Feven Markos Hunde, Oliver Newton, Wojciech A. Hellwing, Maciej Bilicki, Krishna Naidoo
Using the high-resolution Nbody{} cosmological simulation COLOR, we explore the cosmic web (CW) environmental effects on subhalo populations and their internal properties. We use cactus{}, a new implementation of the state-of-the-art segmentation method nexus{}, to delineate the simulation volume into nodes, filaments, walls, and voids. We group host halos by virial mass and segment each mass bin into consecutive CW elements. This reveals that subhalo populations in hosts within specific environments differ on average from the cosmic mean. The subhalo mass function is affected strongly, where hosts in filaments typically contain more subhalos (5 to 30%), while hosts in voids are subhalo-poor, with 50% fewer subhalos. We find that the abundance of the most massive subhalos, with reduced masses of $muequiv M_mathrm{sub}/M_{200}geq0.1$ is most sensitive to the CW environment. A corresponding picture emerges when looking at subhalo mass fractions, $f_mathrm{sub}$, where the filament hosts are significantly more `granular' (having higher $f_mathrm{sub}$) than the cosmic mean, while the void hosts have much smoother density distributions (with $f_mathrm{sub}$ lower by $10{-}40%$ than the mean). Finally, when we look at the subhalo internal kinematic vmax{}--rmax{} relations, we find that subhalos located in the void and wall hosts exhibit density profiles with lower concentrations than the mean, while the filament hosts demonstrate much more concentrated mass profiles. Across all our samples, the effect of the CW environment generally strengthens with decreasing host halo virial mass. Our results show that host location in the large-scale CW introduces significant systematic effects on internal subhalo properties and population statistics. Understanding and accounting for them is crucial for unbiased interpretation of observations related to small scales and satellite galaxies.
{"title":"Caught in the cosmic web: environmental effects on subhalo abundance and internal density profiles","authors":"Feven Markos Hunde, Oliver Newton, Wojciech A. Hellwing, Maciej Bilicki, Krishna Naidoo","doi":"arxiv-2409.09226","DOIUrl":"https://doi.org/arxiv-2409.09226","url":null,"abstract":"Using the high-resolution Nbody{} cosmological simulation COLOR, we explore\u0000the cosmic web (CW) environmental effects on subhalo populations and their\u0000internal properties. We use cactus{}, a new implementation of the\u0000state-of-the-art segmentation method nexus{}, to delineate the simulation\u0000volume into nodes, filaments, walls, and voids. We group host halos by virial\u0000mass and segment each mass bin into consecutive CW elements. This reveals that\u0000subhalo populations in hosts within specific environments differ on average\u0000from the cosmic mean. The subhalo mass function is affected strongly, where\u0000hosts in filaments typically contain more subhalos (5 to 30%), while hosts in\u0000voids are subhalo-poor, with 50% fewer subhalos. We find that the abundance of\u0000the most massive subhalos, with reduced masses of $muequiv\u0000M_mathrm{sub}/M_{200}geq0.1$ is most sensitive to the CW environment. A\u0000corresponding picture emerges when looking at subhalo mass fractions,\u0000$f_mathrm{sub}$, where the filament hosts are significantly more `granular'\u0000(having higher $f_mathrm{sub}$) than the cosmic mean, while the void hosts\u0000have much smoother density distributions (with $f_mathrm{sub}$ lower by\u0000$10{-}40%$ than the mean). Finally, when we look at the subhalo internal\u0000kinematic vmax{}--rmax{} relations, we find that subhalos located in the void\u0000and wall hosts exhibit density profiles with lower concentrations than the\u0000mean, while the filament hosts demonstrate much more concentrated mass\u0000profiles. Across all our samples, the effect of the CW environment generally\u0000strengthens with decreasing host halo virial mass. Our results show that host\u0000location in the large-scale CW introduces significant systematic effects on\u0000internal subhalo properties and population statistics. Understanding and\u0000accounting for them is crucial for unbiased interpretation of observations\u0000related to small scales and satellite galaxies.","PeriodicalId":501207,"journal":{"name":"arXiv - PHYS - Cosmology and Nongalactic Astrophysics","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257643","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We study the contribution of large scalar perturbations sourced by a sharp feature during cosmic inflation to the stochastic gravitational wave background (SGWB), extending our previous work to include the SGWB sourced during the inflationary era. We focus in particular on three-field inflation, since the third dynamical field is the first not privileged by the perturbations' equations of motion and allows a more direct generalization to $N$-field inflation. For the first time, we study the three-field isocurvature perturbations sourced during the feature and include the effects of isocurvature masses. In addition to a two-field limit, we find that the third field's dynamics during the feature can source large isocurvature transients which then later decay, leaving an inflationary-era-sourced SGWB as their only observable signature. We find that the inflationary-era signal shape near the peak is largely independent of the number of dynamical fields and has a greatly enhanced amplitude sourced by the large isocurvature transient, suppressing the radiation-era contribution and opening a new window of detectable parameter space with small adiabatic enhancement. The largest enhancements we study could easily violate backreaction constraints, but much of parameter space remains under perturbative control. These SGWBs could be visible in LISA and other gravitational wave experiments, leaving an almost universal signature of sharp features during multi-field inflation, even when the sourcing isocurvature decays to unobservability shortly afterwards.
