Lagrangian approach to super-sample effects on biased tracers at field level: galaxy density fields and intrinsic alignments

Abstract It has been recognized that the observables of large-scale structure (LSS) is susceptible to long-wavelength density and tidal fluctuations whose wavelengths exceed the accessible scale of a finite-volume observation, referred to as the super-sample modes. The super-sample modes modulate the growth and expansion rate of local structures, thus affecting the cosmological information encoded in the statistics of galaxy clustering data. In this paper, based on the Lagrangian perturbation theory, we develop a new formalism to systematically compute the response of a biased tracer of LSS, which is expressed perturbatively in terms of the matter density field of sub-survey modes, to the super-sample modes at the field level. The formalism presented here reproduces the power spectrum responses that have been previously derived, and provides an alternative way to compute statistical quantities with super-sample modes. As an application, we consider the statistics of the intrinsic alignments of galaxies and halos, and derive the field response of the galaxy/halo shape bias to the super-sample modes. Possible impacts of the long-mode contributions on the covariance of the three-dimensional power spectra of the intrinsic alignment are also discussed, and the signal-to-noise ratios are estimated.

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Simulations of the star-forming molecular gas in an interacting M51-like galaxy

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz3600 ◽

2020 ◽

Vol 492 (2) ◽

pp. 2973-2995 ◽

Cited By ~ 11

Author(s):

Robin G Tress ◽

Rowan J Smith ◽

Mattia C Sormani ◽

Simon C O Glover ◽

Ralf S Klessen ◽

...

Keyword(s):

Star Formation ◽

Large Scale ◽

Formation Rate ◽

Three Dimensional ◽

Molecular Gas ◽

Secondary Importance ◽

Star Forming ◽

The Galaxy ◽

Cold Star ◽

Self Gravity

ABSTRACT We present here the first of a series of papers aimed at better understanding the evolution and properties of giant molecular clouds (GMCs) in a galactic context. We perform high-resolution, three-dimensional arepo simulations of an interacting galaxy inspired by the well-observed M51 galaxy. Our fiducial simulations include a non-equilibrium, time-dependent, chemical network that follows the evolution of atomic and molecular hydrogen as well as carbon and oxygen self-consistently. Our calculations also treat gas self-gravity and subsequent star formation (described by sink particles), and coupled supernova feedback. In the densest parts of the simulated interstellar medium (ISM), we reach sub-parsec resolution, granting us the ability to resolve individual GMCs and their formation and destruction self-consistently throughout the galaxy. In this initial work, we focus on the general properties of the ISM with a particular focus on the cold star-forming gas. We discuss the role of the interaction with the companion galaxy in generating cold molecular gas and controlling stellar birth. We find that while the interaction drives large-scale gas flows and induces spiral arms in the galaxy, it is of secondary importance in determining gas fractions in the different ISM phases and the overall star formation rate. The behaviour of the gas on small GMC scales instead is mostly controlled by the self-regulating property of the ISM driven by coupled feedback.

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Three-dimensional Visualization of Cosmological and Galaxy Formation Simulations

Proceedings of the International Astronomical Union ◽

10.1017/s1743921311022915 ◽

2010 ◽

Vol 6 (S277) ◽

pp. 263-266

Author(s):

Bruno Thooris ◽

Daniel Pomarède

Keyword(s):

Galaxy Formation ◽

Adaptive Mesh Refinement ◽

Large Scale ◽

Multiple Scales ◽

Three Dimensional ◽

Adaptive Mesh ◽

Ray Casting ◽

Parallel Simulations ◽

The Galaxy ◽

Isosurface Reconstruction

AbstractOur understanding of the structuring of the Universe from large-scale cosmological structures down to the formation of galaxies now largely benefits from numerical simulations. The RAMSES code, relying on the Adaptive Mesh Refinement technique, is used to perform massively parallel simulations at multiple scales. The interactive, immersive, three-dimensional visualization of such complex simulations is a challenge that is addressed using the SDvision software package. Several rendering techniques are available, including ray-casting and isosurface reconstruction, to explore the simulated volumes at various resolution levels and construct temporal sequences. These techniques are illustrated in the context of different classes of simulations. We first report on the visualization of the HORIZON Galaxy Formation Simulation at MareNostrum, a cosmological simulation with detailed physics at work in the galaxy formation process. We then carry on in the context of an intermediate zoom simulation leading to the formation of a Milky-Way like galaxy. Finally, we present a variety of simulations of interacting galaxies, including a case-study of the Antennae Galaxies interaction.

