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The discovery that the short-lived radionucleide iron-60 was present in the oldest meteorites suggests that the formation of the Earth closely followed the death of a massive star. I discuss three astrophysical origins: winds from an AGB…

Astrophysics · Physics 2017-04-26 Jonathan P. Williams

Superconductor based quantum computing has the major drawback of working temperatures which require liquid helium for cooling. A promising approach to overcome this obstacle for quantum technologies is based on deep level defects in…

Materials Science · Physics 2019-06-19 Michael Schöler , Maximilian W. Lederer , Philipp Schuh , Peter J. Wellmann

Titanium-carbide molecular clusters are thought to form in the circumstellar envelopes (CSEs) of carbon-rich Asymptotic Giant Branch stars (AGBs) but, to date, their detection has remained elusive. To facilitate the astrophysical…

Astrophysics of Galaxies · Physics 2021-10-04 Sergio Gámez-Valenzuela , Julio A. Alonso , Gonzalo Santoro , José I. Martínez

We report Mo isotopic compositions of 37 presolar SiC grains of types Y (19) and Z (18), rare types commonly argued to have formed in lower-than-solar metallicity asymptotic giant branch (AGB) stars. Direct comparison of the Y and Z grain…

Our present understanding of the extragalactic source counts and background radiation at infrared and sub-mm wavelengths is reviewed. Available count data are used to constrain evolutionary models of galaxies and Active Nuclei. The CIRB, on…

We present low spectral resolution molecular interferometric observations at 1.2 mm obtained with the Combined Array for Research in Millimetre-wave Astronomy (CARMA) towards the C-rich AGB star IRC+10216. We have mapped the emission of…

In ion cancer therapy, high-intensity ion beams are used to treat tumors by taking advantage of the Bragg-Peak. Typical ion therapy centers use particle rates up to $10^{10}$ ions/second for treatment. On the other hand, such intensities…

Instrumentation and Detectors · Physics 2022-02-02 Manuel Christanell , Maximilian Tomaschek , Thomas Bergauer

Irradiation with high energy photons (10.2 - 11.8 eV) was applied to small diamondoids isolated in solid rare gas matrices at low temperature. The photoproducts were traced via UV absorption spectroscopy. We found that upon ionization the…

Chemical Physics · Physics 2011-04-20 M. Steglich , F. Huisken , J. E. Dahl , R. M. K. Carlson , Th. Henning

Cosmic birefringence, arising from a potential parity-violating interaction between cosmic microwave background (CMB) photons and evolving pseudo-scalar fields such as axion-like particles, can rotate the CMB polarization plane and induce…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-27 Mathieu Remazeilles

We present three-dimensional (3D) non-local thermodynamic equilibrium (non-LTE) radiative transfer calculations for silicon in the solar photosphere, using an extensive model atom that includes recent, realistic neutral hydrogen collisional…

Solar and Stellar Astrophysics · Physics 2016-09-28 A. M. Amarsi , M. Asplund

We present a new approach aimed at constraining the typical size and optical properties of carbon dust grains in Circumstellar envelopes (CSEs) of carbon-rich stars (C-stars) in the Small Magellanic Cloud (SMC). To achieve this goal, we…

We report contributions to cosmic infrared background (CIB) intensities originating from known galaxies and their faint companions at submillimeter wavelengths. Using the publicly-available UltraVISTA catalog, and maps at 250, 350, and 500…

The cosmic infrared background (CIB) is a powerful probe of large-scale structure across a very large redshift range, and consists of unresolved redshifted infrared emission from dusty galaxies. It can be used to study the astrophysics of…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-02 Daniel Lenz , Olivier Doré , Guilaine Lagache

The present understanding of C-rich AGB chemistry largely relies on observations of the archetypal carbon star IRC+10216. Current molecular abundance estimates for carbon stars are based either on single-dish spectra sampling a range of…

New SiS multi-transition (sub-)millimetre line observations of a sample of AGB stars with varying photospheric C/O-ratios and mass-loss rates are presented. A combination of low- and high-energy lines are important in constraining the…

Astrophysics · Physics 2009-11-13 F. L. Schoeier , J. Bast , H. Olofsson , M. Lindqvist

During the formation of Si nanocrystals (Si NC) in Si$_x$C$_{1-x}$ layers via solid-phase crystallization, the unintended formation of nanocrystalline SiC reduces the minority carrier lifetime and therefore the performance of…

Applied Physics · Physics 2020-05-18 C. Weiss , M. Schnabel , S. Prucnal , J. Hofmann , A. Reichert , T. Fehrenbach , W. Skorupa , S. Janz

Color-center defects in silicon carbide promise opto-electronic quantum applications in several fields, such as computing, sensing and communication. In order to scale down and combine these functionalities with the existing silicon device…

Recently the CIBER experiment measured the diffuse cosmic infrared background (CIB) flux and claimed an excess compared with integrated emission from galaxies. We show that the CIB spectrum can be fitted by the additional photons produced…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-13 Kazunori Kohri , Takeo Moroi , Kazunori Nakayama

We report first results for the cosmic infrared background (CIB) fluctuations at 1.25, 1.65 and 2.17 micron obtained from long exposures constructed from 2MASS standard star fields. We have co-added and analyzed scans from one such field…

Astrophysics · Physics 2009-11-07 A. Kashlinsky , S. Odenwald , J. Mather , M. F. Skrutskie , R. M. Cutri

The electronic structure and absorption spectrum of hydrogenated silicon carbide nanocrystals (SiCNC) have been determined by first principles calculations. We show that the reconstructed surface can significantly change not just the onset…

Materials Science · Physics 2015-05-13 Márton Vörös , Péter Deák , Thomas Frauenheim , Adam Gali