINNA & COMBAS @ FLNR
RESOLUT @ FSU
MARS @ TAMU
The Content of the Lectures
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Production of radioactive ion beams, I
(27 August 14:30-16:00)
Production of radioactive ion beams, II
(28 August 09:30-11:00)
Recap-session LISE++
(30 August 11:30-13:00)
1. Introduction to RIB production
2. Production Area
3. Separation
4. Identification
5. Production of new isotopes
6. LISE++ : Utilities
7. Radioactive beam physicist task
Acknowledgements (as Copyright issue)
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Would like to thank MSU colleagues
D. Bazin, T. Baumann, D.J. Morrissey, A. Stolz,
T. Kubo (RIKEN), H.Weick (GSI)
and especially FRIB Chief Scientist B.M. Sherrill
for providing materials to prepare these lectures
Discussions
with B.M.Sherrill (MSU), D.J. Morrissey (MSU) and A.Gade (MSU)
are very appreciated
1. Introduction to Production of Rare Ion Beams
Rare Isotope Science and Applications
How do we make rare isotopes?
Production Mechanisms
High energy
Low energy
Production Cross Sections
Rare Isotope Production Techniques
ISOL
In-Flight
Fragment separators
Methods: Pros and Cons
Rates comparison
In-Flight facilities
Brief “Summary”
New territory to be explored
with next-generation rare
isotope facilities
The availability of rare isotopes over time
Nuclear Chart in
1966
Less than 1000
known isotopes
blue – around 3000 known isotopes
Black squares are the around 260 stable isotopes found in nature (> 1 Gy)
Rare Isotope Science and Applications
Properties of nucleonic matter
– Classical domain of nuclear science
– Many-body quantum problem: intellectual overlap to mesoscopic
science – how to understand the world from simple building blocks
Nuclear processes in the universe
– Energy generation in stars, (explosive) nucleo-synthesis
– Properties of neutron stars,
EOS of asymmetric nuclear matter
Tests of fundamental symmetries
– Effects of symmetry violations are
amplified in certain nuclei
Societal applications and benefits
– Bio-medicine, energy, material
sciences, national security
How do we make rare isotopes?
Lithium-7
3 protons, 4 neutrons
Suppose we want to study Lithium-11
3 protons, 8 neutrons
B.Sherrill
Creation of new isotopes
11-Lithium 18-Oxygen Collision
To use this mechanism (projectile fragmentation),
an 18O nucleus is accelerated to a velocity
of greater than around 50 MeV/u.
B.Sherrill
Cross Section for Production
rt rb 2
600 mb
Beam Target
rt rb
18O
17N
16C
15B
14Be
13Li 12Li 11Li
One nucleon
removal
Around 50 mb
(light nuclei)
P ≈ 5%
2n removal
5 mb
P = .5%
And so on
Rule of thumb
.1 x for each
neutron removed
Actual: 16O +12C interaction cross section:
1000 mb (measured at 970 MeV/u)
Note: Above around 300 MeV/u the
interaction length is shorter than the
electronic stopping range of the 16O
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B.Sherrill
Production Mechanisms – High Energy
Fragmentation (used at NSCL, GSI, RIKEN, GANIL, FRIB)
o Projectile fragmentation of high energy (>50 MeV/A) heavy ions
o Target fragmentation with high energy massive ion.
Spallation (ISOLDE, TRIUMF-ISAC, EURISOL, SPES, …)
o Name comes from spalling or cracking-off of target pieces.
o Major ISOL mechanisms, e.g. 11Li made from spallation of Uranium
Fission (HRIBF, ARIEL, ISAC, JYFL, …)
o There is a variety of ways to induce fission (photons, protons,
neutrons [thermal, low, high energy])
o The fissioning nuclei can be the target (HRIBF, ISAC) or
the beam (GSI, NSCL, RIKEN, FAIR, FRIB)
Coulomb Fission (GSI) o At beam velocities of > 200 MeV/u the equivalent photon flux is so high
the GDR excitation cross section is many barns
Charge Exchange (GSI, NSCL, FRIB)
o a neutron or proton can change its charge with a proton or neutron;
cross sections can be ≈mb at >100 MeV/u
Production Methods – Low Energy
(p,n) (p,nn) etc.