{"title":"Primordial Stochastic Gravitational Wave Backgrounds from a Sharp Feature in Three-field Inflation II: The Inflationary Era","authors":"Vikas Aragam, Sonia Paban, Robert Rosati","doi":"arxiv-2409.09023","DOIUrl":"https://doi.org/arxiv-2409.09023","url":null,"abstract":"We study the contribution of large scalar perturbations sourced by a sharp\u0000feature during cosmic inflation to the stochastic gravitational wave background\u0000(SGWB), extending our previous work to include the SGWB sourced during the\u0000inflationary era. We focus in particular on three-field inflation, since the\u0000third dynamical field is the first not privileged by the perturbations'\u0000equations of motion and allows a more direct generalization to $N$-field\u0000inflation. For the first time, we study the three-field isocurvature\u0000perturbations sourced during the feature and include the effects of\u0000isocurvature masses. In addition to a two-field limit, we find that the third\u0000field's dynamics during the feature can source large isocurvature transients\u0000which then later decay, leaving an inflationary-era-sourced SGWB as their only\u0000observable signature. We find that the inflationary-era signal shape near the\u0000peak is largely independent of the number of dynamical fields and has a greatly\u0000enhanced amplitude sourced by the large isocurvature transient, suppressing the\u0000radiation-era contribution and opening a new window of detectable parameter\u0000space with small adiabatic enhancement. The largest enhancements we study could\u0000easily violate backreaction constraints, but much of parameter space remains\u0000under perturbative control. These SGWBs could be visible in LISA and other\u0000gravitational wave experiments, leaving an almost universal signature of sharp\u0000features during multi-field inflation, even when the sourcing isocurvature\u0000decays to unobservability shortly afterwards.","PeriodicalId":501207,"journal":{"name":"arXiv - PHYS - Cosmology and Nongalactic Astrophysics","volume":"13 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257675","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sultan Hassan, Eve C. Ostriker, Chang-Goo Kim, Greg L. Bryan, Jan D. Burger, Drummond B. Fielding, John C. Forbes, Shy Genel, Lars Hernquist, Sarah M. R. Jeffreson, Bhawna Motwani, Matthew C. Smith, Rachel S. Somerville, Ulrich P. Steinwandel, Romain Teyssier
Traditional star formation subgrid models implemented in cosmological galaxy formation simulations, such as that of Springel & Hernquist (2003, hereafter SH03), employ adjustable parameters to satisfy constraints measured in the local Universe. In recent years, however, theory and spatially-resolved simulations of the turbulent, multiphase, star-forming ISM have begun to produce new first-principles models, which when fully developed can replace traditional subgrid prescriptions. This approach has advantages of being physically motivated and predictive rather than empirically tuned, and allowing for varying environmental conditions rather than being tied to local Universe conditions. As a prototype of this new approach, by combining calibrations from the TIGRESS numerical framework with the Pressure-Regulated Feedback-Modulated (PRFM) theory, simple formulae can be obtained for both the gas depletion time and an effective equation of state. Considering galaxies in TNG50, we compare the "native" simulation outputs with post-processed predictions from PRFM. At TNG50 resolution, the total midplane pressure is nearly equal to the total ISM weight, indicating that galaxies in TNG50 are close to satisfying vertical equilibrium. The measured gas scale height is also close to theoretical equilibrium predictions. The slopes of the effective equations of states are similar, but with effective velocity dispersion normalization from SH03 slightly larger than that from current TIGRESS simulations. Because of this and the decrease in PRFM feedback yield at high pressure, the PRFM model predicts shorter gas depletion times than the SH03 model at high densities and redshift. Our results represent a first step towards implementing new, numerically calibrated subgrid algorithms in cosmological galaxy formation simulations.
