Kerstin Sonnabend – Michael Hass N-NA06: Nuclear Astrophysics Open questions and issues in nuclear...

Kerstin Sonnabend – Michael Hass N-NA06: Nuclear Astrophysics

Open questions and issues in nuclear astrophysics

Kerstin Sonnabend

Darmstadt, GermanyPresented by:

Michael Hass, Weizmann, Israel

And the role of EURISOL….


CARINAChallenges and Advanced Research In Nuclear Astrophysics

Kerstin Sonnabend

Institut für Kernphysik, TU Darmstadt, Germany

Carmen Angulo


CARINA activities

Two CARINA workshops organized:– First workshop: „Perspectives in European Nuclear

Astrophysics“, Parador d‘Aiguablava, Girona, Spain, June 8th - 10th, 2005

• 39 participants from ten countries• five review talks on astrophysical models (explosive burning and AGB/quiescent

burning), nuclear models for astrophysics, experiments with RIB at LSF, and experiments at small facilities

• short talks and discussions in working group sessions (plenary)• summary of the conclusions:

– large variety of problems needs large variety of methods– specific tools needed for different nucleosynthesis scenarios– small-scale facilities as ‚feeders‘ to large-scale facilities– establish a ‚flagship‘ ISOL-type facility for nuclear astrophysics with gas

targets, recoil separator, spectrometer, solid-state detectors, and -ray detection systems available

– find tentative lists of astrophysical sites and nuclear models for nuclear astrophysics


CARINA activities

– Second workshop: „Frontier Research in European Nuclear Astrophysics“, Spaulomont, Spa, Belgium, April 25th - 28th, 2007

• 37 participants from 13 countries• 21 talks and five discussions (plenary)• workshop explored opportunities for new European

facilities– agreement that additional facilities, specifically for nuclear astrophysics, are

warranted and needed– lively discussion over strategy: should it be a dedicated nuclear

astrophysics proposal, or complementary to a general nuclear physics proposal?

– possibilities include: nuclear astrophysics labs network, an underground accelerator, a dedicated nuclear astrophysics separator for capture reactions, reclamation of radioisotopes, ...


Continuation of the CARINA network within FP7

JRA-9 (P.J. Woods & M. Hass)

NA-15 (S. Marrone & F. Käppeler)

NA-16 (K. Sonnabend & C. Angulo)

and tasks of N-NA07 (Theory) related to Nuclear Astrophysics


N-NA06:Nuclear Astrophysics

Coordinator: K. Sonnabend, Darmstadt, Germany• Task 1 – Explosive Nucleo-Synthesis P.J. Woods, Edinburgh, UK, M. Hass, Weizmann, Israel• Task 2 - Reactions at Low Temperatures K. Sonnabend, Darmstadt, Germany • Task 3 - Nucleo-Synthesis in neutron capture processes S. Marrone, INFN Bari, Italy• Task 4 – Nuclear astrophysics annual meeting

ENSAR meeting,Frankfurt, December 12th, 2007


Novelty & Innovation

Concentrate on special issues of interdisciplinary field of research

Provide individual solutions for problems of special issues

Use already available infrastructures

Find and enhance synergetic effects

Integrate it all in annual meetings


Task 2 - Reactions at Low Temperatures K. Sonnabend, Darmstadt, Germany

• e.g. - Solar reactions• Not necessarily RIB • Smaller laboratories (local)• Underground possibilities (“a la LUNA”)


The SNO (Sudbury Neutrino Observatory) Experiment

A D2O Detector

e + d p + p + e-

charge current

x + d p + n + x

neutral current

“SMOKING GUN”!!

YES!!PRL 87, 071301 (2001)PRL 89, 011301 (2002)PRL 92, 181301 (2004)

Only e

ll flavors

x +e- x+e- ElasticMostly e


Current status of S17 - direct capture - determinations

Recognized need for a new WI measurement at low energy…In progress… 7Be(p,)8B “saga” not over yet…..


