helium sedimentation primordial

Revisiting ΔY/ΔZ from multiple main sequences in globular ...

HB stars in the (narrow but crucial) temperature range For diffusion in particular, observations of field and cluster 8500 < Teff < 11500, hot enough to produce helium lines metalpoor dwarfs point toward inhibited efficiency and ad but still unaffected by helium sedimentation.

Big Bang nucleosynthesis Wikipedia

Primordial nucleosynthesis is believed by most cosmologists to have taken place in the interval from roughly 10 seconds to 20 minutes after the Big Bang, and is calculated to be responsible for the formation of most of the universe's helium as the isotope helium4 (4 He), along with small amounts of the hydrogen isotope deuterium (2 H or D ...

Helium isotopes, tectonics and heat flow in the Northern ...

Helium isotopes, tectonics and heat flow in the Northern Caucasus. ... enhanced 3 He/ 4 He ratios in a conservative way as those resulting from mixing of crustal radiogenic and mantle partially primordial helium. ... climatic changes, groundwater circulation, variability of thermal properties of rocks, sedimentation, thrusting, etc.).

The Origin of Oil—A Creationist Answer | Answers in Genesis

Dec 17, 2008· There is associated helium (up to 10% in some U. S. reservoirs) alongside the hydrocarbons. ... this is a contradiction that the sedimentation took place in seawater that had had plenty of time to approach near equilibrium. ... the primordial repositories containing the hydrocarbons will have been breached and fluids released ...

arXiv: [] 20 Oct 2009

HELIUM SEDIMENTATION AND THE ULTRAVIOLET UPTURN IN BRIGHTEST CLUSTER GALAXIES FangPeng1, ... sedimentation velocity of He nuclei as wHe = 3mpgnHe/KpHe, which gives wHe ≃ 80kms−1 T 10keV 3/2 g ... Y0 is the primordial He mass fraction and τ ...

HELIUM SEDIMENTATION AND THE ULTRAVIOLET UPTURN …

No. 1, 2009 HELIUM SEDIMENTATION AND THE UV UPTURN L59 forces acting on a specie s, and it is the balance of these forces that ultimately determines the rate of sedimentation. For a sinking He nucleus, the gravitational force (g) is counteracted by ... 0 is the primordial

Gravitational diffusion in the intracluster medium ...

The assumed helium sedimentation model, on average, produces a negligible increase in the gas mass inferred within large radii (r < r500) ( +/ per cent) and a ( +/ ) per cent mean ...

Primordial Helium, Created in Big Bang, Detected at Long ...

Jun 13, 1995· A version of this article appears in print on June 13, 1995, on Page C00001 of the National edition with the headline: Primordial Helium, Created in Big Bang, Detected at Long Last.

geochemistry Are fossil fuels really formed from fossils ...

Are fossil fuels really formed from fossils? Ask Question 1 \begingroup ... Primordial hydrocarbons are still upwelling from the deep earth. ... It more adequately explains why Helium is only present in the earth at any mineable quantity in natural gas.

Primordial Helium Abundance and the Primordial Fireball. II

Primordial Helium Abundance and the Primordial Fireball. II Peebles Palmer Physical Laboratory, Princeton University, 1966 ... is the primordial fireball, the radiation left over from ... Helium formation at t=1s when we had a temperature T~10 10 K With (mn –mp)c 2 ~ p , ...

Helium abundance in galaxy clusters and SunyaevZeldovich ...

Helium abundance in galaxy clusters and SunyaevZeldovich effect. ... The assumed helium sedimentation model, on average, produces a negligible increase in …

Helium Isotopes | SpringerLink

This component was well identified in deep sea sediments, where the sedimentation rate was extremely low (Amari and Ozima 1985). Summary. ... He is produced by radioactive decay of U and Th. On the other hand, major part of 3 He is attributable to planetary (primordial) helium trapped deep in the Earth at the time of accretion.

The Ultraviolet Upturn in Elliptical Galaxies and ...

An extremely high abundance of helium (Y ~ ) allows for a working hypothesis, but its origin is unclear. Peng Nagai proposed that primordial helium sedimentation in dark halos over cosmic timescales may lead to extreme helium abundances in galaxy cluster centers.

SuperHeliumrich Populations and the Origin of Extreme ...

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The underlying stellar absorption contribution to the ...

The underlying stellar absorption contribution to the primordial helium abundance determination. ... The underlying stellar absorption contribution to the primordial helium abundance determination. Author. ... even Underlying stellar absorption contribution to primordial He determination 3 Flux + constant Wavelength Figure 2. SDSS ...

VOLUTIONARY STATUS AND I S C

the primordial helium contents (Y p ∼ ). On the basis of the welldefined stellar parameters of the ... ment of gravitational sedimentation of helium was not considered in their computations, so their estimation is too lower than the recent measurements of the primordial helium content (Y p …

Cosmological 'lost' lithium: Environmental solution ...

In the beginning there were four "fundamental" elements besides Hydrogen: Helium 3, Helium 4, Deuterium and Lithium7, four "light" isotopes produced by primordial nucleosynthesis (during the Big ...

Bio Dr. ERIC R SWITZER

The Sciences and Exploration Directorate is the largest Earth and space science research organization in the world. Its scientists advance understanding of the Earth and its lifesustaining environment, the Sun, the solar system, and the wider universe beyond. ... "Primordial helium recombination. II. Twophoton processes."