{"title":"Towards Implementation of the Pressure-Regulated, Feedback-Modulated Model of Star Formation in Cosmological Simulations: Methods and Application to TNG","authors":"Sultan Hassan, Eve C. Ostriker, Chang-Goo Kim, Greg L. Bryan, Jan D. Burger, Drummond B. Fielding, John C. Forbes, Shy Genel, Lars Hernquist, Sarah M. R. Jeffreson, Bhawna Motwani, Matthew C. Smith, Rachel S. Somerville, Ulrich P. Steinwandel, Romain Teyssier","doi":"arxiv-2409.09121","DOIUrl":"https://doi.org/arxiv-2409.09121","url":null,"abstract":"Traditional star formation subgrid models implemented in cosmological galaxy\u0000formation simulations, such as that of Springel & Hernquist (2003, hereafter\u0000SH03), employ adjustable parameters to satisfy constraints measured in the\u0000local Universe. In recent years, however, theory and spatially-resolved\u0000simulations of the turbulent, multiphase, star-forming ISM have begun to\u0000produce new first-principles models, which when fully developed can replace\u0000traditional subgrid prescriptions. This approach has advantages of being\u0000physically motivated and predictive rather than empirically tuned, and allowing\u0000for varying environmental conditions rather than being tied to local Universe\u0000conditions. As a prototype of this new approach, by combining calibrations from\u0000the TIGRESS numerical framework with the Pressure-Regulated Feedback-Modulated\u0000(PRFM) theory, simple formulae can be obtained for both the gas depletion time\u0000and an effective equation of state. Considering galaxies in TNG50, we compare\u0000the \"native\" simulation outputs with post-processed predictions from PRFM. At\u0000TNG50 resolution, the total midplane pressure is nearly equal to the total ISM\u0000weight, indicating that galaxies in TNG50 are close to satisfying vertical\u0000equilibrium. The measured gas scale height is also close to theoretical\u0000equilibrium predictions. The slopes of the effective equations of states are\u0000similar, but with effective velocity dispersion normalization from SH03\u0000slightly larger than that from current TIGRESS simulations. Because of this and\u0000the decrease in PRFM feedback yield at high pressure, the PRFM model predicts\u0000shorter gas depletion times than the SH03 model at high densities and redshift.\u0000Our results represent a first step towards implementing new, numerically\u0000calibrated subgrid algorithms in cosmological galaxy formation simulations.","PeriodicalId":501207,"journal":{"name":"arXiv - PHYS - Cosmology and Nongalactic Astrophysics","volume":"18 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257673","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Juan Mena-Fernández, Dark Energy Survey Collaboration
Here, we present the angular diameter distance measurement obtained from the measurement of the Baryonic Acoustic Oscillation (BAO) feature using the completed Dark Energy Survey (DES) data, summarizing the main results of [Phys. Rev. D 110, 063514] and [Phys. Rev. D 110, 063515]. We use a galaxy sample optimized for BAO science in the redshift range 0.6 < z < 1.2, with an effective redshift of $z_{rm eff}$ = 0.85. Our consensus measurement constrains the ratio of the angular distance to the sound horizon scale to $D_M(z_{rm eff})/r_d$ = 19.51 $pm$ 0.41. This measurement is found to be 2.13$sigma$ below the angular BAO scale predicted by Planck. To date, it represents the most precise measurement from purely photometric data, and the most precise from any Stage-III experiment at such high redshift. The analysis was performed blinded to the BAO position and is shown to be robust against analysis choices, data removal, redshift calibrations and observational systematics.