By Courtesy of T. MotobayashiF. Schümann et al. Phys. Rev. C 73, 015806 (2006)

Summary of Coulomb Dissociation S17 Results


S17 astrophysical factor - ANC - (R. Tribble)

(7Be,8B) proton transfer at 12 MeV/u two targets:10B: S17(0) = 18.4 2.5 eVb (PRL ’99)14N: S17(0) = 18.0 1.8 eVb (PRC ’99;

PRC ‘06)

13C(7Li,8Li)12C at 9 MeV/u using mirror symmetry (PRC ‘03)

S17(0) = 17.6 1.7 eVb

Average: S17 = 18.2 1.7 eVb Average: S17 = 18.2 1.7 eVb

S.

p p3 / 2 1 / 21 7

2 203 8 6

eV b

fm C C

-1

8B breakup

Transfer

JLM S17=17.4±2.1 eVb

“standard” S17=19.6±1.2 eVb

Ray S17=20.0±1.6 eVb

Determine C2 by three approaches

Average: S17=18.7±1.9 eVb PRC ‘04


Results and Fits

S34(0) = 0.53(2)(1) keV-b

B.S. Nara Singh et al.,

Phys. Rev. Lett. 93, 262503 (2004).

New LUNA Activity Result -Phys. Rev. Lett. 97, 122502 (2006)

No compelling need to assumeSystematic difference betweenprompt and activity determinations

• RMS ERNA in Bochum• Seattle


Dedicated experiments to measure the 7Be EC lines: Borexino etc…

SNO


b.- Primordial 7Li –SBBN (A. Coc, Orsay)

Kerstin Sonnabend – Michael Hass N-NA06: Nuclear Astrophysicswww.cern.ch/n_TOF

n_TOF/Astrophysics:present & future

[email protected]

Task 3 - Nucleo-Synthesis in neutron capture processes S. Marrone, INFN Bari, Italy

Kerstin Sonnabend – Michael Hass N-NA06: Nuclear Astrophysicswww.cern.ch/n_TOF [email protected]

Nuclear Astrophysics

NNrr = N= Nsolarsolar – N – Nss

Residual MethodResidual Method

NNrr = N= Nsolarsolar – N – Nss

Residual MethodResidual Method

Re/Os cosmo-Re/Os cosmo-chronometerchronometer

Red Red GiantsGiants

SupernovaSupernovaee


The n_TOF-PhThe n_TOF-Ph22 experiments experiments20020088 and beyond and beyond

Capture measurementsMo, Ru, Pd stable isotopes

Fe, Ni, Zn, and Se (stable isotopes)79Se

A≈150 (isotopes varii)

234,236U, 231,233Pa

235,238U

239,240,242Pu, 241,243Am, 245Cm

r-process residuals,isotopic patterns in SiC grains

s-process nucleosynthesis in massive starsnuclear data needs for structural materials

s-process branching pointslong-lived fission products

Th/U nuclear fuel cycle

standards, conventional U/Pu fuel cycle

incineration of minor actinides

(*) endorsed by CERN Isolde-n_TOF Committee, execution in 2008

[email protected]/n_TOF


The second n_TOF beam line

Spallation TargetSpallation Target

NewExperimentalArea (EAR-2)

present EAR-1 (at 185 m)

~ 20 m~ 20 m

• present EAR-1: present EAR-1: Flight path ~Flight path ~185 m, Neutron Flux185 m, Neutron Flux~10~1066 n per proton bunch; n per proton bunch; High resolution in neutron energy. High resolution in neutron energy.

• new EAR-2: Flight path new EAR-2: Flight path ~~20 m at 9020 m at 90° with respect to p-beam; neutron flux ° with respect to p-beam; neutron flux enhanced by factor ~100; drastic reduction of backgrounds.enhanced by factor ~100; drastic reduction of backgrounds.

• present EAR-1: present EAR-1: Flight path ~Flight path ~185 m, Neutron Flux185 m, Neutron Flux~10~1066 n per proton bunch; n per proton bunch; High resolution in neutron energy. High resolution in neutron energy.

• new EAR-2: Flight path new EAR-2: Flight path ~~20 m at 9020 m at 90° with respect to p-beam; neutron flux ° with respect to p-beam; neutron flux enhanced by factor ~100; drastic reduction of backgrounds.enhanced by factor ~100; drastic reduction of backgrounds.

Proton Proton BeamBeam

[email protected]/n_TOF


• Identification of the key reactions, including specification of the energy range and precision required for future experimental studies (leading institute: Barcelona).