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Quantifying EoR delay spectrum contamination from diffuse radio emission

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa987 ◽

2020 ◽

Vol 494 (3) ◽

pp. 3712-3727 ◽

Cited By ~ 1

Author(s):

Adam E Lanman ◽

Jonathan C Pober ◽

Nicholas S Kern ◽

Eloy de Lera Acedo ◽

David R DeBoer ◽

...

Keyword(s):

Radio Emission ◽

Large Scale ◽

Power Spectra ◽

Neutral Hydrogen ◽

Spectral Structure ◽

Wide Field ◽

Electromagnetic Simulations ◽

The Galaxy ◽

Spectral Weighting ◽

The Universe

ABSTRACT The 21 cm hyperfine transition of neutral hydrogen offers a promising probe of the large-scale structure of the universe before and during the Epoch of Reionization (EoR), when the first ionizing sources formed. Bright radio emission from foreground sources remains the biggest obstacle to detecting the faint 21 cm signal. However, the expected smoothness of foreground power leaves a clean window in Fourier space where the EoR signal can potentially be seen over thermal noise. Though the boundary of this window is well defined in principle, spectral structure in foreground sources, instrumental chromaticity, and choice of spectral weighting in analysis all affect how much foreground power spills over into the EoR window. In this paper, we run a suite of numerical simulations of wide-field visibility measurements, with a variety of diffuse foreground models and instrument configurations, and measure the extent of contaminated Fourier modes in the EoR window using a delay-transform approach to estimate power spectra. We also test these effects with a model of the Hydrogen Epoch of Reionization Array (HERA) antenna beam generated from electromagnetic simulations, to take into account further chromatic effects in the real instrument. We find that foreground power spillover is dominated by the so-called pitchfork effect, in which diffuse foreground power is brightened near the horizon due to the shortening of baselines. As a result, the extent of contaminated modes in the EoR window is largely constant over time, except when the Galaxy is near the pointing centre.

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Mapping the three-dimensional multi-band extinction and diffuse interstellar bands in the Milky Way with LAMOST

Proceedings of the International Astronomical Union ◽

10.1017/s174392131300642x ◽

2013 ◽

Vol 9 (S298) ◽

pp. 240-245 ◽

Cited By ~ 1

Author(s):

H.-B. Yuan ◽

X.-W. Liu ◽

M.-S Xiang ◽

Z.-Y. Huo ◽

H.-H. Zhang ◽

...

Keyword(s):

Large Scale ◽

Three Dimensional ◽

Wide Field ◽

Stellar Spectra ◽

Photometric Calibration ◽

Diffuse Interstellar Bands ◽

The Galaxy ◽

Spectroscopic Database ◽

Galactic Astronomy ◽

Multi Band

AbstractWith modern large scale spectroscopic surveys, such as the SDSS and LSS-GAC, Galactic astronomy has entered the era of millions of stellar spectra. Taking advantage of the huge spectroscopic database, we propose to use a “standard pair" technique to a) Estimate multi-band extinction towards sightlines of millions of stars; b) Detect and measure the diffuse interstellar bands in hundreds of thousands SDSS and LAMOST low-resolution spectra; c) Search for extremely faint emission line nebulae in the Galaxy; and d) Perform photometric calibration for wide field imaging surveys. In this contribution, we present some results of applying this technique to the SDSS data, and report preliminary results from the LAMOST data.

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Power spectrum of halo intrinsic alignments in simulations

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa3625 ◽

2020 ◽

Vol 501 (1) ◽

pp. 833-852

Author(s):

Toshiki Kurita ◽

Masahiro Takada ◽

Takahiro Nishimichi ◽

Ryuichi Takahashi ◽

Ken Osato ◽

...

