Radioactive nuclei in the early Solar System: Analysis of the 15 isotopes produced by core-collapse supernovae

Short-lived radioactive isotopes (SLRs) with half-lives between 0.1 to 100 Myr can be used to probe the origin of the Solar System. In this work, we examine the core-collapse supernovae production of the 15 SLRs produced: 26Al, 36Cl, 41Ca, 53Mn, 60Fe, 92Nb, 97Tc, 98Tc, 107Pd, 126Sn, 129I, 135Cs, 146Sm, 182Hf, and 205Pb. We probe the impact of the uncertainties of the core-collapse explosion mechanism by examining a collection of 62 core-collapse models with initial masses of 15, 20, and 25 M⊙, explosion energies between 3.4 × 1050 and 1.8 × 1052 ergs and compact remnant masses between 1.5 M⊙ and 4.89 M⊙. We identify the impact of both explosion energy and remnant mass on the final yields of the SLRs. Isotopes produced within the innermost regions of the star, such as 92Nb and 97Tc, are the most affected by the remnant mass, 92Nb varying by five orders of magnitude. Isotopes synthesised primarily in explosive C-burning and explosive He-burning, such as 60Fe, are most affected by explosion energies. 60Fe increases by two orders of magnitude from the lowest to the highest explosion energy in the 15 M⊙ model. The final yield of each examined SLR is used to compare to literature models

Type Ia Supernova Nucleosynthesis: Metallicity-dependent Yields

Type Ia supernova explosions (SN Ia) are fundamental sources of elements for the chemical evolution of galaxies. They efficiently produce intermediate-mass (with Z between 11 and 20) and iron group elements - for example, about 70% of the solar iron is expected to be made by SN Ia. In this work, we calculate complete abundance yields for 39 models of SN Ia explosions, based on three progenitors - a 1.4 M ⊙ deflagration detonation model, a 1.0 M ⊙ double detonation model, and a 0.8 M ⊙ double detonation model - and 13 metallicities, with 22Ne mass fractions of 0, 1 × 10-7, 1 × 10-6, 1 × 10-5, 1 × 10-4, 1 × 10-3, 2 × 10-3, 5 × 10-3, 1 × 10-2, 1.4 × 10-2, 5 × 10-2, and 0.1, respectively. Nucleosynthesis calculations are done using the NuGrid suite of codes, using a consistent nuclear reaction network between the models. Complete tables with yields and production factors are provided online at Zenodo:Yields (https://doi.org/10.5281/zenodo.8060323). We discuss the main properties of our yields in light of the present understanding of SN Ia nucleosynthesis, depending on different progenitor mass and composition. Finally, we compare our results with a number of relevant models from the literature

Type Ia Supernova Nucleosynthesis: Metallicity-Dependent Yields

Type Ia supernova explosions (SNIa) are fundamental sources of elements for the chemical evolution of galaxies. They efficiently produce intermediate-mass (with Z between 11 and 20) and iron group elements - for example, about 70% of the solar iron is expected to be made by SNIa. In this work, we calculate complete abundance yields for 39 models of SNIa explosions, based on three progenitors - a 1.4M deflagration detonation model, a 1.0 double detonation model and a 0.8 M double detonation model - and 13 metallicities, with 22Ne mass fractions of 0, 1x10-7, 1x10-6, 1x10-5, 1x10-4, 1x10-3, 2x10-3, 5x10-3, 1x10-2, 1.4x10-2, 5x10-2, and 0.1 respectively. Nucleosynthesis calculations are done using the NuGrid suite of codes, using a consistent nuclear reaction network between the models. Complete tables with yields and production factors are provided online at Zenodo: Yields. We discuss the main properties of our yields in the light of the present understanding of SNIa nucleosynthesis, depending on different progenitor mass and composition. Finally, we compare our results with a number of relevant models from the literature.Comment: 42 pages, 21 figures. Accepted for publication in ApJS 21-06-2

The Grizzly, March 22, 1994

Public Not Pleased with Health Care Proposal • Tax-Exempt Status Challenged • J-Board Issues Punishment for Illegal Pledging Activity • U.S.G.A. Minutes • Letter to the Senior Class • Students Respond to Editor\u27s View on Pledging • Editor Clarifies Position • Awareness Needed • Investigative Team Responds • The Madness is Here: Update on the NCAA Tournament • Track & Field to Begin Seasonhttps://digitalcommons.ursinus.edu/grizzlynews/1333/thumbnail.jp

Graphene-doped photo-patternable ionogels: tuning of conductivity and mechanical stability of 3D microstructures

