X‐Ray Total Mass Estimate for the Nearby Relaxed Cluster A3571

AbstractWe have analyzed Chandra/High Energy Transmission Grating spectra of the X-ray emission line gas in the Seyfert galaxy NGC 4151. The zeroth-order spectral images show extended H- and He-like O and Ne, up to a distance r ˜ 200 pc from the nucleus. Using the 1st-order spectra, we measure an average line velocity ˜230 km s–1, suggesting significant outflow of X-ray gas. We generated Cloudy photoionization models to fit the 1st-order spectra; the fit required three distinct emission-line components. To estimate the total mass of ionized gas (M) and the mass outflow rates, we applied the model parameters to fit the zeroth-order emission-line profiles of Ne IX and Ne X. We determined an M ≍ 5.4 × 105Mʘ. Assuming the same kinematic profile as that for the [O III] gas, derived from our analysis of Hubble Space Telescope/Space Telescope Imaging Spectrograph spectra, the peak X-ray mass outflow rate is approximately 1.8 Mʘ yr–1, at r ˜ 150 pc. The total mass and mass outflow rates are similar to those determined using [O III], implying that the X-ray gas is a major outflow component. However, unlike the optical outflows, the X-ray emitting mass outflow rate does not drop off at r > 100pc, which suggests that it may have a greater impact on the host galaxy.

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Evaluation of the Addition of α-Al2O3 on the Mechanical and Thermal Properties in Binding Geopolymer

Materials Science Forum ◽

10.4028/www.scientific.net/msf.820.497 ◽

2015 ◽

Vol 820 ◽

pp. 497-502 ◽

Cited By ~ 1

Author(s):

Danubia Lisbôa da Costa ◽

Rosiane Maria da Costa Farias ◽

Aluska Nascimento Simões Braga ◽

Romualdo Rodrigues Menezes ◽

Gelmires de Araujo Neves

Keyword(s):

Thermal Analysis ◽

Thermal Properties ◽

Construction Industry ◽

Total Mass ◽

Mechanical And Thermal Properties ◽

X Ray ◽

Total Mass Loss ◽

Alumina Addition ◽

Enhanced Properties ◽

Geopolymer Binder

Several years ago the study on modification of existing materials that have enhanced properties has gained prominence. In this scenario, the geopolymeric binders, currently widely used in the construction industry have emerged. Thus, this study aimed to evaluate the influence of alumina addition on the mechanical and thermal properties of metakaolin in geopolymer binder. The geopolymers were synthesized from mixtures of metakaolin/alumina and sodium hydroxide, pressed and characterized by diffraction of X-ray and differential thermal analysis and thermogravimetric. Two types of alumina were used in different amounts (14% and 7%) in order to evaluate the effect of the load binder obtained. It can be seen that the incorporation of alumina into the system caused an increase in strength of products obtained as well as a reduction in total mass loss of the sample , especially when the use of fine alumina.

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The low-mass pre-main sequence population of Scorpius OB1

Astronomy and Astrophysics ◽

10.1051/0004-6361/201730960 ◽

2018 ◽

Vol 615 ◽

pp. A148 ◽

Cited By ~ 10

Author(s):

Francesco Damiani

Keyword(s):

