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Related papers: A numerical twist on the observational spin parame…

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We propose a state estimation scheme for spins, using a modified setup of the Stern-Gerlach experiment, in which a beam of neutral spin-1/2 point particles interacts with a quadrupolar magnetic field. The proposed linear inversion…

Quantum Physics · Physics 2021-04-07 Javier Martínez-Cifuentes , K. M. Fonseca-Romero

By using a very simple and general model to describe the dynamics of disk galaxies, we estimate the $\lambda$ spin parameter for a sample of observed galaxies and present a study in which we show that several important physical properties…

Astrophysics · Physics 2008-10-06 B. Cervantes-Sodi , X. Hernandez

I present a discussion of fundamental stellar parameters and their observational determination in the context of interferometric measurements with current and future optical/infrared interferometric facilities. Stellar parameters and the…

Astrophysics · Physics 2007-05-23 M. Wittkowski

Weak lensing by large-scale structure is an invaluable cosmological tool given that most of the energy density of the concordance cosmology is invisible. Several large ground-based imaging surveys will attempt to measure this effect over…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-18 Eric M. Huff , Christopher M. Hirata , Rachel Mandelbaum , David Schlegel , Uros Seljak , Robert H. Lupton

Observing the Rossiter-McLaughlin effect during a planetary transit allows the determination of the angle $\lambda$ between the sky projections of the star's spin axis and the planet's orbital axis. Such observations have revealed a large…

Earth and Planetary Astrophysics · Physics 2021-10-04 Simon H. Albrecht , Marcus L. Marcussen , Joshua N. Winn , Rebekah I. Dawson , Emil Knudstrup

Tremaine and Weinberg (TW) proposed a conceptually simple procedure relying on long-slit spectroscopy to measure the pattern speeds of bars ($\Omega_{\rm p}$) in disk galaxies. Using a simulated galaxy, we investigate the potential biases…

Astrophysics of Galaxies · Physics 2019-10-16 Yanfei Zou , Juntai Shen , Martin Bureau , Zhao-Yu Li

Context. Large spectroscopic surveys open the way to explore our Galaxy. In order to use the data from these surveys to understand the Galactic stellar population, we need to be sure that stars contained in a survey are a representative…

Astrophysics of Galaxies · Physics 2018-12-26 Alexey Mints , Saskia Hekker

Extreme mass-ratio inspirals~(EMRIs) detectable by the Laser Inteferometric Space Antenna~(LISA) are unique probes of astrophysics and fundamental physics. Parameter estimation for these sources is challenging, especially because the…

General Relativity and Quantum Cosmology · Physics 2021-12-15 Gabriel Andres Piovano , Richard Brito , Andrea Maselli , Paolo Pani

The most direct way to confront observed galaxies with those formed in numerical simulations is to forward-model simulated galaxies into synthetic observations. Provided that synthetic galaxy observations include similar constraints and…

Astrophysics of Galaxies · Physics 2022-06-16 Connor Bottrell , Maan H. Hani

Accurate specification of a likelihood function is becoming increasingly difficult in many inference problems in astronomy. As sample sizes resulting from astronomical surveys continue to grow, deficiencies in the likelihood function lead…

Instrumentation and Methods for Astrophysics · Physics 2019-04-26 Jessi Cisewski-Kehe , Grant Weller , Chad Schafer

Precision weak gravitational lensing experiments require measurements of galaxy shapes accurate to <1 part in 1000. We investigate measurement biases, noted by Voigt and Bridle (2009) and Melchior et al. (2009), that are common to shape…

Instrumentation and Methods for Astrophysics · Physics 2015-05-18 Gary M. Bernstein

The existence of a kinematic morphology-density relation remains uncertain, and instead stellar mass appears the more dominant driver of galaxy kinematics. We investigate the dependence of the stellar spin parameter proxy $\lambda_{R_e}$ on…

We analyse the environmental properties of 370 local early-type galaxies (ETGs) in the MASSIVE and ATLAS3D surveys, two complementary volume-limited integral-field spectroscopic (IFS) galaxy surveys spanning absolute $K$-band magnitude…

Large scale correlations in the orientations of galaxies can result from alignments in their angular momentum vectors. These alignments arise from the tidal torques exerted on neighboring proto-galaxies by the smoothly varying shear field.…

Astrophysics · Physics 2009-07-09 Robert G. Crittenden , Priyamvada Natarajan , Ue-Li Pen , Tom Theuns

Knowledge of the scatter in the mass-observable relation is a key ingredient for a cosmological analysis based on galaxy clusters in a photometric survey. In this paper we aim to quantify the capability of the correlation function of galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-15 Julia Campa , Brenna Flaugher , Juan Estrada

Given a galaxy image, one cannot simply measure its flexion. An image's spin one and three shape properties, typically associated with F- and G-flexion, are actually complicated functions of the galaxy's intrinsic shape and the telescope's…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-26 Rebecca Sobel Levinson

Millisecond pulsars (MSPs) are spun up during their accretion phase in a binary system. The exchange of angular momentum between the accretion disk and the star tends to align the spin and orbital angular momenta on a very short time scale…

High Energy Astrophysical Phenomena · Physics 2026-03-25 Alexandra Lorange , Jérôme Pétri , Mattéo Sautron , Vincent Vigon

In a novel approach employing implicit likelihood inference (ILI), also known as likelihood-free inference, we calibrate the parameters of cosmological hydrodynamic simulations against observations, which has previously been unfeasible due…

Assuming General Relativity is correct on large-scales, Redshift-Space Distortions (RSDs) and the Integrated Sachs-Wolfe effect (ISW) are both sensitive to the time derivative of the linear growth function. We investigate the extent to…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Charles Shapiro , Robert G. Crittenden , Will J. Percival

We present new techniques to perform adaptive spatial binning of Integral-Field Spectroscopic (IFS) data to reach a chosen constant signal-to-noise ratio per bin. These methods are required for the proper analysis of IFS observations, but…

Astrophysics · Physics 2009-07-09 Michele Cappellari , Yannick Copin