ORCID Profile
0000-0003-0467-5438
Current Organisation
The University of Edinburgh
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Publisher: Oxford University Press (OUP)
Date: 30-09-2016
Publisher: Oxford University Press (OUP)
Date: 21-07-2014
Publisher: Oxford University Press (OUP)
Date: 11-04-2017
DOI: 10.1093/MNRAS/STX883
Publisher: Oxford University Press (OUP)
Date: 18-05-2023
Abstract: We report a new test of modified gravity theories using the large-scale structure of the Universe. This paper is the first attempt to (1) apply a joint analysis of the anisotropic components of galaxy two- and three-point correlation functions (2 and 3PCFs) to actual galaxy data and (2) constrain the non-linear effects of degenerate higher-order scalar-tensor (DHOST) theories on cosmological scales. Applying this analysis to the Baryon Oscillation Spectroscopic Survey (BOSS) data release 12, we obtain the lower bounds of −1.655 & ξt and −0.504 & ξs at the $95{{\\ \\rm per\\ cent}}$ confidence level on the parameters characterizing the time evolution of the tidal and shift terms of the second-order velocity field. These constraints are consistent with GR predictions of ξt = 15/1144 and ξs = 0. Moreover, they represent a 35-fold and 20-fold improvement, respectively, over the joint analysis with only the isotropic 3PCF. We ensure the validity of our results by investigating various quantities, including theoretical models of the 3PCF, window function corrections, cumulative S/N, Fisher matrices, and statistical scattering effects of mock simulation data. We also find statistically significant discrepancies between the BOSS data and the Patchy mocks for the 3PCF measurement. Finally, we package all of our 3PCF analysis codes under the name hitomi and make them publicly available so that readers can reproduce all the results of this paper and easily apply them to ongoing future galaxy surveys.
Publisher: American Physical Society (APS)
Date: 27-12-2019
Publisher: Oxford University Press (OUP)
Date: 28-09-2023
Publisher: Oxford University Press (OUP)
Date: 04-04-2014
DOI: 10.1093/MNRAS/STU371
Publisher: Oxford University Press (OUP)
Date: 17-08-2022
Abstract: We introduce preconditioned Monte Carlo (PMC), a novel Monte Carlo method for Bayesian inference that facilitates efficient s ling of probability distributions with non-trivial geometry. PMC utilizes a Normalizing Flow (NF) in order to decorrelate the parameters of the distribution and then proceeds by s ling from the preconditioned target distribution using an adaptive Sequential Monte Carlo (SMC) scheme. The results produced by PMC include s les from the posterior distribution and an estimate of the model evidence that can be used for parameter inference and model comparison, respectively. The aforementioned framework has been thoroughly tested in a variety of challenging target distributions achieving state-of-the-art s ling performance. In the cases of primordial feature analysis and gravitational wave inference, PMC is approximately 50 and 25 times faster, respectively, than nested s ling (NS). We found that in higher dimensional applications, the acceleration is even greater. Finally, PMC is directly parallelisable, manifesting linear scaling up to thousands of CPUs.
Publisher: Oxford University Press (OUP)
Date: 15-03-2018
DOI: 10.1093/MNRAS/STY571
Publisher: Oxford University Press (OUP)
Date: 30-06-2017
Publisher: American Astronomical Society
Date: 18-09-2018
Publisher: American Physical Society (APS)
Date: 16-06-2023
Publisher: Oxford University Press (OUP)
Date: 16-11-2022
Abstract: In this paper, we present an extension to the matryoshka suite of neural-network-based emulators. The new editions have been developed to accelerate effective field theory of large-scale structure (EFTofLSS) analyses of galaxy power spectrum multipoles in redshift space. They are collectively referred to as the EFTEMU. We test the EFTEMU at the power spectrum level and achieve a prediction accuracy of better than 1 per cent with BOSS-like bias parameters and counterterms on scales 0.001 ≤ k ≤ 0.19 h Mpc−1. We also run a series of mock full-shape analyses to test the performance of the EFTEMU when carrying out parameter inference. Through these mock analyses, we verify that the EFTEMU recovers the true cosmology within 1σ at several redshifts (z = [0.38, 0.51, 0.61]), and with several noise levels (the most stringent of which is Gaussian covariance associated with a volume of 50003 Mpc3 h−3). We compare the mock inference results from the EFTEMU to those obtained with a fully analytic EFTofLSS model and again find no significant bias, whilst speeding up the inference by three orders of magnitude. The EFTEMU is publicly available as part of the matryoshkaPython package.