o Ep < 50 MeV
o Used for the production of medical isotopes
o Selective, large production cross sections (100 mb), and intense
(500 mA) primary beams
o Used at HRIBF(ISOL), LLN (ISOL), ANL (in-flight) and Notre Dame (in-flight), Texas A&M (in-flight with MARS, e.g. 23Al)
Fusion-Evaporation
o Low energy 4-15 MeV/A and “thin” targets (mg/cm2)
o Selective with fairly large production cross sections
o Used for example at JINR, ANL(in-flight), JYFL (Jyväskylä)
Fusion-Fission
o 238U+12C (basis of Laser acceleration idea D. Habs et al.)
o 238U(24MeV/u) +9Be @ LISE3.GANIL.FR
Low Energy - Continued
Multi-Nucleon Transfer reactions (two body final state)
o Significant cross section between 10 - 50 MeV/A
o High production of nuclei near stability.
o Multi-nucleon reactions can be used to produce rare or more
neutron rich nuclei.
Deeply inelastic reactions (10 - 50 MeV/u range)
o Deep inelastic - KE of the beam is deposited in the target.
Products are emitted away from the beam axis.
o Was used to first produce many of the light neutron rich nuclei
o Is used to study neutron rich nuclei since the products are “cooler”
and fewer neutrons are evaporated than in fusion reactions.
o Large cross sections for production of some exotic isotopes
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Fission Cross Sections
Low energy fission can lead
to higher yields for certain
nuclides.
This is the basis of the
electron driver upgrade
of the TRIUMF (ARIEL).
25
Projectile fragmentation
More details in the
“Production area”
lecture
Simple nuclear reactions provide a broad range of nuclei
• General features of the reactions are well-known but some details are not • Projectile fragments are produced at nearly the speed of light
• Projectile fragments: Rapid physical separation of fragment in a magnetic system
Requires: Z, A, and q identification/separation in 0o spectrometer
A few beams or
targets produce a broad range of
products
Summary of High Energy Production Mechanisms
http://www-win.gsi.de/charms/
Accelerators
The particle accelerator used for production
is often called the “driver”
Types
– Cyclotron (NSCL, GANIL, TRIUMF (proton driver), HRIBF
(proton driver), RIKEN RIBF)
– Synchroton (GSI, FAIR-GSI)
– LINAC (LINear ACcelerator) (FRIB, ATLAS – ANL)
– Others like FFAGs (Fixed-Field Alternating Gradient) are
currently not used
Main Parameters
– Top Energy (e.g. FRIB will have 200 MeV/u uranium ions)
– Particle range (TRIUMF cyclotron accelerates hydrogen,
hence is used for spallation)
– Intensity (1pμA = 6.25 x 1012 /s)
– Beam Power = Intensity x Beam Energy (so FRIB 400 KW)
– Emittance of primary beam
LISE++
Types of ISOL Ion Sources
P. Butler
Beam into page
Target
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For details : “Production and acceleration of rare-isotope beams” by Giovanni Bisoffi ISOL & In-flight methods, ion sources, accelerators et al.
http://iks32.fys.kuleuven.be/f iles/euroschool/2012_Giovanni_Bisoffi.zip
I = Ib Tuseable ediff edes eeff eis_eff eaccel_eff
H. Ravn
- production cross section
Ib - beam intensity
Tuseable - usable target thickness
ediff – diffusion efficiency
edes – desorption efficiency
eeff – effusion efficiency
e is_eff - ionization efficiency
eaccel_eff - acceleration efficiency
Production is only one part of the equation
target
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https://groups.nscl.msu.edu/frib/rates/FRIB_rates_readme.pdf
Some efficiency examples* can be found in
* from Georg Bollen
ISOL: beam-target choice
Giovanni Bisoffi
HRIBF example will be used for comparison between In-Flight & ISOL
In-Flight : Basic principle of operation
1. P
rod
uc
tion
2. Separation
3. Id
en
tifi
ca
tio
n
Production, Separation, Identification -- our next lectures
In-flight RIB yields
1. P
rod
uc
tion
Are
a
2. Separation
3.
