A5037699975- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- Cosmology and Gravitation Theories
- Scientific Research and Discoveries
- Astrophysics and Star Formation Studies
- Astrophysics and Cosmic Phenomena
- Astronomical Observations and Instrumentation
- Impact of Light on Environment and Health
- Gamma-ray bursts and supernovae
- Computational Physics and Python Applications
- Astrophysical Phenomena and Observations
- Plant Water Relations and Carbon Dynamics
- Solar and Space Plasma Dynamics
- Dark Matter and Cosmic Phenomena
- Geophysics and Gravity Measurements
- Advanced Measurement and Metrology Techniques
- Superconducting and THz Device Technology
- CCD and CMOS Imaging Sensors
- Adaptive optics and wavefront sensing
- Spectroscopy and Laser Applications
- History and Developments in Astronomy
- Black Holes and Theoretical Physics
- Open Source Software Innovations
University of Cambridge
2024-2025
University of British Columbia
2020-2023
Canadian Institute for Theoretical Astrophysics
2022-2023
University of Toronto
2022-2023
University of Massachusetts Amherst
2014-2021
Seoul National University
2013
We apply a halo-based group finder to four large redshift surveys, the 2MRS, 6dFGS, SDSS and 2dFGRS, construct catalogs in low-redshift Universe. The is based on that of Yang et al. but with an improved halo mass assignment so it can be applied uniformly various surveys galaxies. Halo masses are assigned groups according proxies stellar mass/luminosity member performances grouping galaxies common halos assignments tested using realistic mock samples constructed from hydrodynamical...
Context. The SPT0311–58 system resides in a massive dark-matter halo at z ∼ 6.9. It hosts two dusty galaxies (E and W) with combined star formation rate (SFR) of ∼3500 M ⊙ yr −1 , mostly obscured identified by the rest-frame IR emission. surrounding field exhibits an overdensity submillimetre sources, making it candidate protocluster. Aims. Our main goal is to characterise environment properties interstellar medium (ISM) within this unique system. Methods. We used spatially resolved...
Abstract We present a detailed analysis of JWST/NIRSpec and NIRCam observations ZF-UDS-7329, massive, quiescent galaxy at redshift z = 3.2, which has been put forward to challenge cosmology formation physics. study on the impact different star history (SFH) priors, stellar libraries, metallicity, initial mass function assumptions. Our results show that with formed M⋆ ≈ 1011.4 M⊙ (surviving M⋆, surv 1011.2 M⊙) specific star-formation rate sSFR 0.03 Gyr−1, efficiently in first billion years...
ABSTRACT Motivated by the recent JWST discovery of galaxy overdensities during Epoch Reionzation, we examine physical properties high-z protoclusters and their evolution using Full-hydro Large-scale structure simulations with All-sky Mapping for Interpretation Next Generation Observations (FLAMINGO) simulation suite. We investigate impact apertures used to define protoclusters, because heterogeneous in literature have limited our understanding population. Our results are insensitive...
Abstract We study the dependence of galaxy clustering on H i mass using ∼16,000 galaxies with redshift in range <?CDATA $0.0025\lt z\lt 0.05$?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mn>0.0025</mml:mn> <mml:mo><</mml:mo> <mml:mi>z</mml:mi> <mml:mn>0.05</mml:mn> </mml:math> and ${M}_{{\rm{H}}{\rm{I}}}\gt {10}^{8}\,{M}_{\odot }$?> <mml:msub> <mml:mrow> <mml:mi>M</mml:mi> </mml:mrow> <mml:mi mathvariant="normal">H</mml:mi> <mml:mspace width="0.25em"...
Abstract We use NIRSpec/MSA spectroscopy and NIRCam imaging to study a sample of 18 massive (log M⋆/M⊙ &gt; 10 dex), central quiescent galaxies at 2 ≤ z 5 in the GOODS fields, investigate their number density, star-formation histories, quenching timescales, incidence AGN. The data depth reaches log ≈ 9 dex, yet least-massive galaxy found has suggesting that is regulated by physical quantity scales with M⋆. With spectroscopy, we assess completeness purity photometric samples, finding...
