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(Primordial Nucleosynthesis*)
B. Kämpfer
Research Center Rossendorf/Dresden & Technical University Dresden
- Expanding Universe- Prior to Nucleosynthesis- First Three Minutes: Creating Light Nuclei
* Based on Ms. of W. Wustmann, July 22, 2005
BBN
Albert Einstein, 14.03.1879-18.04.1955
1905:
- Über einen die Erzeugung und Verwandlung des Lichtes betreffenden heuristischen Gesichtspunkt- Die von der molekularkinetischen Theorie der Wärme geforderten Bewegung von in ruhenden Flüssigkeiten suspendierten Teilchen- Elektrodynamik bewegter Körper - Ist die Trägheit eines Körpers von seinem Energieinhalt abhängig?
1915:
Framework/Propositions
1. Einstein Equations Hold for Universe
2. Cosmological PrincipleHomogeneity & Isotropy of 3D
4. --> Friedmann Equations
3. Iso-entropic Expansion
Expanding Universe
larger e,p faster cooling:
Issues:
Nucleosynthesis: test of expansion dynamics
CMB: 300,000 years, Now:
Prior to Nucleosynthesis
1. Confinement: Hadrosynthesis
BK, Bluhm, 2005
2. Strongly Interacting Matterquarks
gluons
confinement
temperature evolution
strangeness evolution
strangeness changingweak interactions
3. Radiation Universe
Stretching of Distances
T = 170 MeV
5 m 1 fm100000 fm
1 fm
q
q
1 fm
g
1000 fm
q
T = 2.3 x 10 MeV-10
On average On Earth In nuclei & neutron stars
B B B
The Universe as Reactor
Friedmann: T(t) from
D: baryometer4He: chronometer
only destruction after BNN
Primordial Nuclear Network
2. D, 4. 3He, 8. T, 6. 4He, 7. 7Li
Dominant Channels (strong int./QCD):
T < 1 MeV: e+ e- annihilation (QED) nu decoupling (e.w. int.)
p
n
D T
He He
Be
Li
1
2
5
63 4 8
9
10
12
11
7
7
7
3 4
Nollett-Burles
Rate Equations for 2 2 Processes
rates (T)
Init. Conds.: earlier equilibrium values
add decays
integrate up to freeze-out
doneT(t)
Survey on Data Nollett-Burles 2000
freeze-in all other parametersand consider only the impact of thisreaction
poor data samples:
Evolution of Abundances
D
Be
mass fraction
Cosmic Concordance?
new physics beyond Standard Model?Xdimensions, more neutrinos, axions, SUSY particles, G(t), ...
WMAP: Precision Cosmology
time
BBN
Knowing only Photo Dissociation Data
Bisho
p 50
Shino
hara
49 de Graeve 92
Role of n(p,D)gamma
Knowing more Data
detailed balance:
Sn
p
D
error bars suppressed
EFT: the toolof strong interactionat low energiesadjusted to Cox 65
low energy:high energy:
N isovector mag. moment
Low Energy Data np D gamma
Bethe 49
data too scarce forprecision cosmology
new measurements at ELBEGrosse, Beyer & Co
„GamoW window“
FZ RossendorfELBEBremsstrahlung cave:
p
nD
1. D at rest: T_p, T_n
2. Superposition ofvarious beam energies thermal spectrum
A. Wagner
FZ RossendorfELBEnTOF cave
np
D
pulsed n source:
A. Junghans
1.E-02
1.E-01
1.E+00
1.E+01
1.E+02
1.E+03
1.E+04
1.E+05
1.E+06
1.E+07
1.E
-11
1.E
-10
1.E
-09
1.E
-08
1.E
-07
1.E
-06
1.E
-05
1.E
-04
1.E
-03
1.E
-02
1.E
-01
1.E
+00
1.E
+01
1.E
+02
En / MeV
Flu
x d
ensi
ty /
cm-2
s-1
No absorber5 cm PE + 5 mm Cd10 cm PE + 5 mm Cd2 mm PE + 0.5 mm Cd1 cm PE + 0.5 mm Cd
f = 1.6 MHzE = 210 keVt = 615 ns
J. Klug
Previous Measurements
Suzuki et al. 95:
Hara et al. 03:
Moreh et al. 89:
Nagai et al. 97:
Cokinos, Melkonian 77:
other exps.: M1 vs. E1
Xsection R factor Rate
ENDF
Using Rates in BBN123
5% lowering of 7Li (relative to SKM&EFT)
Sensitivity Function
measure here!
Neutron Life Time
nearly all n are in 4He: Y(4He) depends on(other abundances are robust) and also on
fastBBN
886.7869
904
Number of Light Neutrinos
3
3.5
2.5
Conclusions
more data for gamma D n pat E_gamma <,= 2.32 MeV:pin down primordial 7Li abundancebelow a 5% level
more precise data for other reactions& more precise observational data: NEW PHYSICS?
BBN vs. CMB
Deviations of Data and SKM(5): R Factor
13%
WM
AP
885.7 sec878.5 sec
Mathews,Kajino,Shima 05 Steigman 05
9 o
rder
s o
f m
agn
itu
de
BBN with eta(WMAP)
Hel
ium
-4
mas
s fr
actio
n
eta from BBNadjusted to obs.
Metal-poorExtragalactic H II regions
Deuteron Abundance: Observations
BBN witheta_10=6.1
X = metallicity (O,Si)
Impact of Changed Xsections10%
change of rate
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