Keyword(s):

Power Spectrum ◽

Large Scale ◽

Signal To Noise Ratio ◽

Cosmological Parameters ◽

Three Dimensional ◽

Power Spectra ◽

Acoustic Oscillations ◽

Matter Power Spectrum ◽

Sample Covariance ◽

Non Linear

ABSTRACT We use a suite of N-body simulations to study intrinsic alignments (IA) of halo shapes with the surrounding large-scale structure in the ΛCDM model. For this purpose, we develop a novel method to measure multipole moments of the three-dimensional power spectrum of the E-mode field of halo shapes with the matter/halo distribution, $P_{\delta E}^{(\ell)}(k)$ (or $P^{(\ell)}_{{\rm h}E}$), and those of the auto-power spectrum of the E-mode, $P^{(\ell)}_{EE}(k)$, based on the E/B-mode decomposition. The IA power spectra have non-vanishing amplitudes over the linear to non-linear scales, and the large-scale amplitudes at k ≲ 0.1 h−1 Mpc are related to the matter power spectrum via a constant coefficient (AIA), similar to the linear bias parameter of galaxy or halo density field. We find that the cross- and auto-power spectra PδE and PEE at non-linear scales, k ≳ 0.1 h−1 Mpc, show different k-dependences relative to the matter power spectrum, suggesting a violation of the non-linear alignment model commonly used to model contaminations of cosmic shear signals. The IA power spectra exhibit baryon acoustic oscillations, and vary with halo samples of different masses, redshifts, and cosmological parameters (Ωm, S8). The cumulative signal-to-noise ratio for the IA power spectra is about 60 per cent of that for the halo density power spectrum, where the super-sample covariance is found to give a significant contribution to the total covariance. Thus our results demonstrate that the IA power spectra of galaxy shapes, measured from imaging and spectroscopic surveys for an overlapping area of the sky, can be used to probe the underlying matter power spectrum, the primordial curvature perturbations, and cosmological parameters, in addition to the standard galaxy density power spectrum.

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Low-frequency measurements of synchrotron absorbing HII regions and modeling of observed synchrotron emissivity

Astronomy and Astrophysics ◽

10.1051/0004-6361/201834405 ◽

2019 ◽

Vol 621 ◽

pp. A127 ◽

Cited By ~ 2

Author(s):

I. M. Polderman ◽

M. Haverkorn ◽

T. R. Jaffe ◽

M. I. R. Alves

Keyword(s):

Synchrotron Radiation ◽

Magnetic Fields ◽

Large Scale ◽

Milky Way ◽

Galactic Center ◽

Three Dimensional ◽

Low Frequency ◽

Hii Regions ◽

The Galaxy ◽

Absorption Measurements

Context. Cosmic rays (CRs) and magnetic fields are dynamically important components in the Galaxy, and their energy densities are comparable to that of the turbulent interstellar gas. The interaction of CRs and Galactic magnetic fields (GMF) produces synchrotron radiation clearly visible in the radio regime. Detailed measurements of synchrotron radiation averaged over the line-of-sight (LOS), so-called synchrotron emissivities, can be used as a tracer of the CR density and GMF strength. Aims. Our aim is to model the synchrotron emissivity in the Milky Way using a three-dimensional dataset instead of LOS-integrated intensity maps on the sky. Methods. Using absorbed HII regions, we measured the synchrotron emissivity over a part of the LOS through the Galaxy, changing from a two-dimensional to a three-dimensional view. Performing these measurements on a large scale is one of the new applications of the window opened by current low-frequency arrays. Using various simple axisymmetric emissivity models and a number of GMF-based emissivity models, we were able to simulate the synchrotron emissivities and compare them to the observed values in the catalog. Results. We present a catalog of low-frequency absorption measurements of HII regions, their distances and electron temperatures, compiled from literature. These data show that the axisymmetric emissivity models are not complex enough, but the GMF-based emissivity models deliver a reasonable fit. These models suggest that the fit can be improved by either an enhanced synchrotron emissivity in the outer reaches of the Milky Way or an emissivity drop near the Galactic center. Conclusions. Current GMF models plus a constant CR density model cannot explain low-frequency absorption measurements, but the fits improved with slight (ad hoc) adaptations. It is clear that more detailed models are needed, but the current results are very promising.

