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Nuclear deexcitation lines are regularly observed in the $\ensuremath{\gamma}$-ray emission spectra of strong solar flares. The most prominent lines are produced by interactions of protons and $\ensuremath{\alpha}$ particles, accelerated up to hundreds of MeV, with abundant nuclei of the solar atmosphere. Analysis and interpretation of these lines, which carry valuable information on the solar flare properties, need cross-section data for the $\ensuremath{\gamma}$-ray line emission in these interactions for a wide particle energy range. To this purpose, we measured the $\ensuremath{\gamma}$-ray emission in interactions of $\ensuremath{\alpha}$-particle beams of ${E}_{\ensuremath{\alpha}}=50\text{--}90$ MeV with target foils of C, Mg, Si, and Fe at the center for proton therapy of the Helmholtz-Zentrum Berlin. Setups of three high-purity Ge detectors and one $\mathrm{La}{\mathrm{Br}}_{3}$:Ce detector have been employed to detect the $\ensuremath{\gamma}$ rays in two experiment campaigns. Relatively large distances of the detectors from the target and pulsed beams with sub-ns-wide pulses allowed the separation of beam-induced prompt $\ensuremath{\gamma}$-ray emission from the targets from other $\ensuremath{\gamma}$ rays and neutron-induced background. $\ensuremath{\gamma}$-ray production cross sections for about 60 deexcitation lines from excited target nuclei or reaction products have been determined. For the strongest deexcitation lines from the major target isotopes, $^{12}\mathrm{C}$, $^{24}\mathrm{Mg}$, $^{28}\mathrm{Si}$, $^{56}\mathrm{Fe}$, there are now measured cross-section data from reaction threshold to ${E}_{\ensuremath{\alpha}}=90$ MeV that can be directly used for astrophysical applications like solar flares. Comparison of the results with a cross-section compilation for strong $\ensuremath{\gamma}$-ray lines in solar flare emissions and the predictions of the talys nuclear reaction code were done. They underline the importance of cross-section determinations at accelerator laboratories for the establishment of an accurate cross-section data base in a wide projectile energy range.

Background: Neutron-rich nuclei in the $\mathrm{A}\ensuremath{\approx}140--160$ mass region provide valuable information on nuclear structure such as quadrupole- and octupole-shape coexistence and the evolution of the collectivity. These nuclei have also a nuclear engineering interest because they contribute to the total decay heat after a fission burst. The information concerning $^{145}\mathrm{La}$ is very limited.Purpose: The study of low-spin states in $^{145}\mathrm{La}$ will provide a more detailed level scheme and enable the determination of the half-lives of the excited states.Methods: Low-spin excited states in $^{145}\mathrm{La}$ have been investigated from the $^{145}\mathrm{Ba}\phantom{\rule{4pt}{0ex}}{\ensuremath{\beta}}^{\ensuremath{-}}$ decay. The $^{145}\mathrm{Ba}$ nuclei were directly produced by photofission in the ALTO facility or obtained from the ${\ensuremath{\beta}}^{\ensuremath{-}}$ decay of $^{145}\mathrm{Cs}$ also produced by photofission. Gamma spectroscopy and fast-timing techniques were used.Results: A new level scheme was proposed including 67 excited levels up to about 3 MeV and 164 transitions. Half-lives in the few-nanosecond range were measured for the first excited states. Configurations for levels up to $\ensuremath{\approx}600$ keV were discussed.Conclusions: The available information on the low-spin states of $^{145}\mathrm{La}$ has been modified and considerably extended. The analysis of the properties of the first excited states, such as excitation energies, decay modes, log $\mathit{\text{ft}}$ values, reduced transition probabilities, and Weisskopf hindrance factors, has enabled the identification of the first members of the bands corresponding to the ${g}_{7/2},$ ${d}_{5/2},$ and ${h}_{11/2}$ proton configurations.

