TABLE X: Measured (n, γ ) cross sections of $^{156}$Dy and total uncertainties. Sample 〈 σ$_{exp}$ 〉 [mbarn] E$_{γ}$ = 326 keV dy-1 1669 ± 121 dy-2 1638 ± 114 dy-3 1619 ± 114 Weighted average 1641 ± 117 F. Isomeric ratios VI. MAXWELLIAN AVERAGED CROSS SECTIONS A. General remarks Isomeric ratios R$_{iso}$ = 〈 σ$_{exp}$ 〉 m σ$_{exp}$ tot (6) Φ = dN/dE$_{n}$ ∼ √ E$_{n}$ · e − E$_{n}$$^{/kT}$. (7) C. Calculation of Maxwellian average cross sections B. Evaluated cross sections from data libraries Isotope JEFF 3.0A JEFF 3.1 JENDL 3.3 ENDF-B/VII.0 $^{102}$Pd 397 397 250 820 $^{120}$Te – – – – $^{130}$Ba 2030 2530 2530 2800 $^{132}$Ba – – – 130 $^{156}$Dy 101.3 – – 91 TABLE XI: Upper limits (in eV) of the resolved resonance region in different databases. Cases without resonance infor- mation are indicated by empty entries. The libraries used were the ”Joint Evaluated Fis- sion and Fusion General Purpose File” ( JEFF 3.0A and JEFF 3.1 , www.nea.fr/html/dbdata/ JEFF/ ), the ”Japanese Evaluated Nuclear Data Library” ( JENDL 3.3 [38], wwwndc.tokai-sc.jaea.go.jp/jendl/), and the ”Evaluated Nuclear Data File” ( ENDF-B/VII.0 [39], www.nndc.bnl.gov/), which are partially based on experimental resonance parameters. For the investigated cases, the most recent data for σ (E$_{n}$) are provided by ENDF-B/VII.0 , which makes use of resonance parameters from the latest evaluation [36]. The differences between the four data libraries with respect to the resolved resonance region (RRR) are sum- marized in Table XI. Table XII shows that the contribu- tions of the RRR to the respective Maxwellian averaged cross sections for kT =5-100 keV are almost negligible, ex- cept for the lower temperatures in $^{130}$Ba, where the RRR reaches up to about 3 keV. In all libraries, the ( n, γ ) cross sections in the unresolved resonance region (URR) were obtained by Hauser-Feshbach (HF) calculations. Since this region contributes the most important part to the extrapolation towards the higher temperatures of the p - process, it is discussed in more detail. The Hauser-Feshbach calculations in the JENDL-3.3 evaluations were performed with the statistical model code CASTHY [40] for the isotopes investigated in this work. More specifically, the γ -ray strength function for $^{132}$Ba was adjusted to reproduce the available experi- mental capture cross section of Ref. [41]. For JEFF- 3.0A, the HF calculations are not documented, and in JEFF-3.1 an unspecified HF prediction with a Moldauer potential was used for $^{102}$Pd and $^{120}$Te, whereas the CASTHY code was also used for the URR of 130 , $^{132}$Ba. In ENDF/B-VII.0, the URR in $^{102}$Pd was obtained with the GNASH code [42], and for $^{156}$Dy results from EM- PIRE [43] were used. For $^{120}$Te and 130 , $^{132}$Ba the re- spective URR cross sections from JENDL-3.3 have been adopted also in ENDF/B-VII.0. The corrections for the spectrum differences as well as the extrapolations of the MACS to lower and higher values of kT were determined with the evaluated energy- dependent cross sections, σ (E$_{n}$), from the data libraries provided by the online database JANIS 3.0 (”Java-based Nuclear Information Software”, www.nea.fr/janis/) [37]. In a first step, the evaluated cross sections were folded with the experimental neutron spectrum. The ratios of the measured cross sections and the corresponding aver- The experimental neutron spectrum of the $^{7}$Li( p, n ) $^{7}$Be reaction simulates the energy dependence of the flux v · Φ ∼ E$_{n}$ · e − E$_{n}$/kT with kT =25.0 ± 0.5 keV almost perfectly [21]. However, the cutoff at E$_{n}$ = 106 keV and small deviations from the shape of the ideal Maxwellian spectrum require a correction of the measured cross sec- tion 〈 σ$_{exp}$ 〉 for obtaining a true Maxwellian average, 〈 σ 〉 25 keV . This correction is determined by means of the energy-dependent cross sections from data libraries. In an astrophysical environment with temperature T , interacting particles are quickly thermalized by collisions in the stellar plasma, and the neutron energy distribution can be described by a Maxwell-Boltzmann spectrum: were calculated for $^{121}$Te and $^{133}$Ba from the measured partial and total (n, γ ) cross sections. The present results at kT =25 keV are 0.126 ± 0.012 and 0.090 ± 0.009, respec- tively. These results are compatible with the thermal values at kT = 25 meV, which are 0.145 ± 0.026 for $^{121}$Te and 0.071 for $^{133}$Ba [35, 36]. 8