Asked 11th May, 2019

Where can I find the astrophysical S-factors for those thermonuclear reactions that produce electron neutrinos?

Astrophysical S-factors for thermonuclear reactions that produce electron neutrinos.

All Answers (2)

although not specific to neutrino reactions, there are experimental databases of the S-factor for most astrophysical nuclear reactions, as:
and also theoretical predictions by nuclear models (see for example: )
Kind regards.
13th May, 2019
Camilo Agudelo
Universidad Santiago de Cali
Good morning Dr. Fontana.
Thank you for your information, I appreciate it. I have been reading the article you just shared and it is really helpful. I was wondering if you have some information about the Astrophysical S-factor when it is evaluated in the gamow peak (S(E_0)). I checked a couple of articles and they had the value for some neutrino reactions, but not all of them. I have e.g. p + p, but they do not have the rest of them. I'd appreciate it if you may give me a hand with this, because I've been stuck at this and also need an expression for events number in a solar neutrino detector.
Thank you very much.
Best regards.

Similar questions and discussions

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  • Ki Chul KimKi Chul Kim
While I looked through a set of commands which has to be included for each of hybrid functionals, I found some weird information.
VASP wiki site suggests us to use the following commands for PBE0 functional.
AEXX=0.25, AGGAX=0.75, AGGAC=1.0 and ALDAC=1.0
Most of other hybrid functionals (HSE03, HSE06) are also suggested to use AGGAC=1.0 and ALDAC=1.0.
I could guess from this information (AGGAC=1.0; ALDAC=1.0) that AGGAC means just a gradient correction itself introduced to LDA.
Therefore, in my opinion, GGA (AGGAC=1.0 and ALDAC=1.0) contains the contributions of both the electron density and the gradient of the electron density to the correlation energy.
In contrast, AGGAC=1.0 and ALDAC=0.0 indicates the contribution of the electron density gradient only to the correlation energy.
I think that this is the main reason why VASP wiki suggest AGGAC=1.0 and ALDAC=1.0 instead of AGGAC=1.0 and ALDAC=0.0.
However, my understanding constructed on the basis of the afore-mentioned information has been messed up due to the commands for B3LYP.
VASP wiki site suggests us to use the following commands for B3LYP functional.
GGA = B3
AEXX = 0.2
AGGAX = 0.72
AGGAC = 0.81
ALDAC = 0.19
I have no idea of why the site suggests ALDAC=0.19 instead of ALDAC=1.0, although B3LYP uses the combination of the purely electron density-based correlation energy (LDA) of 19% and the gradient-corrected LDA correlation energy (GGA) of 81% by definition.
I think AGGAC=0.81 and ALDAC=0.19 means LDA of 19% and just gradient correction of 81%.

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