arXiv subjects

Ken'ichi Nomoto

Publications and source records attributed to Ken'ichi Nomoto.

At least 19 recordsLinked to original sources

arXiv2026

Nucleosynthesis of Pop III and Fe-enriched Pop II Pair-Instability Supernovae

Recently discovered very metal-poor (VMP) star LAMOST J1010+2358 shows a peculiar abundance pattern that is remarkably well fit by a Pop III pair-instability supernova (PISN) of $\simeq 260$ M$_\odot$. Motivated by this, we investigate the nucleosynthetic characteristics of Pop III and Pop II PISNe to provide theoretical constraints for future observations. This paper is divided into two parts. First, we explore the evolution and nucleosynthesis of Pop III PISNe with initial masses of 130 - 300 M$_\odot$. Our main aim is to investigate how the uncertainty in $^{12}$C$(α,γ)^{16}$O and $^{16}$O+$^{16}$O reaction rates affect their explosion properties and nucleosynthesis. We find that the yields of odd-$Z$ elements are particularly sensitive to the $^{12}$C$(α,γ)^{16}$O rate, while the production of Fe-peak elements shows significant sensitivity to both rates. Second, we investigate the nucleosynthetic features of Pop II PISNe formed in gas enriched exclusively by Pop III PISN ejecta. By employing a time-dependent convection model during the explosion, we demonstrate that metal enrichment increases opacity and triggers vigorous convective mixing. This hydrodynamic effect significantly enhances the explosion energy and $^{56}\text{Ni}$ production. Consequently, Pop II PISNe exhibit distinct chemical signatures, including a weaker odd-even effect and enhanced Zn-Ge production, providing unique diagnostics for identifying PISN remnants in the early Universe.

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arXiv2026

Chemical Abundance Ratios of Nitrogen Rich Galaxies Identified at $z\sim 6-12$: Observational Demographics and Models

We present chemical abundance ratios of 8 nitrogen-rich ([N/O]$>0.3$) galaxies at $z\sim 6-12$ identified by the first 4 years of the JWST observations, and compare these ratios with chemical evolution models. We reanalyze the JWST/NIRSpec data of these galaxies in the self-consistent manner for line fluxes and upper limits including those previously unconstrained. We derive the abundance ratios and constraints of [N/O], [C/O], [Ne/O], [Ne/C], [Ar/O], [S/O] and [Fe/O], characterizing the nebulae in the galaxies with the electron temperatures and densities measured with {\sc[Oiii]}$\lambda4363$ and {\sc[Oii]}$λ\lambda3727, 3729$ lines, respectively. We develop the chemical evolution models for the three major scenarios, Wolf-Rayet stars, supermassive stars, and tidal disruption events (TDEs) with the AGB star contribution, integrating the ejecta of the stars and core-collapse supernovae (CCSNe) over the age with yields calculated by numerical simulations. We compare the models with the [N/O] measurements and stellar ages, and find that all of the scenarios reproduce [N/O] as high as those of our galaxies. However, the time-scales of the high [N/O] ratios are too short to explain our galaxies in any of the scenarios, suggestive of very frequent failed supernovae that do not increase oxygen against nitrogen. We find that the three scenarios are distinguished in the plane of [Ne/C] vs. [N/O] due to Ne production outside CNO cycle, and that the observed abundance ratios are explained by the Wolf-Rayet models better than supermassive-star and TDE models. We argue that abundance ratios of various elements and time scales are clues for understanding nitrogen-rich galaxies.

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arXiv2026

Primordial Black Hole Triggered Type Ia Supernovae II: Comparison with Supernova Remnants and Galactic Chemical Evolution

The asteroid-mass class of Primordial Black Holes (PBHs) is one of the candidates for the dark matter in the universe. With a mass between $4 \times 10^{-17} < M_{\rm PBH} < 4 \times 10^{-12}~M_{\odot}$, they could be the major component of dark matter in the cosmic mass budget. The infall of these PBH into a white dwarf could be one triggering mechanism of Type Ia supernovae (SNe Ia). In [Leung et al, ApJ 991, 11 (2025)] (Paper I), we studied the ignition, explosion dynamics, radiative transfer, and post-explosion nucleosynthesis of the PBH-triggered SNe Ia. The diversity of the explosion models can reconcile with the empirical Phillips relation. In this work, we developed the PBH-triggered SN Ia models in various metallicity. We show that models from this channel can explain some recently observed SN Ia light curves and supernova remnants. We further investigate how these supernovae could affect the chemical evolution on the galactic scale by adding the new SN Ia models as a new chemical source. We examine how the observed chemical trends of stars can lead to constraints on the fraction of this explosion channel relative to the canonical binary star channel. Our models suggest that the PBH can be one major SN Ia channel in the early universe. We also include a comparative study to extract the effects of PBH-triggered SN Ia parameters on the actual chemical trends in the galactic chemical evolution model.

