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Since the discovery of the accelerated cosmic expansion, one of the most important tasks in observational cosmology is to determine the nature of the dark energy. We should build our understanding on a minimum of assumptions in order to…

Cosmology and Nongalactic Astrophysics · Physics 2019-12-11 Sophia Haude , Shabnam Salehi , Sofía Vidal , Matteo Maturi , Matthias Bartelmann

I discuss the use of Type Ia supernovae (SNe Ia) for cosmological distance determinations. Low-redshift SNe Ia (z < 0.1) demonstrate that the Hubble expansion is linear with H_0 = 72 +/- 8 km/s/Mpc, and that the properties of dust in other…

Astrophysics · Physics 2015-11-11 Alexei V. Filippenko

This review summarizes recent attempts to reconstruct the expansion history of the Universe and to probe the nature of dark energy. Reconstruction methods can be broadly classified into parametric and non-parametric approaches. It is…

Astrophysics · Physics 2008-11-26 Varun Sahni , Alexei Starobinsky

A statistical method for reconstructing large scale structure behind the Zone of Avoidance is presented. It also corrects for shot-noise and for redshift distortion in galaxy surveys. The galaxy distribution is expanded in an orthogonal set…

Astrophysics · Physics 2007-05-23 Ofer Lahav

We investigate the charm quark system using the relativistic heavy quark action on 2+1 flavor PACS-CS configurations previously generated on $32^3 \times 64$ lattice. The dynamical up-down and strange quark masses are set to the physical…

High Energy Physics - Lattice · Physics 2013-05-29 Y. Namekawa , S. Aoki , K. -I. Ishikawa , N. Ishizuka , T. Izubuchi , K. Kanaya , Y. Kuramashi , M. Okawa , Y. Taniguchi , A. Ukawa , N. Ukita , T. Yoshié

The cosmological principle assumes the isotropy of the Universe at large scales. It is a foundational assumption in the $\Lambda$CDM model, which is the current standard model of cosmology. Recent tensions give legitimacy to investigating…

Cosmic shear surveys serve as a powerful tool for mapping the underlying matter density field, including non-visible dark matter. A key challenge in cosmic shear surveys is the accurate reconstruction of lensing convergence ($\kappa$) maps…

Instrumentation and Methods for Astrophysics · Physics 2025-11-27 Yuan Shi , Pengjie Zhang , Furen Deng , Shuren Zhou , Hongbo Cai , Ji Yao , Zeyang Sun

We determine the MS-bar charm quark mass from a charmonium QCD sum rules analysis. On the theoretical side we use input from perturbation theory at O(alpha_s^3). Improvements with respect to previous O(alpha_s^3) analyses include (1) an…

High Energy Physics - Phenomenology · Physics 2013-07-30 Bahman Dehnadi , Andre H. Hoang , Vicent Mateu , S. Mohammad Zebarjad

We investigate the potential of using a sample of very high-redshift ($2\lesssim z \lesssim6$) (VHZ) Type Ia supernovae (SNe~Ia) attainable by the James Webb Space Telescope (JWST) on constraining cosmological parameters. At such high…

Cosmology and Nongalactic Astrophysics · Physics 2022-12-21 Jia Lu , Lifan Wang , Xingzhuo Chen , David Rubin , Saul Perlmutter , Dietrich Baade , Jeremy Mould , Jozsef Vinko , Eniko Regos , Anton M. Koekemoer

Combined HERA data on charm production in deep-inelastic scattering have previously been used to determine the charm-quark running mass $m_c(m_c)$ in the MSbar renormalisation scheme. Here, the same data are used as a function of the photon…

In this talk I explained briefly the advantages of using genetic algorithms on any measured data but specially astronomical ones. This kind of algorithms are not only a better computational paradigm, but they also allow for a more profound…

Data Analysis, Statistics and Probability · Physics 2015-05-20 O. López-Corona

We propose a new variable, the charm fraction, for collider searches for new physics. We analyze this variable in the context of searches for simplified supersymmetry models with squarks, the gluino, and the bino, assuming that only the…

High Energy Physics - Phenomenology · Physics 2017-10-25 Sho Iwamoto , Gabriel Lee , Yael Shadmi , Yaniv Weiss

We develop and apply a new framework for reconstructing the ionization history during the epoch of recombination with combinations of cosmic microwave background (CMB), baryon acoustic oscillation (BAO) and supernova data. We find a wide…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-15 Gabriel P. Lynch , Lloyd Knox , Jens Chluba

The Hubble expansion of the Universe is considered in the classical limit of a Big Bang quantum cosmology. In an IR-consistent coupling to the the bare cosmological constant, we infer a dark energy as a relic of the Big Bang by loss of…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-13 Maurice H. P. M. van Putten

Type Ia supernovae (SNae Ia), standardisable candles that allow tracing the expansion history of the Universe, are instrumental in constraining cosmological parameters, particularly dark energy. State-of-the-art likelihood-based analyses…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-14 Konstantin Karchev , Roberto Trotta , Christoph Weniger

The 21-cm power spectrum of reionization is a promising probe for cosmology and fundamental physics. Exploiting this new observable, however, requires fast predictors capable of efficiently scanning the very large parameter space of…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-15 Aurel Schneider , Timothée Schaeffer , Sambit K. Giri

In this paper, three kinds of simple parameterized deceleration parameters $q(z)=a+\frac{b z}{1+z}$, $q(z)=a+\frac{b z}{(1+z)^2}$ and $q(z)={1/2}+\frac{a z+b}{(1+z)^2}$ are reconstructed from the latest Sne Ia Gold dataset, observational…

Astrophysics · Physics 2009-11-13 Lixin Xu , Chengwu Zhang , Baorong Chang , Hongya Liu

We discuss the role of so-called "intrinsic-charm" operators in semi-leptonic B-meson decays, which appear first at order 1/m_b^3 in the heavy quark expansion. We show by explicit calculation that -- at scales mu <= m_c -- the contributions…

High Energy Physics - Phenomenology · Physics 2008-11-26 C. Breidenbach , T. Feldmann , T. Mannel , S. Turczyk

We propose two model independent methods to obtain constraints on the transition and equivalence redshifts $z_{tr}$, $z_{eq}$. In particular, we consider $z_{tr}$ as the onset of cosmic acceleration, whereas $z_{eq}$ the redshift at which…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-17 Salvatore Capozziello , Peter K. S. Dunsby , Orlando Luongo

We use updated Type Ia Pantheon+ supernova, baryon acoustic oscillation, and Hubble parameter (now also accounting for correlations) data, as well as new reverberation-measured C IV quasar data, and quasar angular size, H II starburst…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-19 Shulei Cao , Bharat Ratra