Ide
nti
fic
ati
on
Y number of registered events
σ production cross section
Nt number of target atoms
Nt = dt Mt / NA
where
dt target thickness
NA Avogadro number
Mt atomic mass number
I beam intensity
t duration of measurement
e t efficiency transmission at target
e s efficiency transmission through separator
e i identification efficiency
Y = I t Nt σ et es ei
e t efficiency transmission at target • lost of primary beam and fragments of interest due to
reaction in target and stripper
• charge state factor after target (stripper) • Gain due to secondary reactions
e s efficiency transmission through separator • lost of fragments of interest due to reaction in materials
located in the separator • charge state factor after materials
• Angular acceptance
• Momentum selection • Wedge selection
• Other selections
e i identification efficiency • lost of fragments of interest due to reaction in detectors • Live time (as well pile-ups)
will be discussed in details in the next chapters
In-Flight Production Example: NSCL’s CCF
fragment yield after target fragment yield after wedge fragment yield at focal plane
Example: 86Kr → 78Ni K500
K1200 A1900
production
target
ion sources
coupling
line
stripping
foil
wedge
focal plane
p/p = 5%
transmission
of 65% of the
produced 78Ni
86Kr14+,
12 MeV/u
86Kr34+,
140 MeV/u
1 KW
D.J. Morrissey, B.M. Sherrill, Philos. Trans. R. Soc. Lond. Ser. A. Math. Phys. Eng. Sci. 356 (1998) 1985
• Fast beams (S800, Mona, …)
• Stopped beams (LEBIT, BECOLA) • Reaccelerated beams with ReA3
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Rare isotope beams delivered to experimental
vaults/areas for science with
Exotic Beams Produced at NSCL
More than 1000 RIBs have been made – more
than 830 RIBs have been used in experiments
12 Hours for a primary beam change; 3 to 12 hours for a secondary beam
Fragment separator generation
D.J.Morrissey
First Experiments – LBL BEVALAC [late 70’ s]
First Generation, used existing device: LISE @ GANIL
Second Generation, construct specific device:
A1200 @ NSCL, K=Kaccel
superconducting, begins beamlines
FRS @ GSI, K=Kaccel
full acceptance, begins beamlines
RIPS @ RIKEN, K= 1.65 Kaccel
large acceptance
Third Generation, construct improved high-resolution device:
LISE3 @ GANIL, post selection in Wien filter
A1900 @ NSCL, K=1.6 Kaccel superconducting, begins beamlines
Fourth Generation – preselection before high resolution separator:
A1900 & S800 beamline @ NSCL – recently tested
BigRIPS @ RIKEN – just finished, recently tested
SuperFRS @ GSI – in design
A2400 @ FRIB – in design
Fragment: 11Li, A/q = 3.67
Beam: 18O, A/q = 2.25 ratio 1.63
K1200 accelerator A1900 separator
“K” – proton kinetic energy in MeV
(e.g. K500, K1200, A1200, A1900)
E = K q2 / A
Maximum bending power is related to K
K = (e B)2 / (2 m0)
Better separation of the selected nuclei
Good beam quality (emittance)
Small beam energy spread
Post-acceleration allows to vary RIB energy
Can use chemistry (or atomic physics) to limit the
elements released
2-step targets provide a path to MW targets
Pros for ISOL & In-Flight
Provides beams with energy near that of the primary beam
Individual ions can be identified
Luminosity (intensity x target thickness) gain of 10,000
(one week experiment* = 3 x 10-18 barn)
Efficient (can be close to 100%)
Fast (100 ns)
Chemically independent separation
Production target is relatively simple
Broad range of RIBs
In-flight: GSI
RIKEN
NSCL
FRIB
GANIL
ANL
RIBBAS
…
ISOL: HRIBF
ISAC
SPIRAL
ISOLDE
SPES
EURIOSOL
….