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arXiv2026

Revisiting the Perseus Cluster II: Metallicity-Dependence of Massive Stars and Chemical Enrichment History

The legacy Hitomi telescope has delivered the precise measurements of the chemical abundances in the Perseus Cluster, covering the Si-group (Si, S, Ar, Ca) and Fe-group elements (Cr, Mn, Ni). In Paper I (Leung et al., ApJ 2025), we examined the role of convection parameters and presented new core-collapse supernova (CCSN) explosion models at solar metallicity, which fit the observed abundance pattern. In this article, we extend our calculation for the stellar evolutionary models and CCSN models of the initial mass $15 - 60M_{\odot}$ and the metallicity $Z = 0 - Z_{\odot}$. The detailed pre- and post-explosion chemical profiles are calculated with a large post-processing network to capture the production of $α$-chain elements (e.g., Si, S, Ar), odd-number elements (e.g., P, K, Cl), and iron-group elements (e.g., Mn, Ni). We study the role of CCSNe in the production of these elements. We compare the galactic chemical evolution model based on the nucleosynthesis yield of the new massive stars and other yield tables from the literature. For each supernova yield, we perform parameter surveys and search for configurations that produce the best-fit model and best-rate model using the Perseus Cluster as the reference. From the survey, we study how individual chemical elements affect the contributions of massive stars and Type Ia supernovae in the cosmic chemical enrichment

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arXiv2026

Revisiting the Perseus Cluster III: Role of Aspherical Explosions on its Chemical Composition and Extension to Metal-Poor Stars and Galaxies

The Perseus Cluster has been precisely measured by the legacy Hitomi telescope on the Si-group (Si, S, Ar, Ca) and Fe-group elements (Cr, Mn, Ni). These element abundance ratios provide insight into the typical behaviour of supernovae. In Paper II, we presented new massive star explosion models at various metallicity, assuming spherical explosions. We show that while the fitting is improved, some features (e.g., Ni/Fe) remain to be improved. In this article, we extend our calculation to an aspherical explosion using the jet-induced explosion mechanism. The detailed pre- and post-explosion chemical profiles are calculated with a large post-processing network to capture the production of odd-number elements (V, Mn, Cu) and iron-group elements. We further explore how the jet-driven explosions create the diversity of models which could be compatible with the observed diversity in terms of $^{56}$Ni-mass vs ejecta mass, Ti-V relation, and stellar abundances. Finally, we apply the new collapsar models in the Galactic Chemical Evolution context. We study how the galactic stars, including the Zn-enriched star HE 1327-2326, can put constraints on the relative rates of collapsar and some of its model parameters. We show that collapsar could lead to significant changes in some elements, e.g., Zn. Our study shows that the collapsar is a necessary component to explain multiple elemental trends observed in the Milky Way Galaxy.

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arXiv2026

The impact of new ($α$, n) reaction rates on the weak s-process in metal-poor massive stars

Massive stars are significant sites for the weak s-process (ws-process). $^{22}$Ne and $^{16}$O are, respectively, the main neutron source and poison for the ws-process. In the metal-poor stars, the abundance of $^{22}$Ne is limited by the metallicity, so that the contribution of $^{22}$Ne($α$, n)$^{25}$Mg reaction on the s-process is weaker. Conversely, the $^{17}$O($α$, n)$^{20}$Ne reaction becomes more prominent in these stars due to the most abundant $^{16}$O in all metallicities. In this work, we calculate the evolution of four metal-poor models ($Z=10^{-3}$) for the Zero-Age Main-Sequence (ZAMS) masses of $M ({\rm ZAMS})=$ 15, 20, 25, and 30 M$_{\odot}$ to investigate the effect of reaction rates on the ws-process. We adopt the new $^{17}$O($α$, n)$^{20}$Ne and $^{17}$O($α, γ$)$^{21}$Ne reaction rates suggested by Best et al. (2013) and $^{22}$Ne($α$, n)$^{25}$Mg and $^{22}$Ne($α, γ$)$^{26}$Mg from Wiescher et al. (2023). The yields of the s-process isotope with updated reaction rates are compared with the results using default reaction rates from JINA REACLIB. We find that the new $^{17}$O+$α$ reaction rates increase the ws-process mainly in all the stages, while the new $^{22}$Ne+$α$ reaction rates only increase the ws-process in C and Ne burning stages. Updating these new reaction rates would increase the production of ws-process isotopes by tens of times. We also note that for more massive stars, the enhancement by new $^{17}$O+$α$ reaction rates become more significant.

