scholarly journals Strong-lensing measurement of the total-mass-density profile out to three effective radii for z ∼ 0.5 early-type galaxies

2018 ◽  
Vol 480 (1) ◽  
pp. 431-438 ◽  
Author(s):  
Rui Li ◽  
Yiping Shu ◽  
Jiancheng Wang
Keyword(s):  
Total Mass ◽  
Mass Density ◽  
Three Dimensional ◽  
Stellar Dynamics ◽  
Average Density ◽  
Joint Analysis ◽  
Gravitational Lenses ◽  
Early Type ◽  
Three Samples ◽  
Strong Lensing

ABSTRACT We measure the total-mass-density profiles out to three effective radii for a sample of 63$z$ ∼ 0.5, massive early-type galaxies (ETGs) acting as strong gravitational lenses through a joint analysis of lensing and stellar dynamics. The compilation is selected from three galaxy-scale strong-lens samples, namely the Baryon Oscillation Spectroscopic Survey (BOSS) Emission-Line Lens Survey (BELLS), the BELLS for GALaxy-Lyα EmitteR sYstems Survey (BELLS GALLERY), and the Strong Lensing Legacy Survey (SL2S). Utilizing the wide source-redshift coverage (0.8–3.5) provided by these three samples, we build a statistically significant ensemble of massive ETGs for which robust mass measurements can be achieved within a broad range of Einstein radii up to three effective radii. Characterizing the three-dimensional total-mass-density distribution by a power-law profile as ρ ∝ r−γ, we find that the average logarithmic density slope for the entire sample is $\langle \gamma \rangle =2.000_{-0.032}^{+0.033}$ (68 per cent CL) with an intrinsic scatter of $\delta =0.180_{-0.028}^{+0.032}$. Further parametrizing 〈γ〉 as a function of redshift $z$ and the ratio of Einstein radius to effective radius Rein/Reff, we find that the average density distributions of these massive ETGs become steeper at later cosmic times and at larger radii, with magnitudes $\mathrm{d} \langle \gamma \rangle / \mathrm{d}z=-0.309_{-0.160}^{+0.166}$ and $\mathrm{d} \langle \gamma \rangle / \mathrm{d} \log _{10} ({R_{\rm ein}}/{R_{\rm eff}})=0.194_{-0.083}^{+0.092}$.

scholarly journals Density profile and line-of-sight mass contamination of SLACS gravitational lenses

2009 ◽  
Vol 5 (H15) ◽  
pp. 75-75
Author(s):  
C. C. Guimarães ◽  
Laerte Sodré
Keyword(s):  
Density Profile ◽  
Gravitational Lensing ◽  
Anisotropy Parameter ◽  
Stellar Dynamics ◽  
Joint Analysis ◽  
Gravitational Lenses ◽  
Confidence Levels ◽  
Effective Constant ◽  
Bayesian Evidence ◽  
The Galaxy

We use data from 58 strong lensing events surveyed by the Sloan Lens ACS Survey to estimate the projected galaxy mass inside their Einstein radii by two independent methods: stellar dynamics and strong gravitational lensing. We perform a joint analysis of both estimates examining the galaxy-lens density profile (that we approximate by a power law), the anisotropy of the velocity distribution (represented by an effective constant parameter), and a possible line-of-sigh (l.o.s.) mass contamination (which is suggested by various independent works in the literature). For each model, a likelihood analysis is performed to find the parameters that produce the best agreement between the dynamical and lensing masses, and the parameter confidence levels. The Bayesian evidence is calculated to allow a comparison among the models. We find a degeneracy among the slope of the density profile, the anisotropy parameter and the l.o.s. mass contamination. For a density profile close to isothermal, a l.o.s. mass contamination of the order of a few percent is possible, being less probable with larger anisotropy.

scholarly journals THE SL2S GALAXY-SCALE LENS SAMPLE. IV. THE DEPENDENCE OF THE TOTAL MASS DENSITY PROFILE OF EARLY-TYPE GALAXIES ON REDSHIFT, STELLAR MASS, AND SIZE