The UV Upturn in Elliptical galaxies and Environmental Effects

An extremely high abundance of helium (Y~) allows for a working hypothesis, but its origin is unclear. Peng Nagai (2009) proposed that primordial helium sedimentation in dark haloes over cosmic timescales may lead to extreme helium abundances in galaxy cluster centers.

Oxygen Wikipedia

Oxygen is the most abundant chemical element by mass in the Earth's biosphere, air, sea and land. Oxygen is the third most abundant chemical element in the universe, after hydrogen and helium. About % of the Sun's mass is oxygen.

Helium preenrichment in the starforming regions

In §2, 3 and 4 we study the diffusion of helium, respectively, in the DM dominated minihalos, in the MOND model and inside pressureconfined clouds. In §5 we consider the effect of turbulence on the helium abundance variation. In §6 we discuss the implications of our results. 2 GRAVITATIONAL SEDIMENTATION INSIDE DARK MATTER MINIHALOS

Helium Prospects Saskatchewan Publications Centre

HELIUM PROSPECTS IN SOUTHWEST SASKATCHEWAN ABSTRACT ... to one, helium is of primordial origin, ejected from the sun at the time of the Earth's formation. Another theory considers helium is ... which was originally prop:>sed by Rutherford and Soddy in 1903, is now well understood, and according to which the disinteg, ation of Uranium ...

Mechanisms controlling the distribution of helium and neon ...

Read "Mechanisms controlling the distribution of helium and neon in the Arctic seas: the case of the Knipovich Ridge, Earth and Planetary Science Letters" on DeepDyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips.

Publications | Weiss, Ray

THE 3He/4He ratio in deep Pacific water is 20–30% higher than in atmospheric helium because of injection of primordial helium from the mantle1,2. ... of particle dynamics relevant to modification of trace element composition of seawater due to particle transport and sedimentation flux. ... Recent Publications. Recent increases in the ...

A Comparison of the Interiors of Jupiter and Saturn CERN

A Comparison of the Interiors of Jupiter and Saturn Tristan Guillot Observatoire de la C^ote d’Azur ... It is however of primordial importance to derive ... The additional energy provided by helium sedimentation (or that of any other element) has been estimated by Hubbard et al. (1999). ...

Helium and Multiple Populations in the Massive Globular ...

Helium and Multiple Populations in the Massive Globular Cluster NGC6266 (M62) ... The red MS is consistent with a stellar population with primordial helium while the blue MS is highly heliumenhanced by∆Y=± Furthermore, the red MS exhibits an intrinsic ... like He sedimentation and the levitation of metals which alter the original ...

Spectroscopy of Horizontal Branch Stars in NGC 6752

elements heavier than helium) content is much in excess of ... investigation on primordial helium. The best candidates are, in principle. the unevolved main sequence stars, but. unfortu­ ... to rememberthat it is likely that sedimentation is already acting in the hot ...

chemical element | Definition, Origins, Distribution ...

Chemical element: Chemical element, any substance that cannot be decomposed into simpler substances by ordinary chemical processes. Elements are the fundamental materials of which all matter is composed. ... Recent determinations of the primordial helium abundance have converged on a value of 25 percent, ... Results of magmatism, sedimentation ...

HYDROGEN EOS AT MEGABAR PRESSURES AND THE SEARCH …

Saturn’s core via sedimentation is predicted. If helium is the separating component in Saturn, we predict that Saturn’s present atmospheric helium abundance should be reduced to Y = The depleted helium,amountingto7M E,wouldthenhavebeenaddedtoSaturn’score,increasing its primordial core mass of 16M E to a present core mass of 23M

arXiv:astroph/9912007v1 1 Dec 1999 CiteSeerX

sedimentation of helium nuclei toward cluster cores may at least partially account for the sharp peaks ... ter gas is entirely composed of hydrogen and helium with their primordial abundances, the value of µ will be higher at cluster center while asymptotically reaches at large

EFFECT OF HELIUM SEDIMENTATION ON XRAY …

primordial value, the analysis based on the assumption of the primordial abundance causes an underestimate of ρ gas by 5% and an overestimate of M tot by 12%. 3. HELIUM SEDIMENTATION IN XRAY CUSTERS Diffusion Equations Particle diffusion in clusters is characterized by the Burgers equations of a multicomponent fluid (Burgers 1969). Each

Helium preenrichment in the first stars CiteSeerX

In §2, 3 and 4 we study the diffusion of helium, respectively, in the DM dominated minihalos, in the MOND model and inside pressureconfined clouds. In §5 we consider the effect of turbulence on the helium abundance variation. In §6 we discuss the implications of our results. 2 GRAVITATIONAL SEDIMENTATION INSIDE DARK MATTER MINIHALOS

Terrigenous helium in deepsea sediments ScienceDirect

Terrigenous helium in deepsea sediments. ... for which the sedimentation rates are 1000–2000 cm · ka −1 ... Perhaps the most likely source of 3 He in crustal rocks is primordial mantle helium as postulated by Mamyrin and Tolstikhin (1984) and observed by Torgersen et al. (1995). If this were true, then the implication is that a ...