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helium sedimentation primordial

[1107.0005] The UV Upturn in Elliptical galaxies and ...

Jun 30, 2011  An extremely high abundance of helium (Y~0.4) 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.

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Primordial Helium Abundance Test of Big Bang Cosmology ...

It is hard to exaggerate the theological significance of big bang cosmology. Until the twentieth century the Bible was the only “text” explicitly describing the fundamentals of big bang cosmology—a Causal Agent beyond space and time, a beginning of space and time, a beginning of matter and energy, continuous cosmic expansion, and constant laws of physics—as well as implying other ...

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(PDF) A measurement of the primordial helium abundance ...

However, a proper treatment of gravitational sedimentation of helium was not considered in their computations, so their estimation is too lower than the recent measurements of the primordial ...

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Helium-3 the Mantle: Primordial Signal or Cosmic Dust?

been2 x 10-15 cm3 cm-2year` over the past 40 million years [variation from 1 x 105to5 X 10-15cm3cm-2year-] (17). UsinganETflux of50Ggyear-1, basedon siderophiles (8) andanIDP3Heconcentra- tion of 4 x 10` cm3 g` (18), the total 3Hedelivered to the Earth is 2 x 106 cm3 year-1. Siderophiles, ofcourse, survive at- mospheric entry but some of the volatiles are lost by fragmentation andmelting dur-

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THE ULTRAVIOLET UPTURN IN ELLIPTICAL GALAXIES AND ...

stars in globular clusters have a common origin. An extremely high abundance of helium (Y ∼ 0.4) 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. In this scenario,

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Recombination Dynamics of Primordial Hydrogen and Helium ...

We calculated the ionization fraction for hydrogen and helium (He I) as a function of the redshift z by including the two-photon decays of high hydrogen and parahelium levels and the radiative transfer in the helium 23P1 ↔ 11 S 0 intercombination line. We show that this yields corrections of no more than a few percent to the ionization fraction for hydrogen and speeds up significantly the ...

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PROVEN AND HYPOTHETICAL HELIUM RESOURCES IN UTAH

Helium (He) is a colorless, odorless, chemically inert element of the noble gas family with two stable isotopes: the lighter, rarer primordial helium-3 (3He) and the heavier, more com-mon radiogenic helium-4 (4He) that has historically been a byproduct of natural gas production (figure 1) (Anderson, 1998; Gilfillan and others, 2008).

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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 helium-4 (4 He), along with small amounts of the hydrogen isotope deuterium (2 H or D ...

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Primordial helium abundance determination using sulphur as ...

ABSTRACT. The primordial helium abundance Y P is calculated using sulphur as metallicity tracer in the classical methodology (with Y P as an extrapolation of Y to zero metals). The calculated value, Y P, S = 0.244 ± 0.006, is in good agreement with the estimate from the Planck experiment, as well as, determinations in the literature using oxygen as the metallicity tracer.

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arXiv:astro-ph/9912007v2 30 Dec 1999

along with the helium nuclei. Here, we have not consid-ered the effects of magnetic fields and subcluster mergers, which may somewhat retard the sedimentation of helium nuclei (Rephaeli 1978; Gilfanov Sunyaev 1984). The sedimentation of helium nuclei in galaxy clusters will lead to a dramatic change of baryonic matter distri-bution.

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An MCMC determination of the primordial helium abundance ...

Nevertheless, accurate determination of the primordial helium abundance from observations of H II regions is constrained by both systematic and statistical uncertainties. In an attempt to better reduce the latter, and continue to better characterize the former, we apply MCMC methods to the large dataset recently compiled by Izotov, Thuan ...

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helium Definition, Properties, Uses, Facts Britannica

Helium, chemical element, inert gas of Group 18 (noble gases) of the periodic table. The second lightest element, helium is a colorless, odorless, and tasteless gas that becomes liquid at -268.9 degrees Celsius. The boiling and freezing points of helium are lower than those of any other known substance.

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THE HELIUM CONTENT OF GLOBULAR CLUSTERS: NGC 6121 (M4 ...

Mar 20, 2012  The U.S. Department of Energy's Office of Scientific and Technical Information

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The diffusion of helium through sedimentary rocks ...

Source of helium Two classes of helium can be envisaged: primordial helium, and radiogenic helium produced since the formation of the earth. In view of the wide cosmic abundance of helium it is clear that primordial helium did exist in the early stages of the earth's formation and a portion of this helium is still present. ... The sedimentation ...