[email protected] 44 * recent experiment : O.T. et. al., PRC 87, 054612 (2013)
Cons for ISOL & In-Flight
Very low cross section for n-rich of some elements
Large energy and transverse emittances
Fixed high energy
Contamination by secondary products
large size and cost of fragment separators
In-flight: GSI
RIKEN
NSCL
FRIB
GANIL
ANL
RIBBAS
…
ISOL: HRIBF
ISAC
SPIRAL
ISOLDE
SPES
EURIOSOL
….
Finite time to get the RIB out of source (t1/2 > 10 ms)
Some elements are tough to produce
Large cost of high-temperature production target
Chemistry is involved
Attempt to estimate ISOL & In-Flight yields with LISE++
HRIBF : p(40MeV, 5uA) + 238U
Assumptions for ISOL method: Total efficiency: 10%
Extraction time: 50 ms
NSCL : from the beam list
for Ca isotopes 82Se(140MeV/u, 35 pna)
238U(80MeV/u, 0.2 pna)
for Kr isotopes 136Xe(120MeV/u, 2 pna)
238U(80MeV/u, 0.2 pna)
Details of these calculations will be discussed in one of the next lectures
ISOL & In-Flight : Ca isotopes
“Delay” block Total efficiency: 10%
Extraction time: 50 ms
X-axis : Mass number
Y-axis : rate (pps) TF – target fragmentation
calculated with EPAX3
HRIFB NSCL
HRIFB vs. NSCL
Last neutron-rich Calcium
isotopes 57,58Ca have been
observed @ NSCL in
projectile fragmentation of 76Ge and 82Se
ISOL & In-Flight : Kr isotopes
“Delay” block Total efficiency: 10%
Extraction time: 50 ms
X-axis : Mass number
Y-axis : rate (pps) TF – target fragmentation
calculated with EPAX3
HRIFB NSCL
HRIFB vs. NSCL
Last neutron-rich Krypton
isotopes 98-101Kr have been
observed @ GSI & RIKEN in
in-flight fission of 238U
Future for
Two-step process?
1. ISOL fission
2. In-flight PF
World view of rare isotope facilities
Black – production in target
Magenta – in-flight production
Ariel
In-Flight facilities
Facility Location Driver Primary Energy Typical
intensity
Fragment
separator
GANIL France 2 separated sector
cyclotrons
Up to 100A MeV 36S 1013 pps
48Ca 2 1012 pps
SISSI +
ALPHA
GSI Germany Linac + Synchrotron Up to 2A GeV 1010 ppspill FRS
NSCL/MSU USA 2 coupled
superconducting
cyclotrons
Up to 200A MeV 40Ar 5 1011 pps
(2 kW)
A1900
RARF
RIKEN
Japan Ring cyclotron Up to 100A MeV 40Ar 5 1011 pps RIPS
RIBF RIKEN Japan 3 Ring Cyclotrons 350A MeV 5 1012 pps 238U
(10-100 kW)
BigRIPS
FAIR Germany SIS 100 Synchrotron Up to 2A GeV 1012 ppspill 238U
Super FRS
F RIB USA LINAC Up to 200A MeV 400 kW A2400
What New Nuclides Will Next Generation Facilities Produce?
They will produce more
than 1000 NEW isotopes
at useful rates (4500
available for study)
Theory is key to making
the right measurements
Exciting prospects for
study of nuclei along the
drip line to mass 120
(compared to 24)
Production of most of the
key nuclei for
astrophysical modeling
Harvesting of unusual
isotopes for a wide range
of applications Rates are available at
http://groups.nscl.msu.edu/frib/rates/
Major US Project – Facility for Rare Isotope Beams, FRIB
Funded by DOE Office of
Science & MSU
– 2022 completion,
– 2020 early completion
Key Features:
400kW beam power (5 x1013
238U/s)
• Efficient acceleration
(multiple charge states)
Separation of isotopes
in-flight:
– Fast development time
for any isotope
–Suited for all elements
and short half-lives
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Facility for Rare Isotope Beams
The Total Project Cost for FRIB is $730M, of which $635.5M will be
provided by DOE and $94.5M will be shared by the community
SRC: World Largest (Heaviest) Cyclotron
Remind, that “K” is proton energy.
