Comparing TWOFNR and FRESCO calculations for 56Ni transfer cross sections

(p,d) Zero-range and finite-range options Consistency with increasing beam energy Consistency with different potentials

(d,3He) Discontinuity with increasing energy in TWOFNR calculations

with Daehnick deuteron potential [for (d,3He) reaction only]

56Ni(p,d)

Same set of options• brush front end –

produces input file for both calculations

• did NOT include non-locality• not an option

for FRESCO• tried both ZR and FR

(LEA) options

Near peak, very little difference between the calculations

56Ni(p,d) cross sections – Zero-range and Finite-rangeChapel Hill 89 optical potential for pJohnson-Soper Adiabatic potential for d 7 Nov

Solid = TWOFNRDashed = FRESCO

15 Nov

56Ni(p,d) cross sections – increasing beam energyChapel Hill 89 optical potential for pJohnson-Soper Adiabatic potential + CH89 for d

Each color is a different beam energy (MeV/u)Solid = TWOFNRDashed = FRESCO

Little difference at peak with adiabatic pot.

Differences at: • larger angles • higher energy

15 Nov

56Ni(p,d) cross sections – different deuteron potentialChapel Hill 89 optical potential for pDaehnick Global optical potential for d

Each color is a different beam energy (MeV/u)Solid = TWOFNRDashed = FRESCO

Excellent agreement throughout the energy range using Daehnick deuteron potential

Shape of cross section is much different than when using adiabatic potential

56Ni(d,3He)

15 Nov

56Ni(d,3He) cross sections – increasing energy for (d,3He)Daehnick Global optical potential for dBechetti-Greenlees optical potential for 3He

Each color is a different beam energy (MeV/u)Solid = TWOFNRDashed = FRESCO

Little difference at low E (red, black, green)

Enormous differences above ~60 MeV/u

Related to Daehnick discontinuity ? [see later slides]

23 Nov

56Ni(d,3He) cross sections – different deuteron potential Perey-Perey optical potential for dBechetti-Greenlees optical potential for 3He

Each color is a different beam energy (MeV/u)Solid = TWOFNRDashed = FRESCO

Excellent agreement throughout the energy range with Perey-Perey deuteron potential

56Ni(d,3He)Daehnick discontinuity

56Ni(d,3He) cross sections – Daehnick discontinuity Daehnick Global optical potential for dBechetti-Greenlees optical potential for 3He 17 Nov

TWOFNR Smooth change in cross

section with energy E<75 and E>76,

Discontinuity at E~75.85 MeV

Thick black lines are 60, 70, 80 MeV/uThin lines are 1 MeV/u steps

56Ni(d,3He) cross sections – no Daehnick discontinuity Daehnick Global optical potential for dBechetti-Greenlees optical potential for 3He 17 Nov

FRESCOSmooth change in cross

section with energy over entire range

Thick black lines are 60, 70, 80 MeV/uThin lines are 1 MeV/u steps

Future investigations with these codes

(p,d) Compare FRESCO calculations with exact finite range option

(rather than LEA) – this is something TWOFNR doesn’t include Run calcs with JLM potential for proton

(d,3He) Try to determine if Daehnick discontinuity in TWOFNR related

to integration range, or possibly some other numerical effect Implement GDP08 potential in TWOFNR?