Gamma-ray production cross section excitation functions have been measured for $30$, $42$, $54$ and $66$ MeV proton beams accelerated onto targets of astrophysical interest, $^{nat}$C, C + O (Mylar), $^{nat}$Mg, $^{nat}$Si and $^{56}$Fe, at the Sector Separated Cyclotron (SSC) of iThemba LABS (near Cape Town, South Africa). The AFRODITE array equipped with 8 Compton suppressed HPGe clover detectors was used to record $\gamma$-ray data. For known, intense $\gamma$-ray lines the previously reported experimental data measured up to $E_{p}\simeq$ $25$ MeV at the Washington and Orsay tandem accelerators were extended to higher proton energies. Our experimental data for the last 3 targets are reported here and discussed with respect to previous data and the Murphy \textit{et al.} compilation [ApJS 183, 142 (2009)], as well as to predictions of the nuclear reaction code TALYS. The overall agreement between theory and experiment obtained in first-approach calculations using default input parameters of TALYS has been appreciably improved by using modified optical model potential (OMP), deformation, and level density parameters. The OMP parameters have been extracted from theoretical fits to available experimental elastic/inelastic nucleon scattering angular distribution data by means of the coupled-channels reaction code OPTMAN. Experimental data for several new $\gamma$-ray lines are also reported and discussed. The astrophysical implications of our results are emphasised.

Inelastic ${}^{6}$Li scattering at 100 MeV/u on ${}^{12}$C and ${}^{93}$Nb have been measured with the high-resolution magnetic spectrometer Grand Raiden. The magnetic-rigidity settings of the spectrometer covered excitation energies from 10 to 40 MeV and scattering angles in the range $0^\circ < \theta_{\text{lab.}}< 2^\circ$. The isoscalar giant monopole resonance was selectively excited in the present data. Measurements free of instrumental background and the very favorable resonance-to-continuum ratio of ${}^{6}$Li scattering allowed for precise determination of the $E0$ strengths in ${}^{12}$C and ${}^{93}$Nb. It was found that the monopole strength in ${}^{12}$C exhausts $52 \pm 3^\text{(stat.)} \pm 8 ^\text{(sys.)}$\% of the energy-weighted sum rule (EWSR), which is considerably higher than results from previous $\alpha$-scattering experiments. The monopole strength in ${}^{93}$Nb exhausts $92 \pm 4^\text{(stat.)} \pm 10 ^\text{(sys.)}$\% of the EWSR, and it is consistent with measurements of nuclei with mass number of $A\approx90$. Such comparison indicates that the isoscalar giant monopole resonance distributions in these nuclei are very similar, and no influence due to nuclear structure was observed.

The high-spin states of the neutron-rich Ga81, with three valence protons outside a Ni78 core, were measured. The measurement involved prompt γ-ray spectroscopy of fission fragments isotopically identified using the combination of the variable mode spectrometer (VAMOS++) and the advanced gamma tracking array (AGATA). The new γ-ray transitions, observed in coincidence with Ga81 ions, and the corresponding level scheme do not confirm the high-spin levels reported earlier. The newly observed high-spin states in Ga81 are interpreted using the results of state-of-the-art large-scale shell model (LSSM) calculations. The lower excitation energy levels are understood as resulting from the recoupling of three valence protons to the closed doubly magic core, while the highest excitation energy levels correspond to excitations of the magic N=50 neutron core. These results support the doubly magic character of Ni78 and the persistence of the N=50 shell closure but also highlight the presence of strong proton-neutron correlations associated with the promotion of neutrons across the magic N=50 shell gap, only few nucleons away from Ni78.

The structure of low-lying excited states in $^{251}\mathrm{Fm}$, populated by the $\ensuremath{\alpha}$ decay of $^{255}\mathrm{No}$, has been investigated by means of combined $\ensuremath{\gamma}$ and internal conversion electron spectroscopy. The values for the internal conversion coefficients for the $1/{2}^{+}\ensuremath{\rightarrow}5/{2}^{+}$ and $5/{2}^{+}\ensuremath{\rightarrow}9/{2}^{\ensuremath{-}}$ transitions have been measured. The determined $M2/E3$ mixing ratio and lifetime for the $5/{2}^{+}$ decay to the ground state allowed to determine the corresponding reduced transitions strengths of $B(E3)=18(6)$ W.u. and $B(M2)=3.0(6)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}3}$ W.u. These results, as well as the results of previous studies in $N=151$ isotopes, are compared to theoretical calculations beyond the mean-field approach, including the first QRPA calculations using the Gogny D1M parametrization for such heavy odd-$N$ nuclei. The comparison points to the importance of accounting for the octupole vibrations for a proper understanding of the low-lying nuclear structure of some of the heaviest elements.

