Poland@ISOLDE Nuclear physics in Poland and plans related to ISOLDE Marek Pfützner ISOLDE Collaboration Committee Meeting, CERN, November 4, 2014

Some history ● 1964 -1991 – Poland was the only country from behind the Iron Curtain having the oficial „observer” status at CERN ● July 1, 1991 – Poland becomes a member of CERN ● early 90’s(?) – Poland became a member of ISOLDE (W. Kurcewicz), after two years the funding was refused  2004: 50 years of CERN – a review by W. Kurcewicz lists 50 papers from ISOLDE experiments coauthored by Polish physicists  Some projects initiated and lead by scientists from Poland (before 2004):  Octupole deformation in actinides (IS322 – W. Kurcewicz)  New neutron-rich isotopes of bismuth, lead, and thallium (IS354 – K. Rykaczewski)  Search for detour transitions in REC decay of 81Kr (IS355 – M. Pfützner)  Coulomb excitations of neutron-rich 88Kr beam (IS424 – J. Iwanicki)

Where we are In 2007 we were about 330 people active in nuclear physics Szczecin University University of Warsaw  Faculty of Physics  Heavy Ion Laboratory  National Centre for Nuclear Research  University of Łódź Maria Curie-Skłodowska University, Lublin  Institute of Nuclear Physics (PAN) Jagielonnian University University of Silesia

Miniworkshop on Polish membership in CERN- ISOLDE Polska@ISOLDE Miniworkshop on Polish membership in CERN- ISOLDE Heavy-Ion Laboratory, Warsaw, May 23, 2014 A consortium „Polska@ISOLDE” was set up and all signatures under the agreement were collected October 1, 2014 Institute of Nuclear Physics, Kraków  Bogdan Fornal National Centre for Nuclear Research, Warsaw  Henryk Mach University of Łódź  Józef Andrzejewski University of Warsaw Heavy Ion Laboratory  Katarzyna Wrzosek-Lipska Faculty of Physics  Marek Pfützner

Cluster transfer reactions for gamma-ray yrast spectroscopy Bogdan Fornal Institute of Nuclear Physics, Polish Academy of Sciences Krakow, Poland A new method for gamma-ray spectroscopic studies of yrast and non-yrast structures in neutron-rich nuclei. It relies on the triton transfer process induced by radioactive beams on a 7Li target. AX + 7Li A+3-xY+α+xn Z Z+1 AX A+1Y 7Li   ~2º n Z Z+1

Gamma spectroscopy of n-rich 98,99Sr nuclei by the incomplete fusion reaction of 98Rb on 7Li: introduction to HIE-ISOLDE studies - experiment with MINIBALL + T-REX at REX-ISOLDE Spokespersons: Bogdan Fornal (Kraków) and Silvia Leoni (Milano) Collaboration: IFJ PAN Krakow – Univ. Milano - SLCJ Warsaw – ISOLDE CERN Reaction: 98Rb+ 7Li @ 2.85 MeV/A IS536 Detection system: MINIBALL + T-REX Coincidencec between g rays and a particles Results: Transfer of tritons into 98Rb, with emission of alpha particles, has a sizeable cross- section as predicted by DWBA calculations. By tagging on a particles one obtains clean g-ray spectra from triton transfer products. Yrast, near-yrast and non-yrast states are populated.

98Rb(60%)/98Sr(40%) (2.84 MeV/u) + 7LiF (1.5 mg/cm2) 99 Sr Y 98 98 Sr Rb 98 IBEAM (98Ru/98Sr) ≈ 2.5 x 104 pps Counting rate: ~0.03 ev/s for a-g (10 k in 4 days) S. Bottoni et al, to be published, and S. Bottoni, PhD Thesis

A new proposal has been submitted to ISOLDE INTC: „Spectroscopy of particle-phonon coupled states in 133Sb by the cluster transfer reaction 132Sn on 7Li: an advanced test of nuclear interactions” Spokespersons: Silvia Leoni and Bogdan Fornal 132Sn + 7Li 133Sb+α+2n P-419 presented tomorrow 2n 133 Sb 132 t Sn

Ultra fast timing studies on exotic nuclei (at ISOLDE) by Henryk Mach, NCBJ for the Fast Timing Isolde Collaborations

Basic Principles of Ultra Fast Timing (Advanced Time-Delayed Method) beta β The range for the measurements is from 30 ps to 30 ns (or longer) by the slope method and down to about 5-10 ps by the centroid shift method, see H.Mach et al. Nucl. Phys. A523 (1991) 197.