RIBF 238U energy is 345 MeV/u
[email protected] 58 Courtesy of T.Kubo
Facility for Antiproton and Ion Research
Beams at 1.5 GeV/u
1012/s Uranium
Research
– Compressed matter
– Rare isotopes
– Antiproton
– Plasma
– Atomic physics
Completion of the first stages
are planned around 2018 http://www.fair-center.de/index.php?id=1
linac
Experiment building
Beam line [for acceleration]
Beam line [for experiment]
Target building
In-Flight Fragmentation linac
ISOL linac
Future plan
200MeV/u (U)
Stripper
SC ECR IS
Cyclotron K ~ 100
Fragment Separator
Charge Breeder
SCL RFQ
RFQ
SCL
SCL
Low energy experiments
ISOL
target
In-flight
target
μ, Medical
research
Atom trap
experiment
H2+ D+
KoRIA Schematic Layout
Seung Woo Hong
Brief Summary: The Five-Minute Rap Version
Rare Isotope Rap by Kate McAlpine (also did the LHC Rap)
B.Sherrill
Nuclide discovery project
from Michael Thoennessen http://www.nscl.msu.edu/~thoennes/isotopes/
Discovery papers
Table of top 1000 (co)authors
Table of top 250 first authors
Table of top 25 labs
Table of countries
Journals and publishers
Discovery of exotic nuclei:
past, present and future
GENCO Colloquium
GSI, February 28, 2013
Terra Incognita: exploring the limits of nuclear existence
Figure: Chart of nuclei [1] (element or proton number Z versus neutron number N): stable nuclei along the valley of
stability are shown in black, isotopes that have been detected at least once on Earth are shown in blue, and the large terrain of unknown nuclei is shown in red. The estimated paths for the r- and rp-
processes for explosive nucleosynthesis in the cosmos are indicated by solid lines. [1] “Isotope Science Facility at Michigan State University”,
MSUCL-1345, November 2006
The limits of nuclear stability provide a key benchmark of nuclear models:
Exploring nuclei with unusual properties Exploring changes in shell structure Exploring nuclear shapes
The context of astrophysics:
What is the origin of the heavy elements? Understanding the r-process abundance patterns
of elements (see Figure)
Production mechanism study to explore Terra Incognita: reaction choice, production cross sections, momentum distributions,
Secondary beam intensities. Planning new experiments, set-ups (F-RIB, RIBF, FAIR)
PR
The study of properties (masses, lifetimes, and properties of excited states) of the most exotic isotopes continues to be one of the important tasks in experimental nuclear physics. The first step in the study of a new exotic nucleus is its observation, which for neutron-rich nuclei demonstrates its stability with respect to particle emission.
Nuclear Landscape
• Chart of the
nuclides
• Black squares
are the 263
stable isotopes
found in nature
(> 1 Gy)
• Dark green
closed area is
the region of
isotopes
observed so far.
• The limits are
not known.
Open Questions in the Search for the Limits
Open Questions:
How many elements can exist? We are up to element 118 and
counting.
Are there long-lived superheavy elements, with half lives of
greater than 1 year?
Where are the atoms of the various elements formed in nature?
What makes atomic nuclei stable? We know Strong and
Electroweak forces are involved, but don’t understand how in
detail. The inability to answer this question is reflected in our
inability to answer the first three questions.
History of Element Discovery
[email protected] , Slide 67
Democritus –
idea of atoms
India
Babylonia
Egypt
China
Copper Age
1700+ Rise of modern chemistry –
Dalton’s Atomic Theory
Source: Mathematica + Wikipedia
The history of element discovery 1200-2010
Time of the Alchemists
Chemistry
Dalton’s Atomic Theory
Cavendish, Priestly, Scheele, …
Mendeleev’s
Periodic Table
Particle
Accelerators
Reactors
Future?
