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Over the next decade, improvements in cosmological parameter constraints will be driven by surveys of large-scale structure. Its inherent non-linearity suggests that significant information will be embedded in higher correlations beyond the…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-19 Joyce Byun , Alexander Eggemeier , Donough Regan , David Seery , Robert E. Smith

We develop a semi-analytic method for assessing the impact of the large-scale IGM temperature fluctuations expected following He${\rm\,{\scriptstyle II}}$ reionization on three-dimensional clustering measurements of the Ly$\alpha$ forest.…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Bradley Greig , James S. Bolton , J. Stuart B. Wyithe

Anomaly detectors are often used to produce a ranked list of statistical anomalies, which are examined by human analysts in order to extract the actual anomalies of interest. Unfortunately, in realworld applications, this process can be…

Machine Learning · Computer Science 2017-09-01 Shubhomoy Das , Weng-Keen Wong , Alan Fern , Thomas G. Dietterich , Md Amran Siddiqui

A key challenge in estimating causal effects from observational data is handling confounding and is commonly achieved through weighting methods that balance distribution of covariates between treatment and control groups. Weighting…

Methodology · Statistics 2025-12-23 Simion De , Jared D. Huling

We used the mark weighted correlation functions (MCFs), $W(s)$, to study the large scale structure of the Universe. We studied five types of MCFs with the weighting scheme $\rho^\alpha$, where $\rho$ is the local density, and $\alpha$ is…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-02 Yizhao Yang , Haitao Miao , Qinglin Ma , Miaoxin Liu , Cristiano G. Sabiu , Jaime Forero-Romero , Yuanzhu Huang , Limin Lai , Qiyue Qian , Yi Zheng , Xiao-Dong Li

We explore possibility of using the three dimensional bispectra of the Ly-alpha forest and the redshifted 21-cm signal from the post-reionization epoch to constrain primordial non-Gaussianity. Both these fields map out the large scale…

Cosmology and Nongalactic Astrophysics · Physics 2013-04-04 Tapomoy Guha Sarkar , Dhiraj Kumar Hazra

We present a method for fast evaluation of the covariance matrix for a two-point galaxy correlation function (2PCF) measured with the Landy-Szalay estimator. The standard way of evaluating the covariance matrix consists in running the…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-26 E. Keihanen , V. Lindholm , P. Monaco , L. Blot , C. Carbone , K. Kiiveri , A. G. Sánchez , A. Viitanen , J. Valiviita , A. Amara , N. Auricchio , M. Baldi , D. Bonino , E. Branchini , M. Brescia , J. Brinchmann , S. Camera , V. Capobianco , J. Carretero , M. Castellano , S. Cavuoti , A. Cimatti , R. Cledassou , G. Congedo , L. Conversi , Y. Copin , L. Corcione , M. Cropper , A. Da Silva , H. Degaudenzi , M. Douspis , F. Dubath , C. A. J. Duncan , X. Dupac , S. Dusini , A. Ealet , S. Farrens , S. Ferriol , M. Frailis , E. Franceschi , M. Fumana , B. Gillis , C. Giocoli , A. Grazian , F. Grupp , L. Guzzo , S. V. H. Haugan , H. Hoekstra , W. Holmes , F. Hormuth , K. Jahnke , M. Kümmel , S. Kermiche , A. Kiessling , T. Kitching , M. Kunz , H. Kurki-Suonio , S. Ligori , P. B. Lilje , I. Lloro , E. Maiorano , O. Mansutti , O. Marggraf , F. Marulli , R. Massey , M. Melchior , M. Meneghetti , G. Meylan , M. Moresco , B. Morin , L. Moscardini , E. Munari , S. M. Niemi , C. Padilla , S. Paltani , F. Pasian , K. Pedersen , V. Pettorino , S. Pires , G. Polenta , M. Poncet , L. Popa , F. Raison , A. Renzi , J. Rhodes , E. Romelli , R. Saglia , B. Sartoris , P. Schneider , T. Schrabback , A. Secroun , G. Seidel , C. Sirignano , G. Sirri , L. Stanco , C. Surace , P. Tallada-Crespí , D. Tavagnacco , A. N. Taylor , I. Tereno , R. Toledo-Moreo , F. Torradeflot , E. A. Valentijn , L. Valenziano , T. Vassallo , Y. Wang , J. Weller , G. Zamorani , J. Zoubian , S. Andreon , D. Maino , S. de la Torre

