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Lutetium-177 (177Lu) radioisotope has been suggested for radioimmunotherapy application in nuclear medicine. Presently 177Lu has been mostly produced using neutron activation in nuclear reactors, whereas cyclotron-based production has not been well explored. In this paper, we theoretically propose cyclotron-based deuteron beams for 177Lu production. By Employing the TALYS 2017 codes, we calculated nuclear cross-sections and the End-of-Bombardment (EOB) yields of 176Yb(d,n) 177Lu reaction for direct production of 177Lu as well as 176Yb(d,p)177Yb→177Lu reaction for indirect production of 177Lu. The TALYS calculated cross-sections indicated that the threshold energy of both investigated nuclear reactions is 0 MeV; thus 177Lu could be produced at low deuteron energy bombardment, though significant amount of 177Lu radioactivity could only be generated for deuteron beams with energy greater than 6 MeV. The calculated EOB yields for 176Yb(d,n)177Lu reaction and 176Yb(d,p)177Yb reaction were 0.519 and 181.1 MBq/μAh respectively, which well agreed with previous experimental results published elsewhere. In conclusion, both nuclear reactions are possible for 177Lu production though the indirect method via 176Yb(d,p)177Yb→177Lu reaction would give much better EOB yield than that of direct method.

The neutron-induced nuclear reaction data play an important role in the studies of the nuclear structure, the nuclear reaction mechanism and the nuclear energy applications. Particularly, the cross section data of the neutron-induced nuclear reactions are an indispensable component in the studies of the nuclear technology such as fusion devices, fission power plants, and accelerators. In the actual cross section measurements of the neutron-induced nuclear reactions with natural samples containing many stable isotopes, many nuclear reactions will take place at the same time and the mutual interference of various nuclear reactions is difficult to avoid. In this case, the standardization expressions of the neutron-induced nuclear reactions are particularly important. The expressions of the neutron-induced nuclear reactions in the relevant literatures are various and confusing, which is bad not only for the academic exchanges and the construction of nuclear reaction databases, but also for the basic research and the related application research of the nuclear physics. Some problems related to the expressions on the neutron-induced nuclear reactions were carefully combed and discussed, and the suggestions on the standardization expressions of the neutron-induced nuclear reactions (which were divided into the single nuclear reaction and the multiple nuclear reaction producing the same daughter nucleus. And the former was further divided into the daughter nucleus with metastable state and the daughter nucleus without metastable state, while the latter into the nuclear reaction that directly produces the same daughter nucleus and the nuclear reaction that directly and indirectly produces the same daughter nucleus) were given. The work is useful for the academic exchanges, the construction of the nuclear reaction databases, the basic researches and the related application researches of the nuclear physics.

TALYS is a software package for the simulation of nuclear reactions below 200 MeV. It is used worldwide for the analysis and prediction of nuclear reactions and is based on state-of-art nuclear structure and nuclear reaction models. A general overview of the implemented physics and capabilities of TALYS is given. The general nuclear reaction mechanisms described are the optical model, direct reactions, compound nucleus model, pre-equilibrium reactions and fission. The most important nuclear structure models are those for masses, discrete levels, level densities, photon strength functions and fission barriers. A wide variety of nuclear reactions simulated with TALYS will be demonstrated, ranging from low-energy neutron cross sections, astrophysics, high-energy charged particle reactions and other reactions. TALYS is a nuclear reaction software which aims to give a complete description of nuclear reaction observables, and to be an important link between fundamental nuclear physics and applications.

We present a determination of the parton distribution functions of the proton in which NLO and NNLO fixed-order calculations are supplemented by NLLx small-x resummation. Deep-inelastic structure functions are computed consistently at NLO+NLLx or NNLO+NLLx, while for hadronic processes small-x resummation is included only in the PDF evolution, with kinematic cuts introduced to ensure the fitted data lie in a region where the fixed-order calculation of the hard cross-sections is reliable. In all other respects, the fits use the same methodology and are based on the same global dataset as the recent NNPDF3.1 analysis. We demonstrate that the inclusion of small-x resummation leads to a quantitative improvement in the perturbative description of the HERA inclusive and charm-production reduced cross-sections in the small x region. The impact of the resummation in our fits is greater at NNLO than at NLO, because fixed-order calculations have a perturbative instability at small x due to large logarithms that can be cured by resummation. We explore the phenomenological implications of PDF sets with small-x resummation for the longitudinal structure function FL at HERA, for parton luminosities and LHC benchmark cross-sections, for ultra-high-energy neutrino–nucleus cross-sections, and for future high-energy lepton–proton colliders such as the LHeC.

We propose an extension of the inclusive breakup model of Ichimura, Austern and Vincent [Phys. Rev. C 32, 431 (1985)] for the evaluation of incomplete fusion (ICF) cross sections in nuclear reactions induced by two-body projectiles. The main idea, adopted in other methods, consists in the separation of the participant-target optical potential into its direct reaction and compound reaction components, the latter being responsible for the ICF contribution of the total nonelastic breakup cross section. Preliminary comparison with experimental data shows encouraging results.

