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Related papers: Nonparametric 3D map of the IGM using the Lyman-al…

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The Lyman-alpha forest has opened a new redshift regime for cosmological investigation. At z > 2 it provides a unique probe of cosmic geometry and an independent constraint on dark energy that is not subject to standard candle or ruler…

Astrophysics · Physics 2009-11-13 Andrew R. Marble , Kristoffer A. Eriksen , Chris D. Impey , Lei Bai , Lance Miller

We present an improved analytical model to predict the Lyman-alpha forest at the field level in redshift space from the dark matter field, expanding upon the widely-used Fluctuating Gunn-Peterson approximation (FGPA). In particular, we…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-25 Francesco Sinigaglia , Francisco-Shu Kitaura , Kentaro Nagamine , Yuri Oku , Andrés Balaguera-Antolínez

We analyze the flux power spectrum and its covariance using simulated Lyman alpha forests. We find that pseudo-hydro techniques are good approximations of hydrodynamical simulations at high redshift. However, the pseudo-hydro techniques…

Astrophysics · Physics 2009-11-11 Hu Zhan , Romeel Dave , Daniel Eisenstein , Neal Katz

The Lyman-$\beta$ forest refers to a region in the spectra of distant quasars that lies between the rest-frame Lyman-$\beta$ and Lyman-$\gamma$ emissions. The forest in this region is dominated by a combination of absorption due to resonant…

We extend our super-resolution and emulation framework for cosmological dark matter simulations to include hydrodynamics. We present a two-stage deep learning model to emulate high-resolution (HR-HydroSim) baryonic fields from…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-23 Fatemeh Hafezianzadeh , Xiaowen Zhang , Yueying Ni , Rupert A. C. Croft , Tiziana DiMatteo , Mahdi Qezlou , Simeon Bird

Initial density distribution provides a basis for understanding the complete evolution of cosmological density fluctuations. While reconstruction in our local Universe exploits the observations of galaxy surveys with large volumes,…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-28 Meng Zhou , Yi Mao

We present a suite of cosmological N-body simulations with cold dark matter and baryons aiming at modeling the low-density regions of the IGM as probed by the Lyman-$\alpha$ forests at high redshift. The simulations are designed to match…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 A. Borde , N. Palanque-Delabrouille , G. Rossi , M. Viel , J. Bolton , Ch. Yèche , J. -M. LeGoff , J. Rich

Reconstructing object geometry from radio frequency (RF) signals is fundamentally challenging due to the lensless imaging nature of RF sensing, which leads to low spatial resolution and high noise. Unlike light signals, RF signals can…

Computer Vision and Pattern Recognition · Computer Science 2026-05-29 Jiachen Lu , Hailan Shanbhag , Haitham Al Hassanieh

Full-physics cosmological simulations are powerful tools for studying the formation and evolution of structure in the universe but require extreme computational resources. Here, we train a convolutional neural network to use a cheaper…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-04 Peter Harrington , Mustafa Mustafa , Max Dornfest , Benjamin Horowitz , Zarija Lukić

The linear algorithm of the the full non-linear large scale structure of Gaussian random fields is extended here to to perform non-linear CRs. The procedure consists of: (1) Using linear CR of low resolution data to construct a high…

Astrophysics · Physics 2016-08-30 V. Bistolas , Y. Hoffman

We present a quantitative model of Lyman-alpha (Ly-alpha) emission throughout cosmic history and determine the prospects for intensity mapping of spatial fluctuations in the Ly-alpha signal. Since i) our model assumes at z>6 the minimum…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Anthony Pullen , Olivier Dore , Jamie Bock

We present DeepCHART (Deep learning for Cosmological Heterogeneity and Astrophysical Reconstruction via Tomography), a deep learning framework designed to reconstruct the three-dimensional dark matter density field at redshift $z=2.5$ from…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-02 Soumak Maitra , Matteo Viel , Girish Kulkarni

Weak lensing mass-mapping is a useful tool to access the full distribution of dark matter on the sky, but because of intrinsic galaxy ellipticies and finite fields/missing data, the recovery of dark matter maps constitutes a challenging…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-05 Benjamin Remy , Francois Lanusse , Niall Jeffrey , Jia Liu , Jean-Luc Starck , Ken Osato , Tim Schrabback

The Lyman-$\alpha$ forests observed in the spectra of high-redshift quasars can be used as a tracer of the cosmological matter density to study baryon acoustic oscillations (BAO) and the Alcock-Paczynski effect. Extraction of cosmological…

Arguably the best hope of understanding the tail end of the reionization of the intergalactic medium (IGM) at redshift z > 6 is through the detection and characterization of the Gunn-Peterson (GP) damping wing absorption of the IGM in…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-25 Roban Hultman Kramer , Zoltan Haiman

Accurate quantification of forest coverage and combustible biomass (fuel load) is critical for wildfire risk assessment and ecosystem management. However, traditional methods relying on airborne LiDAR or field surveys are cost-prohibitive…

Computer Vision and Pattern Recognition · Computer Science 2026-05-12 Quanyun Wu , Kyle Gao , Wentao Sun , Zhengsen Xu , Hudson Sun , Linlin Xu , Yuhao Chen , David A. Clausi , Jonathan Li

The Lyman-alpha forest is the large-scale structure probe for which we appear to have modeling control to the highest wavenumbers. This makes the Lyman-alpha forest of great interest for constraining the warmness/fuzziness of dark matter…

Cosmology and Nongalactic Astrophysics · Physics 2021-10-27 Bayu Wilson , Vid Iršič , Matthew McQuinn

Observations of the Lyman-$\alpha$ (Ly$\alpha$) forest in spectra of distant quasars enable us to probe the matter power spectrum at relatively small scales. With several upcoming surveys, it is expected that there will be a many-fold…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-15 Bhaskar Arya , Tirthankar Roy Choudhury , Aseem Paranjape , Prakash Gaikwad

We present the Lyman-$\alpha$ flux power spectrum measurements of the XQ-100 sample of quasar spectra obtained in the context of the European Southern Observatory Large Programme "Quasars and their absorption lines: a legacy survey of the…

The high redshift galaxy MS1512-cB58 (z=2.724, m_V=20.64) has been observed with the very efficient high resolution echelle spectrograph VLT/UVES. Although this is a very challenging observational program for a Southern hemisphere telescope…

Astrophysics · Physics 2009-11-07 S. Savaglio , N. Panagia , P. Padovani
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