Predicting weak lensing statistics from halo mass reconstructions - General Abstract

2015 ◽  
Author(s):  
Spencer Everett
Keyword(s):  
Weak Lensing ◽  
General Abstract

General Abstract

2015 ◽  
Author(s):  
Christopher Pike
Keyword(s):  
General Abstract

Probing the electronic structure of buried interfaces - General Abstract

2015 ◽  
Author(s):  
Zachary Porter
Keyword(s):  
Electronic Structure ◽  
Buried Interfaces ◽  
General Abstract

scholarly journals Cosmological parameter biases from Doppler-shifted weak lensing in stage IV experiments

2021 ◽  
Vol 103 (12) ◽  
Author(s):  
Anurag C. Deshpande ◽  
Thomas D. Kitching
Keyword(s):  
Stage Iv ◽  
Cosmological Parameter ◽  
Weak Lensing

scholarly journals Cosmology with the cluster mass function: mass estimators and shape systematics in large weak lensing surveys

2009 ◽  
Vol 396 (1) ◽  
pp. 315-324 ◽  
Author(s):  
Virginia L. Corless ◽  
Lindsay J. King
Keyword(s):  
Mass Function ◽  
Weak Lensing ◽  
Cluster Mass

scholarly journals Quadratic estimators for CMB weak lensing

2021 ◽  
Vol 103 (8) ◽  
Author(s):  
Abhishek S. Maniyar ◽  
Yacine Ali-Haïmoud ◽  
Julien Carron ◽  
Antony Lewis ◽  
Mathew S. Madhavacheril
Keyword(s):  
Weak Lensing

scholarly journals Reconciling galaxy cluster shapes, measured by theorists versus observers

2020 ◽  
Vol 500 (2) ◽  
pp. 2627-2644
Author(s):  
David Harvey ◽  
Andrew Robertson ◽  
Sut-Ieng Tam ◽  
Mathilde Jauzac ◽  
Richard Massey ◽  
...  
Keyword(s):  
Hubble Space Telescope ◽  
Orientation Angle ◽  
Galaxy Cluster ◽  
Galactic Nuclei ◽  
Weak Lensing ◽  
Strongly Correlated ◽  
The Bahamas ◽  
Cluster Galaxy ◽  
Moments Of Inertia ◽  
X Ray

ABSTRACT If properly calibrated, the shapes of galaxy clusters can be used to investigate many physical processes: from feedback and quenching of star formation, to the nature of dark matter. Theorists frequently measure shapes using moments of inertia of simulated particles’. We instead create mock (optical, X-ray, strong-, and weak-lensing) observations of the 22 most massive ($\sim 10^{14.7}\, \mathrm{ M}_\odot$) relaxed clusters in the BAHAMAS simulations. We find that observable measures of shape are rounder. Even when moments of inertia are projected into 2D and evaluated at matched radius, they overestimate ellipticity by 56 per cent (compared to observable strong lensing) and 430 per cent (compared to observable weak lensing). Therefore, we propose matchable quantities and test them using observations of eight relaxed clusters from the Hubble Space Telescope (HST) and Chandra X-Ray Observatory. We also release our HST data reduction and lensing analysis software to the community. In real clusters, the ellipticity and orientation angle at all radii are strongly correlated. In simulated clusters, the ellipticity of inner (<rvir/20) regions becomes decoupled: for example, with greater misalignment of the central cluster galaxy. This may indicate overly efficient implementation of feedback from active galactic nuclei. Future exploitation of cluster shapes as a function of radii will require better understanding of core baryonic processes. Exploitation of shapes on any scale will require calibration on simulations extended all the way to mock observations.

OP75 Facts And Values In Health Technology Assessment: The Case Of Non-Invasive Prenatal Testing

2019 ◽  
Vol 35 (S1) ◽  
pp. 19-19
Author(s):  
Bart Bloemen ◽  
Maarten Jansen ◽  
Wouter Rijke ◽  
Wija Oortwijn ◽  
Gert Vanderwilt
Keyword(s):  
Health Technology Assessment ◽  
Technology Assessment ◽  
Prenatal Testing ◽  
Health Technology ◽  
Non Invasive ◽  
Relevant Evidence ◽  
Healthcare Technologies ◽  
General Abstract ◽  
Structured Questionnaire

IntroductionHealth Technology Assessment (HTA) is where facts and values meet: the evidence that is considered relevant to the assessment of a technology depends on the value framework used. In the context of the European project VALIDATE (Values in doing assessments of healthcare technologies), we assessed to what extent this interplay between facts and values is acknowledged in HTA reports on non-invasive prenatal testing (NIPT). Our aim is to gain a better understanding of this fact-value relationship, and to contribute to the development of capacity for ethical analyses in HTA.MethodsFive reviewers independently analyzed HTA reports on NIPT, obtained from the National Institute for Health Research (NIHR) HTA database, by answering a structured questionnaire on: (i) arguments, values, and conclusions; (ii) relations between values and collected evidence; (iii) operationalizations of the values involved. Ethical argumentation was analyzed using the method of specifying norms. This method holds that for general, abstract ethical principles to reach concrete cases, principles need to be specified in such a way as to achieve maximal coherence between different value commitments and practice. The results of the analysis were discussed in joint meetings to arrive at a consensus on interpretation.ResultsOur results show that the pivotal role of values in defining what counts as relevant evidence and why, is rarely acknowledged. The same holds for the importance of specifying values as a means to achieve greater coherence between the use of healthcare technologies and a range of values.ConclusionsThere is ample room for improvement in clarifying the role of values in HTA: they can serve to explain and justify what evidence is considered relevant to the assessment of a healthcare technology. Recognizing that abstract values need specification in order to reach concrete cases opens up new opportunities for exploring in what way values are affected by healthcare technologies.

scholarly journals Blending and obscuration in weak lensing magnification

2021 ◽  
Author(s):  
E Gaztanaga ◽  
S J Schmidt ◽  
M D Schneider ◽  
J A Tyson
Keyword(s):  
Systematic Errors ◽  
Weak Lensing ◽  
Wide Field ◽  
Photometric Redshifts ◽  
Field Surveys ◽  
Systematic Effects ◽  
The Impact ◽  
Close Pairs ◽  
Mass Profiles

Abstract We test the impact of some systematic errors in weak lensing magnification measurements with the COSMOS 30-band photo-z Survey flux limited to Iauto < 25.0 using correlations of both source galaxy counts and magnitudes. Systematic obscuration effects are measured by comparing counts and magnification correlations. We use the ACS-HST catalogs to identify potential blending objects (close pairs) and perform the magnification analyses with and without blended objects. We find that blending effects start to be important (∼ 0.04 mag obscuration) at angular scales smaller than 0.1 arcmin. Extinction and other systematic obscuration effects can be as large as 0.10 mag (U-band) but are typically smaller than 0.02 mag depending on the band. After applying these corrections, we measure a 3.9σ magnification signal that is consistent for both counts and magnitudes. The corresponding projected mass profiles of galaxies at redshift z ≃ 0.6 (MI ≃ −21) is Σ = 25 ± 6M⊙h3/pc2 at 0.1 Mpc/h, consistent with NFW type profile with M200 ≃ 2 × 1012M⊙h/pc2. Tangential shear and flux-size magnification over the same lenses show similar mass profiles. We conclude that magnification from counts and fluxes using photometric redshifts has the potential to provide complementary weak lensing information in future wide field surveys once we carefully take into account systematic effects, such as obscuration and blending.

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