Total Mass ◽

Main Sequence ◽

Near Infrared ◽

Large Population ◽

X Ray ◽

Uv Excess ◽

Low Mass ◽

Ob Associations ◽

The Rich ◽

A New Technique

Context. The low-mass members of OB associations, expected to be a major component of their total population, are in most cases poorly studied because of the difficulty of selecting these faint stars in crowded sky regions. Our knowledge of many OB associations relies on only a relatively small number of massive members. Aims. We study here the Sco OB1 association, with the aim of a better characterization of its properties, such as global size and shape, member clusters and their morphology, age and formation history, and total mass. Methods. We use deep optical and near-infrared (NIR) photometry from the VPHAS+ and VVV surveys, over a wide area (2.6° × 2.6°), complemented by Spitzer infrared (IR) data, and Chandra and XMM-Newton X-ray data. A new technique is developed to find clusters of pre-main sequence M-type stars using suitable color-color diagrams, complementing existing selection techniques using narrow-band Hα photometry or NIR and ultraviolet (UV) excesses, and X-ray data. Results. We find a large population of approximately 4000 candidate low-mass Sco OB1 members whose spatial properties correlate well with those of Hα-emission, NIR-excess, UV-excess, and X-ray detected members, and unresolved X-ray emission. The low-mass population is spread among several interconnected subgroups: they coincide with the HII regions G345.45+1.50 and IC4628, and the rich clusters NGC 6231 and Trumpler 24, with an additional subcluster intermediate between these two. The total mass of Sco OB1 is estimated to be ~ 8500 M⊙. Indication of a sequence of star-formation events is found, from South (NGC 6231) to North (G345.45+1.50). We suggest that the diluted appearance of Trumpler 24 indicates that the cluster is now dissolving into the field, and that tidal stripping by NGC 6231 nearby contributes to the process.

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Microstructure, Mass and Chemical Analysis with 8 to 44 Angstrom X-Radiation

Advances in X-ray Analysis ◽

10.1154/s0376030800000471 ◽

1958 ◽

Vol 2 ◽

pp. 117-155 ◽

Cited By ~ 1

Author(s):

Burton L. Henke

Keyword(s):

High Resolution ◽

Chemical Analysis ◽

Mass Distribution ◽

Total Mass ◽

Biological Research ◽

Chemical Information ◽

Analysis Method ◽

X Ray

AbstractThe requirement of ultrasoft x-radiation (10 to 100A) for high resolution microradiographic analysis is established. Optimum methods are described for obtaining structure, mass distribution and mass-chemical information for microscopic sample regions as small as a few square microns and for total mass as small as a few micro-micrograms. The details of the techniques and of the instrumentation which are used in high resolution microradiographic analysis are presented.There has been a considerable amount of work reported on low magnification microradiography (up to 100 diameters) using conventional x-ray wavelengths.Relatively little work has been done in high resolution microradiography and with ultra soft x-radiation. Nearly all which has been reported has been in application to biological research where the need for such an analysis method seems to be greatest at this time. Outstanding among this work has been that of Engstrom and his co-workers.Much of the material which is presented in the present paper is intended as a supplement to that presented in the works of Engstrom and Lindstrom and with an emphasis upon the quantitative aspects of microradiographic analysis, using ultrasoft x-radiation.

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The Mass and Structure of the Remnant of Tycho's Supernova

Symposium - International Astronomical Union ◽

10.1017/s0074180900033611 ◽

1983 ◽

Vol 101 ◽

pp. 1-15 ◽

Cited By ~ 1

Author(s):

Paul Gorenstein ◽

Frederick Seward ◽

Wallace Tucker

Keyword(s):

Total Mass ◽

Column Density ◽

Supernova Remnant ◽

Average Density ◽

Equilibrium Calculation ◽

Free Expansion ◽

X Ray ◽

Upper Limit ◽

Interstellar Material ◽

Einstein Observatory

A high resolution X-ray image of Tycho's supernova remnant obtained from the Einstein Observatory reveals three components of X-ray emission that we identify with shocked interstellar material, diffuse ejecta, and clumpy ejecta. This picture is applied to derive the mass of X-ray emitting material. Assuming a distance of 3 kpc, an absorbing column density of 3 × 1021 atoms/cm2, and using an ion-electron non-equilibrium calculation for the emissivity, we find the average density of the ISM is 0.4 atoms/cm3, and the energy contained in the remnant is 1.4 × 1051 ergs. The total mass of X-ray emitting material in the remnant is ≈4 M⊙, ≈2 M⊙ ejecta and ≈2 M⊙ swept up, putting the remnant at an intermediate state between a free expansion and the Sedov phase. There is no evidence for neutron star. The upper limit on the surface temperature is in the range 1.1 to 1.8 × 106K.