Discovery of Isotopes
[email protected] , Slide 69
Fredrick Soddy – Credited with discovery of isotopes
– Extremely talented chemist who began his career at McGill
as a lecturer in 1900
– Rutherford came to McGill at the same time. Rutherford
needed the help of a Chemist to try to understand
radioactivity.
– Rutherford won 1908 Nobel prize "for his investigations into the disintegration of the elements, and the chemistry of
radioactive substances” (identified α and β radioactivity)
Isotopes
– In 1910 Soddy found that the mass of lead from thorium
decay differed from lead from uranium decay
– He realized that atoms of a given elements must come in different forms that he called isotopes (Greek for “at the
same place”) JJ Thompson in 1913 showed the first direct
evidence – Ne isotopes in cathode ray tube.
– "Put colloquially, their atoms have identical outsides but
different insides.” – Soddy Nobel Prize Lecture
– Won Nobel Prize in 1921 for discovery of isotopes
First Synthesis of Radioactive Isotopes
[email protected] , Slide 70
– The first artificial isotopes were
produced by F Joliot and I Curie (Nature,
10 Feb 1934 ) by bombarding B, Al, Mg
with alpha particles from Po
– “We propose for the new radio-isotopes
formed by the transmutation of boron,
magnesium and aluminum, the names
radionitrogen, radiosilicon,
radiophosphorus”
– For this discovery, Curie and Joliot won
the Nobel Prize in chemistry in 1935
New isotope discoveries per year
M.Thoennessen and B.Sherrill, Nature 473 (2011) 25
New territory to be explored
with next-generation rare
isotope facilities
The availability of rare isotopes over time
Nuclear Chart in
1966
Less than 1000
known isotopes
blue – around 3000 known isotopes
Black squares are the around 260 stable isotopes found in nature (> 1 Gy)
What New Nuclides Will Next Generation Facilities Produce?
They will produce more
than 1000 NEW isotopes
at useful rates (4500
available for study)
Theory is key to making
the right measurements
Exciting prospects for
study of nuclei along the
drip line to mass 120
(compared to 24)
Production of most of the
key nuclei for
astrophysical modeling
Harvesting of unusual
isotopes for a wide range
of applications Rates are available at
http://groups.nscl.msu.edu/frib/rates/
How many isotopes might exist?
[email protected] , Slide 74
Estimated Possible:
Erler, Birge, Kortelainen,
Nazarewicz, Olsen,
Stoitsov, Nature 486,
509–512 (28 June 2012) ,
based on a study of EDF
models
“Known” defined as
isotopes with at least
one excited state known
(1900 isotopes from
NNDC database)
Represents what is
possible now
The Number of Isotopes Available for Study
at FRIB (next generation facilities)
[email protected] , Slide 75
Estimated Possible:
Erler, Birge, Kortelainen,
Nazarewicz, Olsen,
Stoitsov, Nature 486,
509–512 (28 June 2012) ,
based on a study of EDF
models
“Known” defined as
isotopes with at least
one excited state known
(1900 isotopes from
NNDC database)
For Z<90 FRIB is
predicted to make > 80%
of all possible isotopes
Prediction of the limits of the nuclear landscape
[email protected] , Slide 76
J. Erler et al., Nature 486, 509 (2012)
265 stable isotopes, 3100 observed, more like 2000 “known”
Z=8-14, 1970 - June, 2007
Figure. The region of the chart of nuclides
under investigation in this work.
1970: Artukh, A. G. et al., New isotopes 21N, 23O, 24O and 25F, produced in nuclear reactions with heavy ions. Phys. Lett. 32B, 43–44 (1970).
1990: Guillemaud-Mueller, D. et al., Particle stability of the
isotopes 26O and 32Ne in the reaction 44 MeV/nucleon 48Ca+Ta. Phys. Rev. C 41, 937–941 (1990).
1997: Tarasov, O. et al., Search for 28O and study of neu-tron-rich nuclei near the N = 20 shell closure. Phys. Lett. B 409, 64–70 (1997).