Abstract We present the detection of kinetic Sunyaev–Zel’dovich effect (kSZE) signals from groups galaxies as a function halo mass down to <?CDATA $\mathrm{log}({M}_{500}/{M}_{\odot })\sim 12.3$?> using Planck cosmic microwave background maps and stacking about 40,000 galaxy systems with known positions, masses, peculiar velocities. The different are constrained simultaneously take care projection effects nearby halos. total kSZE flux within halos estimated implies that gas fraction in is...
We present a comparison of the physical properties ionized gas in circumgalactic (CGM) and intergalactic (IGM) media at $z\sim0$ between observations four cosmological hydrodynamical simulations: Illustris, TNG300 IllustrisTNG project, EAGLE, one Magneticum simulations. For observational data, we use that are inferred from cross-correlating Sunyaev-Zel'dovich effect (SZE) {\it Planck} CMB maps with haloes large-scale structure reconstructed Sloan Digital Sky Survey data. Both simulation...
We examine the quenched fraction of central and satellite galaxies as a function galaxy stellar mass, halo matter density their large scale environment. Matter densities are inferred from our ELUCID simulation, constrained simulation local Universe sampled by SDSS, while masses central/satellite classification taken group catalog Yang et al. The for total population increases systematically with three quantities. find that `environmental quenching efficiency', which quantifies is independent...
A galaxy group catalog is constructed from the 2MASS Redshift Survey (2MRS) with use of a halo-based finder. The halo mass associated estimated using `GAP' method based on luminosity central and its gap other member galaxies. Tests mock samples shows that this reliable, particularly for poor systems containing only few members. On average 80% all groups have completeness >0.8, about 65% zero contamination. Halo masses are typical uncertainty $\sim 0.35\,{\rm dex}$. application finder to 2MRS...
Abstract The intrinsic alignment of galaxies is an important systematic effect in weak-lensing surveys, which can affect the derived cosmological parameters. One direct way to distinguish different models and quantify their effects on measurement produce mock surveys. In this work, we use full-sky ray-tracing technique images from ELUCID N -body simulation run with WMAP9 cosmology. our model, assume that shape central elliptical galaxy follows dark matter halo, spiral halo spin. Using...
ABSTRACT As progenitors of the most massive objects, protoclusters are key to tracing evolution and star formation history Universe, responsible for ${\gtrsim }\, 20$ per cent cosmic at $z\, {\gt 2$. Using a combination state-of-the-art hydrodynamical simulations empirical models, we show that current galaxy models do not produce enough in match observations. We find rates (SFRs) predicted from an order magnitude lower than what is seen observations, despite relatively good agreement found...
In a recent study, using the distribution of galaxies in north galactic pole SDSS DR7 region enclosed 500$\mpch$ box, we carried out our ELUCID simulation (Wang et al. 2016, III). Here {\it light} dark matter halos and subhalos reconstructed with observations novel neighborhood} abundance matching method. Before make use thus established galaxy-subhalo connections to evaluate galaxy formation models, set explore reliability such link. For this purpose, focus on following few aspects...
We show that the ratio between stellar mass of central galaxy and its host halo, fc ≡ M*,c/Mh, can be used as an observable proxy halo assembly time, in groups with higher assembled their masses earlier. Using SDSS Yang et al., we study how correlates properties such colour, star formation rate, metallicity, bulge-to-disc ratio, size. Central galaxies a given > 0.02 tend to redder more quenched formation, smaller size, bulge dominated, increases. The trends colour appear reverse at < 0.02,...
A matched filter technique is applied to the Planck all-sky Compton y-parameter map measure thermal Sunyaev-Zel'dovich (tSZ) effect produced by galaxy groups of different halo masses selected from large redshift surveys in low-z Universe. Reliable mass estimates are available for all groups, which allows us bin similar investigate how tSZ depends on over a range. Filters simultaneously minimize projection effects. We find that integrated and hot gas content it implies consistent with...
