explosions
in our data
Federica B. Bianco
University of Delaware
Physics and Astronomy
Biden School of Public Policy and Administration
Data Science Institute
NYU Center for Urban Science and Progress
Rubin Observatory LSST Science Collaborations Coordinator
Rubin LSST Transients and Variable Stars Science Collaborations Chair
From Flammarion's Astronomie Populaire (1880): in Scania, Denmark
Workshop of Diebold Lauber unknown artist, ca.1450
White Tanks Regional Park, Phoenix, AZ
Title Text
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SN 185
SN 393
SN 1006
SN 1054
SN 1181
Tycho SN
Kepler SN
Cas A
SNLS/SDSS
PTF
ZTF
Rubin LSST
starting in
2023
100 Msun
0.08 Msun
mass
slow death fading away
explosive death
Twinkle twinkle little star
I'm aware of what you are
you are a glowing ball of gas
how you live depends on mass
Adapted from Prof. Viviana Aquaviva, CUNY
luminosity
temperature
lives of stars
Just like stars in Hollywood :
the biggest stars live fast and die young and spectacularly
Gravity is pushing in
Nuclear reactions push the star outward
H->He->C->N->O->…Fe
Hydrostatic Equilibrium
Nuclear reactions push the star outward
Elements up to iron are forged in star cores.
Iron is so tightly bound that it absorbs energy instead of generating it in fusion : temperature drops instead of rising, gravitational pressure wins
I. we are made of star dust
high initial mass
8-100 MSun
live fast and die in spectacular explosions
lives of stars
….. live to be old and die peacefully by slowly cooling down
low initial mass
0.1-8 MSun
lives of stars
White Dwarf: supported by electron degenerate pressure - The Pauli exclusion principle states that no two electrons with the same spin can occupy the same energy state in the same volume.
Maximum mass: Chandrasekhar limit M = 1.44 MSun
Neutron star: supported by neutron degenerate pressure - The Pauli exclusion principle exists for neutrons as well.
1 Earth radius
size of manhattan
Black hole
star remnants:
extreme physics environments
low initial mass but with a sibling
even a low mass start will explode if its in a binary system and captures mass from the companion
lives of stars
high initial mass
8-100 MSun
might collapse directly into a black hole
lives of stars
Reason to study Supernovae
SN are enable life in the Universe
SN are natural extreme physics laboratories
SN trace the evolution of the Universe
I. we are made of star dust
“The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, the carbon in our apple pies were made in the interiors of collapsing stars.
We are made of starstuff.”
― Carl Sagan, Cosmos
Elements up to iron are forged in star cores.
Heavier elements, particularly Nickel and Cobalt, are forged in the explosion.
More powerful explosions generate yet heavier elements.
All are released into outer space in stellar explosions and eruptions
I. we are made of star dust
Pankey, Titus, Jr.
Howard University thesis
Possible Thermonuclear Activities in Natural Terrestrial Minerals. 1962
II. understanding extreme physics
SN lightcurves
II. understanding extreme physics
typical energy released:
1 Megaton bomb would distroy everything in an 80km radius
II. understanding extreme physics
II. understanding extreme physics
SN spectra
III. they tell us fundamental things about the Universe
Farthest SN
10.5 billion years ago
3 billion years after the Big Bang
redshift 4
III. they tell us fundamental things about the Universe
luminosity ~ time
III. they tell us fundamental things about the Universe
stellar explosions are enable life in the Universe
stellar explosions are natural extreme physics laboratories
stellar explosions trace the evolution of the Universe
contact me!
fbianco@udel.edu
University of Delaware
Rubin LSST
Science Collaborations
Transients and
Variable Stars
Science Collaborations
II. understanding extreme physics
SN 2011dh, M51
vanDyk et al. 2011