Karlsruhe Astrophysical Database of Nucleosynthesis in Stars
s-process
[Standards]   [Logbook]   [FAQ]   [Links]   [Contact]
p-process
Available isotopes for Helium (Z=2)
  3He
Go to isotope
Recommended MACS30 (Maxwellian Averaged Cross Section @ 30keV)
3He 4He




Cross sections do not include stellar enhancement factors!
History
VersionTotal MACS [mb]Partial to gs [mb]Partial to isomer [mb]
0.00.0076 ± 0.0006--

(Version 0.0 corresponds to Bao et al.)
Comment
Last review: 1999
List of all available values
originalrenorm.yeartypeCommentRef
0.0091 ± 0.0008
24.5keV
0.00761991cF.N.B., Act., 1/v(E) Au: 623 (9)mb(24.5keV)WAP91
0.012 ± 0.006
25keV
1979cABW79
0.0000248
2006eendfb7
0.0000248
2004ejeff31
0.0163
2002ejendl33


Original:MACS [<σ v>/vT] (mb) for kT=30 keV, based on the published cross sections except where indicated otherwise.
Renorm:MACS [<σ v>/vT] (mb) for kT=30 keV for which the reference or standard cross section was meanwhile improved.
Type: The letters and numbers in the column labelled 'type' give information on how the cross section has been obtained:
cDirectly quoted from the reference itself
eEvaluated value taken directly from the reference
MACS, SEF and Reaction Rates for different energies
Energy30keV
MACS
0.0076 ± 0.0006
SEF1.00
Rate
1.27

MACS:
Reference: WAP91
Procedure: 'e' (The Maxwellian-averaged cross sections (MACS) from kT=5 keV to 100 keV are obtained from experimental data; the relative uncertainties are similar to those quoted for the 30 keV data.)
Year: 1991

SEF (Stellar enhancement factor):
Reference: Rau09
Year: 2009
Comment:
. Please note: SEF for this element have not been calculated but are expected to be close to 1.
Rate:
Reaction rate NA<σv> given in 103 cm3/mole/s, including SEF
Isotopic mass chain
Isotopic Mass Chain
Chart of nuclei
up
left
6Be
0.00 ms
P
7Be
53.22 d
β+
4Li
0.00 ms
P
5Li
0.00 ms
α
6Li
7.59%
3He
0.000137%
0.0076 mb
4He
99.9999%
5He
0.00 ms
α
1H
99.985%
0.254 mb
2H
0.015%
3H
12.32 a
β-
4H
0.00 ms
N
1Nn
10.24 m
β-
right
down
Style: (Size: S, M, L, XL, Alberto; No-Macs: nox)


Isotope: Helium