The structure of the S33 nucleus was investigated in the Mg24(N14,αp) fusion-evaporation reaction using a 40-MeV N14 beam. The level scheme was extended up to an excitation energy of 11.7 MeV and spin 19/2+. Lifetimes of the intermediate- and high-spin states have been investigated by the Doppler shift attenuation method. Data were compared with different shell-model calculations where effective interactions involving two main shells, the sd and the fp, are used.

Relatively neutron-rich thorium isotopes lie at the heart of a nuclear region of nuclei exhibiting octupole correlation effects. The detailed level structure of Th223 has been investigated in measurements of γ radiation following the fusion-evaporation channel of the Pb208(O18,3n)Th223 reaction at 85 MeV beam energy. The level structure has been extended up to spin 49/2, and 33 new γ rays have been added using triple-γ coincidence data. The spins and parities of the newly observed states have been confirmed by angular distribution ratios. In addition to the two known yrast bands based on a K=5/2 configuration, a non-yrast band has been established up to spin 35/2. We interpret this new structure as based on the same configuration as the yrast band in Th221 having dominant K=1/2 contribution. At the highest spin a backbending occurs around a rotational frequency of ℏω=0.23 MeV, very close to the one predicted in Th222, where a sharp transition to a reflection-symmetric shape is expected.

Valuable theoretical predictions of nuclear dipole excitations in the whole chart are of great interest for different nuclear applications, including in particular nuclear astrophysics. Here we extend our large-scale calculations of the $E1 \ensuremath{\gamma}$-ray strength function, obtained in the framework of the axially- symmetric-deformed quasiparticle random phase approximation (QRPA) based on the finite-range D1M Gogny force, to the calculation of the $M1$ strength function. We compare our QRPA prediction of the $M1$ strength with available experimental data and show that a relatively good agreement is obtained provided the strength is shifted globally by about 2 MeV and increased by an empirical factor of 2. Predictions of the $M1$ strength function for spherical and deformed nuclei within the valley of $\ensuremath{\beta}$ stability as well as in the neutron-rich region are discussed. Its impact on the radiative neutron capture cross section is also analyzed.

International audience; For the first time, using a unique finite-range interaction (D1M Gogny force), a fully coherent and time-feasible calculation of the Bohr Hamiltonian vibrational mass is envisioned in a Hartree-Fock-Bogoliubov + quasiparticle random-phase approximation (QRPA) framework. In order to reach a reasonable computation time, we evaluate the feasibility of this method by considering two restrictions for the QRPA: the Tamm-Dancoff approximation and the insertion of a valence space. We validate our approach in the even-even tin isotopes by comparing the convergence scheme of the mass parameter with those of built-in QRPA outputs: excited-state energy and reduced transition probability. The seeming convergence of these intrinsic quantities is shown to be misleading and the difference with the theoretical expected value is quantified. This work is a primary step towards the systematic calculation of mass parameters.

The ${}^{26}\mathrm{Al}$ radioisotope is of great importance for understanding the chemical and dynamical evolution of our galaxy. Among the possible stellar sources, massive stars are believed to be the main producer of this radioisotope. Understanding ${}^{26}\mathrm{Al}$ nucleosynthesis in massive stars requires estimates of the thermonuclear reaction rates of the $^{26}\mathrm{Al}$${(n,p)}^{26}$Mg, $^{26}\mathrm{Al}$${(n,\ensuremath{\alpha})}^{23}$Na, and $^{23}\mathrm{Na}$${(\ensuremath{\alpha},p)}^{26}$Mg reactions. These reaction rates depend on the spectroscopic properties of ${}^{27}\mathrm{Al}$ states above the neutron and alpha thresholds. In this context, the $^{27}\mathrm{Al}$${(p,{p}^{\ensuremath{'}})}^{27}$Al* reaction was studied at 18 MeV using a high-resolution Enge Split-Pole spectrometer. States from the ground state up to excitation energies of $\ensuremath{\approx}$14 MeV were populated. While up to the ${}^{23}\mathrm{Na}$ + $\ensuremath{\alpha}$ threshold no additional states are observed, we report for the first time 30 new levels above the ${}^{23}\mathrm{Na}$ + $\ensuremath{\alpha}$ threshold and more than 30 new states above the ${}^{26}\mathrm{Al}$ + n threshold for which excitation energies are determined with an uncertainty of 4--5 keV.

