A big bang nucleosynthesis likelihood analysis of the baryon-to-photon ratio and the number of light particle degrees of freedom

Keith A. Olive; David Thomas

doi:10.1016/S0927-6505(97)00008-X

A big bang nucleosynthesis likelihood analysis of the baryon-to-photon ratio and the number of light particle degrees of freedom

Keith A. Olive, David Thomas

Research output: Contribution to journal › Article › peer-review

25 Scopus citations

Abstract

We extend the model-independent likelihood analysis of big bang nucleosynthesis (BBN) based on ⁴He and ⁷Li to allow for numbers of degrees of freedom which differ from the standard model value characterized by N_v = 3. We use the two-dimensional likelihood functions to simultaneously constrain the baryon-to-photon ratio and the number of light neutrinos. The upper limit thus obtained is N_v < 4.0 (at 95% C.L.). We also consider the consequences if recent observations of deuterium in high-redshift QSO absorption-line systems (QSOALS) are confirmed.

Original language	English (US)
Pages (from-to)	27-34
Number of pages	8
Journal	Astroparticle Physics
Volume	7
Issue number	1-2
DOIs	https://doi.org/10.1016/S0927-6505(97)00008-X
State	Published - Jun 1997

Bibliographical note

Funding Information:
We thankC . Copi, B. Fields,K . Kainulainena, nd T. Walker for usefulc onversationsT.h is work was supported in part by DOE grant DE-FG02-94ER40823a t Minnesota,a nd by NASA grant NAG5-2835a t Florida.

Publisher link

10.1016/S0927-6505(97)00008-X

Find It

Find It at U of M Libraries

Cite this

@article{824bb8965879451ca5438b5e48fd1a08,

title = "A big bang nucleosynthesis likelihood analysis of the baryon-to-photon ratio and the number of light particle degrees of freedom",

abstract = "We extend the model-independent likelihood analysis of big bang nucleosynthesis (BBN) based on 4He and 7Li to allow for numbers of degrees of freedom which differ from the standard model value characterized by Nv = 3. We use the two-dimensional likelihood functions to simultaneously constrain the baryon-to-photon ratio and the number of light neutrinos. The upper limit thus obtained is Nv < 4.0 (at 95% C.L.). We also consider the consequences if recent observations of deuterium in high-redshift QSO absorption-line systems (QSOALS) are confirmed.",

author = "Olive, {Keith A.} and David Thomas",

note = "Funding Information: We thankC . Copi, B. Fields,K . Kainulainena, nd T. Walker for usefulc onversationsT.h is work was supported in part by DOE grant DE-FG02-94ER40823a t Minnesota,a nd by NASA grant NAG5-2835a t Florida.",

year = "1997",

month = jun,

doi = "10.1016/S0927-6505(97)00008-X",

language = "English (US)",

volume = "7",

pages = "27--34",

journal = "Astroparticle Physics",

issn = "0927-6505",

publisher = "Elsevier",

number = "1-2",

}

TY - JOUR

T1 - A big bang nucleosynthesis likelihood analysis of the baryon-to-photon ratio and the number of light particle degrees of freedom

AU - Olive, Keith A.

AU - Thomas, David

N1 - Funding Information: We thankC . Copi, B. Fields,K . Kainulainena, nd T. Walker for usefulc onversationsT.h is work was supported in part by DOE grant DE-FG02-94ER40823a t Minnesota,a nd by NASA grant NAG5-2835a t Florida.

PY - 1997/6

Y1 - 1997/6

N2 - We extend the model-independent likelihood analysis of big bang nucleosynthesis (BBN) based on 4He and 7Li to allow for numbers of degrees of freedom which differ from the standard model value characterized by Nv = 3. We use the two-dimensional likelihood functions to simultaneously constrain the baryon-to-photon ratio and the number of light neutrinos. The upper limit thus obtained is Nv < 4.0 (at 95% C.L.). We also consider the consequences if recent observations of deuterium in high-redshift QSO absorption-line systems (QSOALS) are confirmed.

AB - We extend the model-independent likelihood analysis of big bang nucleosynthesis (BBN) based on 4He and 7Li to allow for numbers of degrees of freedom which differ from the standard model value characterized by Nv = 3. We use the two-dimensional likelihood functions to simultaneously constrain the baryon-to-photon ratio and the number of light neutrinos. The upper limit thus obtained is Nv < 4.0 (at 95% C.L.). We also consider the consequences if recent observations of deuterium in high-redshift QSO absorption-line systems (QSOALS) are confirmed.

UR - http://www.scopus.com/inward/record.url?scp=0031161458&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0031161458&partnerID=8YFLogxK

U2 - 10.1016/S0927-6505(97)00008-X

DO - 10.1016/S0927-6505(97)00008-X

M3 - Article

AN - SCOPUS:0031161458

VL - 7

SP - 27

EP - 34

JO - Astroparticle Physics

JF - Astroparticle Physics

SN - 0927-6505

IS - 1-2

ER -

A big bang nucleosynthesis likelihood analysis of the baryon-to-photon ratio and the number of light particle degrees of freedom

Abstract

Bibliographical note

Publisher link

Find It

Other files and links

Fingerprint

Cite this