GRETINA at ATLAS C.J. (Kim) Lister ATLAS Users Workshop 8-9 th October 2009 GRETINA ATLAS GAMMASPHERE

GRETINA at ATLAS C.J. (Kim) Lister Richmond Workshop on optimizing GRETINA Science th October 2007

GRETINA Science Opportunities, U. of Richmond VA, th Oct “Home Run Experiments” What are the GRETINA-and-ATLAS unique experiments that CANNOT be done with Gammasphere? Heavy Element Spectroscopy ~ 100 Sn “In-Beam” Coulomb Excitation of CARIBU Beams Inelastic Transfer with CARIBU (& stable) beams

GRETINA Science Opportunities, U. of Richmond VA, th Oct Our Nuclear Domain From: Yu. Ogenessian, DUBNA

GRETINA Science Opportunities, U. of Richmond VA, th Oct “Home Run Experiments” What are the GRETINA-and-ATLAS unique experiments that CANNOT be done with Gammasphere? Heavy Element Spectroscopy ~ 100 Sn “In-Beam” Coulomb Excitation of CARIBU Beams Inelastic Transfer with CARIBU (& stable) beams

GRETINA Science Opportunities, U. of Richmond VA, th Oct Sn Region “In-Beam” MUST have Mass Selection MUST have super-selective trigger. Advantages: Count rate, Compact geometry favors FMA trigger, Efficiency for high energy gamma rays, Excellent Doppler Correction.  Simulated single-  efficiency  10% at 1.0 MeV 5% at 4.0 MeV

GRETINA Science Opportunities, U. of Richmond VA, th Oct “Home Run Experiments” What are the GRETINA-and-ATLAS unique experiments that CANNOT be done with Gammasphere? Heavy Element Spectroscopy ~ 100 Sn “In-Beam” Coulomb Excitation of CARIBU Beams Inelastic Transfer with CARIBU (& stable) beams

GRETINA Science Opportunities, U. of Richmond VA, th Oct Coulomb Excitation of CARIBU Neutron Rich beams Two very exciting paths: CHICO Conventional Multi-Step Coulomb Excitation OR Unconventional “goundstate excitations only” E J

GRETINA Science Opportunities, U. of Richmond VA, th Oct

10 How much beam do we need with Gammasphere? 14h at pps! 1/25 1/250 1/ pps for 2 weeks 10 6 pps for 2 weeks 10 5 pps for 2 weeks To identify excited 2 + state (beyond the ) in vibrational nucleus (B(E2)~1Wu) with Gammasphere for 2 weeks beam time we need 10 5 pps. For complete spectroscopy pps will be needed!

GRETINA Science Opportunities, U. of Richmond VA, th Oct The Gretina Advantage This kind of experiment is a “singles” study. Rates will be low with CARIBU beams, so rate is not an issue. (Though probably needing an active beam detector) BUT Recoil velocity is well defined in direction, but large (~7%) Gammasphere does not Doppler correct well, as gamma angle is not well defined, so lines are many 10’s keV broad …. sharpening them back to ~5keV will be equivalent (in sensitivity) to 10 times more beam.

GRETINA Science Opportunities, U. of Richmond VA, th Oct “Home Run Experiments” What are the GRETINA-and-ATLAS unique experiments that CANNOT be done with Gammasphere? Heavy Element Spectroscopy ~ 100 Sn “In-Beam” Coulomb Excitation of CARIBU Beams Inelastic Transfer with CARIBU (& stable) beams

GRETINA Science Opportunities, U. of Richmond VA, th Oct Multinucleon transfer with thick and thin targets. Deep-inelastic products Fission products Deep-inelastic products Fission products

GRETINA Science Opportunities, U. of Richmond VA, th Oct Inelastic Transfer Is a dirty business….. Lots of exotic nuclei can be made by multi-neutron transfer....especially starting with CARIBU beam GRETINA counting at 50,000Hz is needed to improve on Gammasphere stable-beam transfer studies

GRETINA Science Opportunities, U. of Richmond VA, th Oct Gammasphere