Hot oxygen escape from Mars: Simple scaling with solar EUV irradiance

Abstract We study wavefunctions of heavy scalars on de Sitter spacetime and their implications to dS/CFT correspondence. In contrast to light fields in the complementary series, heavy fields in the principal series oscillate outside the cosmological horizon. As a consequence, the quadratic term in the wavefunction does not follow a simple scaling and so it is hard to identify it with a conformal two-point function. In this paper, we demonstrate that it should be interpreted as a two-point function on a cyclic RG flow which is obtained by double-trace deformations of the dual CFT. This is analogous to the situation in nonrelativistic AdS/CFT with a bulk scalar whose mass squared is below the Breitenlohner-Freedman (BF) bound. We also provide a new dS/CFT dictionary relating de Sitter two-point functions and conformal two-point functions in the would-be dual CFT.

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Supermassive Black Hole feedback in early type galaxies

Proceedings of the International Astronomical Union ◽

10.1017/s1743921320004081 ◽

2020 ◽

Vol 15 (S359) ◽

pp. 119-125

Author(s):

W. Forman ◽

C. Jones ◽

A. Bogdan ◽

R. Kraft ◽

E. Churazov ◽

...

Keyword(s):

Dark Matter Halo ◽

Scaling Relations ◽

Radio Sources ◽

Early Type ◽

X Ray ◽

Galaxy Groups ◽

Sufficient Energy ◽

The Galaxy ◽

Simple Scaling ◽

Halo Masses

AbstractOptically luminous early type galaxies host X-ray luminous, hot atmospheres. These hot atmospheres, which we refer to as coronae, undergo the same cooling and feedback processes as are commonly found in their more massive cousins, the gas rich atmospheres of galaxy groups and galaxy clusters. In particular, the hot coronae around galaxies radiatively cool and show cavities in X-ray images that are filled with relativistic plasma originating from jets powered by supermassive black holes (SMBH) at the galaxy centers. We discuss the SMBH feedback using an X-ray survey of early type galaxies carried out using Chandra X-ray Observatory observations. Early type galaxies with coronae very commonly have weak X-ray active nuclei and have associated radio sources. Based on the enthalpy of observed cavities in the coronae, there is sufficient energy to “balance” the observed radiative cooling. There are a very few remarkable examples of optically faint galaxies that are 1) unusually X-ray luminous, 2) have large dark matter halo masses, and 3) have large SMBHs (e.g., NGC4342 and NGC4291). These properties suggest that, in some galaxies, star formation may have been truncated at early times, breaking the simple scaling relations.

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EXAFS Study of Co/Ag Multilayers

MRS Proceedings ◽

10.1557/proc-307-149 ◽

1993 ◽

Vol 307 ◽

Author(s):

C. L. Foiles ◽

R. Loloee ◽

T. I. Morrison

Keyword(s):

Magnetic Properties ◽

Significant Role ◽

Giant Magnetoresistance ◽

Structural Changes ◽

Multilayer System ◽

Basic Form ◽

Exafs Data ◽

Simple Scaling ◽

Exafs Study

ABSTRACTCo EXAFS data for these Co/Ag multilayers exhibit no changes in basic form and obey a simple scaling with Co thickness down to 6Å. Over this same thickness range the giant magnetoresistance and the manner in which magnetization approaches saturation change substantially. These results indicate that local structural changes do not play a significant role in altering the magnetic properties of this multilayer system.

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A simple scaling formula and monte carlo study of liquid semiconductor surfaces: application to CdxTe1−x

Scripta Metallurgica et Materialia ◽

10.1016/s0956-716x(99)80017-x ◽

1995 ◽

Vol 32 (1) ◽

pp. 87-92 ◽

Cited By ~ 4

Author(s):

Z.Q. Wang ◽

D. Stroud

Keyword(s):

Monte Carlo ◽

Monte Carlo Study ◽

Semiconductor Surfaces ◽

Liquid Semiconductor ◽

Simple Scaling

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Hierarchy and extremes in selections from pools of randomized proteins

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1517813113 ◽

2016 ◽

Vol 113 (13) ◽

pp. 3482-3487 ◽

Cited By ~ 18

Author(s):

Sébastien Boyer ◽

Dipanwita Biswas ◽

Ananda Kumar Soshee ◽

Natale Scaramozzino ◽

Clément Nizak ◽

...

