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T. Kawano
2 CoH 3 Code
2.1 Quick Glance
Each version of CoH 3 has a unique nickname taken from the moons of Uranus.
The current version of 3.5 Miranda consists of about 140 C++ source codes and 60
header files. The total line number is about 45,000. The code is written in a semiOOP (Object-Oriented Programming) style, and there are about 80 classes defined.
Unlike the other HF codes currently available in the market, such as EMPIRE [3] or
TALYS [4], CoH 3 includes its own optical model solver to generate the transmission
coefficients internally. This feature is the same as in the CCONE code [5].
Another noticeable difference is that CoH 3 runs both in the deterministic and
stochastic (Monte Carlo) modes [6]. In the Monte Carlo mode, the compound
nucleus decay is tracked by a random sampling technique in order to preserve
all correlated information. Albeit this feature is not yet widely used in practical
calculations for now, an accurate estimate of the exclusive particle emission spectra
can be examined.
CoH 3 is designed to calculate nuclear reactions at relatively low energies.
Although it is capable of calculating a 100-MeV nucleon induced reaction, it is
not so efficient. We will revisit this issue later.
2.2 Models and Modules
Spherical and Deformed Optical Models In the deformed nucleus case, a
rotational or vibrational model is employed for the coupled-channels (CC) calculation. These models yield a channel transmission coefficient T a , which defines
the probability of forming a compound nucleus from a channel a. The optical
model scattering wavefunction is also used in the DWBA (Distorted Wave Born
Approximation) method for the direct inelastic scattering process.
Compound Reaction Properties of excited states in a compound nucleus are determined by reading the nuclear structure database [7]. At higher excitation energies,
we use the Gilbert–Cameron level density formula [8] with updated parameters [9].
CoH 3 allows to overlap the discrete level and continuum regions, and some of the
levels can be embedded in the continuum. This is particularly important when some
γ transitions from highly excited states are observed experimentally. This often
impacts the isomeric state production.
The width fluctuation correction is calculated by applying the method of
Moldauer [10] with LANL updated parameters [11], which gives very similar
correction factors to the GOE (Gaussian Orthogonal Ensemble) results [12]. When
strongly coupled channels exist, the inelastic scattering process is calculated with
T. Kawano
2 CoH 3 Code
2.1 Quick Glance
Each version of CoH 3 has a unique nickname taken from the moons of Uranus.
The current version of 3.5 Miranda consists of about 140 C++ source codes and 60
header files. The total line number is about 45,000. The code is written in a semiOOP (Object-Oriented Programming) style, and there are about 80 classes defined.
Unlike the other HF codes currently available in the market, such as EMPIRE [3] or
TALYS [4], CoH 3 includes its own optical model solver to generate the transmission
coefficients internally. This feature is the same as in the CCONE code [5].
Another noticeable difference is that CoH 3 runs both in the deterministic and
stochastic (Monte Carlo) modes [6]. In the Monte Carlo mode, the compound
nucleus decay is tracked by a random sampling technique in order to preserve
all correlated information. Albeit this feature is not yet widely used in practical
calculations for now, an accurate estimate of the exclusive particle emission spectra
can be examined.
CoH 3 is designed to calculate nuclear reactions at relatively low energies.
Although it is capable of calculating a 100-MeV nucleon induced reaction, it is
not so efficient. We will revisit this issue later.
2.2 Models and Modules
Spherical and Deformed Optical Models In the deformed nucleus case, a
rotational or vibrational model is employed for the coupled-channels (CC) calculation. These models yield a channel transmission coefficient T a , which defines
the probability of forming a compound nucleus from a channel a. The optical
model scattering wavefunction is also used in the DWBA (Distorted Wave Born
Approximation) method for the direct inelastic scattering process.
Compound Reaction Properties of excited states in a compound nucleus are determined by reading the nuclear structure database [7]. At higher excitation energies,
we use the Gilbert–Cameron level density formula [8] with updated parameters [9].
CoH 3 allows to overlap the discrete level and continuum regions, and some of the
levels can be embedded in the continuum. This is particularly important when some
γ transitions from highly excited states are observed experimentally. This often
impacts the isomeric state production.
The width fluctuation correction is calculated by applying the method of
Moldauer [10] with LANL updated parameters [11], which gives very similar
correction factors to the GOE (Gaussian Orthogonal Ensemble) results [12]. When
strongly coupled channels exist, the inelastic scattering process is calculated with