在这里，我们介绍利用已完成的暗能量巡天（DES）数据对重子声振荡（BAO）特征进行的角直径距离测量，总结了[Phys.Rev. D 110, 063514]和[Phys.Rev. D 110, 063515]的主要结果。我们使用了一个为BAO科学而优化的星系样本，其红移范围为0.6 < z < 1.2，有效红移为$z_{rm eff}$ = 0.85。我们的共识测量将角距与声层尺度的比值约束为$D_M(z_{/rm eff})/r_d$ = 19.51 $pm$ 0.41。这一测量结果比普朗克预测的BAO角尺度低2.13个西格玛。这是迄今为止通过纯粹的测光数据进行的最精确测量，也是在如此高的红移下通过任何第三阶段实验进行的最精确测量。该分析是在对 BAO 位置保密的情况下进行的，结果表明它对分析选择、数据移除、红移定标和观测系统学都是稳健的。
{"title":"Dark Energy Survey: 2.1% measurement of the Baryon Acoustic Oscillation scale from the final dataset","authors":"Juan Mena-Fernández, Dark Energy Survey Collaboration","doi":"arxiv-2409.08759","DOIUrl":"https://doi.org/arxiv-2409.08759","url":null,"abstract":"Here, we present the angular diameter distance measurement obtained from the\u0000measurement of the Baryonic Acoustic Oscillation (BAO) feature using the\u0000completed Dark Energy Survey (DES) data, summarizing the main results of [Phys.\u0000Rev. D 110, 063514] and [Phys. Rev. D 110, 063515]. We use a galaxy sample\u0000optimized for BAO science in the redshift range 0.6 < z < 1.2, with an\u0000effective redshift of $z_{rm eff}$ = 0.85. Our consensus measurement\u0000constrains the ratio of the angular distance to the sound horizon scale to\u0000$D_M(z_{rm eff})/r_d$ = 19.51 $pm$ 0.41. This measurement is found to be\u00002.13$sigma$ below the angular BAO scale predicted by Planck. To date, it\u0000represents the most precise measurement from purely photometric data, and the\u0000most precise from any Stage-III experiment at such high redshift. The analysis\u0000was performed blinded to the BAO position and is shown to be robust against\u0000analysis choices, data removal, redshift calibrations and observational\u0000systematics.","PeriodicalId":501207,"journal":{"name":"arXiv - PHYS - Cosmology and Nongalactic Astrophysics","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Aims. To investigate the influence of distance to filaments and dark matter halos on galaxy cold gas content in the empirical model NeutralUniverseMachine (NUM) and the hydrodynamical simulation IllustrisTNG. Methods. We use DisPerSE to identify cosmic web structures and calculate the distance of galaxies to filaments for both observations and models. We show the results of the HI and H2 mass functions, HI- and H2-halo mass relations, HI- and H2-stellar mass relations for galaxies in the NUM model and IllustrisTNG with different distances to filaments and compare them with observational measurements. We also show the evolution of HI, H2 mass densities in different distance to filament bins. Results. We find that the role of filaments in affecting the HI gas is generally less significant compared to the halo environment. There is a weak trend in the observations at z = 0 that low-mass halos lying closer to filaments tend to have reduced HI masses. However, this trend reverses for massive halos with log(Mvir/Msun) > 12.5. This behavior is accurately reproduced in the NUM model due to the dependence of HI gas on the halo formation time, but it does not appear in IllustrisTNG. The influence of filaments on the HI gas becomes slightly weaker at higher redshifts and is only significant for galaxies residing in massive halos in the NUM model. Filaments have almost no impact on the H2-stellar mass relation in both models, confirming that H2 is primarily determined by the galaxy stellar mass and star formation rate.
{"title":"NeutralUniverseMachine: How Filaments and Dark Matter Halo Influence the Galaxy Cold Gas Content","authors":"Wenlin Ma, Hong Guo, Michael G. Jones","doi":"arxiv-2409.08539","DOIUrl":"https://doi.org/arxiv-2409.08539","url":null,"abstract":"Aims. To investigate the influence of distance to filaments and dark matter\u0000halos on galaxy cold gas content in the empirical model NeutralUniverseMachine\u0000(NUM) and the hydrodynamical simulation IllustrisTNG. Methods. We use DisPerSE\u0000to identify cosmic web structures and calculate the distance of galaxies to\u0000filaments for both observations and models. We show the results of the HI and\u0000H2 mass functions, HI- and H2-halo mass relations, HI- and H2-stellar mass\u0000relations for galaxies in the NUM model and IllustrisTNG with different\u0000distances to filaments and compare them with observational measurements. We\u0000also show the evolution of HI, H2 mass densities in different distance to\u0000filament bins. Results. We find that the role of filaments in affecting the HI\u0000gas is generally less significant compared to the halo environment. There is a\u0000weak trend in the observations at z = 0 that low-mass halos lying closer to\u0000filaments tend to have reduced HI masses. However, this trend reverses for\u0000massive halos with log(Mvir/Msun) > 12.5. This behavior is accurately\u0000reproduced in the NUM model due to the dependence of HI gas on the halo\u0000formation time, but it does not appear in IllustrisTNG. The influence of\u0000filaments on the HI gas becomes slightly weaker at higher redshifts and is only\u0000significant for galaxies residing in massive halos in the NUM model. Filaments\u0000have almost no impact on the H2-stellar mass relation in both models,\u0000confirming that H2 is primarily determined by the galaxy stellar mass and star\u0000formation rate.","PeriodicalId":501207,"journal":{"name":"arXiv - PHYS - Cosmology and Nongalactic Astrophysics","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257679","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A new inflationary scenario driven by a slowly-rolling homogeneous scalar field whose potential $Vleft(varphiright)$ is given by a generalized exponential function is investigated. Within the {it slow-roll} approximation we obtain the main predictions of the model and compare them with current data from cosmic microwave background and large-scale structure observations. We show that this single scalar field model admits a wider set of solutions than usual exponential scenarios and predicts acceptable values of the spectral index, running of the spectral index and tensor-to-scalar ratio for the remaining number of {it e}-folds lying in the interval $N = 55 pm 5$ and an energy scale on which $lambda geq sqrt{2}$; in particular, we observe that the value of the model parameter $kappa$ depends on the analysis. Finally, the primordial local non-Gaussianity is briefly discussed where we conclude that $kgtrsim 0.02$ for $f_text{NL}^text{local} ll 1$.