2013 ◽  
Vol 777 (2) ◽  
pp. 98 ◽  
Author(s):  
Alessandro Sonnenfeld ◽  
Tommaso Treu ◽  
Raphaël Gavazzi ◽  
Sherry H. Suyu ◽  
Philip J. Marshall ◽  
...  
Keyword(s):  
Density Profile ◽  
Total Mass ◽  
Mass Density ◽  
Stellar Mass ◽  
Early Type ◽  
Mass Density Profile

scholarly journals Dark-Matter in Galaxies from Gravitational Lensing and Stellar Dynamics Studies

2009 ◽  
Vol 5 (H15) ◽  
pp. 74-74
Author(s):  
L. V. E. Koopmans
Keyword(s):  
Dark Matter ◽  
Mass Distribution ◽  
Density Profile ◽  
Gravitational Lensing ◽  
Total Mass ◽  
Stellar Dynamics ◽  
Early Type ◽  
Complementary Methods ◽  
Strong Gravitational Lensing

AbstractStrong gravitational lensing and stellar dynamics provide two complementary methods in the study of the mass distribution of dark matter in galaxies out to redshift of unity. They are particularly powerful in the determination of the total mass and the density profile of mass early-type galaxies on kpc to tens of kpc scales, and also reveal the presence of mass-substructure on sub-kpc scale. I will shortly discuss these topics in this review.

scholarly journals The Central Dark Matter Fraction of Massive Early-Type Galaxies

2022 ◽  
Vol 8 ◽  
Author(s):  
C. Tortora ◽  
N. R. Napolitano
Keyword(s):  
Dark Matter ◽  
Total Mass ◽  
Mass Density ◽  
Mass Function ◽  
Initial Mass Function ◽  
Early Type ◽  
Galaxy Model ◽  
Stellar Initial Mass Function ◽  
Evolution With Time

Dark matter (DM) is predicted to be the dominant mass component in galaxies. In the central region of early-type galaxies it is expected to account for a large amount of the total mass, although the stellar mass should still represent the majority of the mass budget, depending on the stellar initial mass function (IMF). We discuss latest results on the DM fraction and mean DM density for local galaxies and explore their evolution with redshifts in the last 8 Gyr of the cosmic history. We compare these results with expectations from the ΛCDM model and discuss the role of the IMF and galaxy model through the central total mass density slope. We finally present future perspectives offered by next-generation instruments/surveys (Rubin/LSST, Euclid, CSST, WEAVE, 4MOST, and DESI), which will provide the unique chance to measure the DM evolution with time for an unprecedented number of galaxies and constrain their evolutionary scenario.

Electron microscopy of T4 DNA helix destabilizing protein (GP32*I) crystal

1983 ◽  
Vol 41 ◽  
pp. 728-729
Author(s):  
H.A. Cohen ◽  
W. Chiu ◽  
J. Hosoda
Keyword(s):  
Mass Density ◽  
Three Dimensional ◽  
Average Density ◽  
Dimensional Structure ◽  
Long Range Order ◽  
Alpha Helices ◽  
Negative Stain ◽  
T4 Phage ◽  
Density Map ◽  
Dna Helix

The DNA helix destabilizing protein of T4 phage, gp32, may be enzymatically cleaved to produce the major fragment gp32*I, which crystallizes as thin platelets suitable for electron diffraction and imaging. The low resolution three-dimensional structure of gp32*I was previously determined. That model, based on the exclusion of negative stain showed that the protein crystallizes as dimers about 90 Å high, with each monomer about 20 Å in diameter. Since negative stain limits possible resolution to about 15 Å, glucose embedding was used to maintain the long range order of the crystal. A projected mass density map was reconstructed to 7.6 Å which resolved five masses in each dimer. The map was difficult to interpret since the average density of the protein was only slightly less than that of the embedding media. As a consequence, regions of protein that are denser than average (e.g. alpha helices running perpendicular to the surface of the crystal) approach the mass density of the embedding glucose and thus are invisible.

scholarly journals Strong lensing models of eight CLASH clusters from extensive spectroscopy: Accurate total mass reconstructions in the cores

2019 ◽  
Vol 632 ◽  
pp. A36 ◽  
Author(s):  
G. B. Caminha ◽  
P. Rosati ◽  
C. Grillo ◽  
G. Rosani ◽  
K. I. Caputi ◽  
...  
Keyword(s):  
Total Mass ◽  
High Efficiency ◽  
Mass Density ◽  
Mean Value ◽  
Parametric Models ◽  
Large Field ◽  
Redshift Range ◽  
Multiple Images ◽  
Mass Distributions ◽  
Strong Lensing