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arXiv2025

Impacts of the $^{16}$O($^{16}$O, n)$^{31}$S reaction rate on the evolution and nucleosynthesis in Pop III massive stars

We first present a systematic investigation into the effect of the $^{16}$O($^{16}$O, n)$^{31}$S reaction rate on the evolution and nucleosynthesis of Population III (Pop III) stars. We simulate the evolution of a 15 M$_\odot$ Pop III star from the zero-age main sequence through to core collapse, while varying the $^{16}$O($^{16}$O, n)$^{31}$S reaction rate by factors of 0.1, 1, and 10. Our results demonstrate that increasing this reaction rate prompts earlier onset and extended duration of core oxygen burning at lower temperatures and densities. A higher reaction rate also increases neutron excess in OSi-rich layers, thereby promoting the synthesis of neutron-rich isotopes, particularly $^{31}$P and $^{39}$K. Most notably, the K yield is enhanced by a factor of 6.4. For a tenfold enhancement of the $^{16}$O($^{16}$O, n)$^{31}$S rate, the predicted [K/Ca] and [K/Fe] values from presupernova models reach 0.29 and 0.22 dex, respectively-values that are consistent with the most recent observational data for extremely metal-poor stars. These findings hold promise as a potential new solution to the problem of potassium underproduction and offer a valuable theoretical reference and motivation for subsequent measurements of oxygen fusion reaction rate.

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arXiv2025

Primordial Black Hole Triggered Type Ia Supernovae I: Impact on Explosion Dynamics and Light Curves

Primordial black holes (PBHs) in the asteroid-mass window are compelling dark matter candidates, made plausible by the existence of black holes and by the variety of mechanisms of their production in the early universe. If a PBH falls into a white dwarf (WD), the strong tidal forces can generate enough heat to trigger a thermonuclear runaway explosion, depending on the WD mass and the PBH orbital parameters. In this work, we investigate the WD explosion triggered by the passage of PBH. We perform 2D simulations of the WD undergoing thermonuclear explosion in this scenario, with the predicted ignition site as the parameter assuming the deflagration-detonation transition model. We study the explosion dynamics and predict the associated light curves and nucleosynthesis. We find that the model sequence predicts the light curves which align with the Phillip's relation ($B_{\max}$ vs. $ΔM_{15}$). Our models hint at a unifying approach in triggering Type Ia supernovae without involving two distinctive evolutionary tracks.

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arXiv2025

Revisiting the Perseus Cluster I: Resolving the Si/S/Ar/Ca ratios by Stellar Convection

Chemical abundance measurements from stars in the Milky Way to the intragalactic medium in the Perseus Cluster have challenged the spherical explosion models. Models in the literature cannot closely match the observed element ratios, where Si, S are overproduced and Ar, Ca are underproduced. In this article, we explore the impact of the model parameters during the evolution of massive stars on the final explosive nucleosynthesis. We investigate the effects of a parametrized model of the convective process, including the mixing length parameter and the semi-convection parameter, on the production of Si-group elements. We search for the value pair that can reduce the discrepancy in the models. We conclude that a mixing length parameter of 2.2 and semi-convection parameter of 0.03 are required to fit these criteria. Using this updated value pair, we compute a sequence of massive star models from $M_{\rm ZAMS} = $ 15 -- 40 $M_{\odot}$. The high resolution data from future observations such as XRISM will provide further details on less constrained processes in stellar evolution and supernova explosion. Future comparison with supernova models of various progenitor metallicity will further shed light on the supernova population and their relative rates on cosmological scales.