{"title":"Generalized inflation in the context of $κ$-deformed theories","authors":"B W Ribeiro, I M Macêdo, F C Cabral","doi":"arxiv-2409.07678","DOIUrl":"https://doi.org/arxiv-2409.07678","url":null,"abstract":"A new inflationary scenario driven by a slowly-rolling homogeneous scalar\u0000field whose potential $Vleft(varphiright)$ is given by a generalized\u0000exponential function is investigated. Within the {it slow-roll} approximation\u0000we obtain the main predictions of the model and compare them with current data\u0000from cosmic microwave background and large-scale structure observations. We\u0000show that this single scalar field model admits a wider set of solutions than\u0000usual exponential scenarios and predicts acceptable values of the spectral\u0000index, running of the spectral index and tensor-to-scalar ratio for the\u0000remaining number of {it e}-folds lying in the interval $N = 55 pm 5$ and an\u0000energy scale on which $lambda geq sqrt{2}$; in particular, we observe that\u0000the value of the model parameter $kappa$ depends on the analysis. Finally, the\u0000primordial local non-Gaussianity is briefly discussed where we conclude that\u0000$kgtrsim 0.02$ for $f_text{NL}^text{local} ll 1$.","PeriodicalId":501207,"journal":{"name":"arXiv - PHYS - Cosmology and Nongalactic Astrophysics","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142192768","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lea Harscouet, Jessica A. Cowell, Julia Ereza, David Alonso, Hugo Camacho, Andrina Nicola, Anze Slosar
The study of third-order statistics in large-scale structure analyses has been hampered by the increased complexity of bispectrum estimators (compared to power spectra), the large dimensionality of the data vector, and the difficulty in estimating its covariance matrix. In this paper we present the filtered-squared bispectrum (FSB), an estimator of the projected bispectrum effectively consisting of the cross-correlation between the square of a field filtered on a range of scales and the original field. Within this formalism, we are able to recycle much of the infrastructure built around power spectrum measurement to construct an estimator that is both fast and robust against mode-coupling effects caused by incomplete sky observations. Furthermore, we demonstrate that the existing techniques for the estimation of analytical power spectrum covariances can be used within this formalism to calculate the bispectrum covariance at very high accuracy, naturally accounting for the most relevant Gaussian and non-Gaussian contributions in a model-independent manner.
