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Related papers: Revisiting the Constraint on the Helium Abundance …

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We consider for the first time the ability of present-day cosmic microwave background (CMB) anisotropies data to determine the primordial helium mass fraction, Y_p. We find that CMB data alone gives the confidence interval 0.160 < Y_p <…

Astrophysics · Physics 2007-07-23 Roberto Trotta , Steen H. Hansen

Data from future high-precision Cosmic Microwave Background (CMB) measurements will be sensitive to the primordial Helium abundance $Y_p$. At the same time, this parameter can be predicted from Big Bang Nucleosynthesis (BBN) as a function…

Astrophysics · Physics 2009-03-24 Jan Hamann , Julien Lesgourgues , Gianpiero Mangano

We studied a constraint on the primordial helium abundance Y_p from current and future observations of CMB. Using the currently available data from WMAP, ACBAR, CBI and BOOMERANG, we obtained the constraint as Y_p = 0.25^{+0.10}_{-0.07} at…

Astrophysics · Physics 2008-11-26 Kazuhide Ichikawa , Toyokazu Sekiguchi , Tomo Takahashi

We present constraints on the number of relativistic species from a joint analysis of cosmic microwave background (CMB) fluctuations and light element abundances (helium and deuterium) compared to big bang nucleosynthesis (BBN) predictions.…

Cosmology and Nongalactic Astrophysics · Physics 2011-12-13 Kenneth M. Nollett , Gilbert P. Holder

We present the results of a joint investigation aimed at constraining the primordial He content ($Y_P$) on the basis of both the Cosmic Microwave Background (CMB) anisotropy and two stellar observables, namely the tip of the Red Giant…

Astrophysics · Physics 2009-11-07 G. Bono , A. Balbi , S. Cassisi , N. Vittorio , R. Buonanno

The products of primordial nucleosynthesis and the cosmic microwave background (CMB) photons are relics from the early evolution of the Universe whose observations probe the standard model of cosmology and provide windows on new physics…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Gary Steigman

We discuss what can be learned about the baryon density from an all-sky map of the cosmic microwave background (CMB) with sub-degree angular resolution. With only minimal assumptions about the primordial spectrum of density perturbations…

Astrophysics · Physics 2007-05-23 Marc Kamionkowski , Gerard Jungman , Arthur Kosowsky , David N. Spergel

Recent cosmic microwave background (CMB) results from BOOMERANG, MAXIMA, and DASI provide cosmological constraints on new physics that can be competitive with those derived from Big Bang Nucleosynthesis (BBN). In particular, both CMB and…

Astrophysics · Physics 2008-11-26 James P. Kneller , Robert J. Scherrer , Gary Steigman , Terry P. Walker

We present the results of analysis of constraints on cosmological parameters from cosmic microwave background (CMB) alone and in combination with galaxy cluster baryon fraction assuming inflation--generated adiabatic scalar fluctuations.…

Astrophysics · Physics 2009-11-06 M. Douspis , A. Blanchard , R. Sadat , J. G. Bartlett , M. Le Dour

We present cosmological constraints on deviations of Newton's constant at large scales, analyzing latest cosmic microwave background (CMB) anisotropies and primordial abundances of light elements synthesized by big bang nucleosynthesis…

Astrophysics · Physics 2009-11-10 K. Umezu , K. Ichiki , M. Yahiro

Cosmic microwave background (CMB) determinations of the baryon-to-photon ratio $\eta \propto \Omega_{\rm baryon} h^2$ will remove the last free parameter from (standard) big bang nucleosynthesis (BBN) calculations. This will make BBN a much…

Astrophysics · Physics 2008-11-26 Richard H. Cyburt , Brian D. Fields , Keith A. Olive

Big bang nucleosynthesis (BBN) and the cosmic microwave background (CMB) anisotropies independently predict the universal baryon density. Comparing their predictions will provide a fundamental test on cosmology. Using BBN and the CMB…

Astrophysics · Physics 2009-11-07 Richard H. Cyburt

Big bang nucleosynthesis (BBN) and the cosmic microwave background (CMB) have a long history together in the standard cosmology. The general concordance between the predicted and observed light element abundances provides a direct probe of…

Astrophysics · Physics 2009-11-10 Richard H. Cyburt

By using most of the present CMB and LSS measurements and the BBN constraints on the primordial helium abundance, Y_p, we set bounds on the radiation content of the Universe and neutrino properties. We consider lepton asymmetric…

Astrophysics · Physics 2010-02-26 Lucia Aurelia Popa , Ana Vasile

Big bang nucleosynthesis (BBN) and the cosmic microwave background (CMB) are two major pillars of cosmology. Standard BBN accurately predicts the primordial light element abundances ($^4$He, D, $^3$He and $^7$Li), depending on one…

Astrophysics · Physics 2009-11-10 Greg Huey , Richard H. Cyburt , Benjamin D. Wandelt

We derive constraints on the time variation of the Higgs vacuum expectation value $<\phi>$ through the effects on Big Bang nucleosynthesis (BBN) and the cosmic microwave background (CMB). In the former case, we include the…

Astrophysics · Physics 2009-11-07 Jerry Jaiyul Yoo , Robert J. Scherrer

We compute the joint constraints on ten cosmological parameters from the latest CMB measurements. The lack of a significant second acoustic peak in the latest Boomerang and Maxima data favors models with more baryons than Big Bang…

Astrophysics · Physics 2009-10-07 Max Tegmark , Matias Zaldarriaga

Primordial or Big Bang nucleosynthesis (BBN) is one of the three historical strong evidences for the Big-Bang model together with the expansion of the Universe and the Cosmic Microwave Background radiation (CMB). The recent results by the…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-29 Alain Coc , Jean-Philippe Uzan , Elisabeth Vangioni

We present calculations showing that upcoming Cosmic Microwave Background (CMB) experiments will have the power to improve on current constraints on neutrino masses and provide new limits on neutrino degeneracy parameters. The latter could…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 M. Shimon , N. J. Miller , C. T. Kishimoto , C. J. Smith , G. M. Fuller , B. G. Keating

The cosmic microwave background (CMB) places a variety of model-independent constraints on the strength interactions of the dominant component of dark matter with the Standard Model. Percent-level subcomponents of the dark matter can evade…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-06 Roland de Putter , Olivier Doré , Jérôme Gleyzes , Daniel Green , Joel Meyers
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