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Related papers: s-process branching at 185W revised

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We model the nucleosynthesis during a radiative interpulse phase of a rotating 3Msun Asymptotic Giant Branch (AGB) star. We find an enhanced production of the neutron source species C13 compared to non-rotating models due to shear mixing of…

Astrophysics · Physics 2007-05-23 Falk Herwig , Norbert Langer , Maria Lugaro

We present a selection technique to detect Compton-thick (CT) active galactic nuclei (AGNs) in the 3XMM/SDSS-DR7 cross-correlation. A subsample of 3481 X-ray sources that are detected in the hard band (2-8 keV) and have photometric…

Astrophysics of Galaxies · Physics 2023-09-27 Reham Mostafa , Matteo Guainazzi , Alaa Ibrahim

Fermi LAT has detected gamma ray emissions from the core of Cen A. More recently, a new component in the gamma ray spectrum from the core has been reported in the energy range of 4 GeV to tens of GeV. We show that the new component and the…

High Energy Astrophysical Phenomena · Physics 2014-05-02 Esha Kundu , Nayantara Gupta

Recent observations have revealed an interesting active galactic nuclei (AGN) subclass that shows strong activity at large scales ($\sim1$ kpc) but weaker at small scales ($<10$ pc), suggesting a strong change in the mass accretion rate of…

Astrophysics of Galaxies · Physics 2022-10-26 J. Pflugradt , K. Ichikawa , M. Akiyama , M. Kokubo , B. Vijarnwannaluk , H. Noda , X. Chen

We have observed the nucleus of the nearby luminous infrared galaxy NGC 4418 with subarcsec resolution at 860 and 450 micron for the first time to characterize its hidden power source. A ~20 pc (0.1") hot dusty core was found inside a 100…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Kazushi Sakamoto , Susanne Aalto , Francesco Costagliola , Sergio Martin , Youichi Ohyama , Martina C. Wiedner , David J. Wilner

In this work, we present new data on the $^{182,183,184}$W($\gamma,n$) cross sections, utilizing a quasi-monochromatic photon beam produced at the NewSUBARU synchrotron radiation facility. Further, we have extracted the nuclear level…

Recent studies suggest that binary neutron star (NS-NS) mergers robustly produce the heavy r-process nuclei above the atomic mass number A ~ 130 because of their ejecta consisting of almost pure neutrons (electron fraction of Y_e < 0.1).…

Solar and Stellar Astrophysics · Physics 2015-06-18 Shinya Wanajo , Yuichiro Sekiguchi , Nobuya Nishimura , Kenta Kiuchi , Koutarou Kyutoku , Masaru Shibata

We present the HST ACS G800L grism spectroscopy observation of the faint active galactic nuclei (AGN) candidates in the COSMOS field at redshift of 6 selected by the point-source morphology and the photometry drop-off at 8000\AA. Among the…

Mono-energetic $\gamma$-beams ($\Delata \approx$ 10 eV) based on thermal neutron capture, in a nuclear reactor, using the Mn(n, $\gamma$) reaction were utilized for generating a fast neutron source from Zinc, via the ${67}^Zn(\gamma, n)$…

Nuclear Experiment · Physics 2024-01-15 Sylvian Kahane , Raymond Moreh

(abridged) We model the nucleosynthesis during the thermal pulse phase of a rotating, solar metallicity AGB star of 3M_sun. Rotationally induced mixing during the thermal pulses produces a layer (~2E-5M_sun) on top of the CO-core where…

Astrophysics · Physics 2009-11-07 Falk Herwig , Norbert Langer , Maria Lugaro

The reaction $^{17}$O$(p,\gamma)^{18}$F influences hydrogen-burning nucleosynthesis in several stellar sites, such as red giants, asymptotic giant branch (AGB) stars, massive stars and classical novae. In the relevant temperature range for…

Abundances of Mo isotopes predicted by stellar models of the s process are, except for 95Mo, in good agreement with data from single grains of mainstream presolar SiC. Because the meteorite data seemed sound and no reasonable modification…

Astrophysics · Physics 2008-09-17 P. E. Koehler , J. A. Harvey , K. H. Guber , D. Wiarda

Carbon-enhanced metal-poor (CEMP) stars in the Galactic Halo display enrichments in heavy elements associated with either the s (slow) or the r (rapid) neutron-capture process (e.g., barium and europium respectively), and in some cases they…

Solar and Stellar Astrophysics · Physics 2016-11-15 Melanie Hampel , Richard J. Stancliffe , Maria Lugaro , Bradley S. Meyer

The chemical content of the planetary nebula NGC 3918 is investigated through deep, high-resolution (R~40000) UVES at VLT spectrophotometric data. We identify and measure more than 750 emission lines, making ours one of the deepest spectra…

Solar and Stellar Astrophysics · Physics 2015-10-16 S. Madonna , J. García-Rojas , V. Luridiana , N. C. Sterling , C. Morisset

We have made a parametric study of s-process nucleosynthesis in the metal poor ([Fe/H]=-2.7) stars LP625-44 and LP706-7. We find that a high neutron exposure and a small overlap factor are necessary to fit the abundance pattern observed in…

We present a new nucleosynthesis process, that we denote nu p-process, which occurs in supernovae (and possibly gamma-ray bursts) when strong neutrino fluxes create proton-rich ejecta. In this process, antineutrino absorptions in the…

During hard X-ray observations of the Norma spiral arm region by the Nuclear Spectroscopic Telescope Array (NuSTAR) in 2013 February, a new transient source, NuSTAR J163433-4738.7, was detected at a significance level of 8-sigma in the 3-10…

We examine the 0.1 to 10.0 keV X-ray spectrum of the bright nuclear LINER galaxy NGC 1052, one of two elliptical galaxies known to contain a luminous H2O maser. The observed 2.0-10.0 keV spectrum is unusually flat (photon index Gamma~0.2)…

Astrophysics · Physics 2009-10-31 K. A. Weaver , A. S. Wilson , C. Henkel , J. A. Braatz

We analyse star formation in the nuclei of 9 Seyfert galaxies at spatial resolutions down to 0.085arcsec, corresponding to length scales of less than 10pc in some objects. Our data were taken mostly with the near infrared adaptive optics…

Astrophysics · Physics 2009-11-13 R. Davies , F. Mueller Sanchez , R. Genzel , L. Tacconi , E. Hicks , S. Friedrich , A. Sternberg

Adopting the hypothesis that the nonthermal emission of Active Galactic Nuclei (AGN) is primarily due to the acceleration of protons, we construct a simple model in which the interplay of acceleration and losses can be studied together with…

Astrophysics · Physics 2008-02-03 A. Mastichiadis J. G. Kirk