Publisher: American Astronomical Society
Date: 20-10-2022
Abstract: The Dark Energy Spectroscopic Instrument (DESI) embarked on an ambitious 5 yr survey in 2021 May to explore the nature of dark energy with spectroscopic measurements of 40 million galaxies and quasars. DESI will determine precise redshifts and employ the baryon acoustic oscillation method to measure distances from the nearby universe to beyond redshift z 3.5, and employ redshift space distortions to measure the growth of structure and probe potential modifications to general relativity. We describe the significant instrumentation we developed to conduct the DESI survey. This includes: a wide-field, 3.°2 diameter prime-focus corrector a focal plane system with 5020 fiber positioners on the 0.812 m diameter, aspheric focal surface 10 continuous, high-efficiency fiber cable bundles that connect the focal plane to the spectrographs and 10 identical spectrographs. Each spectrograph employs a pair of dichroics to split the light into three channels that together record the light from 360–980 nm with a spectral resolution that ranges from 2000–5000. We describe the science requirements, their connection to the technical requirements, the management of the project, and interfaces between subsystems. DESI was installed at the 4 m Mayall Telescope at Kitt Peak National Observatory and has achieved all of its performance goals. Some performance highlights include an rms positioner accuracy of better than 0.″1 and a median signal-to-noise ratio of 7 of the [O ii ] doublet at 8 × 10 −17 erg s −1 cm −2 in 1000 s for galaxies at z = 1.4–1.6. We conclude with additional highlights from the on-sky validation and commissioning, key successes, and lessons learned.
Publisher: The Open Journal
Date: 09-11-2022
DOI: 10.21105/JOSS.04634
Publisher: Oxford University Press (OUP)
Date: 18-03-2020
Abstract: Standard analysis pipelines for measurements of Baryon Acoustic Oscillations (BAO) in galaxy surveys make use of a fiducial cosmological model to guide the data compression required to transform from observed redshifts and angles to the measured angular and radial BAO peak positions. In order to remove any dependence on the fiducial cosmology from the results, all models compared to the data should mimic the compression and its dependence on the fiducial model. In practice, approximations are made when testing models: (1) There is assumed to be no residual dependence on the fiducial cosmology after reconstruction, (2) differences in the distance–redshift relationship are assumed to match a linear scaling, and (3) differences in clustering between true and fiducial models are assumed to be removed by the free parameters used to null the non-BAO signal. We test these approximations using the current standard measurement procedure with a set of halo catalogues from the aemulus suite of N-body simulations, which span a range of wCDM cosmological models. We focus on reconstruction of the primordial BAO and locating the BAO. For the range of wCDM cosmologies covered by the aemulus suite, we find no evidence for systematic errors in the measured BAO shift parameters α∥ and α⊥ to $\\lt 0.1\\%$. However, the measured errors $\\sigma _{\\alpha _{\\parallel }}$ and $\\sigma _{\\alpha _{\\bot }}$ show a notable absolute increase by up to +0.001 and +0.002, respectively, in the case that the fiducial cosmology does not match the truth. These effects on the inferred BAO scale will be important, given the precision of measurements expected from future surveys including DESI, Euclid, and WFIRST.
Publisher: Oxford University Press (OUP)
Date: 12-01-2013
DOI: 10.1093/MNRAS/STS637
Publisher: IOP Publishing
Date: 26-03-2019
Publisher: American Astronomical Society
Date: 25-06-2020
Abstract: This paper documents the 16th data release (DR16) from the Sloan Digital Sky Surveys (SDSS), the fourth and penultimate from the fourth phase (SDSS-IV). This is the first release of data from the Southern Hemisphere survey of the Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) new data from APOGEE-2 North are also included. DR16 is also notable as the final data release for the main cosmological program of the Extended Baryon Oscillation Spectroscopic Survey (eBOSS), and all raw and reduced spectra from that project are released here. DR16 also includes all the data from the Time Domain Spectroscopic Survey and new data from the SPectroscopic IDentification of ERosita Survey programs, both of which were co-observed on eBOSS plates. DR16 has no new data from the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey (or the MaNGA Stellar Library “MaStar”). We also preview future SDSS-V operations (due to start in 2020), and summarize plans for the final SDSS-IV data release (DR17).