Abstract As we demonstrated in Paper I, the quenched fractions of central and satellite galaxies as a function halo mass are extremely similar, long one controls for stellar mass. The same holds velocity dispersion, which is tightly correlated with black hole mass, both masses. Here use mock galaxy catalogs constructed from latest semi-analytic model, L-GALAXIES, state-of-the-art hydrodynamical simulation, EAGLE, to investigate whether these models can reproduce trends seen data. We also...
X-ray observations provide a potentially powerful tool to study starburst feedback. The analysis and interpretation of such remain challenging, however, due various complications, including the non-isothermality diffuse hot plasma inhomogeneity foreground absorption. We here illustrate complications way mitigate their effects by presenting an spectroscopy 30 Doradus nebula in Large Magellanic Clouds, based on 100 ks Suzaku observation. measure thermal chemical properties quantitatively...
Abstract We investigate the quenching properties of central and satellite galaxies, utilizing halo masses central–satellite identifications from Sloan Digital Sky Survey galaxy group catalog Yang et al. find that quenched fractions centrals satellites similar stellar have dependence on host mass. The similarity two populations is also found in terms specific star formation rate 4000 Å break. show dependencies bulge-to-total light ratio, velocity dispersion, halo-centric distance halos given...
We compare predictions of a number empirical models and numerical simulations galaxy formation to the conditional stellar mass functions (CSMF)of galaxies in groups different masses obtained recently by Lan et al. test how well accommodate data. The observational data clearly prefer model which star low-mass halos changes behavior at characteristic redshift $z_c\sim 2$. There is also tentative evidence that this depends on environment, becoming 4$ regions eventually evolve into rich clusters...
ABSTRACT The Planck list of high-redshift source candidates (the PHz catalogue) contains 2151 peaks in the cosmic infrared background, unresolved by Planck’s 5 arcmin beam. Follow-up spectroscopic observations have revealed that some these objects are $z\, {\approx }\, 2$ protoclusters and strong gravitational lenses but an unbiased survey has not yet been carried out. To this end, we used archival Herschel-SPIRE to study a uniformly selected sample 187 sources. In contrast with follow-up...
Motivated by the recent JWST discovery of galaxy overdensities during Epoch Reionzation, we examine physical properties high-$z$ protoclusters and their evolution using FLAMINGO simulation suite. We investigate impact apertures used to define protoclusters, because heterogeneous in literature have limited our understanding population. Our results are insensitive uncertainties subgrid models at a given resolution, whereas further investigation into dependence on numerical resolution is...
ABSTRACT Environmental effects on the formation and evolution of galaxies have been one leading questions in galaxy studies during past few decades. In this work, we investigate relationship between star activity their environmental matter density using cosmological hydrodynamic simulation Simba. The galactic indicators that explore include efficiency (SFE), specific rate (sSFR), molecular hydrogen mass fraction ($f^{*}_{\mathrm{H_2}}$), environment is considered as large-scale density,...
We examine the thermal energy contents of intergalactic medium (IGM) over three orders magnitude in both mass density and gas temperature using Sunyaev-Zel'dovich effect (tSZE). The analysis is based on {\it Planck} tSZE map cosmic field, reconstructed for SDSS DR7 volume sampled a grid cubic cells $(1h^{-1}{\rm Mpc})^3$, together with matched filter technique employed to maximize signal-to-noise. Our results show that pressure - relation IGM roughly power law given by an adiabatic equation...
A new way to construct a fitting formula for the halo mass function is presented. Our expressed as solution modified Jedamzik matrix equation that automatically satisfies normalization constraint. The characteristic parameters in terms of linear shear eigenvalues are empirically determined by analytic numerical results from high-resolution N-body simulation and found be independent scale, redshift background cosmology. with best-fit shown work excellently wide mass-range at various...