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Turbulent gas motions are expected to dominate the non-thermal energy budget of the intracluster medium (ICM). The measurement of pressure fluctuations from high angular resolution Sunyaev-Zel'dovich imaging opens a new avenue to study ICM…

The turbulent dynamics of nearby and extragalactic gas structures can be studied with the column density power spectrum, which is often described by a broken power-law.In an extragalactic context, the breaks in the power spectra have been…

Astrophysics of Galaxies · Physics 2021-06-09 Bastian Körtgen , Nickolas Pingel , Nicholas Killerby-Smith

We have developed a fast, accurate and generally applicable method for inferring the power spectrum and its uncertainties from maps of the cosmic microwave background (CMB) in the presence of inhomogeneous and correlated noise. For maps…

Astrophysics · Physics 2014-10-13 O. Doré , L. Knox , A. Peel

(Modified) The scaling of velocity fluctuation, dv, as a function of spatial scale L in molecular clouds can be measured from size-linewidth relations, principal component analysis, or line centroid variation. Differing values of the power…

Astrophysics · Physics 2009-11-10 C. M. Brunt , M. -M. Mac Low

The gas motions in the intracluster medium (ICM) are governed by stratified turbulence. Stratified turbulence is fundamentally different from Kolmogorov (isotropic, homogeneous) turbulence; kinetic energy not only cascades from large to…

Astrophysics of Galaxies · Physics 2020-03-26 Rajsekhar Mohapatra , Christoph Federrath , Prateek Sharma

Recent 21 cm radio observations of H$_I$ regions in the Small Magellanic Cloud, have revealed spatial power spectra of the intensity, which are quite similar in shape to those previously deduced for the Galaxy. The similarity, in spite the…

Astrophysics · Physics 2016-08-30 Itzhak Goldman

With the availability of galaxy distance indicators in weak lensing surveys, lensing tomography can be harnessed to constrain the three-dimensional (3D) matter power spectrum over a range of redshift and physical scale. By combining…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Patrick Simon

The APM Galaxy Survey maps the angular positions of more than one million galaxies to $b_{J} = 20$, covering a volume comparable to the forthcoming Sloan Digital Sky Survey. A numerical algorithm has been developed to estimate the power…

Astrophysics · Physics 2007-05-23 C. M. Baugh , E. Gaztanaga

The power spectrum of density fluctuations is a foundational source of cosmological information. Precision cosmological probes targeted primarily at investigations of dark energy require accurate theoretical determinations of the power…

Cosmology and Nongalactic Astrophysics · Physics 2010-08-26 Katrin Heitmann , David Higdon , Martin White , Salman Habib , Brian J. Williams , Christian Wagner

Estimation of the angular power spectrum of the Cosmic Microwave Background (CMB) on a small patch of sky is usually plagued by serious spectral leakage, specially when the map has a hard edge. Even on a full sky map, point source masks can…

Astrophysics · Physics 2009-11-06 Sudeep Das , Amir Hajian , David N. Spergel

We discuss various possibilities to constrain ICM turbulence in galaxy clusters using bright X-ray lines. Numerical simulations are used to find the most appropriate description of the 3D velocity field power spectrum (PDS) and to calibrate…

High Energy Astrophysical Phenomena · Physics 2011-01-26 I. Zhuravleva

Studies of surface brightness fluctuations in the intracluster medium (ICM) present an indirect probe of turbulent properties such as the turbulent velocities, injection scales, and the slope of the power spectrum of fluctuations towards…

Turbulence is a key element of the dynamics of astrophysical fluids, including those of interstellar medium, clusters of galaxies and circumstellar regions. Turbulent motions induce Doppler shifts of observable emission and absorption lines…

Astrophysics · Physics 2009-03-27 A. Chepurnov , A. Lazarian

The classification of galaxy clusters according to their X-ray appearance is a powerful tool to discriminate between regular clusters (associated to relaxed objects) and disturbed ones (linked to dynamically active systems). The compilation…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-29 Elena Rasia , Massimo Meneghetti , Stefano Ettori

With the steadily improving sensitivity afforded by current and future galaxy surveys, a robust extraction of two-point correlation function measurements may become increasingly hampered by the presence of astrophysical foregrounds or…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-21 Franz Elsner , Boris Leistedt , Hiranya V. Peiris

Mahdavi et al. find that the degree of agreement between weak lensing and X-ray mass measurements is a function of cluster radius. Numerical simulations also point out that X-ray mass proxies do not work equally well at all radii. The…

Cosmology and Nongalactic Astrophysics · Physics 2009-07-22 Yu-Ying Zhang , Thomas H Reiprich , Alexis Finoguenov , Daniel S. Hudson , Craig L Sarazin

We investigate the scale dependence of fluctuations inside a realistic model of an evolving turbulent HII region and to what extent these may be studied observationally. We find that the multiple scales of energy injection from champagne…

Astrophysics of Galaxies · Physics 2015-06-22 S. -N. X. Medina , S. J. Arthur , W. J. Henney , G. Mellema , A. Gazol

Using 3D high-resolution hydrodynamic simulations, tracking both electrons and ions, we study the effects of turbulence and conduction in the hot intracluster medium. We show how the power spectrum of the gas density perturbations can…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 M. Gaspari , E. Churazov

The statistical properties of a map of the primary fluctuations in the cosmic microwave background (CMB) may be specified to high accuracy by a few thousand power spectra measurements, provided the fluctuations are gaussian, yet the number…

Astrophysics · Physics 2009-11-07 Sujata Gupta , Alan F. Heavens

The power spectrum (PS) of mass density fluctuations, in the range $0.05 \leq k \leq 0.2 \ihmpc$, is derived from the Mark III catalog of peculiar velocities of galaxies, independent of ``biasing". It is computed from the density field as…

Astrophysics · Physics 2016-08-30 Tsafrir Kolatt , Avishai Dekel