English
Related papers

Related papers: Where are the Baryons?

200 papers

We investigate the baryon content of the circumgalactic medium (CGM) within the virial radius of $M_h \sim 10^{12} \; M_\odot$ haloes at z ~ 3, by modelling the surface brightness profile of the giant Ly$\alpha$ nebulae recently discovered…

Astrophysics of Galaxies · Physics 2019-04-15 Gabriele Pezzulli , Sebastiano Cantalupo

The cosmic ultraviolet background (UVB) heats the intergalactic medium (IGM), as a result the gas in dark matter halos below a certain mass is too hot to cool within a Hubble time. The UVB effectively suppresses the formation of dwarf…

Astrophysics · Physics 2009-11-13 Matthias Hoeft , Gustavo Yepes , Stefan Gottloeber

The amount of detected baryons in the local Universe is at least a factor of two smaller than measured at high redshift. It is believed that a significant fraction of the baryons in the current Universe is "hiding" in a hot filamentary…

Astrophysics · Physics 2014-11-18 M. Galeazzi , A. Gupta , E. Ursino

We compute, including a current state-of-the-art treatment of hydrodynamical processes, heating and cooling, a variety of cosmological models into the extreme nonlinear phase to enable comparisons with observations. First, we note the…

Astrophysics · Physics 2009-10-28 Jeremiah P. Ostriker , Renyue Cen

Numerical simulations of the intergalactic medium have shown that at the present epoch a significant fraction (40-50%) of the baryonic component should be found in the (T~10^6K) Warm-Hot Intergalactic Medium (WHIM) - with several recent…

Astrophysics · Physics 2008-11-26 Renyue Cen , Taotao Fang

We investigate a sample of 14 clusters of galaxies observed with XMM-Newton in a search for soft X-ray excess emission. In five of these clusters a significant soft excess is evident. This soft X-ray excess is compared with the thermal…

Astrophysics · Physics 2009-11-07 J. S. Kaastra , R. Lieu , T. Tamura , F. B. S. Paerels , J. W. den Herder

Today, the majority of the cosmic baryons in the Universe are not observed directly, leading to an issue of "missing baryons" at low redshift. Cosmological hydrodynamical simulations have indicated that a significant portion of them will be…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-07 A. Fresco , C. Péroux , A. Merloni , A. Hamanowicz , R. Szakacs

We derive analytic lower bounds on the cosmic baryon density by requiring that the high-redshift IGM contain enough neutral hydrogen to produce the observed \lya absorption in quasar spectra. The key theoretical assumption is that absorbing…

Astrophysics · Physics 2009-10-30 David H. Weinberg , Jordi Miralda-Escude , Lars Hernquist , Neal Katz

Various independent ways of constraining the Hubble constant and the baryonic content of the universe finally converged at a consensus range of values which indicates that at the present epoch the bulk of the universe's baryons is in the…

Astrophysics · Physics 2007-05-23 Richard Lieu , Massimiliano Bonamente , Jonathan P. D. Mittaz

The Milky Way appears to be missing baryons, as the observed mass in stars and gas is well below the cosmic mean. One possibility is that a substantial fraction of the Galaxy's baryons are embedded within an extended, million-degree hot…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Taotao Fang , James S. Bullock , Michael Boylan-Kolchin

We investigate the baryon fraction in dark matter haloes formed in non-radiative gas-dynamical simulations of the LambdaCDM cosmogony. By combining a realisation of the Millennium Simulation (Springel et al.) with a simulation of a smaller…

Recent observations with SRG/eROSITA have revealed the average X-ray surface brightness profile of the X-ray-emitting circumgalactic medium (CGM) around Milky Way (MW)-mass galaxies, offering valuable insights into the baryon mass in these…

Galaxy groups are the least massive systems where the bulk of baryons begin to be accounted for. Not simply the scaled-down versions of rich clusters following self-similar relations, galaxy groups are ideal systems to study baryon physics,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Ming Sun

Traditionally, galaxy clusters have been expected to retain all the material accreted since their formation epoch. For this reason, their matter content should be representative of the Universe as a whole, and thus their baryon fraction…

We present the analysis of baryonic and non-baryonic matter distribution in a sample of ten nearby clusters ($0.03<z<0.09$) with temperatures between 4.7 and 9.4 keV. These galaxy clusters have been studied in detail using X-ray data and…

Astrophysics · Physics 2007-05-23 Africa Castillo-Morales , Sabine Schindler

The Hot Universe Baryon Surveyor (HUBS) mission is proposed to study "missing" baryons in the universe. Unlike dark matter, baryonic matter is made of elements in the periodic table, and can be directly observed through the electromagnetic…

Instrumentation and Methods for Astrophysics · Physics 2021-01-15 Wei Cui

We use numerical simulations of structure formation in a Cold Dark Matter model to predict the absorption lines in the soft X-rays produced by heavy elements in the shock-heated intergalactic medium at low redshift. The simulation…

Astrophysics · Physics 2009-10-30 Uffe Hellsten , Nickolay Y. Gnedin , Jordi Miralda-Escude

Quasar absorption lines now permit a direct probe of deuterium abundances in primordial material, with the best current estimate $ (D/H)=1.9\pm 0.4 \times 10^{-4}$. If this is the universal primordial abundance $(D/H)_p$, Standard Big Bang…

Astrophysics · Physics 2008-02-03 Craig J. Hogan

At least 50% of the baryons in the local universe are undetected and predicted to be in a hot dilute phase (1E5-1E7 K) in low and moderate overdensity environments. We searched for the predicted diffuse faint emission through shadowing…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-30 Joel N. Bregman , Birgit Otte , Jimmy A. Irwin , Mary E. Putman , Edward J. Lloyd-Davies , Christian Brüns

We present measurements of the Galactic halo's X-ray emission for 110 XMM-Newton sight lines, selected to minimize contamination from solar wind charge exchange emission. We detect emission from few million degree gas on ~4/5 of our sight…

Astrophysics of Galaxies · Physics 2015-06-16 David B. Henley , Robin L. Shelton