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We report unbiased AI measurements of the fine structure constant $\alpha$ in two proximate absorption regions in the spectrum of the quasar HE0515$-$4414. The data are high resolution, high signal to noise, and laser frequency comb…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-18 John K. Webb , Chung-Chi Lee , Dinko Milakovic , Victor V. Flambaum , Vladimir A. Dzuba , Joao Magueijo

This paper addresses alternative procedures to the ESO supplied pipeline procedures for the reduction of UVES spectra of two quasar spectra to determine the value of the fundamental constant mu = Mp/Me at early times in the universe. The…

Astrophysics · Physics 2009-11-13 Rodger I. Thompson , Jill Bechtold , John H. Black , C. J. A. P. Martins

Recent advancements in quantum photonics have driven significant progress in photonic quantum computing (PQC), addressing challenges in scalability, efficiency, and fault tolerance. Experimental efforts have focused on integrated photonic…

Quantum Physics · Physics 2025-01-07 Dennis Delali Kwesi Wayo , Leonardo Goliatt , Darvish Ganji

Despite the dramatic progress made in neutrino oscillation studies recently, several fundamental neutrino parameters remain either unknown or poorly measured. We discuss in detail a method for their measurement by precision studies of…

High Energy Physics - Phenomenology · Physics 2008-11-08 Mikhail Batygov , Stephen Dye , John Learned , Shigenobu Matsuno , Sandip Pakvasa , Gary Varner

Despite being the most popular methods of data analysis, Fourier-based techniques suffer from the problem of static resolution that is currently believed to be a fundamental limitation of the Fourier Transform. Although alternative…

Data Analysis, Statistics and Probability · Physics 2008-06-04 Andrey Khilko

Quantum metrology derives its capabilities from the careful employ of quantum resources for carrying out measurements. This advantage, however, relies on refined data postprocessing, assessed based on the variance of the estimated…

Optimal error estimation is key to achieve accurate photometry and astrometry. Stellar fluxes and positions in high angular resolution images are typically measured with PSF fitting routines, such as StarFinder. However, the formal…

Instrumentation and Methods for Astrophysics · Physics 2022-08-12 E. Gallego-Cano , R. Schödel , A. T. Gallego-Calvente , A. M. Ghez

The resolution of separation of two elementary signals forming a partially coherent superposition, defined by quantum Fisher information and normalised with respect to detection probabilities, is always limited by the resolution of…

Quantum Physics · Physics 2021-03-15 Zdeněk Hradil , Dominik Koutný , Jaroslav Řeháček

A number of deep, wide-field, near-infrared surveys employing new infrared cameras on 4m-class telescopes are about to commence. These surveys have the potential to determine the fraction of luminous dust-obscured quasars that may have…

Astrophysics · Physics 2009-11-11 Natasha Maddox , Paul C. Hewett

We describe the results of a search for time variability of the fine structure constant, alpha, using absorption systems in the spectra of distant quasars. Three large optical datasets and two 21cm/mm absorption systems provide four…

Recent quasar spectroscopy from the VLT and Keck telescopes suggests that fundamental constants may not actually be constant. To better confirm or refute this result, systematic errors between telescopes must be minimized. We present a new…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Tyler M. Evans , Michael T. Murphy

Even though measurement results obtained in the real world are generally both noisy and continuous, quantum measurement theory tends to emphasize the ideal limit of perfect precision and quantized measurement results. In this article, a…

Quantum Physics · Physics 2008-12-18 Holger F. Hofmann

Superresolution theory and techniques seek to recover signals from samples in the presence of blur and noise. Discrete image registration can be an approach to fuse information from different sets of samples of the same signal. Quantization…

Computer Vision and Pattern Recognition · Computer Science 2024-12-16 Serap A. Savari

Measuring the centroid of a spectral line is a common problem in astronomy. Many methods have been devised to overcome limitations due to either noise in the spectra or asymmetric profiles, the most common of which are the intensity…

Instrumentation and Methods for Astrophysics · Physics 2018-09-28 Richard Teague , Daniel Foreman-Mackey

Calculation of the Dirac hydrogen atom spectrum in the framework of dynamical fine structure constant (alpha) variability discloses a small departure in the laboratory from Sommerfeld's formula for the fine structure shifts, possibly…

Astrophysics · Physics 2007-05-23 Jacob D. Bekenstein

Sample selection is a necessary preparation for weak lensing measurement. It is well-known that selection itself may introduce bias in the measured shear signal. Using image simulation and the Fourier_Quad shear measurement pipeline, we…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-04 Hekun Li , Jun Zhang , Dezi Liu , Wentao Luo , Jiajun Zhang , Fuyu Dong , Zhi Shen , Haoran Wang

The wavelength calibration of spectrographs is an essential but challenging task in many disciplines. Calibration is traditionally accomplished by imaging the spectrum of a light source containing features that are known to appear at…

Instrumentation and Methods for Astrophysics · Physics 2018-04-04 Neil Thomas

A software product line models the variability of highly configurable systems. Complete exploration of all valid configurations (the configuration space) is infeasible as it grows exponentially with the number of features in the worst case.…

Quantum Physics · Physics 2023-07-28 Joshua Ammermann , Tim Bittner , Domenik Eichhorn , Ina Schaefer , Christoph Seidl

We introduce a technique to measure gravitational lensing magnification using the variability of type I quasars. Quasars' variability amplitudes and luminosities are tightly correlated, on average. Magnification due to gravitational lensing…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Anne H. Bauer , Stella Seitz , Jonathan Jerke , Richard Scalzo , David Rabinowitz , Nancy Ellman , Charles Baltay

Bicoherence analysis is a well established method for identifying the quadratic nonlinearity of stationary processes. However, it is often applied without checking the basic assumptions of stationarity and convergence. The classic…

Signal Processing · Electrical Eng. & Systems 2018-11-08 Peter Zsolt Poloskei , Gergely Papp , Gabor Por , Laszlo Horvath , Gergo I. Pokol
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