Publisher: Elsevier BV
Date: 05-2009
Publisher: American Astronomical Society
Date: 29-06-2017
Publisher: American Physical Society (APS)
Date: 04-04-2017
Publisher: Cambridge University Press (CUP)
Date: 08-2012
DOI: 10.1017/S1743921312021618
Abstract: Baryon acoustic oscillations (BAO) at low redshift provide a precise and largely model-independent way to measure the Hubble constant, H 0 . The 6dF Galaxy Survey measurement of the BAO scale gives a value of H 0 = 67 ± 3.2 km s −1 Mpc −1 , achieving a 1σ precision of 5%. With improved analysis techniques, the planned wallaby (H i ) and taipan (optical) redshift surveys are predicted to measure H 0 to 1–3% precision.
Publisher: Oxford University Press (OUP)
Date: 30-09-2020
Abstract: Relativistic effects in clustering observations have been shown to introduce scale-dependent corrections to the galaxy overdensity field on large scales, which may h er the detection of primordial non-Gaussianity fNL through the scale-dependent halo bias. The litude of relativistic corrections depends not only on the cosmological background expansion, but also on the redshift evolution and sensitivity to the luminosity threshold of the tracer population being examined, as parametrized by the evolution bias be and magnification bias s. In this work, we propagate luminosity function measurements from the extended Baryon Oscillation Spectroscopic Survey (eBOSS) to be and s for the quasar (QSO) s le, and thereby derive constraints on relativistic corrections to its power spectrum multipoles. Although one could mitigate the impact on the fNL signature by adjusting the redshift range or the luminosity threshold of the tracer s le being considered, we suggest that, for future surveys probing large cosmic volumes, relativistic corrections should be forward modelled from the tracer luminosity function including its uncertainties. This will be important to quasar clustering measurements on scales $k \\sim 10^{-3}\\, h\\, {\\rm Mpc}^{-1}$ in upcoming surveys such as the Dark Energy Spectroscopic Instrument (DESI), where relativistic corrections can overwhelm the expected fNL signature at low redshifts z ≲ 1 and become comparable to fNL ≃ 1 in the power spectrum quadrupole at redshifts z ≳ 2.5.
Publisher: Oxford University Press (OUP)
Date: 10-12-2016
Publisher: Oxford University Press (OUP)
Date: 06-07-2020
Abstract: In this paper, we predict the covariance matrices of both the power spectrum and the bispectrum, including full non-Gaussian contributions, redshift space distortions, linear bias effects, and shot-noise corrections, using perturbation theory (PT). To quantify the redshift-space distortion effect, we focus mainly on the monopole and quadrupole components of both the power and bispectra. We, for the first time, compute the 5- and 6-point spectra to predict the cross-covariance between the power and bispectra, and the autocovariance of the bispectrum in redshift space. We test the validity of our calculations by comparing them with the covariance matrices measured from the MultiDark-Patchy mock catalogues that are designed to reproduce the galaxy clustering measured from the Baryon Oscillation Spectroscopic Survey Data Release 12. We argue that the simple, leading-order PT works because the shot-noise corrections for the Patchy mocks are more dominant than other higher order terms we ignore. In the meantime, we confirm some discrepancies in the comparison, especially of the cross-covariance. We discuss potential sources of such discrepancies. We also show that our PT model reproduces well the cumulative signal-to-noise ratio of the power spectrum and the bispectrum as a function of maximum wavenumber, implying that our PT model captures successfully essential contributions to the covariance matrices.
Publisher: Oxford University Press (OUP)
Date: 03-12-2020
Abstract: We establish a practical method for the joint analysis of anisotropic galaxy two- and three-point correlation functions (2PCF and 3PCF, respectively) on the basis of the decomposition formalism of the 3PCF using tripolar spherical harmonics. We perform such an analysis with MultiDark-Patchy mock catalogues to demonstrate and understand the benefit of the anisotropic 3PCF. We focus on scales above $80\\, h^{-1}\\, {\\rm Mpc}$, and use information from the shape and the baryon acoustic oscillation (BAO) signals of the 2PCF and 3PCF. We also apply density field reconstruction to increase the signal-to-noise ratio of BAO in the 2PCF measurement, but not in the 3PCF measurement. In particular, we study in detail the constraints on the angular diameter distance and the Hubble parameter. We build a model of the bispectrum or 3PCF that includes the non-linear d ing of the BAO signal in redshift space. We carefully account for various uncertainties in our analysis including theoretical models of the 3PCF, window function corrections, biases in estimated parameters from the fiducial values, the number of mock realizations to estimate the covariance matrix, and bin size. The joint analysis of the 2PCF and 3PCF monopole and quadrupole components shows a $30{{\\ \\rm per\\ cent}}$ and $20{{\\ \\rm per\\ cent}}$ improvement in Hubble parameter constraints before and after reconstruction of the 2PCF measurements, respectively, compared to the 2PCF analysis alone. This study clearly shows that the anisotropic 3PCF increases cosmological information from galaxy surveys and encourages further development of the modelling of the 3PCF on smaller scales than we consider.