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arXiv2025

Fe Abundances of Early Galaxies at $z=9-12$ Derived with Deep JWST Spectra

We derive Fe-abundance ratios of 7 galaxies at $z=9-12$ with $-22<M_{\mathrm{UV}}<-19$ whose JWST/NIRSpec spectra achieve very high signal-to-noise ratios, $\mathrm{SNR}=60-320$, at the rest-frame UV wavelength. We fit stellar population synthesis model spectra to these JWST spectra, masking out nebular emission lines, and obtain Fe-abundance ratios of $\mathrm{[Fe/H]}=-1-0$ dex for 5 galaxies and upper limits of $\mathrm{[Fe/H]}\sim-2-0$ dex for 2 galaxies. We compare these [Fe/H] values with the oxygen abundances of these galaxies ($7.4<12+\log{\mathrm{(O/H)}}<8.4$) in the same manner as previous studies of $z\sim2-6$ galaxies, and derive oxygen-to-iron abundance ratios [O/Fe]. We find that 2 out of 7 galaxies, GS-z11-0 and GN-z11, show Fe enhancements relative to O ($\mathrm{[O/Fe]}<0$ dex), especially GS-z11-0 ($z=11.12$) with a Fe enhancement ($\mathrm{[O/Fe]}=-0.68_{-0.55}^{+0.37}$ dex) beyond the solar-abundance ratio at $\sim2σ$. Because, unlike GS-z11-0, GN-z11 ($z=10.60$) may be an AGN, we constrain [O/Fe] via FeII emission under the assumption of AGN and confirm that the Fe enhancement is consistent even in the case of AGN. While [O/Fe] values of most galaxies are comparable to those of core-collapse supernovae (CCSNe) yields, the Fe enhancements of GS-z11-0 and GN-z11 are puzzling. We develop chemical evolution models, and find that the Fe enhancements in GS-z11-0 and GN-z11 can be explained by 1) pair-instability supernovae/bright hypernovae with little contribution of CCSNe or 2) Type-Ia supernovae with short delay time ($\sim30-50$ Myr) with a top-light initial mass function.

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arXiv2025

A Common Origin of Normal Type Ia Supernovae Suggested by the Photometric Diversity

In recent years, with an increasing number of type Ia supernovae (SNe Ia) discovered soon after their explosions, a non-negligible fraction of SNe Ia with early-excess emissions (EExSNe Ia) have been confirmed. In this letter, we present a total of \textbf{67} early-phase normal SNe Ia from published papers and ongoing transient survey projects to systematically investigate their photometric behaviors from very early time. We found that EExSNe Ia in our sample have longer rise and brighter peak luminosities compared to those of non-EExSNe Ia. Moreover, EExSNe Ia commonly have ``red-bump" features in the early $B-V$ color while non-EExSNe Ia show blueward evolution from the very beginning. Here, we propose that the thin-helium double-detonation scenario can phenomenologically explain the photometric diversities of normal SNe Ia considering different white dwarf-He-shell mass combinations and the viewing-angle effect, implying a unified explosion mechanism of normal-type SNe Ia. To further testify the possible common origin of normal SNe Ia, systematical studies of multiband photometric and spectral properties of early-phase SNe Ia through the new generation wide-field time-domain survey facilities and global real-time follow-up networks are highly demanded.

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arXiv2025

The chemical yields of stars in the range 9-15 Msun

In Limongi et al. (2024) we presented and discussed the main evolutionary properties and final fate of stars in the mass range 7-15 Msun. The evolutions of those models were computed by means of a medium size nuclear network that guaranteed a proper calculation of the nuclear energy generation and hence a good modeling of the physical evolution of these stars. In the present paper, we extend this study by computing the detailed chemical yields of stars in the mass range 9-15 Msun, i.e., those stars that explode as core collapse supernovae (CCSNe). The explosive nucleosynthesis is then computed in the framework of the thermal bomb induced explosion by means of the HYPERION code (Limongi and Chieffi 2020). We find that: (1) the yields of the intermediate mass elements (i.e., O to P) show a steep decrease as the inital mass decreases; (2) the yields of s-weak component, i.e., those produced by the slow neutron captures from Ga to to the first neutron closure shell, decrease almost linearly as a function of the initial mass with respect to the ones produced by the more massive stars; (3) the global contribution of the stars in the mass range 9.22-13 Msun to the yields of a generation of massive stars averaged over a standard initial mass function is negligible for essentially all the isotopes. In spite of this, however, the models of stars in this mass range can be fundamental to interpret the observations of specific supernovae.