• Identification of the key technical developments required to deliver the highest priority radioactive beams to measure these reactions including exchange of technical ideas and coordination, of how and where developments should be best achieved (leading institute: Weizmann).

• Identification of the key characteristics of design and construction of novel detector and spectrometer systems to measure these reactions including exchange of technical ideas and coordination of single activities (leading institute: Edinburgh).

• Determination of key features of nuclear properties, nuclear reactions, and the nuclear equation of state for astrophysical simulations and their experimental and/or theoretical verification (leading institute: Basel).

Task 1 – Explosive Nucleo-Synthesis


Secondary neutrons + fission

BUT

Also light RIB’s


Fusion Reactions in the Sun:The CNO cycle

14O

17F

(,p)

…..

Proposed at GANIL


Mass accretion from a companion into a neutron star (black hole).

Role of 14O, 15O and 18Ne in the physics

of x-ray bursts

4He(15O,)19NEM. Wiescher et al. Erice Conference, 2007

J.L. Fisker et al., arXiv:astro-ph/070241


X-Ray Bursts and the “rp” process

The rp process and x-ray bursts - site of nucleo-synthesis

Courtesy of Joint Inst. For Nuclear Astrophysics (US)


ISOLDE experiment IS424 (Sept. ’07): (in collaboration with P.J. Woods et al.).

Recent Experiments (in progress)

The use of a 17F beam from the upgraded REX-ISOLDE facility to study the astrophysically important 14O(α,p)17F reaction in time reverse kinematics.

• REX-ISOLDE + MINIBALL• Only ~ 103 17F/s

On-line data of p- coincidences –

Indicating the 1st excited state of 17F


GANIL experiment – accepted by GANIL PAC : (in collaboration with Marialuisa Aliotta et al.)

Plan to investigate the direct 14O(,p)17F reaction at four different energies

in the energy region Ecm = 1.0-2.5 MeV

Calculated total S(E) factor.

Constructive (+) and destructive (-)

interference between the Jpp=1-

6.15 MeV state and the direct l=1

partial wave contribution are shown.


14N(d,2n)14O cross section and yield 14N(d,n)15O cross section and yield for a 2 mA deuteron beam for a 2 mA

deuterons beam

But, extraction of atomic oxygen…

Long-learned lesson:

“orders-of-magnitude improvement in sensitivity of measurement –

enhanced understanding and possibilities”.


8Li energies of interestE(8Li [MeV])

3

6


Examples of Reactions with RNB’s for Astrophysics

• 8B(p,)9C

• 8B(,p)11C

• 9C(,p)12N

• 11C(p,)12N


Important experimental and theoretical work has addressed the CNO cycle……..e.g. 14N(p,)15O (see: Schroeder et al. 1987; Angulo et al. 2001)

CNO, Ne-Na, Mg-Al Cycles

Runkle et al. 2002, Phys Rev C 66Formicola et al. 2004, Phys. Lett. B. 591 Runkle et al. 2005, Phys Rev C 94

…. and of the hotter cycles of H-burning:

e.g. for reacions on O isotopes and Na (leading to Mg-A)

Fox et al. 2004, Phys. Rev. Lett. 93: 17O+pRowlad et al. 2004 Phys Rev. Lett 93: 23Na+p

Nucleosynthesis in AGB Stars - Maurizio M. Busso Perugia


RECENT LUNA ACHIEVEMENTS ON CNO

H.P. Trautvetter, ECT Nuclear Astrop. Workshop, (Trento, May 2004)


Ne-Na and Mg-Al ‘cycles’

(p,)

(p,) (p,)

But; effects on higher nuclei (26Al) limited by minimal of 20Neproduction (at least with NACRE): Arnould et al. 1999.


Finances

each specialized task (1 - 3): 50 k€

general annual meetings: 40 k€

support of coordinator: 4 k€

total costs: 194 k€


General considerations to remember: -• It is nuclear structure after all - masses, Q values, lifetimes, reaction theory, …. • Nuclear (astro) physics vs. “modeling” and “standard” astro.• Nuclear astrophysics as “motif” for many RIB facilities. BUT• How much time would a Facility devote to these time-consuming experiments

Kerstin Sonnabend – Michael Hass N-NA06: Nuclear Astrophysics Open questions and issues in nuclear...

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