The nucleus 35S has been studied by in-beam ?-ray spectroscopy using the 24Mg(14N,3p) fusion-evaporation reaction at Elab=40 MeV. A level scheme extended up to J?=17/2+ at 8023 keV and J?=13/2- at 6352 keV has been established. Lifetimes of six excited states have been determined by applying the Doppler shift attenuation method. The experimental data have been compared with the results of large-scale shell model calculations performed using different effective interactions and model spaces allowing particle-hole excitations across the N=Z=20 shell gap. © 2014 American Physical Society.

Three superdeformed bands have been observed in ${}^{191}$Au using the EUROGAM II multidetector array. The previously known yrast superdeformed band has been extended up to very high rotational frequencies and two new excited bands have been assigned to this nucleus. These bands behave as signature partners and display characteristics which suggest they could be based either on the $\ensuremath{\pi}$ [532]3/2 orbital alone or on that orbital plus the $\ensuremath{\pi}$ [530]1/2 orbital, which become the $[\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{431}]$3/2,1/2 doublet in the pseudospin formalism.

The high-spin states of the two neutron-rich nuclei ${}^{88}$Kr${}_{52}$ and ${}^{89}$Rb${}_{52}$ have been studied from the ${}^{18}$O+${}^{208}$Pb fusion-fission reaction. Their level schemes were built from triple $\ensuremath{\gamma}$-ray coincidence data, and $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ angular correlations were analyzed in order to assign spin and parity values to most of the observed states. The two level schemes evolve from collective structures to single-particle excitations as a function of the excitation energy. Comparison with results of shell-model calculations gives the specific proton and neutron configurations which are involved to generate the angular momentum along the yrast lines.

Odd-odd ${}^{136}$Cs nuclei have been produced in the ${}^{18}\mathrm{O}+{}^{208}$Pb and ${}^{12}\mathrm{C}+{}^{238}$U fusion-fission reactions and their $\ensuremath{\gamma}$ rays studied with the Euroball array. The high-spin level scheme was built up to $\ensuremath{\sim}$4.7 MeV excitation energy and spin $I\ensuremath{\sim}16\ensuremath{\hbar}$ from the triple $\ensuremath{\gamma}$-ray coincidence data. The configurations of the three structures observed above $\ensuremath{\sim}$2 MeV excitation energy are first discussed by analogy with the proton excitations identified in the semimagic ${}^{137}$Cs${}_{82}$ nucleus, which involve the three high-$j$ orbits lying above the $Z=50$ gap, $\ensuremath{\pi}{g}_{7/2}$, $\ensuremath{\pi}{d}_{5/2}$, and $\ensuremath{\pi}{h}_{11/2}$. This is confirmed by the results of shell-model calculations performed in this work.

Excited states in the doubly-odd{sup 184}Au nucleus have been studied by in-beam {gamma}-ray spectroscopy. This nucleus was produced through the fusion-evaporation reactions {sup 165}Ho({sup 24}Mg, 5{ital n}), {sup 170}Yb({sup 19}F, 5{ital n}), and {sup 161}Dy({sup 27}Al, 4{ital n}). Different rotational band structures have been observed and interpreted as specific couplings of proton and neutron single-particle excitations present in neighboring odd Au and Pt nuclei. {copyright} {ital 1996 The American Physical Society.}

From the observed competition between $M1$ and $E2$ $\ensuremath{\gamma}$ transitions deexciting the states of the two signature partner yrast superdeformed bands in $^{193}\mathrm{Tl}$, the ${i}_{\frac{13}{2}}$ ($\ensuremath{\Omega}=\frac{5}{2}$) intruder proton orbital is found to have $\frac{({g}_{K}\ensuremath{-}{g}_{R})K}{{Q}_{0}}=0.138\ifmmode\pm\else\textpm\fi{}0.008$. A model dependent value of ${g}_{s}^{\mathrm{eff}}=(0.7\ifmmode\pm\else\textpm\fi{}0.2){g}_{s}^{\mathrm{free}}$ is deduced. A saturation of the ${\mathcal{T}}^{2}$ moments of inertia, at rotational frequency $\ensuremath{\hbar}\ensuremath{\omega}g0.32$ MeV, is observed for the two bands. This feature is discussed in terms of exhausted quasineutron alignment in the presence of substantially reduced quasiproton alignment due to Pauli blocking.