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arXiv2025

The Impact of $^{12}$C($α, γ$)$^{16}$O Reaction on the Presupernova Evolution and Supernova Explodability of Massive Stars

Among the uncertainties of stellar evolution theory, we investigate how the $^{12}$C($α, γ$)$^{16}$O reaction rate affects the evolution of massive stars for the initial masses of $M ({\rm ZAMS})=$ 13 - 40 M$_\odot$ and the solar metallicity. We show that the {\sl explodability} of these stars, i.e., which of a neutron star (NS) or a black hole (BH) is formed, is sensitive to the strength of convective shell burning of C and O, and thus the mass fractions of C ($X$(C)) and O in the shell. For the small $^{12}$C($α, γ$)$^{16}$O reaction rate that yields larger $X$(C), $X$(C) is further enhanced by mixing of C from the overlying layer and then C shell burning is strengthened. The extra heating by C shell burning tends to prevent the contraction of outer layers and decrease the {\sl compactness parameter} at $M_r$ = 2.5 M$_\odot$. This effect leads to the formation of smaller mass cores of Si and Fe and steeper density and pressure gradients at the O burning shell in the presupernova models. If the pressure gradient there is steeper, the model is more likely to explode to form a NS rather than a BH. We describe the pressure gradient against $M_r$ with $V/U$ and the density drop with $1/U$, where $U$ and $V$ are non-dimensional variables to describe the stellar structure. We estimate the critical values of $V/U$ and $1/U$ at the O-burning shell above which the model is more likely to explode. We conclude that the smaller $^{12}$C($α, γ$)$^{16}$O reaction rate makes the mass range of $M ({\rm ZAMS})$ that forms a NS larger.

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arXiv2024

Hydrodynamics and Nucleosynthesis of Jet-Driven Supernovae II: Comparisons with Abundances of Extremely Metal-Poor Galaxies and Constraints on Supernova Progenitors

The spectra of several galaxies, including extremely metal-poor galaxies (EMPGs) from the EMPRESS survey, have shown that the abundances of some Si-group elements differ from "spherical" explosion models of massive stars. This leads to the speculation that these galaxies have experienced supernova explosions with high asphericity, where mixing and fallback of the inner ejecta with the outer material leads to the distinctive chemical compositions. In this article, we consider the jet-driven supernova models by direct two-dimensional hydrodynamics simulations using progenitors about 20 -- 25 $M_{\odot}$ at zero metallicity. We investigate how the abundance patterns depend on the progenitor mass, mass cut and the asphericity of the explosion. We compare the observable with available supernova and galaxy catalogs based on $^{56}$Ni, ejecta mass, and individual element ratios. The proximity of our results with the observational data signifies the importance of aspherical supernova explosions in chemical evolution of these galaxies. Our models will provide the theoretical counterpart for understanding the chemical abundances of high-z galaxies measured by the James Webb Space Telescope.

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arXiv2024

Low [O/Fe] Ratio in a Luminous Galaxy at the Early Cosmic Epoch ($z>10$): Signature of Short Delay Time or Bright Hypernovae/Pair-Instability Supernovae?

We present an [O/Fe] ratio of a luminous galaxy GN-z11 at $z=10.60$ derived with the deep public JWST/NIRSpec data. We fit the medium-resolution grating (G140M, G235M, and G395M) data with the model spectra consisting of BPASS-stellar and CLOUDY-nebular spectra in the rest-frame UV wavelength ranges with Fe absorption lines, carefully masking out the other emission and absorption lines in the same manner as previous studies conducted for lower redshift ($z\sim 2-6$) galaxies with oxygen abundance measurements. We obtain an Fe-rich abundance ratio $\mathrm{[O/Fe]}=-0.37^{+0.43}_{-0.22}$, which is confirmed with the independent deep prism data as well as by the classic 1978 index method. This [O/Fe] measurement is lower than measured for star-forming galaxies at $z\sim 2-3$. Because $z=10.60$ is an early epoch after the Big Bang ($\sim 430$ Myr) and the first star formation (likely $\sim 200$ Myr), it is difficult to produce Fe by Type Ia supernovae (SNeIa) requiring sufficient delay time for white-dwarf formation and gas accretion. The Fe-rich abundance ratio in GN-z11 suggests that the delay time is short, or that the major Fe enrichment is not accomplished by SNeIa but bright hypernovae (BrHNe) and/or pair-instability supernovae (PISNe), where the yield models of BrHNe and PISNe explain Fe, Ne, and O abundance ratios of GN-z11. The [O/Fe] measurement is not too low to rule out the connection between GN-z11 and globular clusters (GCs) previously suggested by the nitrogen abundance, but rather supports the connection with a GC population at high [N/O] if a metal dilution process exists.