{"title":"Fast Projected Bispectra: the filter-square approach","authors":"Lea Harscouet, Jessica A. Cowell, Julia Ereza, David Alonso, Hugo Camacho, Andrina Nicola, Anze Slosar","doi":"arxiv-2409.07980","DOIUrl":"https://doi.org/arxiv-2409.07980","url":null,"abstract":"The study of third-order statistics in large-scale structure analyses has\u0000been hampered by the increased complexity of bispectrum estimators (compared to\u0000power spectra), the large dimensionality of the data vector, and the difficulty\u0000in estimating its covariance matrix. In this paper we present the\u0000filtered-squared bispectrum (FSB), an estimator of the projected bispectrum\u0000effectively consisting of the cross-correlation between the square of a field\u0000filtered on a range of scales and the original field. Within this formalism, we\u0000are able to recycle much of the infrastructure built around power spectrum\u0000measurement to construct an estimator that is both fast and robust against\u0000mode-coupling effects caused by incomplete sky observations. Furthermore, we\u0000demonstrate that the existing techniques for the estimation of analytical power\u0000spectrum covariances can be used within this formalism to calculate the\u0000bispectrum covariance at very high accuracy, naturally accounting for the most\u0000relevant Gaussian and non-Gaussian contributions in a model-independent manner.","PeriodicalId":501207,"journal":{"name":"arXiv - PHYS - Cosmology and Nongalactic Astrophysics","volume":"132 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142192766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pranjal R. S., Eric Huff, Elisabeth Krause, Tim Eifler, Spencer Everett, Yu-Hsiu Huang, Jiachuan Xu
We present the first detection of a cluster lensing signal with `Kinematic Lensing' (KL), a novel weak lensing method that combines photometry, spectroscopy, and the Tully-Fisher relation to enable shear measurements with individual source galaxies. This is the second paper in a two-part series aimed at measuring a KL signal from data. The first paper, arXiv:2209.11811, describes the inference pipeline, which jointly forward models galaxy imaging and spectroscopy, and demonstrates unbiased shear inference with simulated data. This paper presents measurements of the lensing signal from the galaxy cluster Abell 2261. We obtain spectroscopic observations of background disk galaxies in the cluster field selected from the CLASH Subaru catalog. The final sample consists of three source galaxies while the remaining are rejected due to insufficient signal-to-noise, spectroscopic failures, and inadequately sampled rotation curves. We apply the KL inference pipeline to the three sources and find the shear estimates to be in broad agreement with traditional weak lensing measurements. The typical shear measurement uncertainty for our sources is $sigma(g_+)approx 0.026$, which represents approximately a ten-fold improvement over the weak lensing shape noise. We identify target selection and observing strategy as the key avenues of improvement for future KL programs.
{"title":"Kinematic Lensing Inference II: Cluster Lensing with $mathcal{O}$(1) Galaxies","authors":"Pranjal R. S., Eric Huff, Elisabeth Krause, Tim Eifler, Spencer Everett, Yu-Hsiu Huang, Jiachuan Xu","doi":"arxiv-2409.08367","DOIUrl":"https://doi.org/arxiv-2409.08367","url":null,"abstract":"We present the first detection of a cluster lensing signal with `Kinematic\u0000Lensing' (KL), a novel weak lensing method that combines photometry,\u0000spectroscopy, and the Tully-Fisher relation to enable shear measurements with\u0000individual source galaxies. This is the second paper in a two-part series aimed\u0000at measuring a KL signal from data. The first paper, arXiv:2209.11811,\u0000describes the inference pipeline, which jointly forward models galaxy imaging\u0000and spectroscopy, and demonstrates unbiased shear inference with simulated\u0000data. This paper presents measurements of the lensing signal from the galaxy\u0000cluster Abell 2261. We obtain spectroscopic observations of background disk\u0000galaxies in the cluster field selected from the CLASH Subaru catalog. The final\u0000sample consists of three source galaxies while the remaining are rejected due\u0000to insufficient signal-to-noise, spectroscopic failures, and inadequately\u0000sampled rotation curves. We apply the KL inference pipeline to the three\u0000sources and find the shear estimates to be in broad agreement with traditional\u0000weak lensing measurements. The typical shear measurement uncertainty for our\u0000sources is $sigma(g_+)approx 0.026$, which represents approximately a\u0000ten-fold improvement over the weak lensing shape noise. We identify target\u0000selection and observing strategy as the key avenues of improvement for future\u0000KL programs.","PeriodicalId":501207,"journal":{"name":"arXiv - PHYS - Cosmology and Nongalactic Astrophysics","volume":"31 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Joey Braspenning, Joop Schaye, Matthieu Schaller, Roi Kugel, Scott T. Kay
The masses of galaxy clusters are commonly measured from X-ray observations under the assumption of hydrostatic equilibrium (HSE). This technique is known to underestimate the true mass systematically. The fiducial FLAMINGO cosmological hydrodynamical simulation predicts the median hydrostatic mass bias to increase from $b_text{HSE} equiv (M_text{HSE,500c}-M_text{500c})/M_text{500c} approx -0.1$ to -0.2 when the true mass increases from group to cluster mass scales. However, the bias is nearly independent of the hydrostatic mass. The scatter at fixed true mass is minimum for $M_text{500c}sim 10^{14}~text{M}_odot$, where $sigma(b_text{HSE})approx 0.1$, but increases rapidly towards lower and higher masses. At a fixed true mass, the hydrostatic masses increase (decrease) with redshift on group (cluster) scales, and the scatter increases. The bias is insensitive to the choice of analytic functions assumed to represent the density and temperature profiles, but it is sensitive to the goodness of fit, with poorer fits corresponding to a stronger median bias and a larger scatter. The bias is also sensitive to the strength of stellar and AGN feedback. Models predicting lower gas fractions yield more (less) biased masses for groups (clusters). The scatter in the bias at fixed true mass is due to differences in the pressure gradients rather than in the temperature at $R_text{500c}$. The total kinetic energies within $r_text{500c}$ in low- and high-mass clusters are sub- and super-virial, respectively, though all become sub-virial when external pressure is accounted for. Analyses of the terms in the virial and Euler equations suggest that non-thermal motions, including rotation, account for most of the hydrostatic mass bias. However, we find that the mass bias estimated from X-ray luminosity weighted profiles strongly overestimates the deviations from hydrostatic equilibrium.