We carried out a detailed strong lensing analysis of a sub-sample of eight galaxy clusters of the Cluster Lensing And Supernova survey with Hubble (CLASH) in the redshift range of zcluster = [0.23 − 0.59] using extensive spectroscopic information, primarily from the Multi Unit Spectroscopic Explorer (MUSE) archival data and complemented with CLASH-VLT redshift measurements. The observed positions of the multiple images of strongly lensed background sources were used to constrain parametric models describing the cluster total mass distributions. Different models were tested in each cluster depending on the complexity of its mass distribution and on the number of detected multiple images. Four clusters show more than five spectroscopically confirmed multiple image families. In this sample, we did not make use of families that are only photometrically identified in order to reduce model degeneracies between the values of the total mass of a cluster source redshifts, in addition to systematics due to the potential misidentifications of multiple images. For the remaining four clusters, we used additional families without any spectroscopic confirmation to increase the number of strong lensing constraints up to the number of free parameters in our parametric models. We present spectroscopic confirmation of 27 multiply lensed sources, with no previous spectroscopic measurements, spanning over the redshift range of zsrc = [0.7 − 6.1]. Moreover, we confirm an average of 48 galaxy members in the core of each cluster thanks to the high efficiency and large field of view of MUSE. We used this information to derive precise strong lensing models, projected total mass distributions, and magnification maps. We show that, despite having different properties (i.e. number of mass components, total mass, redshift, etc.), the projected total mass and mass density profiles of all clusters have very similar shapes when rescaled by independent measurements of M200c and R200c. Specifically, we measured the mean value of the projected total mass of our cluster sample within 10 (20)% of R200c to be 0.13 (0.32) of M200c, with a remarkably small scatter of 5 (6)%. Furthermore, the large number of high-z sources and the precise magnification maps derived in this work for four clusters add up to the sample of high-quality gravitational telescopes to be used to study the faint and distant Universe.

scholarly journals The progeny of a cosmic titan: a massive multi-component proto-supercluster in formation at z = 2.45 in VUDS

2018 ◽  
Vol 619 ◽  
pp. A49 ◽  
Author(s):  
O. Cucciati ◽  
B. C. Lemaux ◽  
G. Zamorani ◽  
O. Le Fèvre ◽  
L. A. M. Tasca ◽  
...  
Keyword(s):  
Total Mass ◽  
Voronoi Tessellation ◽  
Complex Structure ◽  
Statistical Treatment ◽  
Three Dimensional ◽  
Average Density ◽  
Photometric Redshifts ◽  
Density Peaks ◽  
Imaging And Spectroscopy ◽  
The Individual

We unveil the complex shape of a proto-supercluster at z ∼ 2.45 in the COSMOS field exploiting the synergy of both spectroscopic and photometric redshifts. Thanks to the spectroscopic redshifts of the VIMOS Ultra-Deep Survey (VUDS), complemented by the zCOSMOS-Deep spectroscopic sample and high-quality photometric redshifts, we compute the three-dimensional (3D) overdensity field in a volume of ∼100 × 100 × 250 comoving Mpc3 in the central region of the COSMOS field, centred at z ∼ 2.45 along the line of sight. The method relies on a two-dimensional (2D) Voronoi tessellation in overlapping redshift slices that is converted into a 3D density field, where the galaxy distribution in each slice is constructed using a statistical treatment of both spectroscopic and photometric redshifts. In this volume, we identify a proto-supercluster, dubbed “Hyperion” for its immense size and mass, which extends over a volume of ∼60 × 60 × 150 comoving Mpc3 and has an estimated total mass of ∼4.8 × 1015 M⊙. This immensely complex structure contains at least seven density peaks within 2.4 ≲ z ≲ 2.5 connected by filaments that exceed the average density of the volume. We estimate the total mass of the individual peaks, Mtot, based on their inferred average matter density, and find a range of masses from ∼0.1 × 1014 M⊙ to ∼2.7 × 1014 M⊙. By using spectroscopic members of each peak, we obtain the velocity dispersion of the galaxies in the peaks, and then their virial mass Mvir (under the strong assumption that they are virialised). The agreement between Mvir and Mtot is surprisingly good, at less than 1−2σ, considering that (almost all) the peaks are probably not yet virialised. According to the spherical collapse model, these peaks have already started or are about to start collapsing, and they are all predicted to be virialised by redshift z ∼ 0.8−1.6. We finally perform a careful comparison with the literature, given that smaller components of this proto-supercluster had previously been identified using either heterogeneous galaxy samples (Lyα emitters, sub-mm starbursting galaxies, CO emitting galaxies) or 3D Lyα forest tomography on a smaller area. With VUDS, we obtain, for the first time across the central ∼1 deg2 of the COSMOS field, a panoramic view of this large structure, that encompasses, connects, and considerably expands in a homogeneous way on all previous detections of the various sub-components. The characteristics of this exceptional proto-supercluster, its redshift, its richness over a large volume, the clear detection of its sub-components, together with the extensive multi-wavelength imaging and spectroscopy granted by the COSMOS field, provide us the unique possibility to study a rich supercluster in formation.