In the WMAP era of high precision cosmology an accurate determination of the matter power spectrum from lyman-alpha forest data becomes crucial. When combining the matter power spectrum derived from CMB experiments with that inferred from…

Astrophysics · Physics 2007-05-23 Matteo Viel

A combined analysis of Cosmic Microwave Background (CMB) and Lyman-a forest data allows to constrain the matter power spectrum from small scales of about 1 Mpc/h all the way to the horizon scale. The long lever arm and complementarity…

Astrophysics · Physics 2009-10-08 Matteo Viel , Martin G. Haehnelt , Antony Lewis

Large scale structure surveys are likely the next leading probe of cosmological information. It is therefore crucial to reliably predict their observables. The Effective Field Theory of Large Scale Structures (EFTofLSS) provides a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 John Joseph M. Carrasco , Simon Foreman , Daniel Green , Leonardo Senatore

Using the Ly$\alpha$ mass assignment scheme (LyMAS), we make theoretical predictions for the 3-dimensional 3-point correlation function (3PCF) of the Ly$\alpha$ forest at redshift $z=2.3$. We bootstrap results from the (100 $h^{-1} \mbox{…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-06 Suk Sien Tie , David H. Weinberg , Paul Martini , Wei Zhu , Sebastien Peirani , Teresita Suarez , Stephane Colombi

We derive an analytical expression for a novel large-scale structure observable: the line correlation function. The line correlation function, which is constructed from the three-point correlation function of the phase of the density field,…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-09 Richard Wolstenhulme , Camille Bonvin , Danail Obreschkow

Spectroscopy with HST/STIS Echelle and VLT/UVES of the bright QSO HE 0515-4414 (z_em =1.73, B = 15.0) offers for the first time the opportunity to study the Lyman alpha forest in the redshift range 0.9 < z < 1.7 at a resolution ~ 10 km/s.…

Astrophysics · Physics 2009-11-07 Eckart Janknecht , Robert Baade , Dieter Reimers

We present a study of the spatial coherence of the intergalactic medium toward two pairs of high-redshift quasars with moderate angular separations observed with Keck/ESI, Q1422+2309A/Q1424+2255 (z_em = 3.63, theta = 39") and Q1439-0034A/B…

Astrophysics · Physics 2009-11-10 George D. Becker , Wallace L. W. Sargent , Michael Rauch

Absorption between the rest-frame wavelengths of 973 and 1026 Angstroms in quasar spectra arises from two sources (apart from occasional metals): one is due to Lyman-alpha (Lya) absorption by materials at a low redshift, and the other from…

Astrophysics · Physics 2009-11-07 Mark Dijkstra , Adam Lidz , Lam Hui

Fused Lasso was proposed to characterize the sparsity of the coefficients and the sparsity of their successive differences for the linear regression. Due to its wide applications, there are many existing algorithms to solve fused Lasso.…

Computation · Statistics 2024-04-17 Pan Shang , Huangyue Chen , Lingchen Kong

With recent developments in remote sensing technologies, plot-level forest resources can be predicted utilizing airborne laser scanning (ALS). The prediction is often assisted by mostly vertical summaries of the ALS point clouds. We present…

Applications · Statistics 2021-05-03 Henrike Häbel , András Balázs , Mari Myllymäki

Field-level inference is emerging as a promising technique for optimally extracting information from cosmological datasets. Indeed, previous analyses have shown field-based inference produces tighter parameter constraints than power…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-04 Supranta S. Boruah , Eduardo Rozo

We present the first detection of a correlation between the Lyman-$\alpha$ forest and cosmic microwave background (CMB) lensing. For each Lyman-$\alpha$ forest in SDSS-III/BOSS DR12, we correlate the one-dimensional power spectrum with the…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-15 Cyrille Doux , Emmanuel Schaan , Eric Aubourg , Ken Ganga , Khee-Gan Lee , David N. Spergel , Julien Tréguer

An analytical framework is presented to understand the effects of a fluctuating intensity of the cosmic ionising background on the correlations of the Ly{\alpha} forest transmission fraction measured in quasar spectra. In the absence of…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-24 Satya Gontcho A Gontcho , Jordi Miralda-Escudé , Nicolás G. Busca