Publisher: Springer Science and Business Media LLC
Date: 28-08-2017
Publisher: Oxford University Press (OUP)
Date: 07-02-2017
Publisher: Oxford University Press (OUP)
Date: 23-01-2017
DOI: 10.1093/MNRAS/STX178
Publisher: Oxford University Press (OUP)
Date: 13-05-2016
Publisher: Oxford University Press (OUP)
Date: 26-06-2016
Publisher: Oxford University Press (OUP)
Date: 17-09-2014
Publisher: American Physical Society (APS)
Date: 02-12-2021
Publisher: American Physical Society (APS)
Date: 18-12-2015
Publisher: Oxford University Press (OUP)
Date: 09-01-2018
Publisher: Oxford University Press (OUP)
Date: 30-01-2014
Publisher: American Astronomical Society
Date: 11-04-2019
Publisher: Springer Science and Business Media LLC
Date: 25-02-2019
Publisher: Oxford University Press (OUP)
Date: 05-10-2021
Abstract: We introduce zeus, a well-tested Python implementation of the Ensemble Slice S ling (ESS) method for Bayesian parameter inference. ESS is a novel Markov chain Monte Carlo (MCMC) algorithm specifically designed to tackle the computational challenges posed by modern astronomical and cosmological analyses. In particular, the method requires only minimal hand-tuning of 1−2 hyperparameters that are often trivial to set its performance is insensitive to linear correlations and it can scale up to 1000s of CPUs without any extra effort. Furthermore, its locally adaptive nature allows to s le efficiently even when strong non-linear correlations are present. Lastly, the method achieves a high performance even in strongly multimodal distributions in high dimensions. Compared to emcee, a popular MCMC s ler, zeus performs 9 and 29 times better in a cosmological and an exoplanet application, respectively.
Publisher: Oxford University Press (OUP)
Date: 30-05-2018
Publisher: American Astronomical Society
Date: 04-02-2016
Publisher: Oxford University Press (OUP)
Date: 09-04-2014
DOI: 10.1093/MNRAS/STU342
Publisher: Oxford University Press (OUP)
Date: 26-11-2015
Publisher: Oxford University Press (OUP)
Date: 20-12-2018
Publisher: Oxford University Press (OUP)
Date: 05-04-2016
DOI: 10.1093/MNRAS/STW763
Publisher: Oxford University Press (OUP)
Date: 26-02-2019
DOI: 10.1093/MNRAS/STZ558
Publisher: Oxford University Press (OUP)
Date: 27-02-2014
DOI: 10.1093/MNRAS/STU197
Publisher: American Physical Society (APS)
Date: 30-10-2017
Publisher: Oxford University Press (OUP)
Date: 28-01-2022
Abstract: The density field reconstruction technique has been widely used for recovering the baryon acoustic oscillation (BAO) feature in galaxy surveys that has been degraded due to non-linearities. Recent studies advocated adopting iterative steps to improve the recovery much beyond that of the standard technique. In this paper, we investigate the performance of a few selected iterative reconstruction techniques focusing on the BAO and the broad-band shape of the two-point clustering. We include redshift-space distortions, halo bias, and shot noise and inspect the components of the reconstructed field in Fourier space and in configuration space using both density field-based reconstruction and displacement field-based reconstruction. We find that the displacement field reconstruction becomes quickly challenging in the presence of non-negligible shot noise and therefore present surrogate methods that can be practically applied to a much more sparse field such as galaxies. For a galaxy field, implementing a debiasing step to remove the Lagrangian bias appears crucial for the displacement field reconstruction. We show that the iterative reconstruction does not substantially improve the BAO feature beyond an aggressively optimized standard reconstruction with a small smoothing kernel. However, we find taking iterative steps allows us to use a small smoothing kernel more ‘stably’, i.e. without causing a substantial deviation from the linear power spectrum on large scales. In one specific ex le we studied, we find that a deviation of 13 per cent in $P(k\\sim 0.1\\, h{\\rm \\,\\,Mpc^{-1}})$ with an aggressive standard reconstruction can reduce to 3–4 per cent with iterative steps.
