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We use the average E(B-V) and ZnII column densities of a sample of z~1 CaII (3935, 3970) absorption line systems selected from the Sloan Digital Sky Survey (SDSS DR4) to show that on average, with conservative assumptions regarding…

天体物理学 · 物理学 2009-11-11 Vivienne Wild , Paul Hewett , Max Pettini

We present HST spectra for a sample of six QSOs with intermediate redshift (z_a < 1) damped Ly-alpha systems. These observations aim at measuring the HI column density and detect metal lines in order to investigate the metal enrichment of…

天体物理学 · 物理学 2007-05-23 Patrick Boisse , Vincent Le Brun , Jacqueline Bergeron , Jean-Michel Deharveng

Peik and Tamm [Europhys. Lett. 61, 181 (2003)] proposed a nuclear clock based on the isomeric transition between the ground state and the first excited state of thorium-229. This transition was recognized as a potentially sensitive probe of…

原子物理 · 物理学 2021-01-19 Pavel Fadeev , Julian C. Berengut , Victor V. Flambaum

(abridged) We run a Faraday structure determination data challenge to benchmark the currently available algorithms including Faraday synthesis (previously called RM synthesis in the literature), wavelet, compressive sampling and…

We present late-time ($200-400$ days) near-infrared spectral evolution for the Type Ia supernova SN 2005df. The spectra show numerous strong emission features of [CoII], [CoIII], and [FeII] throughout the $0.8-1.8$\mu m region. As the…

太阳与恒星天体物理 · 物理学 2015-06-17 Tiara Diamond , Peter Hoeflich , Christopher L. Gerardy

The spatially resolved electrical transport properties have been studied on the surface of optimally-doped superconducting Ba(Fe1-xCox)2As2 single crystal by using a four-probe scanning tunneling microscopy. While some non-uniform contrast…

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…

天体物理学 · 物理学 2009-11-10 M. Dessauges-Zavadsky , C. Peroux , T. -S. Kim , S. D'Odorico , R. G. McMahon

Spectral differences between lensed quasar image components are common. Since lensing is intrinsically achromatic, these differences are typically explained as the effect of either microlensing, or as light path time delays sampling…

天体物理学 · 物理学 2009-11-11 Paul J. Green

We calculate sensitivity coefficients to $\alpha$-variation for the fine-structure transitions (1,0) and (2,1) within $^3P_J[2s^2 2p^2]$ multiplet of the Carbon-like ions C I, N II, O III, Na VI, Mg VII, and Si IX. These transitions lie in…

原子物理 · 物理学 2009-03-10 M. G. Kozlov , I. I. Tupitsyn , D. Reimers

Direction of arrival estimation (DoAE) aims at tracking a sound in azimuth and elevation. Recent advancements include data-driven models with inputs derived from ambisonics intensity vectors or correlations between channels in a microphone…

声音 · 计算机科学 2024-01-18 Adrian S. Roman , Iran R. Roman , Juan P. Bello

We present an improved determination of the proton structure functions $F_{2}$ and $xF_{3}$ from the CCFR $\nu $-Fe deep inelastic scattering (DIS) experiment. Comparisons to high-statistics charged-lepton scattering results for $F_{2}$…

高能物理 - 实验 · 物理学 2008-11-26 CCFR Collaboration , W. Seligman

We report on progress towards a measurement of the fine structure constant to an accuracy of $5\times 10^{-10}$ or better by measuring the ratio of the Planck constant to the mass of the cesium atom. Compared to similar experiments, ours is…

原子物理 · 物理学 2007-05-23 Holger Mueller , Sheng-wey Chiow , Quan Long , Christoph Vo , Steven Chu

One of the basic optoelectronic characteristics is the absorption of any optoelectronic device or material. We present the characteristics of pure GaAs and the deviation of ideal spectra. Due to crystal defects, vacancies, impurities, etc.,…

材料科学 · 物理学 2024-01-17 Subarna Alam , Mohammad Jahangir Alam

We explore the behaviour of [CII]-157.74um forbidden fine-structure line observed in a sample of 28 galaxies selected from ~50deg^2 of the H-ATLAS survey. The sample is restricted to galaxies with flux densities higher than S_160um>150mJy…

Measurements from the Gaia satellite have greatly increased our knowledge of the dark matter velocity distributions in the Solar neighborhood. There is evidence for multiple cold structures nearby, including a high-velocity stream…

高能物理 - 唯象学 · 物理学 2019-10-03 Matthew R. Buckley , Gopolang Mohlabeng , Christopher W. Murphy

We introduce a methodology to test models with spatial variations of the fine-structure constant $\alpha$, based on the calculation of the angular power spectrum of these measurements. This methodology enables comparisons of observations…

宇宙学与河外天体物理 · 物理学 2017-04-24 A. M. M. Pinho , M. Martinelli , C. J. A. P. Martins

Consider a two-class classification problem where we observe samples $(X_i, Y_i)$ for i = 1, ..., n, $X_i \in R^p$ and $Y_i$ in {0, 1}. Given $Y_i = k$, $X_i$ is assumed to follow a multivariate normal distribution with mean $\mu_k \in R^k$…

统计理论 · 数学 2023-02-23 Wanjie Wang , Jingjing Wu , Zhigang Yao

We examined the sizes of the absorption clouds in a z=1.3911 damped Ly-alpha absorber (DLA) in the double image lensed quasar Q0957+561 A,B (separation 135 pc at the absorber redshift). Using HIRES/Keck spectra, we studied the MgII…

天体物理学 · 物理学 2009-11-07 Chris Churchill , Rick Mellon , Jane Charlton , Steve Vogt

This study evaluates numerical discretization methods for the Single Particle Model (SPM) used in electrochemical modeling. The methods include the Finite Difference Method (FDM), spectral methods, Pad\'e approximation, and parabolic…

系统与控制 · 电气工程与系统科学 2025-06-03 Feng Guo , Luis D. Couto

We analyze the problem of quantum-limited estimation of a stochastically varying phase of a continuous beam (rather than a pulse) of the electromagnetic field. We consider both non-adaptive and adaptive measurements, and both dyne detection…

量子物理 · 物理学 2007-05-23 D. W. Berry , H. M. Wiseman
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