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Measures of Galactic and Intergalactic Mass in Clusters

Symposium - International Astronomical Union ◽

10.1017/s0074180900128724 ◽

1998 ◽

Vol 179 ◽

pp. 266-267

Author(s):

D. Windridge ◽

S. Phillipps ◽

M. Birkinshaw

Keyword(s):

Spectral Emissivity ◽

Brightness Distribution ◽

Gas Temperature ◽

Total Electron ◽

X Ray ◽

A Value ◽

Sunyaev Zel'dovich Effect ◽

Radial Density Distribution ◽

Mass Estimate ◽

Simple Ratio

If a galaxy cluster's X-ray gas distribution follows an isothermal polytropic β model, we may write the electron radial density distribution as; ne = ne0(1 + r2/rc2)–3/2β, rc being the core radius and ne0 the central electron density. This may be related to both an X-ray surface brightness distribution and a Sunyaev-Zel'dovich effect distribution (Sarazin 1986). Fitting to observational data then enables us to constrain the value of β. The normalisation value, ne0, to obtain a total mass estimate is calculated via the relationship between the X-ray and S-Z distribution normalisation constants, and the gas temperature and spectral emissivity parameters from fits to the X-ray spectrum. We are then in a position to evaluate ne(r) and its integral; the total electron gas mass. If we can further assume that there exists a simple ratio between the electron and proton number densities within the gas, we may straightforwardly posit a value for the total gas mass. An additional method of determining the polytropic gas index exists, with optical constraints on the galactic velocity dispersion, through the relation; β = μmHσz2/kBTe. Studies at optical, as well as X-ray and radio wavelengths are thus useful as a corroborative measure in determining the total gas mass.

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Gender dimorphism in body composition abnormalities in acromegaly: males are more affected than females

Acta Endocrinologica ◽

10.1530/eje-08-0449 ◽

2008 ◽

Vol 159 (6) ◽

pp. 773-779 ◽

Cited By ~ 13

Author(s):

N Sucunza ◽

M J Barahona ◽

E Resmini ◽

J M Fernández-Real ◽

J Farrerons ◽

...

Keyword(s):

Body Composition ◽

Total Mass ◽

Mineral Content ◽

Gender Dimorphism ◽

Age And Gender ◽

X Ray ◽

Male Patients ◽

And Gender ◽

Design And Methods

BackgroundAcromegaly changes body composition (BC), but long-term gender differences have not been reported.ObjectiveTo evaluate BC in active and controlled acromegalic patients.Design and methodsClinical and biochemical variables and BC (by dual-energy X-ray absorptiometry) were evaluated in 60 acromegalic patients (19 active, 41 controlled) and 105 controls, matched for age and gender.ResultsAcromegalic males (n=24) had more total mass (89±13 vs 76.5±15.3 kg, P<0.001), lean body mass (LBM; 64.6±8.7 vs 56.4±5.8 kg, P<0.001), and bone mineral content (BMC; 2.9±0.5 vs 2.6±0.3 kg, P<0.05) than controls (n=33). Controlled male patients (n=14) had more total mass (89±14.7 vs 76.5±15.3 kg, P<0.05) and a trend to have more LBM (61.8±9.4 vs 56.4±5.8 kg, P=0.065) than controls. Only in active disease was a decrease in fat mass (FM) observed, compared with controlled patients and controls (males: 19.5±5.3 vs 27±6.2 and 25.9±4%, P<0.001; females: 30.3±6.7 vs 37.1±5.8 and 36.5±6.6%, P<0.01). In females, no further differences were observed. No differences in BMC were found between eugonadal and hypogonadal acromegalic patients, but in hypogonadal females, acromegaly appeared to prevent the BMC loss seen in hypogonadal postmenopausal controls. GH and IGF1 levels were negatively correlated with FM (males, P<0.05; females, P<0.001), but in the regression analysis GH was a predictor of FM only in women.ConclusionsControl of acromegaly reverts decreased FM in both genders; only in males more total mass and a trend for more LBM persist. The anabolic effect of GH on bone reverted in cured males, but persisted in females and appeared to override the bone loss of menopause.