Publisher: American Physical Society (APS)
Date: 14-12-2015
Publisher: Oxford University Press (OUP)
Date: 11-10-2017
Publisher: Oxford University Press (OUP)
Date: 17-12-2020
Abstract: We analyse the large-scale clustering in Fourier space of emission line galaxies (ELG) from the Data Release 16 of the Sloan Digital Sky Survey IV extended Baryon Oscillation Spectroscopic Survey. The ELG s le contains 173,736 galaxies covering 1,170 square degrees in the redshift range 0.6 & z & 1.1. We perform a BAO measurement from the post-reconstruction power spectrum monopole, and study redshift space distortions (RSD) in the first three even multipoles. Photometric variations yield fluctuations of both the angular and radial survey selection functions. Those are directly inferred from data, imposing integral constraints which we model consistently. The full data set has only a weak preference for a BAO feature (1.4σ). At the effective redshift zeff = 0.845 we measure $D_{\\rm V}(z_{\\rm eff})/r_{\\rm drag} = 18.33_{-0.62}^{+0.57}$, with DV the volume-averaged distance and rdrag the comoving sound horizon at the drag epoch. In combination with the RSD measurement, at zeff = 0.85 we find $f\\sigma _8(z_{\\rm eff}) = 0.289_{-0.096}^{+0.085}$, with f the growth rate of structure and σ8 the normalisation of the linear power spectrum, $D_{\\rm H}(z_{\\rm eff})/r_{\\rm drag} = 20.0_{-2.2}^{+2.4}$ and DM(zeff)/rdrag = 19.17 ± 0.99 with DH and DM the Hubble and comoving angular distances, respectively. These results are in agreement with those obtained in configuration space, thus allowing a consensus measurement of fσ8(zeff) = 0.315 ± 0.095, $D_{\\rm H}(z_{\\rm eff})/r_{\\rm drag} = 19.6_{-2.1}^{+2.2}$ and DM(zeff)/rdrag = 19.5 ± 1.0. This measurement is consistent with a flat ΛCDM model with Planck parameters.
Publisher: Oxford University Press (OUP)
Date: 25-07-2011
Publisher: Oxford University Press (OUP)
Date: 29-01-2022
Abstract: We present matryoshka, a suite of neural-network-based emulators and accompanying python package that have been developed with the goal of producing fast and accurate predictions of the non-linear galaxy power spectrum. The suite of emulators consists of four linear component emulators, from which fast linear predictions of the power spectrum can be made, allowing all non-linearities to be included in predictions from a non-linear boost component emulator. The linear component emulators include an emulator for the matter transfer function that produces predictions in ∼0.0004 s, with an error of ${\\lt} 0.08{{\\ \\rm per\\ cent}}$ (at 1σ level) on scales 10−4 & k & 101 h Mpc−1. In this paper, we demonstrate matryoshka by training the non-linear boost component emulator with analytic training data calculated with Halofit, which has been designed to replicate training data that would be generated using numerical simulations. Combining all the component emulator predictions we achieve an accuracy of ${\\lt} 0.75{{\\ \\rm per\\ cent}}$ (at 1σ level) when predicting the real space non-linear galaxy power spectrum on scales 0.0025 & k & 1 h Mpc−1. We use matryoshka to investigate the impact of the analysis set-up on cosmological constraints by conducting several full shape analyses of the real-space galaxy power spectrum. Specifically we investigate the impact of the minimum scale (or kmax), finding an improvement of ∼1.8× in the constraint on σ8 by pushing kmax from 0.25 to 0.85 h Mpc−1, highlighting the potential gains when using clustering emulators such as matryoshka in cosmological analyses.