星系团的质量通常是在静水平衡（HSE）假设下通过 X 射线观测测得的。众所周知，这种技术系统地低估了真实质量。根据FLAMINGO宇宙学流体力学模拟的预测，中位静水质量偏差将从$b_text{HSE}增加到$m_text{HSE}。equiv(M_text{HSE,500c}-M_text{500c})/M_text{500c}当真实质量从群体质量尺度增加到星团质量尺度时，偏差约为-0.1$到-0.2$。然而，偏差几乎与静水质量无关。固定真实质量下的散度在$M_text{500c}sim 10^{14}~text{M}_odot$ 时最小，此时$sigma(b_text{HSE})approx 0.1$，但随着质量的降低和提高，散度迅速增大。在固定的真实质量下，流体静力学质量随着群（星团）尺度的红移而增加（减少），散度也随之增加。偏差对所假定的表示密度和温度剖面的解析函数的选择并不敏感，但它对拟合的好坏也很敏感，拟合得越差，中值偏差越大，散度也越大。预测气体比例较低的模型会产生较多（较少）的群（星团）质量偏差。在真实质量固定的情况下，偏差的散布是由于压力梯度的不同而不是R_text{500c}$温度的不同造成的。低质量和高质量星团在$r_text{500c}$范围内的总动能分别是亚漩涡和超漩涡的，尽管在考虑了外部压力后都变成了亚漩涡。对virial方程和Euler方程中的项的分析表明，包括旋转在内的非热运动是静水质量偏差的主要原因。然而，我们发现根据 X 射线光度加权剖面估算出的质量偏差严重高估了流体静力学平衡的偏差。
{"title":"Hydrostatic mass bias for galaxy groups and clusters in the FLAMINGO simulations","authors":"Joey Braspenning, Joop Schaye, Matthieu Schaller, Roi Kugel, Scott T. Kay","doi":"arxiv-2409.07849","DOIUrl":"https://doi.org/arxiv-2409.07849","url":null,"abstract":"The masses of galaxy clusters are commonly measured from X-ray observations\u0000under the assumption of hydrostatic equilibrium (HSE). This technique is known\u0000to underestimate the true mass systematically. The fiducial FLAMINGO\u0000cosmological hydrodynamical simulation predicts the median hydrostatic mass\u0000bias to increase from $b_text{HSE} equiv\u0000(M_text{HSE,500c}-M_text{500c})/M_text{500c} approx -0.1$ to -0.2 when the\u0000true mass increases from group to cluster mass scales. However, the bias is\u0000nearly independent of the hydrostatic mass. The scatter at fixed true mass is\u0000minimum for $M_text{500c}sim 10^{14}~text{M}_odot$, where\u0000$sigma(b_text{HSE})approx 0.1$, but increases rapidly towards lower and\u0000higher masses. At a fixed true mass, the hydrostatic masses increase (decrease)\u0000with redshift on group (cluster) scales, and the scatter increases. The bias is\u0000insensitive to the choice of analytic functions assumed to represent the\u0000density and temperature profiles, but it is sensitive to the goodness of fit,\u0000with poorer fits corresponding to a stronger median bias and a larger scatter.\u0000The bias is also sensitive to the strength of stellar and AGN feedback. Models\u0000predicting lower gas fractions yield more (less) biased masses for groups\u0000(clusters). The scatter in the bias at fixed true mass is due to differences in\u0000the pressure gradients rather than in the temperature at $R_text{500c}$. The\u0000total kinetic energies within $r_text{500c}$ in low- and high-mass clusters\u0000are sub- and super-virial, respectively, though all become sub-virial when\u0000external pressure is accounted for. Analyses of the terms in the virial and\u0000Euler equations suggest that non-thermal motions, including rotation, account\u0000for most of the hydrostatic mass bias. However, we find that the mass bias\u0000estimated from X-ray luminosity weighted profiles strongly overestimates the\u0000deviations from hydrostatic equilibrium.","PeriodicalId":501207,"journal":{"name":"arXiv - PHYS - Cosmology and Nongalactic Astrophysics","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142192767","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The escaping ionising efficiency from galaxies, $f_{rm esc}xi_{rm ion}$, is a crucial ingredient for understanding their contribution to hydrogen reionisation, but both of its components, $f_{rm{esc}}$ and $xi_{rm{ion}}$, are extremely difficult to measure. We measure the average escaping