Supernova effects on Server Sky and Stady Shell

The Sun's absolute bolometric (all band) magnitude is +4.74, 3.828e26 W, so an absolute magnitude of zero is 3.013e28 W.

Abs

Watts

10 pc

100 pc

Mag

W/m²

W/m²

-19

1.2e36

100

1.00

-18

4.8e35

40

0.40

-17

1.9e35

16

0.16

-16

7.6e34

6.3

63m

-15

3.0e34

2.5

25m

-14

1.2e34

1.0

10m

-13

4.8e33

0.4

4m

gamma and X rays

distance

sn1a

snII

2e34W

1e32W

pc

W/m²

W/m²

10

16.7m

84μ

30

1.86m

9.3μ

100

167μ

840n

300

18.6μ

93n

1000

1.67μ

8.4n

Type Ia

2e44 J

Supernovae Light Curves:

attachment:Comparative_supernova_type_light_curves.png

(by litopsian on Wikipedia)



Stellar evolution to supernova, and neutrino emissions

25 solar mass star

Burning
phase

Required
temperature
Kelvin

Required
mean density
kg/m3

Duration

Luminosity

neutrinos

Hydrogen

4e7

5e3

7 Myear

1.71 MeV per4 H

Helium

2e8

7e5

700 Kyear

Carbon

6e8

2e8

600 years

Neon

12e8

4e9

1 year

Oxygen

15e8

1e10

6 months

Silicon

27e8

3e10

1 day

from "Extreme Explosions" by David S. Stevenson, Multco 523.84465 S84746 2014


Neutrinos: "1 light year of lead" is 9.5e15 m times 11,000 kg/m3, or 1e20 kg/m2. In the pre-supernova silicon-burning phase, core density is 3e7 g/cm3 or 3e10 kg/m3, so a 3 million kilometer column of core would absorb a substantial fraction of neutrinos.

attachment:SNne.png


AL26

The 1.8 MeV gamma emission of 26Al decay to 26Mn tells us about galactic frequency of Type II supernovae, about 2 per century , estimated from the gamma emissions from the 26Al around us, about 2.8 solar masses in the galaxy (5.6e30 kg). One supernova produces 2.5e26 kg of 26Al. The half life of 26Al is 717 ky, so the decay rate is 3e-14 per second, or 7e11 decays/kg-s, or 0.2 W/kg. Assuming 0.04 c radial velocity, and isotropic deposition at a distance of 100 light years (9.4605e17m) 2500 years later (0.25% has decayed), the deposited material density is 2.2e-11 kg/m2, the radioactivity is 4e-12 W/m2 or 7.4 MeV/m2-s or about 4 decays per second. Not much.

At stadyshell distance from the sun, there will be some distortion of the shell density due to the solar magnetic field, which will deflect the beam somewhat.

Supernova (last edited 2021-02-07 22:12:06 by KeithLofstrom)