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arXiv2024

Nebular Nitrogen Line Emission in Stripped-Envelope Supernovae -- a New Progenitor Mass Diagnostic

Nitrogen is produced by CNO-cycling in massive stars, and can be ejected in significant amounts in supernova explosions. While in H-rich SNe, its [\ion{N}{II}] 6548, 6583 emission becomes obscured by strong H$α$, in explosions of He stars, this nitrogen emission becomes more visible. We here explore the formation of this line, using the \texttt{SUMO} code to compute spectra for a grid of 1D models with parameterized mixing informed from new 2D simulations. Because the mass fraction of nitrogen in the ejecta decreases with larger He core masses, as more of the He/N zone gets processed by shell helium burning and is lost to winds, the [\ion{N}{II}] luminosity relative to the overall optical flux probes the He core mass. By comparing to large samples of data, we find that low-mass He cores ($M_{\rm preSN}\lesssim\ 3\ M_\odot$) are exclusively associated with Type IIb SNe, with the exception of Type Ib SN 2007Y. Seeing no strong nitrogen emission in other Type Ib SNe, the implication is either an origin from low-mass stars with the He/N layer (but not the He/C) layer peeled away, or from higher-mass He cores. We also see no clear nitrogen emission in Type Ic SNe. We discuss the diagnostic potential of this new line metric, and also dependencies on mass-loss-rate and metallicity.

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arXiv2024

EMPRESS. XIII. Chemical Enrichments of Young Galaxies Near and Far at z ~ 0 and 4-10: Fe/O, Ar/O, S/O, and N/O Measurements with Chemical Evolution Model Comparisons

We present gas-phase elemental abundance ratios of 7 local extremely metal-poor galaxies (EMPGs) including our new Keck/LRIS spectroscopy determinations together with 33 JWST $z\sim 4-10$ star-forming galaxies in the literature, and compare chemical evolution models. We develop chemical evolution models with the yields of core-collapse supernovae (CCSNe), Type Ia supernovae, hypernovae (HNe), and pair-instability supernovae (PISNe), and compare the EMPGs and high-$z$ galaxies in conjunction with dust depletion contributions. We find that high Fe/O values of EMPGs can (cannot) be explained by PISN metal enrichments (CCSN/HN enrichments even with the mixing-and-fallback mechanism enhancing iron abundance), while that the observed Ar/O and S/O values are much smaller than the predictions of the PISN models. The abundance ratios of the EMPGs can be explained by the combination of Type Ia SNe and CCSNe/HNe whose inner layers of argon and sulfur mostly fallback, which are comparable with Sculptor stellar chemical abundance distribution, suggesting that early chemical enrichment is taken place in the EMPGs. Comparing our chemical evolution models with the star-forming galaxies at $z\sim 4-10$, we find that the Ar/O and S/O ratios of the high-$z$ galaxies are comparable with those of the CCSNe/HNe models, while majority of the high-$z$ galaxies do not have constraints good enough to rule out contributions from PISNe. The high N/O ratio recently reported in GN-z11 cannot be explained even by rotating PISNe, but could be reproduced by the winds of rotating Wolf Rayet stars that end up as a direct collapse.

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arXiv2023

Evolution and final fate of solar metallicity stars in the mass range 7-15 Msun. I. The transition from AGB to SAGB stars, Electron Capture and Core Collapse Supernovae progenitors

According to a standard initial mass function, stars in the range 7-12 Msun constitute ~50% (by number) of the stars more massive than ~7 Msun, but, in spite of this, their evolutionary properties, and in particular their final fate, are still scarcely studied. In this paper we present a detailed study of the evolutionary properties of solar metallicity, non rotating stars in the range 7-15 Msun, from the pre main sequence phase up to the presupernova stage or up to an advanced stage of the thermally pulsing phase, depending on the initial mass. We find that (1) the 7.00 Msun develops a degenerate CO core and evolves as a classical AGB star in the sense that it does not ignite the C burning reactions; (2) stars with the initial mass M >= 9.22 Msun end their life as core collapse supernovae; (3) stars in the range 7.50 <= M/Msun <= 9.20 develop a degenerate ONeMg core and evolve through the thermally pulsing SAGB phase; 4) stars in the mass range 7.50 <= M/Msun <= 8.00 end their life as hybrid CO/ONeMg- or ONeMg- WD; (5) stars with the initial mass in the range 8.50 <= M/Msun <= 9.20 may potentially explode as electron capture supernovae.

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