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10.7. Absorption columns with bright X-ray sources near the galactic center: — mass estimation in the Galactic center region

Symposium - International Astronomical Union ◽

10.1017/s0074180900085521 ◽

1998 ◽

Vol 184 ◽

pp. 443-444 ◽

Cited By ~ 2

Author(s):

Masaaki Sakano ◽

Mamiko Nishiuchi ◽

Yoshitomo Maeda ◽

Katsuji Koyama ◽

Jun Yokogawa

Keyword(s):

Simple Form ◽

Total Mass ◽

Column Density ◽

Galactic Center ◽

Galactic Plane ◽

Angular Distance ◽

Mass Determination ◽

Mass Estimation ◽

X Ray ◽

Center Region

We report the column density distribution to the Galactic Center region using the X-ray binary observations with the X-ray satellite ASCA, and demonstrate a new method of the total mass determination near the Galactic Center. The column densities are given by a simple form as a function of the angular distance from the Galactic Plane. Assuming a disklike mass distribution of 500 pc radius, we estimate the total mass to be ~ 6 × 107M⊙.

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Dwarfs in the entourage of the Local Volume groups: flow tracers and cosmological probes

Proceedings of the International Astronomical Union ◽

10.1017/s1743921318005586 ◽

2018 ◽

Vol 14 (S344) ◽

pp. 488-490

Author(s):

Olga Kashibadze ◽

Igor Karachentsev ◽

Valentina Karachentseva

Keyword(s):

Total Mass ◽

Dwarf Galaxies ◽

Model Parameters ◽

Cosmic Expansion ◽

Local Volume ◽

Velocity Surface ◽

Optimal Value ◽

Virial Mass ◽

Mass Estimate ◽

Zero Velocity Surface

AbstractWe consider a sample of dwarf galaxies with accurate distances and velocities around 14 massive groups in the Local Volume. We combine all the data into a single synthetic group, and then determine its radius of the zero-velocity surface, separating it against the global cosmic expansion. Our estimation is derived from fitting the the spherical infall model (including effects of the cosmological constant) to the observational data.We found the optimal value of the radius to be 0.93 ± 0.02 Mpc. Assuming the Planck model parameters, it corresponds to the total mass of the synthetic group (1.6 ± 0.2) × 1012M⊙. Thus, we obtain the paradoxical result that the total mass of the synthetic group estimated on the scale of 3–4 its virial radius is only 60% of the virial mass estimate. Anyway, we conclude that wide outskirts of the nearby groups do not contain a large amount of hidden mass outside their virial radii.

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X-Ray and Gamma-Ray Signatures of Wolf-Rayet Supernova Explosions

Symposium - International Astronomical Union ◽

10.1017/s007418090004571x ◽

1991 ◽

Vol 143 ◽

pp. 537-546

Author(s):

Lih-Sin The ◽

Donald D. Clayton ◽

Adam Burrows

Keyword(s):

Total Mass ◽

Gamma Ray ◽

Expansion Velocity ◽

X Ray ◽

Line Shapes ◽

Transport Code ◽

Hard Radiation ◽

Supernova Explosions ◽

Monte Carlo Transport ◽

Rayet Star

It is widely speculated that a Type Ib supernova is the explosion of a Wolf-Rayet star. We calculate the X-ray and gamma-ray signatures of models of that type, assuming all hard photons to have originated with Ni decay chains, in hopes of providing diagnostics of the exposed-core models of massive stars, which constitute one model of the Wolf-Rayet stars, calculated by Ensman and Woosley (1988). These provide the characteristic luminosity peak and light curve of Type Ib supernovae for helium-core masses between 4 and 6 M⊙. We compute gamma-ray line shapes and fluxes and the Comptonized X-ray continuum resulting from the decay of the radioactive 56Co and 57Co isotopes that are synthesized by the explosion of the presupernova star (the suggested Wolf-Rayet or post-Wolf-Rayet star) with a Monte Carlo transport code. The expansion velocity, the total mass of the ejecta, the radial mixing of radioactivity in that ejecta, and the 56Ni yield effect both the strength and the evolution of the hard radiation. With the anticipated launch of Gamma Ray Observatory, we can hope to detect Type Ib supernovae to distances of 3 Mpc and utilize the characteristics of the gamma lines and X-ray spectrum to distinguish between differing Type Ib supernova models and to address their suggested relationship to Wolf-Rayet stars.

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