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We discuss the application of a strong-coupling expansion (perturbation theory in the hopping) for studying light-Fermi-heavy-Bose (like $^{40}$K-$^{87}$Rb) mixtures in optical lattices. We use the strong-coupling method to evaluate the…

Quantum Gases · Physics 2011-05-31 Anzi Hu , J. K. Freericks , M. M. Maśka , C. J. Williams

In this first paper of a series, we report on the use of quasar spectra obtained with the UVES high resolution spectrograph and available through the ESO VLT archive to build the first sample of sub-DLA systems, absorbers with HI column…

Astrophysics · Physics 2009-11-10 M. Dessauges-Zavadsky , C. Peroux , T. -S. Kim , S. D'Odorico , R. G. McMahon

We present the latest improvements in the Center for Radiative Shock Hydrodynamics (CRASH) code, a parallel block-adaptive-mesh Eulerian code for simulating high-energy-density plasmas. The implementation can solve for radiation models with…

Solar and Stellar Astrophysics · Physics 2012-06-08 B. van der Holst , G. Toth , I. V. Sokolov , B. R. Torralva , K. G. Powell , R. P. Drake

We present a formulation and numerical algorithm to extend the scheme for grey radiation magneto-hydrodynamics (MHD) developed by Jiang (2021) to include the frequency dependence via the multi-group approach. The entire frequency space can…

Instrumentation and Methods for Astrophysics · Physics 2022-09-15 Yan-Fei Jiang

Thick diffractive optical elements offer a promising way to achieve focusing or imaging at a resolution approaching 1 nm for X-ray wavelengths shorter than about 0.1 nm. Efficient focusing requires that these are fabricated with structures…

Optics · Physics 2020-12-02 Henry N. Chapman , Saša Bajt

We describe RAGE, the ``Radiation Adaptive Grid Eulerian'' radiation-hydrodynamics code, including its data structures, its parallelization strategy and performance, its hydrodynamic algorithm(s), its (gray) radiation diffusion algorithm,…

Intensive reverberation mapping monitoring programs combine ground-based photometric observations from different telescopes, requiring intercalibration of lightcurves to reduce systematic instrumental differences. We present a new iterative…

Instrumentation and Methods for Astrophysics · Physics 2025-06-02 Roberta Vieliute , Juan V. Hernández Santisteban , Keith Horne , Hannah Cornfield

To understand the conditions under which dense, molecular gas is able to form within a galaxy, we post-process a series of three-dimensional galactic-disk-scale simulations with ray-tracing based radiative transfer and chemical network…

We propose a novel approach to site-resolved detection of a 2D gas of ultracold atoms in an optical lattice. A near resonant laser beam is coherently scattered by the atomic array and its interference pattern is holographically recorded by…

2D face analysis techniques, such as face landmarking, face recognition and face verification, are reasonably dependent on illumination conditions which are usually uncontrolled and unpredictable in the real world. An illumination robust…

Computer Vision and Pattern Recognition · Computer Science 2017-10-17 Wuming Zhang , Xi Zhao , Jean-Marie Morvan , Liming Chen

We present and test chemical models for three-dimensional hydrodynamical simulations of galaxies. We explore the effect of changing key parameters such as metallicity, radiation and non-equilibrium versus equilibrium metal cooling…

Astrophysics of Galaxies · Physics 2016-05-04 Stefano Bovino , Tommaso Grassi , Pedro R. Capelo , Dominik R. G. Schleicher , R. Banerjee

The 21 cm hyperfine transition of the atomic hydrogen (HI) in ground state is a powerful probe of the neutral gas content of the universe. This radio frequency transition has been used routinely for decades to observe, both in emission and…

Astrophysics of Galaxies · Physics 2019-11-26 Preetha Saha , Nirupam Roy , Mukul Bhattacharya

Aims. We present a new radiation hydrodynamics code, called "ARK-RT" which uses a two-moment model with the M1 closure relation for radiative transfer. This code aims at being ready for high-performance computing, on exascale architectures.…

Instrumentation and Methods for Astrophysics · Physics 2021-02-24 H. Bloch , P. Tremblin , M. González , T. Padioleau , E. Audit

As new large-scale astronomical surveys greatly increase the number of objects targeted and discoveries made, the requirement for efficient follow-up observations is crucial. Adaptive optics imaging, which compensates for the image-blurring…

Emerging quality requirements in modern optical systems increase the need for accurate simulation and compensation of disturbances. One key disturbance in high-power laser applications results from thermal loading due to absorption. This…

Optics · Physics 2025-06-24 Mark Kurcsics , Peter Eberhard

In a recent paper, we have proposed a novel laser cooling scheme for reducing collisional energy of a pair of atoms by using photoassociative transitions. In that paper, we considered two atoms in free space, that is we have not considered…

Atomic Physics · Physics 2017-03-22 Somnath Naskar , Subrata Saha , Partha Goswami , Arpita pal , Bimalendu Deb

We have developed a new computer code, RAM, to solve the conservative equations of special relativistic hydrodynamics (SRHD) using adaptive mesh refinement (AMR) on parallel computers. We have implemented a characteristic-wise, finite…

Astrophysics · Physics 2009-11-11 Weiqun Zhang , Andrew I. MacFadyen

Infrared avalanche photodiode arrays represent a panacea for many branches of astronomy by enabling extremely low-noise, high-speed and even photon-counting measurements at near-infrared wavelengths. We recently demonstrated the use of an…

Instrumentation and Methods for Astrophysics · Physics 2015-08-19 Christoph Baranec , Dani Atkinson , Reed Riddle , Donald Hall , Shane Jacobson , Nicholas M. Law , Mark Chun

Substellar companions such as exoplanets and brown dwarfs exhibit changes in brightness arising from top-of-atmosphere inhomogeneities, providing insights into their atmospheric structure and dynamics. This variability can be measured in…

Absorption-line spectroscopy is a powerful tool used to estimate element abundances in the nearby as well as distant universe. The accuracy of the abundances thus derived is, naturally, limited by the accuracy of the atomic data assumed for…

Instrumentation and Methods for Astrophysics · Physics 2015-06-17 Romas Kisielius , Varsha P. Kulkarni , Gary J. Ferland , Pavel Bogdanovich , Matt L. Lykins