This work reports for the first time the development of enhanced conductivity, graphene- doped photo-patternable hybrid organic-inorganic ionogels and the effect of the subsequent materials condensation on the conductivity and mechanical stability of three- dimensional microstructures fabricated by multi-photon polymerisation (MPP). Ionogels were based on photocurable silicon/zirconium hybrid sol-gel materials and phosphonium (trihexyltetradecylphosphonium dicyanamide [P6,6,6,14][DCA] ionic liquid (IL). To optimise the dispersion of graphene within the ionogel matrices, aqueous solutions of graphene were prepared, as opposed to the conventional graphene powder approach, and employed as catalysts of hydrolysis and condensation reactions occurring in the sol-gel process. Ionogels were prepared via a two step process by varying the hydrolysis degree from 25 to 50%, IL content between 0-50 w/w%, and the inorganic modifier (zirconate complex) concentration from 30 to 60 mol.% against the photocurable ormosil and they were characterised via Raman, Electrochemical Impedance Spectroscopy and Transmission Electron Microscopy. MPP was performed on the hybrid ionogels, resulting in three- dimensional microstructures that were characterised using scanning electron microscopy. It is clearly demonstrated that the molecular formulation of the ionogels, including the concentration of graphene and the zirconate network modifier, play a critical role in the conductivity of the ionogels and influence the resulting mechanical stability of the fabricated three-dimensional microstructures. This work aims to establish for the first time the relationship between the molecular design and condensation of materials in the physico-chemistry and dynamic of ionogels

The Lantern Vol. 73, No. 2, Spring 2006

• Of the Man • Beauty in America • Kindling • Genevieve • Bits of Copper • A Love Song to Hip Hop • From James\u27 Journal • I Want a Woman • Peregrine Rain • Resurge • Frustrations • (At Least) You Gave Me Something to Write About • The Fun of Giving Interactive History Lectures as a Summer Job • Exigence • White Water • My Summer, with Salt • The City With Two Faces • I Dig Your Cello • Life-Filled Ghost Town • Laura, On Happiness • Integration/Assimilation • Sunny Side Estates • Every Night I Shut My Eyes • New England State of Mind • Your Body\u27s Weight in Water for Your Soul, Thank You Very Much • A Story That\u27s 10 Percent Truehttps://digitalcommons.ursinus.edu/lantern/1168/thumbnail.jp

Catching Element Formation In The Act

Gamma-ray astronomy explores the most energetic photons in nature to address some of the most pressing puzzles in contemporary astrophysics. It encompasses a wide range of objects and phenomena: stars, supernovae, novae, neutron stars, stellar-mass black holes, nucleosynthesis, the interstellar medium, cosmic rays and relativistic-particle acceleration, and the evolution of galaxies. MeV gamma-rays provide a unique probe of nuclear processes in astronomy, directly measuring radioactive decay, nuclear de-excitation, and positron annihilation. The substantial information carried by gamma-ray photons allows us to see deeper into these objects, the bulk of the power is often emitted at gamma-ray energies, and radioactivity provides a natural physical clock that adds unique information. New science will be driven by time-domain population studies at gamma-ray energies. This science is enabled by next-generation gamma-ray instruments with one to two orders of magnitude better sensitivity, larger sky coverage, and faster cadence than all previous gamma-ray instruments. This transformative capability permits: (a) the accurate identification of the gamma-ray emitting objects and correlations with observations taken at other wavelengths and with other messengers; (b) construction of new gamma-ray maps of the Milky Way and other nearby galaxies where extended regions are distinguished from point sources; and (c) considerable serendipitous science of scarce events -- nearby neutron star mergers, for example. Advances in technology push the performance of new gamma-ray instruments to address a wide set of astrophysical questions.Comment: 14 pages including 3 figure

The state of the Martian climate

60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes

Histone Deacetylase Inhibitors Impair the Elimination of HIV-Infected Cells by Cytotoxic T-Lymphocytes

Resting memory CD4+ T-cells harboring latent HIV proviruses represent a critical barrier to viral eradication. Histone deacetylase inhibitors (HDACis), such as suberanilohydroxamic acid (SAHA), romidepsin, and panobinostat have been shown to induce HIV expression in these resting cells. Recently, it has been demonstrated that the low levels of viral gene expression induced by a candidate HDACi may be insufficient to cause the death of infected cells by viral cytopathic effects, necessitating their elimination by immune effectors, such as cytotoxic T-lymphocytes (CTL). Here, we study the impact of three HDACis in clinical development on T-cell effector functions. We report two modes of HDACi-induced functional impairment: i) the rapid suppression of cytokine production from viable T-cells induced by all three HDACis ii) the selective death of activated T-cells occurring at later time-points following transient exposures to romidepsin or, to a lesser extent, panobinostat. As a net result of these factors, HDACis impaired CTL-mediated IFN-γ production, as well as the elimination of HIV-infected or peptide-pulsed target cells, both in liquid culture and in collagen matrices. Romidepsin exerted greater inhibition of antiviral function than SAHA or panobinostat over the dose ranges tested. These data suggest that treatment with HDACis to mobilize the latent reservoir could have unintended negative impacts on the effector functions of CTL. This could influence the effectiveness of HDACi-based eradication strategies, by impairing elimination of infected cells, and is a critical consideration for trials where therapeutic interruptions are being contemplated, given the importance of CTL in containing rebound viremia