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Infrared Background Starlight: Observations and Galaxy Models

Symposium - International Astronomical Union ◽

10.1017/s0074180900240382 ◽

1990 ◽

Vol 139 ◽

pp. 35-47

Author(s):

G. G. Fazio ◽

T. M. Dame ◽

S. Kent

Keyword(s):

Large Scale ◽

Near Infrared ◽

Galactic Disk ◽

Dust Emission ◽

Three Dimensional ◽

Infrared Region ◽

Global Scale ◽

Three Dimensional Model ◽

Infrared Telescope ◽

The Galaxy

The near-infrared region of the spectrum is a particularly advantageous window for observing the distribution of old, evolved stars in the galactic disk and bulge. These stars are important because they provide an excellent tracer of the overall stellar mass distribution. At shorter wavelengths extinction is a serious problem, and at longer wavelengths the flux is dominated by dust emission. A summary of the large-scale diffuse near-infrared observations of the Galaxy is presented, as is a summary of the results obtained from these data on the structure of the galactic disk and bulge. The importance of combining CO and near-infrared maps of similar resolution to determine a three-dimensional model of galactic extinction is demonstrated. The Spacelab-2 Infrared Telescope (IRT) data are used in conjunction with a proposed galactic model to make preliminary measurements of the global scale parameters of the Galaxy.

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Detecting multi-scale filaments in galaxy distribution

Proceedings of the International Astronomical Union ◽

10.1017/s1743921314010680 ◽

2014 ◽

Vol 10 (S306) ◽

pp. 45-47

Author(s):

Elmo Tempel

Keyword(s):

Point Process ◽

Large Scale ◽

Three Dimensional ◽

Sloan Digital Sky Survey ◽

Point Distribution ◽

Multi Scale ◽

Galaxy Distribution ◽

Sky Survey ◽

The Galaxy ◽

Redshift Survey

AbstractThe main feature of the spatial large-scale galaxy distribution is its intricate network of galaxy filaments. This network is spanned by the galaxy locations that can be interpreted as a three-dimensional point distribution. The global properties of the point process can be measured by different statistical methods, which, however, do not describe directly the structure elements. The morphology of the large-scale structure, on the other hand, is an important property of the galaxy distribution. Here, we apply an object point process with interactions (the Bisous model) to trace and extract the filamentary network in the presently largest galaxy redshift survey, the Sloan Digital Sky Survey (SDSS data release 10). We search for multi-scale filaments in the galaxy distribution that have a radius of about 0.5, 1.0, 2.0, and 4.0h−1Mpc. We extract the spines of the filamentary network and divide the detected network into single filaments.

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Experimental Study on Seismic Responses of Piping Systems With Friction—Part 1: Large-Scale Shaking Table Vibration Test

Journal of Pressure Vessel Technology ◽

10.1115/1.2842118 ◽

1995 ◽

Vol 117 (3) ◽

pp. 245-249 ◽

Cited By ~ 3

Author(s):

K. Suzuki ◽

T. Watanabe ◽

T. Mitsumori ◽

N. Shimizu ◽

H. Kobayashi ◽

...

Keyword(s):

Experimental Study ◽

Large Scale ◽

Earth Science ◽

Three Dimensional ◽

Power Spectra ◽

Reduction Factor ◽

Oil Refinery ◽

Shaking Table ◽

Piping Systems ◽

Frictional Vibration

This report deals with the experimental study of seismic response behavior of piping systems in industrial facilities such as petrochemical, oil refinery, and nuclear plants. Special attention is focused on the nonlinear dynamic response of piping systems due to frictional vibration appearing in piping and supporting devices. A three-dimensional mock-up piping and supporting structure model wherein piping is of 30-m length and 200-mm diameter is excited by a large-scale (15 m × 15 m) shaking table belonging to the National Research Institute for Earth Science and Disaster Prevention in Tsukuba, Ibaraki. Power spectra of the response vibration and the loading-response relationship in the form of a hysteresis loop under several loading conditions are obtained. The response reduction effect caused by frictional vibration is evaluated and demonstrated in terms of “response reduction factor.”

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