IS322 - IS386 Ra - Ac octupole region IS441 134Sn, 136Sn decays IS386 Mn decay IS386 Ba octupole region IS322 - IS386 Ra - Ac octupole region IS414 Mg island of inversion IS441 (2009) 81,82Zn decays IS441 134Sn, 136Sn decays IS317 76Rb to 76Kr decay → 135Sb structure → 136Te: B(E2, 2+ → 0+) 13

Lifetime of the 2+ state in 32Mg Centroid shift technique using a two gamma ray cascade involving beta and 2151-885 keV gammas. Detector calibration for BaF2 at energies close to a 2151 y 885 keV, and cascading via levels of precisely known lifetimes : 88Rb (898-1836 keV) 30Al (1263-2235 keV) 24Na (1369-2754 keV) Triple coincidence: Beta-Ge-Ge Beta-Ge-BaF2(t) Beta-BaF2(t) time spectra gated by Ge energy 14

B(E2)’s for Mg isotopes ATD Low E CoulEx, Timing Intermediate E CoulEx [from O. Niedermaier] Low E CoulEx, Timing Intermediate E CoulEx ATD 15

IS474 IS579 P-429 presented tomorrow

Evolution of collectivity and shape coexistence Analysis of ISOLDE Coulex experiments: GOSIA code GOSIA: most widely used code for low-energy Coulex T. Czosnyka et al., Bull. Am. Phys. Soc. 28 (1982) 745 http://www.slcj.uw.edu.pl/gosia Strong involvement of HIL Warsaw in Coulex data analysisof numerous ISOLDE experiments Shape coexistence 182-188Hg, 196-202Po, 188,190Pb Oblate shapes 140,142Sm Evolution of collectivity and shape coexistence 96,98Sr, 93-99Rb, 94,96Kr MINIBALL: 8 triple clusters 2+1 → 0+1 4+1 → 2+1 2+2 → 0+1 Kα (Hg) Kβ (Hg) 112Cd recoil (2+1 → 0+1) E2 matrix elements between yrast and non-yrast states up to 4+ quadrupole moments of the 2+ states shape parameters of the low-lying 0+ states degree of mixing between low-lying states 182Hg Bree et al., Phys. Rev. Lett. 112 (2014) 162701 K. Wrzosek-Lipska, M. Zielińska, P. Napiorkowski

GOSIA - semiclassical Coulomb excitation codes Developed and supported at Rochester, Warsaw, and Köln.

GOSIA Workshop, HIL, Warsaw 1st GOSIA Workshop 2008 - EURONS 2nd GOSIA Workshop 2013 - ENSAR 27 participants form 15 institutes 9 ISOLDE users Program 12 presentations: examples of COULEX analysis 3 working groups for hands-on session: practice with the GOSIA code dedicated session for ISOLDE users round-table discussion: users needs to GOSIA development.

Future: 182,184Hg cont. Future: 180,182Hf P-??? IS562

P-429 presented tomorrow M. Madurga, S. Paulauskas

Conversion electron spectroscopy Jarosław Perkowski University of Łódź

ULESE (University of Lodz an electron spectrometer )

Efficiency of the spectrometer

Electrons from 184Pt

TPC with optical readout Trigger Recording system p charge amplification e ionization electrons light HV electrodes counting gas at atmospheric pressure incoming identified ion gating electrode CCD PMT 6He 31Ar ?

Probing the neutron halo of 6He using the Warsaw Optical Time Projection Chamber (OTPC) Weak decay branch (10-6) 6He  a + d provides insight into the 2n halo of 6He Bunches of 6He ions were delivered by REX-Isolde and implanted into the OTPC Clear images of decay events with tracks of an a particle and a deuteron were recorded by a CCD camera Detailed analysis is in progress ISOLDE, August 2012 Anthony Raabe Preliminary!

b decay of 8He @ Dubna CCD Q = 4.3 MeV PMT Ea = 1150 keV Et = 2570 keV En = 610 keV We see about 400 triton events. The branching for the bt is 0.9 %

Thank you! The consortium Polska@ISOLDE is planning to apply to the Polish National Science Centre for funding our membership in ISOLDE. We hope to become a member again… Poland@