Pinpointing the role of geometric phaseDuring chemical reactions, electrons usually rearrange more quickly than nuclei. Thus, theorists often adopt an adiabatic framework that considers vibrational and rotational dynamics within single electronic states. Near the regime where two electronic states intersect, the dynamics get more complicated, and a geometric phase factor is introduced to maintain the simplifying power of the adiabatic treatment. Yuan et al. conducted precise experimental measurements that validate this approach. They studied the elementary H + HD reaction at energies just above the intersection of electronic states and observed angular oscillations in the product-state cross sections that are well reproduced by simulations that include the geometric phase.Science, this issue p. 1289Theory has established the importance of geometric phase (GP) effects in the adiabatic dynamics of molecular systems with a conical intersection connecting the ground- and excited-state potential energy surfaces, but direct observation of their manifestation in chemical reactions remains a major challenge. Here, we report a high-resolution crossed molecular beams study of the H + HD → H2 + D reaction at a collision energy slightly above the conical intersection. Velocity map ion imaging revealed fast angular oscillations in product quantum state–resolved differential cross sections in the forward scattering direction for H2 products at specific rovibrational levels. The experimental results agree with adiabatic quantum dynamical calculations only when the GP effect is included.

Subjecting a physical system to extreme conditions is one of the means often used to obtain a better understanding and deeper insight into its organization and structure. In the case of the atomic nucleus, one such approach is to investigate isotopes that have very different neutron-to-proton ( N / Z ) ratios than in stable nuclei. Light, neutron-rich isotopes exhibit the most asymmetric N / Z ratios and those lying beyond the limits of binding, which undergo spontaneous neutron emission and exist only as very short-lived resonances (about 10 −21  s), provide the most stringent tests of modern nuclear-structure theories. Here we report on the first observation of 28 O and 27 O through their decay into 24 O and four and three neutrons, respectively. The 28 O nucleus is of particular interest as, with the Z  = 8 and N  = 20 magic numbers 1 , 2 , it is expected in the standard shell-model picture of nuclear structure to be one of a relatively small number of so-called ‘doubly magic’ nuclei. Both 27 O and 28 O were found to exist as narrow, low-lying resonances and their decay energies are compared here to the results of sophisticated theoretical modelling, including a large-scale shell-model calculation and a newly developed statistical approach. In both cases, the underlying nuclear interactions were derived from effective field theories of quantum chromodynamics. Finally, it is shown that the cross-section for the production of 28 O from a 29 F beam is consistent with it not exhibiting a closed N  = 20 shell structure. Observation of 28 O and 27 O through their decay into 24 O and four and three neutrons, respectively, is reported, with the 28 O nucleus being of particular interest owing to proton and neutron magic numbers and its extremely asymmetric neutron-to-proton ratio.

We present an improved determination of the strange quark and antiquark parton distribution functions of the proton by means of a global QCD analysis that takes into account a comprehensive set of strangeness-sensitive measurements: charm-tagged cross sections for fixed-target neutrino–nucleus deep-inelastic scattering, and cross sections for inclusive gauge-boson production and W -boson production in association with light jets or charm quarks at hadron colliders. Our analysis is accurate to next-to-next-to-leading order in perturbative QCD where available, and specifically includes charm-quark mass corrections to neutrino–nucleus structure functions. We find that a good overall description of the input dataset can be achieved and that a strangeness moderately suppressed in comparison to the rest of the light sea quarks is strongly favored by the global analysis.

The triangular lattice antiferromagnet (TLAF) has been the standard paradigm of frustrated magnetism for several decades. The most common magnetic ordering in insulating TLAFs is the 120° structure. However, a new triple- Q chiral ordering can emerge in metallic TLAFs, representing the short wavelength limit of magnetic skyrmion crystals. We report the metallic TLAF Co 1/3 TaS 2 as the first example of tetrahedral triple- Q magnetic ordering with the associated topological Hall effect (non-zero σ xy ( H  = 0)). We also present a theoretical framework that describes the emergence of this magnetic ground state, which is further supported by the electronic structure measured by angle-resolved photoemission spectroscopy. Additionally, our measurements of the inelastic neutron scattering cross section are consistent with the calculated dynamical structure factor of the tetrahedral triple- Q state. Skyrmion crystals, where skyrmions are arranged close packed in a triangular lattice arise due to the superposition of three magnetic spin spirals, each with a distinct wave vector, Q. Such skrymion crystals have been found in a diverse array of materials. Here, Park et al find a short wavelength (or dense skyrmion) limit of this skyrmion crystal structure in Co1/3TaS2, a metallic triangular lattice antiferromagnet, in the form of a triple Q magnetic ordering, with four magnetic sublattices.’

Magnetic molecules, modelled as finite-size spin systems, are test-beds for quantum phenomena1 and could constitute key elements in future spintronics devices2–5, long-lasting nanoscale memories6 or noise-resilient quantum computing platforms7–10. Inelastic neutron scattering is the technique of choice to probe them, characterizing molecular eigenstates on atomic scales11–14. However, although large magnetic molecules can be controllably synthesized15–18, simulating their dynamics and interpreting spectroscopic measurements is challenging because of the exponential scaling of the required resources on a classical computer. Here, we show that quantum computers19–22 have the potential to efficiently extract dynamical correlations and the associated magnetic neutron cross-section by simulating prototypical spin systems on a quantum hardware22. We identify the main gate errors and show the potential scalability of our approach. The synergy between developments in neutron scattering and quantum processors will help design spin clusters for future applications.Inelastic neutron scattering is used to probe the spin dynamics of molecular nanomagnets, but extensive supporting computations make the technique challenging. Proof-of-principle experiments now show that quantum computers may solve these computations efficiently.