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EFFECT OF HELIUM SEDIMENTATION ON X-RAY

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 X-RAY CUSTERS 3.1. Diffusion Equations Particle diffusion in clusters is characterized by the Burgers equations of a multicomponent fluid (Burgers 1969). Each

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A deep reservoir of primordial helium in the Earth

primordial helium are the deepest mantle and the core (image 1), its location remains unclear. This is one of the biggest mysteries in deep Earth science and still under intense debate.

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HELIUM SEDIMENTATION AND THE ULTRAVIOLET UPTURN

in Equation (2) further suppresses the sedimentation process. Substituting Equation (6) into Equation (1) and integrating over time, we obtain Y = Y 0e4Δt/3τ, where Y 0 is the primordial He mass fraction and τ 10Gyr(f gas/0.1)(T/10keV)−3/2(1+ 1.5dlnT/dlnr)−1 is the sedimentation timescale (Chuzhoy Loeb 2004). Note that the gas ...

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A deep reservoir of primordial helium in the Earth ...

May 06, 2021  A stable isotope of helium, 3He, was produced by the Big Bang and a remnant of the solar nebula. 3He is included in ocean island basalts, such as in Hawaiian volcanos, indicating it has been stored somewhere in the deep Earth and carried up to the surface in upwelling plumes. New computer simulations demonstrate that even in small amounts, helium can be dissolved in liquid iron

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On the abundance of primordial helium — [email protected]

We have used recent observations of helium-4, nitrogen, and oxygen from some four dozen, low-metallicity, extragalactic H II regions to define mean N vs. O, 4 He vs. N, and 4 He vs. O relations which are extrapolated to zero metallicity to determine the primordial 4 He mass fraction Y P.The data and various subsets of the data, selected on the basis of nitrogen and oxygen, are all consistent ...

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An MCMC determination of the primordial helium abundance ...

Apr 02, 2012  Nevertheless, accurate determination of the primordial helium abundance from observations of H II regions is constrained by both systematic and statistical uncertainties. In an attempt to better reduce the latter, and continue to better characterize the former, we apply MCMC methods to the large dataset recently compiled by Izotov, Thuan ...

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[PDF] Primordial helium entrained by the hottest mantle ...

Helium isotopes provide an important tool for tracing early-Earth, primordial reservoirs that have survived in the planet’s interior. Volcanic hotspot lavas, like those erupted at Hawaii and Iceland, can host rare, high 3He/4He isotopic ratios (up to 50 times the present atmospheric ratio, Ra) compared to the lower 3He/4He ratios identified in mid-ocean-ridge basalts that form by melting the ...

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THE ULTRAVIOLET UPTURN IN ELLIPTICAL GALAXIES AND ...

Aug 04, 2011  An extremely high abundance of helium (Y ~ 0.4) 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.

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(PDF) Primordial hydrogen-helium degassing, an overlooked ...

Degassing of primordial hydrogen and helium as the major energy source for internal terrestrial processes. By Alexander Vol and Arie Gilat. Hypothet-ical Physics and Chemistry of Volcanic Eruptions: The Doorway to Their Predic-tion. By Arie Gilat. Encyclopedia of Volcanoes.pdf.

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Primordial helium recombination. I. Feedback, line ...

Apr 15, 2008  OSTI.GOV Journal Article: Primordial helium recombination. I. Feedback, line transfer, and continuum opacity

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THE HELIUM CONTENT OF GLOBULAR CLUSTERS: NGC 6121 (M4 ...

Mar 20, 2012  This is a rare direct measurement of the (primordial) He abundance for stars belonging to the Na-rich/O-poor population of GC stars in a temperature regime where the He content is not altered by sedimentation or extreme mixing as suggested for the hottest, late helium flash HB stars.

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new determination of the primordial helium abundance using ...

ABSTRACT. The precision measurement of the primordial helium abundance Y p is a powerful probe of the early Universe. The most common way to determine Y p is the analyses of observations of metal-poor H ii regions found in blue compact dwarf galaxies. We present the spectroscopic sample of 100 H ii regions collected from the Sloan Digital Sky Survey. . The final analysed sample consists of our ...

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Helium-3 from the mantle: primordial signal or cosmic dust?

Helium-3 in hotspot magmas has been used as unambiguous evidence for the existence of a primordial, undegassed reservoir deep in the Earth's mantle. However, a large amount of helium-3 is delivered to the Earth's surface by interplanetary dust particles (IDPs). Recycling of deep-sea sediments contai

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Primordial helium entrained by the hottest mantle plumes

Helium isotopes provide an important tool for tracing early-Earth, primordial reservoirs that have survived in the planet's interior. Volcanic hotspot lavas, like those erupted at Hawaii and Iceland, can host rare, high 3 He/ 4 He isotopic ratios (up to 50 times the present atmospheric ratio, Ra) compared to the lower 3 He/ 4 He ratios identified in mid-ocean-ridge basalts that form by melting ...