1999: Sakurai, H. et al., Evidence for Particle Stability of 31F and Particle Instability of 25N and 28O. Phys. Lett. B 448 180 (1999).
2002: Notani, M. et al. New neutron-rich isotopes, 34Ne, 37Na
and 43Si, produced by fragmentation of a 64 A MeV 48Ca
beam. Phys. Lett. B 542, 49–54 (2002).
2002: Lukyanov, S. M. et al. Experimental evidence for the particle stability of 34Ne and 37Na. J. Phys. G: Nucl. Part. Phys. 28, L41–L45 (2002).
2007: Tarasov, O. B., et al., New isotope 44Si and systematics
of the production cross sections of the most neutron-rich
nuclei. Phys. Rev. C, in press (2007).
FLNR
GANIL
GANIL
RIKEN
RIKEN
GANIL
MSU
Neutron-rich side
Z< 100
proton-rich
side (100Sn, 45Fe, 48Ni, 60Ge etc) omitted:
48Ca (140MeV/u) + W (NSCL@MSU)
a) New isotope: 44Si
O.T. et al., Phys.Rev. C 75, 064613 (2007)
New isotopes 40Mg, 42Al, 43Al
T.Baumann et al.,Nature(London) 449, 1022 (2007)
2009 : 76Ge (130 MeV/u)
Phys.Rev.Lett. 102, 142501 (2009) : New isotopes, Evidence for a Change in the Nuclear Mass Surface
Phys.Rev.C. 80, 034609 (2009) : Set-up, cross sections, momentum distributions
NIM A 620, 578-584 (2010) : A new approach to measure momentum distributions
50Cl, 53Ar, 55,56K, 57,58Ca, 59,60,61Sc, 62,63Ti, 65,66V, 68Cr, 70Mn
Newly-developed 82Se (139 MeV/u)
64Ti, 67V, 69Cr, 72Mn 70Cr 1event & 75Fe 1event
Beam E (MeV/u) I (pna) N/Z
82Se 139 35 1.412
76Ge 130 20 1.375
N / Z=2
O.T. et al., Phys. Rev. C 87, 054612 (2013)
[email protected] 88 Courtesy of T.Kubo
“Next” Calcium isotopes
76Ge approved proposal
from MSU @ RIKEN
Intensity factor 2 Target thick. factor 10
Secondary reactions factor 55 (for 60Ca)?
Intensity: Factors for production of new isotopes
Y = I t Nt σ et es ei
* reduced, Y=1 , assuming e t e s e I equal to 100%, 100% time just for one production run
** RIKEN : 48Ca 345 MeV/u 150 pnA
Estimated rates
http://groups.nscl.msu.edu/frib/rates/
http://groups.nscl.msu.edu/frib/rates/FRIB_rates_readme.pdf Readme file :
Exploration of unknown neutron-rich region. Next
In action: RIBF @ RIKEN
238U 345 MeV/u, 1 pnA
2019 - 2020: GSI – new isotope production
with pre-separator, 1.5 GeV/u, 1012 pps
2020-2022: FRIB @ MSU
200-250 MeV/ u , 400 kW
Yields per 1 second
A total of 47 primary
beams were used for FRIB
yield analysis. These
cover nearly 90% of the
optimum
primary beams for the
production of all isotopes.
RIBF @ RIKEN 238U 345 MeV/u, 2pnA
GSI ,1.5 GeV/u, 1012 pps
F-RIB @ MSU
200-250 MeV/ u , 400 kW
RIBF beam intensities (2009)
48Ca Kr Xe 238U
FY2008 170 pnA 30 pnA *1 - 0.4 pnA
FY2009 expected 200 pnA 30 pnA *2 10 pnA 5 pnA *3
*1: 1min *2: Limited by e04 CS *3: with SC-ECRIS
U-beam intensity in future (rumor): ~100
pnA
with new injector linac, new 28GHz S.C.
ECR ion source and new stripper
Courtesy of T.Kubo
End of Lecture 5
The next decade is expected to be very
fruitful in production of new isotopes (> 103)