Publisher: Oxford University Press (OUP)
Date: 02-11-2015
Publisher: Oxford University Press (OUP)
Date: 04-07-2013
DOI: 10.1093/MNRAS/STT988
Publisher: Oxford University Press (OUP)
Date: 30-11-2018
Publisher: Oxford University Press (OUP)
Date: 03-12-2015
Publisher: Oxford University Press (OUP)
Date: 07-02-2014
DOI: 10.1093/MNRAS/STU112
Publisher: Oxford University Press (OUP)
Date: 16-07-2021
Abstract: Baryon Acoustic Oscillations (BAO) are considered to be a very robust standard ruler against various systematics. This premise has been tested against observational systematics, but not to the level required for the next generation of galaxy surveys such as the Dark Energy Spectroscopic Instrument (DESI) and Euclid. In this paper, we investigate the effect of observational systematics on the BAO measurement of the final s le of quasars from the extended Baryon Oscillation Spectroscopic Survey Data Release 16 in order to prepare and hone a similar analysis for upcoming surveys. We employ catalogues with various treatments of imaging systematic effects using linear and neural network-based non-linear approaches and consider how the BAO measurement changes. We also test how the variations to the BAO fitting model respond to the observational systematics. As expected, we confirm that the BAO measurements obtained from the DR16 quasar s le are robust against imaging systematics well within the statistical error, while reporting slightly modified constraints that shift the line-of-sight BAO signal by less than 1.1 per cent. We use realistic simulations with similar redshift and angular distributions as the DR16 s le to conduct statistical tests for validating the pipeline, quantifying the significance of differences, and estimating the expected bias on the BAO scale in future high-precision data sets. Although we find a marginal impact for the eBOSS QSO data, the work presented here is of vital importance for constraining the nature of dark energy with the BAO feature in the new era of big data cosmology.
Publisher: Oxford University Press (OUP)
Date: 14-01-2016
Publisher: IOP Publishing
Date: 03-09-2019
Publisher: Oxford University Press (OUP)
Date: 05-04-2023
Abstract: The dependence of galaxy clustering on local density provides an effective method for extracting non-Gaussian information from galaxy surveys. The two-point correlation function (2PCF) provides a complete statistical description of a Gaussian density field. However, the late-time density field becomes non-Gaussian due to non-linear gravitational evolution and higher-order summary statistics are required to capture all of its cosmological information. Using a Fisher formalism based on halo catalogues from the Quijote simulations, we explore the possibility of retrieving this information using the density-split clustering (DS) method, which combines clustering statistics from regions of different environmental density. We show that DS provides more precise constraints on the parameters of the νΛCDM model compared to the 2PCF, and we provide suggestions for where the extra information may come from. DS improves the constraints on the sum of neutrino masses by a factor of 7 and by factors of 4, 3, 3, 6, and 5 for Ωm, Ωb, h, ns, and σ8, respectively. We compare DS statistics when the local density environment is estimated from the real or redshift-space positions of haloes. The inclusion of DS autocorrelation functions, in addition to the cross-correlation functions between DS environments and haloes, recovers most of the information that is lost when using the redshift-space halo positions to estimate the environment. We discuss the possibility of constructing simulation-based methods to model DS clustering statistics in different scenarios.
Publisher: American Physical Society (APS)
Date: 02-06-2020
Publisher: Springer Science and Business Media LLC
Date: 20-04-2010
Publisher: Oxford University Press (OUP)
Date: 04-02-2016
DOI: 10.1093/MNRAS/STW066
Publisher: Oxford University Press (OUP)
Date: 04-10-2011
Publisher: Oxford University Press (OUP)
Date: 28-06-2023
Abstract: We present, for the first time, an observational test of the consistency relation for the large-scale structure (LSS) of the Universe through a joint analysis of the anisotropic two- and three-point correlation functions (2PCF and 3PCF) of galaxies. We parameterize the breakdown of the LSS consistency relation in the squeezed limit by Es, which represents the ratio of the coefficients of the shift terms in the second-order density and velocity fluctuations. Es ≠ 1 is a sufficient condition under which the LSS consistency relation is violated. A novel aspect of this work is that we constrain Es by obtaining information about the non-linear velocity field from the quadrupole component of the 3PCF without taking the squeezed limit. Using the galaxy catalogues in the Baryon Oscillation Spectroscopic Survey (BOSS) Data Release 12, we obtain $E_{\\rm s} = -0.92_{-3.26}^{+3.13}$, indicating that there is no violation of the LSS consistency relation in our analysis within the statistical errors. Our parameterization is general enough that our constraint can be applied to a wide range of theories, such as multicomponent fluids, modified gravity theories, and their associated galaxy bias effects. Our analysis opens a new observational window to test the fundamental physics using the anisotropic higher-order correlation functions of galaxy clustering.
