Search Results for author: Matias Zaldarriaga

Found 19 papers, 11 papers with code

A new approach to template banks of gravitational waves with higher harmonics: reducing matched-filtering cost by over an order of magnitude

1 code implementation23 Oct 2023 Digvijay Wadekar, Tejaswi Venumadhav, Ajit Kumar Mehta, Javier Roulet, Seth Olsen, Jonathan Mushkin, Barak Zackay, Matias Zaldarriaga

The templates used in current searches in the LIGO-Virgo-Kagra (LVK) data model the dominant quadrupole mode $(\ell, m)=(2, 2)$ of the signals, and omit sub-dominant higher-order modes (HM) such as $(\ell, m)=(3, 3)$, $(4, 4)$, which are predicted by general relativity.

Fewer Mocks and Less Noise: Reducing the Dimensionality of Cosmological Observables with Subspace Projections

no code implementations7 Sep 2020 Oliver H. E. Philcox, Mikhail M. Ivanov, Matias Zaldarriaga, Marko Simonovic, Marcel Schmittfull

The procedure is validated with full-shape analyses of power spectra from BOSS DR12 mock catalogs, showing that the 96-bin power spectra can be replaced by 12 subspace coefficients without biasing the output cosmology; this allows for accurate parameter inference using only $\sim 100$ mocks.

Cosmology and Nongalactic Astrophysics Instrumentation and Methods for Astrophysics High Energy Physics - Theory Data Analysis, Statistics and Probability

Blinded challenge for precision cosmology with large-scale structure: results from effective field theory for the redshift-space galaxy power spectrum

1 code implementation18 Mar 2020 Takahiro Nishimichi, Guido D'Amico, Mikhail M. Ivanov, Leonardo Senatore, Marko Simonović, Masahiro Takada, Matias Zaldarriaga, Pierre Zhang

An accurate theoretical template for the galaxy power spectrum is a key for the success of ongoing and future spectroscopic surveys.

Cosmology and Nongalactic Astrophysics

Combining Full-Shape and BAO Analyses of Galaxy Power Spectra: A 1.6% CMB-independent constraint on H0

no code implementations10 Feb 2020 Oliver H. E. Philcox, Mikhail M. Ivanov, Marko Simonović, Matias Zaldarriaga

We present cosmological constraints from a joint analysis of the pre- and post-reconstruction galaxy power spectrum multipoles from the final data release of the Baryon Oscillation Spectroscopic Survey (BOSS).

Cosmology and Nongalactic Astrophysics General Relativity and Quantum Cosmology High Energy Physics - Phenomenology

Cosmological Parameters and Neutrino Masses from the Final Planck and Full-Shape BOSS Data

no code implementations17 Dec 2019 Mikhail M. Ivanov, Marko Simonović, Matias Zaldarriaga

We present a joint analysis of the Planck cosmic microwave background (CMB) and Baryon Oscillation Spectroscopic Survey (BOSS) final data releases.

Cosmology and Nongalactic Astrophysics High Energy Physics - Phenomenology

Cosmological Parameters from the BOSS Galaxy Power Spectrum

no code implementations11 Sep 2019 Mikhail M. Ivanov, Marko Simonović, Matias Zaldarriaga

We present cosmological parameter measurements from the publicly available Baryon Oscillation Spectroscopic Survey (BOSS) data on anisotropic galaxy clustering in Fourier space.

Cosmology and Nongalactic Astrophysics General Relativity and Quantum Cosmology High Energy Physics - Phenomenology

New Binary Black Hole Mergers in the Second Observing Run of Advanced LIGO and Advanced Virgo

1 code implementation15 Apr 2019 Tejaswi Venumadhav, Barak Zackay, Javier Roulet, Liang Dai, Matias Zaldarriaga

The most secure new event, GW170121 ($p_{\rm astro} > 0. 99$), is also notable due to its inferred negative value of $\chi_{\rm eff}$, which is inconsistent with being positive at the $\approx 95. 8\%$ confidence level.

High Energy Astrophysical Phenomena Cosmology and Nongalactic Astrophysics Instrumentation and Methods for Astrophysics General Relativity and Quantum Cosmology

A Highly Spinning and Aligned Binary Black Hole Merger in the Advanced LIGO First Observing Run

1 code implementation27 Feb 2019 Barak Zackay, Tejaswi Venumadhav, Liang Dai, Javier Roulet, Matias Zaldarriaga

We report a new binary black hole merger in the publicly available LIGO First Observing Run (O1) data release.

