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Home , Stellar nucleosynthesis

Stellar and

Miklós Kiss

Berze High School Gyöngyös

Károly Róbert Campus, Eszterházy Károly University Gyöngyös, Hungary

Lovas István (1931-2014)

Thanks to István Lovas, who encouraged and helped me get started with the research work.

I learned a lot from him about particles, as well.

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 2.

What makes hot?

(The gravitational contraction.)

What keeps a shining (radiating)?

( .)

What is a star?

(An object in which energy from nuclear reactions balances the radiation energy losses.)

Gravitational contraction is the driver of .

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 3. HRD

Absolute – Spectral type

Luminosity – Temperature (Color)

Stages of evolution

Main sequence Red-giant branch White-dwarf branch

Snapshot: evolutionary states of many stars

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 4. Interstellar medium

Gas

about 90% by number

about 9%

remaining 1% heavier elements

and

some dust

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 5. I.

Collapsing of an interstellar

Jeans criteria (energy, mass, length, density)

E tot = Ek + Egr < 0

The temperature - density diagram ( T −ρJ ) For a given Jeans mass

1 2 3 1 2fm  4πM  3 T =   ρ⋅   J k3  3 

Cooling or heating

Opacity, infrared radiation Fragmentation

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 6. Star formation II.

Infrared

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 7. Initial Mass Function (IMF)

IMF is an empirical function that describes the distribution of initial masses for a population of stars.

N = f (m) ⋅ m

−α f (m) = K ⋅ m ,

where

 ;3,0 m < ,0 08  α =  ,0;3,1 08 ≤ m < 5,0   ,2 35 5,0; m ≤ m

(Thanks to Szalai Tamás, University of Szeged)

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 8. Mass and Evolution

Minimum mass and maximum mass

Mmin ≈ ,0 08⋅ MSun

Mmax ≈100⋅ MSun

(S. G. Ryan, A.J. Norton: Stellar Evolution and Nucleosynthesis, Cambridge 2010)

Star states

star red- white-dwarf star star supernovae: SNI, SNII and some other

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 9. Mass depending stellar evolution

11 M ☉-

8 M ☉-11 M ☉

0,5 M ☉-8 M ☉

0,08 M ☉-0,5 M ☉

0,0125 M ☉-0,08 M ☉

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 10. Nucleosynthesis

1. Nucleosynthesis

2.

a, fusion

b, nucleosynthesis

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 11.

H, He p:n = 8:1 so

H:He= 14:2 that is YHe~0,22.

Recently YHe ~0,23. All hydrogen is from BBN and the vast majority of helium.

4He, D, 3He and 7Li They were produced during the first 20 minutes of the when it was dense and hot enough for nuclear reactions to take place.

Besides these , some minute traces of 6Li, 9Be, 11 B and CNO are produced by BBN.

(Alain Coc: arXiv:1208.4748v1)

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 12. Stellar Nucleosynthesis: Fusion

He: p-p

CNO

Heavier nuclei:

3α

Formation of 12 C: crucial step: Beryllium dynamic equilibrium (-time ~ 10 -16s)

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 13. Neutron Capture Nucleosynthesis

Processes:

s-process

r-process

and

m-process (i-process)

There is band instead of path!

The beginning of the neutron capture nucleosynthesis

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 14. The profile of neutron capture band at isotopes

( n8 =108 cm−3 )

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 15. Neutron source and mass

The two main processes:

and

The first process occurs in massive helium burning stars and in AGB TP,

the second occurs in AGB stars at the TDU following the TP

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 16. Individual abundance

Change the nucleon identification from the usual (Z,A) to (Z,N). This will allow us to read new information from the various measured abundances.

Charts with isotopic and individual abundance notation For example 96 Zr has 2.80 percents isotopic abundance and 98 Mo has 24.13 percents. But individual abundances are 0,32 and 0,605. So such way one can see the real ratio between them.