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Helium-3 from the Mantle: Primordial Signal or Cosmic Dust?

of a primordial, undegassed reservoir deep in the Earth's mantle. However, a large amount of helium-3 is delivered to the Earth's surface by interplanetary dust particles (IDPs). Recycling of deep-sea sediments containing these particles to the mantle, and eventual incorporation in magma, can explain the high helium-3/helium-4 ratios of hotspot ...

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The primordial helium abundance - JSTOR

The primordial helium abundance Manuel Peimbert Instituto de Astronomi'a, Universidad Nacional Autonoma de Mexico, Mexico, 04510 DF, Mexico I present a brief review on the determination of the primordial helium abundance by unit mass, FP. I discuss the importance of the primordial helium abundance in: (a) cosmology, (b) testing the standard big ...

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Primordial neon, helium, and hydrogen in oceanic basalts ...

Aug 01, 1976  A primordial neon component in neon from Kilauea Volcano and deep-sea tholeiite glass has been identified by the presence of excess 20 Ne; relative to atmospheric neon the 20 Ne enrichments are 5.4% in Kilauea neon and about 2.5% in the basalts. The 20 Ne anomalies are associated with high 3 He/ 4 He ratios; the ratio in Kilauea helium is 15 times the atmospheric ratio, while mid-ocean ridge ...

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Rare Helium-Bearing Compound FeO2He Stabilized at

helium reservoir in deep Earth. DOI: 10.1103/PhysRevLett.121.255703. Helium is the second most abundant element in the Universe and its isotopes provide an important tool for tracing early-Earth, primordial compositions that have sur-vived in the planet’s interior [1–3]. It has been long hypothesized that deep mantle harbors domains containing

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The Hydrogen-to-Helium-4 Ratio in the Expanding Universe

P,He-4 = 50% is the primordial mass abundance of helium. On the assumption that the today abundances of helium-4 and hydrogen are respectively 24.5% and 75.5%, we obtain that the factor f is equal to f = 11.8. The era of quasars and big stars lasted about 10 Gyr i.e. ...

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What percentage of Helium-3 is primordial vs produced in stars

Mar 10, 2019  What percentage of Helium-3 is primordial vs produced in stars. Ask Question Asked 2 years, 4 months ago. Active 1 year, 10 months ago. Viewed 193 times 9 1 $\begingroup$ I tried to research but what I found is pretty limited. A very tiny but non zero percentage of primordial matter was Helium-3 or 3He. ...

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Helium-3 anomalies and crust-mantle interaction in Italy ...

Dec 01, 1985  The distribution of primordial 3 He in the crust of Italy has been investigated through a survey of groundwaters, hot-springs, exploration and production geothermal wells. The mantle-derived component varies from 0% to > 60% and reaches a maximum at Vulcano in the Eolian Islands. 3 He anomalies occur where the conductive heat flow is relatively high, but the relationships between heat

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Primordial Stellar Populations - CORE

Helium is mostly once ionized but, as long as the e ective temperature of the ionizing stars is above 90,000 K, emission lines of HeII can also be detected. In particular, for Teff =100,000 K, the fraction of twice ionized He is 29% for a model atmosphere SED and 10% for a black body SED.

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THE HELIUM CONTENT OF GLOBULAR CLUSTERS: NGC 6121

studies available in the literature. This is a rare direct measurement of the (primordial) He abundance for stars belonging to the Na-rich/O-poor population of GC stars in a temperature regime where the He content is not altered by sedimentation or extreme mixing as suggested for the hottest, late helium flash HB stars. Our results support

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'Space Force': the truth behind the helium-3 plot twist

Jun 03, 2020  Helium-3 is primordial, dating back to a planetary body’s earliest days. On Earth, it formed in the mantle of the planet, above the core and below the crust.

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(PDF) 19. HELIUM AND SULFUR ISOTOPES OF SULFIDE MINERALS ...

Helium and carbon geochemistry of hydrothermal fluids from the Mid-Okinawa Trough Back Arc Basin, southwest of Japan. By Jean-marie Auzende and Tetsuro Urabe. Helium and methane measurements in hydrothermal fluids from the mid-Atlantic ridge: The Snake Pit site at 23°N.

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