ionising efficiency $langle f_{rm{esc}} xi_{rm{ion}}rangle$ of galaxies at $z=5$ implied by the mean level of ionisation in the intergalactic medium via the Lyman-$alpha$ forest. We use the fact that $dot{N}_{rm{ion}} = rho_{rm{UV}} f_{rm{esc}} xi_{rm{ion}}$, the product of the ionising output and the UV density $rho_{rm{UV}}$, can be calculated from the known average strength of the UV background and the mean free path of ionising photons. These quantities, as well as $rho_{rm{UV}}$, are robustly measured at $zleq6$. We calculate the missing factor of $langle f_{rm{esc}} xi_{rm{ion}}rangle$ at $z=5$, during a convenient epoch after hydrogen reionisation has completed and the intergalactic medium has reached ionisation equilibrium, but before bright quasars begin to dominate the ionising photon production. Intuitively, our constraint corresponds to the required escaping ionising production from galaxies in order to avoid over- or under-ionising the Lyman-$alpha$ forest. We obtain a measurement of $log langle f_{rm{esc}} xi_{rm{ion}}rangle /$erg Hz$^{-1}$ $ = 24.28_{-0.20}^{+0.21}$ at $z=5$ when integrating $rho_text{UV}$ down to a limiting magnitude $M_text{lim}=-11$. Our measurement of the escaping ionising efficiency of galaxies is in rough agreement with both observations and most models.
{"title":"A measurement of the escaping ionising efficiency of galaxies at redshift 5","authors":"Sarah E. I. Bosman, Frederick B. Davies","doi":"arxiv-2409.08315","DOIUrl":"https://doi.org/arxiv-2409.08315","url":null,"abstract":"The escaping ionising efficiency from galaxies, $f_{rm esc}xi_{rm ion}$,\u0000is a crucial ingredient for understanding their contribution to hydrogen\u0000reionisation, but both of its components, $f_{rm{esc}}$ and $xi_{rm{ion}}$,\u0000are extremely difficult to measure. We measure the average escaping ionising\u0000efficiency $langle f_{rm{esc}} xi_{rm{ion}}rangle$ of galaxies at $z=5$\u0000implied by the mean level of ionisation in the intergalactic medium via the\u0000Lyman-$alpha$ forest. We use the fact that $dot{N}_{rm{ion}} =\u0000rho_{rm{UV}} f_{rm{esc}} xi_{rm{ion}}$, the product of the ionising output\u0000and the UV density $rho_{rm{UV}}$, can be calculated from the known average\u0000strength of the UV background and the mean free path of ionising photons. These\u0000quantities, as well as $rho_{rm{UV}}$, are robustly measured at $zleq6$. We\u0000calculate the missing factor of $langle f_{rm{esc}} xi_{rm{ion}}rangle$ at\u0000$z=5$, during a convenient epoch after hydrogen reionisation has completed and\u0000the intergalactic medium has reached ionisation equilibrium, but before bright\u0000quasars begin to dominate the ionising photon production. Intuitively, our\u0000constraint corresponds to the required escaping ionising production from\u0000galaxies in order to avoid over- or under-ionising the Lyman-$alpha$ forest.\u0000We obtain a measurement of $log langle f_{rm{esc}} xi_{rm{ion}}rangle\u0000/$erg Hz$^{-1}$ $ = 24.28_{-0.20}^{+0.21}$ at $z=5$ when integrating\u0000$rho_text{UV}$ down to a limiting magnitude $M_text{lim}=-11$. Our\u0000measurement of the escaping ionising efficiency of galaxies is in rough\u0000agreement with both observations and most models.","PeriodicalId":501207,"journal":{"name":"arXiv - PHYS - Cosmology and Nongalactic Astrophysics","volume":"188 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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