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 17. Rate Analysis

1. Traditional approach "The success of any theory of nucleosynthesis has to be measured by comparison with the abundance patterns observed in ." say Käppeler, Beer and Wisshak , that is, we need to create such model that gives back the observed abundance.

(F. Käppeler, H. Beer and K. Wisshak, s-process nucleosynthesis- and the classical model: Rep. Prog. Phys. 52 (1989) 945-1013.)

2. New point of view It seems that the reverse approach is also useful: the abundance is the preserver of the nuclei’s formation conditions. So instead investigating whether the theoretical model fits the observed abundance, we look for the circumstances when the observed abundance is available.

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 18. Isotopic case

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 19. Isotonic case

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 20. The existence of 60 Fe radioisotope

The 59 Co and 60 Fe abundance at different neutron density. The figure shows the difference between PFR and the branching factor

PFR: Partial Formation Ratio (M. Kiss, Rate Analysis or a Possible Interpretation of Abundances PoS(NIC XIII)110)

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 21. Paths

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 22. AGB

All experienced ratios can be obtained both at 108 K temperature and at 3⋅108 K temperature at intermediate neutron density

12 14 −3 n n =10 −10 cm

so the m-process and the AGB stars are probably one of the main places of nucleosynthesis.

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 23. WD initial mass – final mass estimation

For a WD the minimal mass is 0,4 M☉, the maximal mass less than M Ch .

MCh .= 1,4 M☉

M(final) = ,0 0988⋅M(initial) + ,0 4087 M☉

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 24. How much matter (mass) was in an AGB star?

How many stars are between m1 and m2 ? About IMF:

m m2 m2  m1−α  2 K N = f (m)dm = K ⋅ m−α dm = K = ()m 1−α − m 1−α ∫ ∫ 1−α  1−α 2 1 m1 m1   m1

But, how much mass is between m1 and m2 ?

m m2 m2  m2−α  2 K m = g(m)dm = K ⋅ m1−α dm = K = ()m 2−α − m 2−α ∫ ∫ 2 −α  2 −α 2 1 m1 m1  m1

About these and the WD initial – final mass estimation:

From the whole initial mass 64% were in an AGB star, and during the mass loss 37% mass returned into the ISM. At SNII from the initial mass only 19% mass returned into the ISM. 10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 25. SNI SNII

before SN after SN

light curves are different for SNI and SNII

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 26. SNII

SN 1987a

“Approximately two to three hours before the visible light from SN 1987A reached Earth, a burst of was observed at three separate observatories. This is likely due to neutrino emission, which occurs simultaneously with core collapse, but preceding the emission of visible light. Transmission of visible light is a slower process that occurs only after the reaches the stellar surface. At 07:35 UT, Kamiokande II detected 12 antineutrinos ; IMB, 8 antineutrinos; and Baksan, 5 antineutrinos; in a burst lasting less than 13 seconds. Approximately three hours earlier, the Mont Blanc liquid scintillator detected a five-neutrino burst, but this is generally not believed to be associated with SN 1987A"

(https://en.wikipedia.org/wiki/SN_1987A)

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 27. Crab Nebula: SN 1054

Distance: 6500 LY in the centre there is a -> SN II

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 28. SNIa Binary stars, CO and its companion star

Supernovae – star explosions – became the new standard candles. http://www.nobelprize.org/nobel_prizes/physics/laureates/2011/popular-physicsprize2011.pdf

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 29. POP I-II-III.

POP I the recent stars in the spiral arms of

POP II the oldest star in the Galaxy near the centre of Galaxy

POP III formed from primordial H and He probably extremely massive, extreme poor.

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 30. Cycling

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 31.

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 32.

Thank You for Your Attention!

10 th Bolyai-Gauss-Lobachevsky conference 08. 24. 2017. KRC EKU Gyöngyös Miklós Kiss, Berze High School Gyöngyös 33.