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We investigate the variation of the fine-structure constant, {\alpha}, in symmetron models using N-body simulations in which the full spatial distribution of {\alpha} at different redshifts has been calculated. In particular, we obtain…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-29 Marvin F. Silva , Hans A. Winther , David F. Mota , C. J. A. P. Martins

New results on diffractive deep-inelastic $e p$ scattering at HERA are presented using data taken in 1994 with the H1 detector. The cross section for diffractive deep-inelastic scattering is measured in terms of a diffractive structure…

High Energy Physics - Experiment · Physics 2007-05-23 S. Tapprogge

We investigate the prospects for constraining the maximum scale of clumping in composition that is consistent with observed Type Ia supernova flux spectra. Synthetic spectra generated without purely spherical composition symmetry indicate…

Astrophysics · Physics 2009-11-06 R. C. Thomas , Daniel Kasen , David Branch , E. Baron

This manuscript presents a data-processing technique which improves the accuracy and precision of absorption-spectroscopy measurements by isolating the molecular absorbance signal from errors in the baseline light intensity (Io) using…

Instrumentation and Detectors · Physics 2020-09-24 Christopher S. Goldenstein , Garrett C. Mathews , Ryan K. Cole , Amanda S. Makowiecki , Gregory B. Rieker

We monitored five high-luminosity quasars with lambda L_{3000A} > 10^45 erg s^-1 at 0.4 < z < 0.6 to measure flux variability of the MgII 2798 line and explore feasibility of reverberation mapping using MgII. Over the two year monitoring…

Astrophysics · Physics 2009-11-13 Jong-Hak Woo

Sensitivity to temporal variation of the fundamental constants may be strongly enhanced in transitions between narrow close levels of different nature. This enhancement may be realized in a large number of molecules due to cancelation…

Atomic Physics · Physics 2008-11-26 V. V. Flambaum , M. G. Kozlov

Studying the stellar mass, age, luminosity, star-formation rate, and impact parameter of quasar absorber host galaxies can aid in the understanding of galaxy formation and evolution as well as in testing their models. We derive the Spectral…

Astrophysics of Galaxies · Physics 2018-09-12 Bill Zhu , Yinan Zhao , Jian Ge , Jingzhe Ma

Purpose: To describe the dosimetric commissioning and quality assurance (QA) of the actively scanned proton and carbon ion beams at the Italian National Center for Oncological Hadrontherapy. Methods: The laterally integrated…

The comparison of different atomic transition frequencies over time can be used to determine the present value of the temporal derivative of the fine structure constant alpha in a model-independent way without assumptions on constancy or…

Atomic Physics · Physics 2009-11-10 E. Peik , B. Lipphardt , H. Schnatz , T. Schneider , Chr. Tamm , S. G. Karshenboim

The spectrum of singly-ionized iron (Fe II) has been recorded using high-resolution Fourier transform and grating spectroscopy over the wavelength range 900 {\AA} to 5.5 {\mu}m. The spectra were observed in high-current continuous and…

Instrumentation and Methods for Astrophysics · Physics 2015-03-13 Gillian Nave , Sveneric Johansson

Many modern theories predict that the fundamental constants depend on time, position, or the local density of matter. We develop a spectroscopic method for pulsed beams of cold molecules, and use it to measure the frequencies of microwave…

We analyze high-resolution spectra obtained with the Space Telescope Imaging Spectrograph onboard the Hubble Space Telescope toward 34 nearby stars (<100 pc) to record MgII, FeII and MnII absorption due to the local interstellar medium…

Solar and Stellar Astrophysics · Physics 2015-06-19 Craig Malamut , Seth Redfield , Jeffrey L. Linsky , Brian E. Wood , Thomas R. Ayres

We investigate the dependence on data quality of quasar properties measured from the CIV emission line region at high redshifts. Our measurements come from 32 epochs of Sloan Digital Sky Survey (SDSS) Reverberation Mapping Project…

Astrophysics of Galaxies · Physics 2016-06-08 K. D. Denney , Keith Horne , W. N. Brandt , Luis C. Ho , B. M. Peterson , Gordon T. Richards , Yue Shen , J. R. Trump , J. Ge

A study of the absorption systems toward the gravitationally lensed quasar APM 08279+5255 is presented. Most of the MgII systems in the redshift range 1.2-2.07, although saturated, show large residuals at the bottom of the lines. The most…

Astrophysics · Physics 2007-05-23 Patrick Petitjean , Bastien Aracil , R. Srianand , Rodrigo Ibata

It has been proposed that the radio-frequency electric-dipole (E1) transition between two nearly degenerate opposite-parity states in atomic dysprosium should be highly sensitive to possible temporal variation of the fine structure constant…

Atomic Physics · Physics 2009-11-10 A. T. Nguyen , D. Budker , S. K. Lamoreaux , J. R. Torgerson

We review and compare the reconstruction methods of the inclusive deep inelastic scattering variables used at HERA. We introduce a new prescription, the $\Sigma$ method, which allows to measure the structure function of the proton…

High Energy Physics - Experiment · Physics 2009-10-22 Ursula Bassler , Gregorio Bernardi

Considering the increasing number of experimental results in the manufacturing process of quantum dots with different geometries, and the fact that most numerical methods that can be used to investigate quantum dots with non-trivial…

Materials Science · Physics 2022-12-06 G. A. Mantashian , P. A. Mantashyan , D. B. Hayrapetyan

The DAMA/LIBRA collaboration has detected an annual modulation of the recoil rate in NaI crystals with the phase expected for WIMP scattering events. This signal is dramatically inconsistent with upper limits from other experiments for…

Cosmology and Nongalactic Astrophysics · Physics 2010-09-14 Douglas P. Finkbeiner , Tongyan Lin , Neal Weiner

Probabilistic shaping of quadrature amplitude modulation (QAM) is used to enhance the sensitivity of an optical communication system. Sensitivity gains of 0.43 dB and 0.8 dB are demonstrated in back-to-back experiments by shaping of 16QAM…

Information Theory · Computer Science 2016-01-19 Tobias Fehenberger , Domaniç Lavery , Robert Maher , Alex Alvarado , Polina Bayvel , Norbert Hanik

Over a period of eight months, we have monitored transition frequencies between nearly degenerate, opposite-parity levels in two isotopes of atomic dysprosium (Dy). These transition frequencies are highly sensitive to temporal variation of…

Atomic Physics · Physics 2008-11-26 A. Cingoz , A. Lapierre , A. -T. Nguyen , N. Leefer , D. Budker , S. K. Lamoreaux , J. R. Torgerson