An Optimal Estimator of Intrinsic Alignments for Star-forming Galaxies in IllustrisTNG Simulation

Shi, Jingjing; Osato, Ken; Kurita, Toshiki; Takada, Masahiro

doi:10.48550/arxiv.2104.12329

Cited by 4 publications

(4 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the FQ pipeline, we require the background source redshift to be larger than 0.2 plus the foreground redshift. This ideally should take care of some of the systematics mentioned above as well as the impact of intrinsic alignment, one of the most important systematic effects for weak lensing (Hirata & Seljak 2004;Troxel & Ishak 2015;Yao et al 2017Yao et al , 2020Shi et al 2021). However, spectroscopic redshifts is ideal and can improve the precision of our weak lensing measurements.…”

Section: A Few Potential Systematicsmentioning

confidence: 99%

First measurement of the characteristic depletion radius of dark matter haloes from weak lensing

Fong,

Han,

Zhang

et al. 2022

Preprint

View full text Add to dashboard Cite

We use weak lensing observations to make the first measurement of the characteristic depletion radius, one of the three radii that characterize the region where matter is being depleted by growing haloes. The lenses are taken from the halo catalog produced by the extended halo-based group/cluster finder applied to DESI Legacy Imaging Surveys DR9, while the sources are extracted from the DECaLS DR8 imaging data with the F _Q pipeline. We study halo masses 12 < log(𝑀 grp [M /ℎ]) ≤ 15.3 within redshifts 0.2 ≤ 𝑧 ≤ 0.3. The virial and splashback radii are also measured and used to test the original findings on the depletion region. When binning haloes by mass, we find consistency between most of our measurements and predictions from the C G simulation, with exceptions to the lowest mass bins. The characteristic depletion radius is found to be roughly 2.5 times the virial radius and 1.7 − 3 times the splashback radius, in line with an approximately universal outer density profile, and the average enclosed density within the characteristic depletion radius is found to be roughly 29 times the mean matter density of the Universe in our sample. When binning haloes by both mass and a proxy for halo concentration, we do not detect a significant variation of the depletion radius with concentration, on which the simulation prediction is also sensitive to the choice of concentration proxy. We also confirm that the measured splashback radius varies with concentration differently from simulation predictions.

show abstract

Section: A Few Potential Systematicsmentioning

confidence: 99%

First measurement of the characteristic depletion radius of dark matter haloes from weak lensing

Fong,

Han,

Zhang

et al. 2022

Preprint

View full text Add to dashboard Cite

show abstract

“…Alternatively, the distribution of satellite galaxies also traces the halo mass distribution (e.g. Velliscig et al 2015;Ragone-Figueroa et al 2020;Gonzalez et al 2021;Shi et al 2021) and might be combined with the BCG shape for a better proxy of cluster orientation. We leave potential studies to future work.…”

Section: Discussionmentioning

confidence: 99%

Brightest cluster galaxies trace weak lensing mass bias and halo triaxiality in the three hundred project

Herbonnet

Crawford

Avestruz

et al. 2022

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

Galaxy clusters have a triaxial matter distribution. The weak-lensing signal, an important part in cosmological studies, measures the projected mass of all matter along the line-of-sight, and therefore changes with the orientation of the cluster. Studies suggest that the shape of the brightest cluster galaxy (BCG) in the centre of the cluster traces the underlying halo shape, enabling a method to account for projection effects. We use 324 simulated clusters at four redshifts between 0.1 and 0.6 from ‘The Three Hundred Project’ to quantify correlations between the orientation and shape of the BCG and the halo. We find that haloes and their embedded BCGs are aligned, with an average ∼20 degree angle between their major axes. The bias in weak lensing cluster mass estimates correlates with the orientation of both the halo and the BCG. Mimicking observations, we compute the projected shape of the BCG, as a measure of the BCG orientation, and find that it is most strongly correlated to the weak-lensing mass for relaxed clusters. We also test a 2-dimensional cluster relaxation proxy measured from BCG mass isocontours. The concentration of stellar mass in the projected BCG core compared to the total stellar mass provides an alternative proxy for the BCG orientation. We find that the concentration does not correlate to the weak-lensing mass bias, but does correlate with the true halo mass. These results indicate that the BCG shape and orientation for large samples of relaxed clusters can provide information to improve weak-lensing mass estimates.

show abstract

“…We did not find any signal of GI for blue galaxies, consistent with earlier studies (Mandelbaum et al 2011;Tonegawa et al 2018), while upcoming galaxy surveys such as the Subaru Prime Focus Spectrograph (Takada et al 2014) target blue galaxies at high redshifts. Recently, an interesting work of Shi et al (2021) presented a method to quantify IA of blue galaxies. Thus, not only red galaxies but blue galaxies can be good tracers of the tidal field.…”

Section: Discussionmentioning

confidence: 99%

First Evidence of Intrinsic Alignments of Red Galaxies at $z > 1$: Cross-correlation between CFHTLenS and FastSound Samples

Tonegawa,

Okumura

2021

Preprint

View full text Add to dashboard Cite

We report the first evidence of intrinsic alignment (IA) of red galaxies at z > 1. We measure the gravitational shear-intrinsic ellipticity (GI) cross-correlation function at z ∼ 1.3 using galaxy positions from the FastSound spectroscopic survey and galaxy shapes from Canada-Hawaii-France telescope lensing survey data. Adopting the non-linear alignment model, we obtain a 2.4σ level detection of the IA amplitude, A LA = 27.48 +11.53 −11.54 , larger than the value extrapolated from the constraints obtained at lower redshifts. Our measured IA is translated into a ∼ 20% contamination to the weak lensing power spectrum for the red galaxies. This marginal detection of IA for red galaxies at z > 1 motivates the continuing investigation of the nature of IA for weak lensing studies. Furthermore, our result provides the first step to utilize IA measurements in future high-z surveys as a cosmological probe, complementary to galaxy clustering and lensing.

show abstract

An Optimal Estimator of Intrinsic Alignments for Star-forming Galaxies in IllustrisTNG Simulation

Cited by 4 publications

References 30 publications

First measurement of the characteristic depletion radius of dark matter haloes from weak lensing

First measurement of the characteristic depletion radius of dark matter haloes from weak lensing

Brightest cluster galaxies trace weak lensing mass bias and halo triaxiality in the three hundred project

First Evidence of Intrinsic Alignments of Red Galaxies at $z > 1$: Cross-correlation between CFHTLenS and FastSound Samples

Contact Info

Product

Resources

About