Publisher: Oxford University Press (OUP)
Date: 28-03-2017
DOI: 10.1093/MNRAS/STX751
Publisher: IOP Publishing
Date: 13-05-2009
Publisher: WORLD SCIENTIFIC
Date: 29-01-2015
Publisher: Oxford University Press (OUP)
Date: 28-09-2016
Publisher: IOP Publishing
Date: 05-2014
DOI: 10.1088/1475-7516/2014/05/027
Abstract: We measure the large-scale cross-correlation of quasars with the Lyα forest absorption, using over 164,000 quasars from Data Release 11 of the SDSS-III Baryon Oscillation Spectroscopic Survey. We extend the previous study of roughly 60,000 quasars from Data Release 9 to larger separations, allowing a measurement of the Baryonic Acoustic Oscillation (BAO) scale along the line of sight c /( H ( z = 2.36) r s ) = 9.0±0.3 and across the line of sight D A ( z = 2.36)/ r s = 10.8±0.4, consistent with CMB and other BAO data. Using the best fit value of the sound horizon from Planck data ( r s = 147.49 Mpc), we can translate these results to a measurement of the Hubble parameter of H ( z = 2.36) = 226±8 km s −1 Mpc −1 and of the angular diameter distance of D A ( z = 2.36) = 1590±60 Mpc. The measured cross-correlation function and an update of the code to fit the BAO scale (baofit) are made publicly available.
Publisher: Oxford University Press (OUP)
Date: 06-2012
Publisher: Elsevier BV
Date: 07-2009
Publisher: Oxford University Press (OUP)
Date: 23-08-2013
Publisher: IOP Publishing
Date: 05-05-2020
Publisher: Oxford University Press (OUP)
Date: 17-11-2015
Publisher: Oxford University Press (OUP)
Date: 16-05-2017
Publisher: Oxford University Press (OUP)
Date: 04-09-2018
Publisher: Oxford University Press (OUP)
Date: 26-10-2018
Publisher: Oxford University Press (OUP)
Date: 23-07-2201
Publisher: Oxford University Press (OUP)
Date: 19-02-2020
Abstract: Accurate modelling of non-linear scales in galaxy clustering will be crucial for data analysis of Stage IV galaxy surveys. A selection of competing non-linear models must be made based on validation studies. We provide a comprehensive set of forecasts of two different models for the halo redshift space power spectrum, namely the commonly applied TNS model and an effective field theory of large-scale structure (EFTofLSS) inspired model. Using simulation data and a least-χ2 analysis, we determine ranges of validity for the models. We then conduct an exploratory Fisher analysis using the full anisotropic power spectrum to investigate parameter degeneracies. We proceed to perform an MCMC analysis utilizing the monopole, quadrupole, and hexadecapole spectra, with a restricted range of scales for the latter in order to avoid biasing our growth rate, f, constraint. We find that the TNS model with a Lorentzian d ing and standard Eulerian perturbative modelling outperforms other variants of the TNS model. Our MCMC analysis finds that the EFTofLSS-based model may provide tighter marginalized constraints on f at z = 0.5 and z = 1 than the TNS model, despite having additional nuisance parameters. However this depends on the range of scales used as well as the fiducial values and priors on the EFT nuisance parameters. Finally, we extend previous work to provide a consistent comparison between the Fisher matrix and MCMC forecasts using the multipole expansion formalism, and find good agreement between them.
Publisher: Oxford University Press (OUP)
Date: 24-04-2013
DOI: 10.1093/MNRAS/STT514
Publisher: Oxford University Press (OUP)
Date: 19-11-2013
Publisher: Oxford University Press (OUP)
Date: 03-06-2013
DOI: 10.1093/MNRAS/STT799
Publisher: Oxford University Press (OUP)
Date: 04-01-2017
Publisher: Oxford University Press (OUP)
Date: 15-03-2017
DOI: 10.1093/MNRAS/STX633
Publisher: Oxford University Press (OUP)
Date: 16-09-2016
Publisher: Oxford University Press (OUP)
Date: 21-07-2014
Location: United Kingdom of Great Britain and Northern Ireland
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