Five $N=82$ isotones have been produced in two fusion-fission reactions and their $\ensuremath{\gamma}$ rays studied with the Euroball array. The high-spin states of ${}^{139}$La have been identified, while the high-spin yrast and near-to-yrast structures of the four others have been greatly extended. From angular correlation analysis, spin values have been assigned to some states of ${}^{136}$Xe and ${}^{137}$Cs. Several cascades involving $\ensuremath{\gamma}$ rays of ${}^{139}$La have been found to be delayed; they deexcite an isomeric state with ${T}_{1/2}=315(35)$ ns located at 1800 keV excitation energy. The excited states of these five $N=82$ isotones are expected to be due to various proton excitations involving the three high-$j$ subshells located above the $Z=50$ shell closure. This is confirmed by the results of shell-model calculations performed in this work. In addition, high-spin states corresponding to the excitation of the neutron core have been unambiguously identified in ${}^{136}$Xe, ${}^{137}$Cs, and ${}^{138}$Ba.

The ${}^{119--126}$Sn nuclei have been produced as fission fragments in two reactions induced by heavy ions: ${}^{12}\text{C}+{}^{238}\text{U}$ at a bombarding energy of 90 MeV and ${}^{18}\text{O}+{}^{208}\text{Pb}$ at 85 MeV. Their level schemes have been built from $\ensuremath{\gamma}$ rays detected using the Euroball array. High-spin states located above the long-lived isomeric states of the even- and odd-$A$ ${}^{120--126}$Sn nuclei have been identified. Moreover, isomeric states lying around 4.5 MeV have been established in ${}^{120,122,124,126}$Sn from the delayed coincidences between the fission fragment detector SAPhIR and the Euroball array. The states located above 3 MeV excitation energy are ascribed to several broken pairs of neutrons occupying the $\ensuremath{\nu}{h}_{11/2}$ orbit. The maximum value of angular momentum available in such a high-$j$ shell, i.e., for midoccupation and the breaking of the three neutron pairs, has been identified. This process is observed for the first time in spherical nuclei.

The ${}^{83,81}\phantom{\rule{-0.16em}{0ex}}$As nuclei have been produced as fission fragments in the fusion reaction ${}^{18}$O + ${}^{208}$Pb at 85 MeV bombarding energy and studied with the Euroball array. Medium-spin states of ${}^{83,81}\phantom{\rule{-0.16em}{0ex}}$As have been established up to $\ensuremath{\sim}3.5$ MeV excitation energy. From angular correlation analysis, spin values have been assigned to most of the ${}^{81}\phantom{\rule{-0.16em}{0ex}}$As excited states. The behaviors of the yrast structures identified in this work are discussed in comparison with the general features known in the mass region. Then they are compared to the results of two theoretical approaches: the ``rotor + quasiparticle'' for ${}^{81}\phantom{\rule{-0.16em}{0ex}}$As and the shell model using the effective interactions JUN45 for ${}^{83,81}\phantom{\rule{-0.16em}{0ex}}\phantom{\rule{-0.16em}{0ex}}$As.

$\ensuremath{\gamma}$-ray production cross sections have been measured in proton irradiations of N, Ne, and Si and $\ensuremath{\alpha}$-particle irradiations of N and Ne. In the same experiment we extracted also line shapes for strong $\ensuremath{\gamma}$-ray lines of $^{16}\mathrm{O}$ produced in proton and $\ensuremath{\alpha}$-particle irradiations of O. For the measurements gas targets were used for N, O, and Ne and a thick foil for Si. All targets were of natural isotopic composition. Beams in the energy range up to 26 MeV for protons and 39 MeV for $\ensuremath{\alpha}$ particles were delivered by the Institut de Physique Nucl\'eaire--Orsay tandem accelerator. The $\ensuremath{\gamma}$ rays were detected with four high-purity Ge detectors in the angular range ${30}^{\ifmmode^\circ\else\textdegree\fi{}}$ to ${135}^{\ifmmode^\circ\else\textdegree\fi{}}$. We extracted 36 cross-section excitation functions for proton reactions and 14 for $\ensuremath{\alpha}$-particle reactions. For the majority of the excitation functions no other data exist to our knowledge. Where comparison with existing data was possible, usually a very good agreement was found. It is shown that these data are very interesting for constraining nuclear reaction models. In particular, the agreement of cross section calculations in the nuclear reaction code talys with the measured data could be improved by adjusting the coupling schemes of collective levels in the target nuclei $^{14}\mathrm{N}$, $^{20,22}\mathrm{Ne}$, and $^{28}\mathrm{Si}$. The importance of these results for the modeling of nuclear $\ensuremath{\gamma}$-ray line emission in astrophysical sites is discussed.