Image formation analysis of thick biological specimens using three-dimensional power-spectra of through focus series

1994 ◽  
Vol 52 ◽  
pp. 124-125
Author(s):  
Karen F. Han
Keyword(s):  
Inelastic Scattering ◽  
Imaging Techniques ◽  
Mass Density ◽  
Relative Proportion ◽  
Three Dimensional ◽  
Power Spectra ◽  
Image Formation ◽  
Energy Filtering ◽  
Ewald Sphere ◽  
Nonlinear Imaging

The primary focus in our laboratory is the study of higher order chromatin structure using three dimensional electron microscope tomography. Three dimensional tomography involves the deconstruction of an object by combining multiple projection views of the object at different tilt angles, image intensities are not always accurate representations of the projected object mass density, due to the effects of electron-specimen interactions and microscope lens aberrations. Therefore, an understanding of the mechanism of image formation is important for interpreting the images. The image formation for thick biological specimens has been analyzed by using both energy filtering and Ewald sphere constructions. Surprisingly, there is a significant amount of coherent transfer for our thick specimens. The relative amount of coherent transfer is correlated with the relative proportion of elastically scattered electrons using electron energy loss spectoscopy and imaging techniques.Electron-specimen interactions include single and multiple, elastic and inelastic scattering. Multiple and inelastic scattering events give rise to nonlinear imaging effects which complicates the interpretation of collected images.

scholarly journals Limited Sampling Strategy for Determination of Ibrutinib Plasma Exposure: Joint Analyses with Metabolite Data

2021 ◽  
Vol 14 (2) ◽  
pp. 162
Author(s):  
Félicien Le Louedec ◽  
Fanny Gallais ◽  
Fabienne Thomas ◽  
Mélanie White-Koning ◽  
Ben Allal ◽  
...  
Keyword(s):  
Area Under The Curve ◽  
Sampling Strategy ◽  
Predictive Performance ◽  
Pharmacokinetic Profile ◽  
Limited Sampling Strategy ◽  
Joint Analysis ◽  
Therapeutic Drug ◽  
Post Dose ◽  
Limited Sampling ◽  
Three Samples

Therapeutic drug monitoring of ibrutinib is based on the area under the curve of concentration vs. time (AUCIBRU) instead of trough concentration (Cmin,ss) because of a limited accumulation in plasma. Our objective was to identify a limited sampling strategy (LSS) to estimate AUCIBRU associated with Bayesian estimation. The actual AUCIBRU of 85 patients was determined by the Bayesian analysis of the full pharmacokinetic profile of ibrutinib concentrations (pre-dose T0 and 0.5, 1, 2, 4 and 6 h post-dose) and experimental AUCIBRU were derived considering combinations of one to four sampling times. The T0–1–2–4 design was the most accurate LSS (root-mean-square error RMSE = 11.0%), and three-point strategies removing the 1 h or 2 h points (RMSE = 22.7% and 14.5%, respectively) also showed good accuracy. The correlation between the actual AUCIBRU and Cmin,ss was poor (r2 = 0.25). The joint analysis of dihydrodiol-ibrutinib metabolite concentrations did not improve the predictive performance of AUCIBRU. These results were confirmed in a prospective validation cohort (n = 27 patients). At least three samples, within the pre-dose and 4 h post-dose period, are necessary to estimate ibrutinib exposure accurately.

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