Keyword(s):

High Throughput Sequencing ◽

Scaling Law ◽

Natural Populations ◽

Value Theory ◽

Darwinian Evolution ◽

Future Evolution ◽

Synthetic Protein ◽

Simple Scaling ◽

Protein Libraries

Variation and selection are the core principles of Darwinian evolution, but quantitatively relating the diversity of a population to its capacity to respond to selection is challenging. Here, we examine this problem at a molecular level in the context of populations of partially randomized proteins selected for binding to well-defined targets. We built several minimal protein libraries, screened them in vitro by phage display, and analyzed their response to selection by high-throughput sequencing. A statistical analysis of the results reveals two main findings. First, libraries with the same sequence diversity but built around different “frameworks” typically have vastly different responses; second, the distribution of responses of the best binders in a library follows a simple scaling law. We show how an elementary probabilistic model based on extreme value theory rationalizes the latter finding. Our results have implications for designing synthetic protein libraries, estimating the density of functional biomolecules in sequence space, characterizing diversity in natural populations, and experimentally investigating evolvability (i.e., the potential for future evolution).

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Influence of Blade Deterioration on Compressor and Turbine Performance

Volume 7: Education; Industrial and Cogeneration; Marine; Oil and Gas Applications ◽

10.1115/gt2008-50043 ◽

2008 ◽

Cited By ~ 2

Author(s):

M. Morini ◽

M. Pinelli ◽

P. R. Spina ◽

M. Venturini

Keyword(s):

Gas Turbine ◽

Mechanical Damage ◽

Turbine Stage ◽

Geometric Data ◽

Turbine Performance ◽

State Determination ◽

Performance Curves ◽

Common Causes ◽

Simple Scaling ◽

Main Effects

Gas turbine operating state determination consists of the assessment of the modification, due to deterioration and fault, of performance and geometric data characterizing machine components. One of the main effects of deterioration and fault is the modification of compressor and turbine performance maps. Since detailed information about actual modification of component maps is usually unavailable, many authors simulate the effects of deterioration and fault by a simple scaling of the map itself. In this paper, stage-by-stage models of the compressor and the turbine are used in order to assess the actual modification of compressor and turbine performance maps due to blade deterioration. The compressor is modeled by using generalized performance curves of each stage matched by means of a stage-stacking procedure. Each turbine stage is instead modeled as a couple of nozzles, a fixed one (stator) and a moving one (rotor). The results obtained by simulating some of the most common causes of blade deterioration (i.e., compressor fouling, compressor mechanical damage, turbine fouling and turbine erosion, occurring in one or more stages simultaneously) are reported in this paper. Moreover, compressor and turbine maps obtained through a stage-by-stage procedure are compared to the ones obtained by means of map scaling.

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Atmospheric loss from the dayside open polar region and its dependence on geomagnetic activity: implications for atmospheric escape on evolutionary timescales

Annales Geophysicae ◽

10.5194/angeo-35-721-2017 ◽

2017 ◽

Vol 35 (3) ◽

pp. 721-731 ◽

Cited By ~ 15

Author(s):

Rikard Slapak ◽

Audrey Schillings ◽

Hans Nilsson ◽

Masatoshi Yamauchi ◽

Lars-Göran Westerberg ◽

...

Keyword(s):

Geomagnetic Activity ◽

Polar Region ◽

Geomagnetic Storms ◽

Atmospheric Oxygen ◽

Atmospheric Escape ◽

Order Of Magnitude ◽

Ancient Times ◽

Oxygen Escape ◽

Atmospheric Loss ◽

Activity Condition

Abstract. We have investigated the total O+ escape rate from the dayside open polar region and its dependence on geomagnetic activity, specifically Kp. Two different escape routes of magnetospheric plasma into the solar wind, the plasma mantle, and the high-latitude dayside magnetosheath have been investigated separately. The flux of O+ in the plasma mantle is sufficiently fast to subsequently escape further down the magnetotail passing the neutral point, and it is nearly 3 times larger than that in the dayside magnetosheath. The contribution from the plasma mantle route is estimated as ∼ 3. 9 × 1024exp(0. 45 Kp) [s−1] with a 1 to 2 order of magnitude range for a given geomagnetic activity condition. The extrapolation of this result, including escape via the dayside magnetosheath, indicates an average O+ escape of 3 × 1026 s−1 for the most extreme geomagnetic storms. Assuming that the range is mainly caused by the solar EUV level, which was also larger in the past, the average O+ escape could have reached 1027–28 s−1 a few billion years ago. Integration over time suggests a total oxygen escape from ancient times until the present roughly equal to the atmospheric oxygen content today.

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