A detailed {gamma}-ray spectroscopy of the lowest two negative-parity bands in {sup 156}Gd has been performed in the framework of the TetraNuc collaboration. Relative {gamma}-ray intensities of all transitions connecting these bands as well as the ones to the ground-state band are presented. Angular distribution analysis has been performed to determine the nature and the mixing ratio of one of the newly established transitions linking the two excited bands.

Two neutron-rich N=93 isotones, {sup 155}Sm and {sup 153}Nd, have been studied by delayed gamma-ray and conversion-electron spectroscopy at the Lohengrin mass spectrometer. A half-life of 2.9(5) mus has been measured for the nu5/2{sup +}[642] state at 16.5 keV in {sup 155}Sm. The decay of a 1.17(7)-mus isomer in {sup 153}Nd, at 191.7 keV, has been remeasured and its spin has been reassigned as (5/2){sup +}. This state contains a strong component of the nu5/2{sup +}[642] Nilsson orbital. In addition, a new 1.00(8)-mus isomeric state at 538.6 keV, with a probable nu11/2{sup -}[505] Nilsson configuration, has been observed in {sup 155}Sm. Triple gamma-ray coincidence data from the spontaneous fission of a {sup 252}Cf source placed inside the Gammasphere array were used to extend the collective band on top of the (5/2{sup +}) isomeric state of {sup 153}Nd, and a new band with the same bandhead spin has been observed in {sup 151}Ce. The observation of this new band and an additional new transition in the ground-state band has led us to change the ground-state spin of {sup 151}Ce to (3/2{sup -}). Calculations using the quasiparticle-rotor model successfully reproduce the majority of the features of the gamma decays of these nuclei,more » including branching ratios and isomeric half-lives. Because this model uses a reflection-symmetric core, we conclude that the polarizing effect of the odd particle is responsible for the dipole moment present in the nu5/2{sup +}[642] states of the three nuclei studied and the nu11/2{sup -}[505] level of {sup 155}Sm.« less

Three superdeformed (SD) bands including states with spins {ital I}{sup {pi}}{le}22{sup +} are predicted for {sup 192}Hg. The SD and normally deformed levels are calculated as eigenstates of the Griffin-Hill-Wheeler equation treated in the Gaussian overlap approximation. Potential and tensor of inertia are deduced from constrained Hartree-Fock-Bogoliubov calculations based on Gogny's force. Rates for {ital E}2 in-band transitions are deduced and compared with recent measurements. The decay out of SD bands is discussed.

The high-spin normally deformed and superdeformed states of ${}^{194}\mathrm{Hg}$ have been populated in an exit channel of the ${}^{16}{\mathrm{O}+}^{186}\mathrm{W}$ reaction at 110 MeV bombarding energy. The Doppler shift analysis of the energies of the \ensuremath{\gamma} transitions de-exciting both normally deformed and superdeformed states in ${}^{194}\mathrm{Hg}$ indicates a lower recoil velocity of the ${}^{194}\mathrm{Hg}$ nucleus compared to that of the ${}^{196}\mathrm{Pb}$ nucleus obtained from the $6n$ exit channel of the complete-fusion compound nucleus. This suggests that incomplete fusion plays the main role in the population of normally deformed and superdeformed states of ${}^{194}\mathrm{Hg}$ in this reaction.

A study of the Nd-136 nucleus has been performed with the EUROBALL III multidetector to establish the decay-out of the yrast superdeformed (SD) band. Three discrete linking transitions (754, 1456, and 1493 keV) have been discovered, establishing the position of the SD band at 7.03 MeV excitation energy with proposed spin and parity 17((-)) for the lowest observed SD state. Neutron pairing gap parameters for SD shapes have been extracted in Nd isotopes, using the strong-coupling model and odd-even mass difference formulas. The major conclusion of our phenomenological analysis is that the pairing correlations do subsist in the SD configurations of nuclei in the A = 130 mass region. [S0556-2813(99)01312-6].