High Energy Astrophysical Phenomena Instrumentation and Methods for Astrophysics General Relativity and Quantum Cosmology

Modeling Biased Tracers at the Field Level

2 code implementations26 Nov 2018 Marcel Schmittfull, Marko Simonović, Valentin Assassi, Matias Zaldarriaga

In contrast, for linear bias the mean-square model error can be higher than the Poisson prediction by factors of up to a few on large scales, and it becomes scale dependent already in the linear regime.

Cosmology and Nongalactic Astrophysics

Constraints on Binary Black Hole Populations from LIGO-Virgo Detections

1 code implementation27 Jun 2018 Javier Roulet, Matias Zaldarriaga

The three lightest binary black hole events are consistent with having a maximally spinning secondary but only for small mass ratios ($q\lesssim 0. 4$) as a result of the spin-mass ratio degeneracy.

High Energy Astrophysical Phenomena

Heating of the intergalactic medium by the cosmic microwave background during cosmic dawn

1 code implementation6 Apr 2018 Tejaswi Venumadhav, Liang Dai, Alexander Kaurov, Matias Zaldarriaga

We also find that the effect is more dramatic in non-standard scenarios that either enhance the radio background above the CMB or invoke new physics to cool the gas in order to explain the EDGES results.

Cosmology and Nongalactic Astrophysics

Efficient Evaluation of Cosmological Angular Statistics

2 code implementations14 May 2017 Valentin Assassi, Marko Simonović, Matias Zaldarriaga

In this paper, we provide a simple and fast method to compute the angular power spectrum and bispectrum of any observable.

Cosmology and Nongalactic Astrophysics

Iterative initial condition reconstruction

1 code implementation21 Apr 2017 Marcel Schmittfull, Tobias Baldauf, Matias Zaldarriaga

In our idealized dark matter simulations, the method improves the BAO signal-to-noise ratio by a factor of 2. 7 at $z=0$ and by a factor of 2. 5 at $z=0. 6$, improving standard BAO reconstruction by $70\%$ at $z=0$ and $30\%$ at $z=0. 6$, and matching the optimal BAO signal and signal-to-noise ratio of the linear density in the same volume.

Cosmology and Nongalactic Astrophysics

Solving Large Scale Structure in Ten Easy Steps with COLA

2 code implementations2 Jan 2013 Svetlin Tassev, Matias Zaldarriaga, Daniel Eisenstein

Achieving a similar level of accuracy in halo statistics without the COLA method requires at least 3 times more timesteps than when COLA is employed.

Cosmology and Nongalactic Astrophysics

Separating the Early Universe from the Late Universe: cosmological parameter estimation beyond the black box

1 code implementation2 Jul 2002 Max Tegmark, Matias Zaldarriaga

We present a method for measuring the cosmic matter budget without assumptions about speculative Early Universe physics, and for measuring the primordial power spectrum P*(k) non-parametrically, either by combining CMB and LSS information or by using CMB polarization.

Clustering

CMBFAST for spatially closed universes

no code implementations11 Nov 1999 Matias Zaldarriaga, Uros Seljak

We extend the cosmological linear perturbation theory code CMBFAST to closed geometries.

astro-ph

Gravitational Lensing Effect on Cosmic Microwave Background Polarization

no code implementations13 Mar 1998 Matias Zaldarriaga, Uros Seljak

As in the case of temperature spectrum gravitational lensing leads to smoothing of narrow features and enhancement of power on the damping tail of the power spectrum.

astro-ph

A Complete Treatment of CMB Anisotropies in a FRW Universe

no code implementations9 Sep 1997 Wayne Hu, Uros Seljak, Martin White, Matias Zaldarriaga

We generalize the total angular momentum method for computing Cosmic Microwave Background anisotropies to Friedman-Robertson-Walker (FRW) spaces with arbitrary geometries.

astro-ph

A Line of Sight Approach to Cosmic Microwave Background Anisotropies

no code implementations8 Mar 1996 Uros Seljak, Matias Zaldarriaga

The source term can be expressed in terms of photon, baryon and metric perturbations, all of which can be calculated using a small number of differential equations.

astro-ph

Cannot find the paper you are looking for? You can Submit a new open access paper.