UPRM Center
Rafael Aramis López
LEAD TEACHER
UPRM Center
QuarkNet is a teacher
professional development
program funded by the
National Science
Foundation and the US
Department of Energy.
UPRM Center
QuarkNet brings high school
students and teachers to the
frontier of 21st century
research that seeks to
research some of the mysteries
about the structure of matter
and the fundamental forces of
nature.
UPRM Center
• Physicists mentor collaborate
with high school teachers.
•Teachers join research teams
with physicists at a local
university or laboratory.
•Students learn fundamental
physics as they analyze live
online data and participate in
inquiry-oriented investigations.
UPRM Center
Nosotros
Active QuarkNet Centers
Nosotros
Active QuarkNet Centers
QuarkNet centers are connected
to high-energy physics experiments
operating at CERN in Switzerland,
at Fermilab in Illinois, at SLAC in
Califormia and others. Within two
years, we expect to form 60
centers associated with research
groups at universities and labs
across the U.S.
People have long asked,
"Of what is the world made?"
and
"What holds it together?"
The word "fundamental" is key here.
By fundamental building blocks we mean objects that
are simple and structureless - not made of anything
smaller.
The ancient Greeks (@400 B.C.) are recognized for
the earliest attempts to describe the microstructure
of our Universe
• All substances were made of a basic
kind of matter called hulè.
• Matter is continuous and is made of
different combinations of 4 things:
earth, fire, air, and water.
• Aristotle’s major criticisms concerned
the idea that atoms moved through
empty space.
Democritus
The ancient Greeks (@400 B.C.) are recognized for
the earliest attempts to describe the microstructure
of our Universe
• Matter is made up of tiny individual
• All substances
particles were made of a basic
he named atomos.
kind of matter called hulè.
• Atomos could not be created, •destroyed
Matter is or
continuous and is made of
further divided.
different combinations of 4 things:
earth, fire, air, and water.
• Matter is also composed of empty space
through which atoms moved. • Aristotle’s major criticisms concerned
the idea that atoms moved through
empty space.
Democritus
HOT
DRY
MOIST
COLD
ARISTOTLE’S MATTER CONCEPT
DEMOCRITUS’ MATTER CONCEPT
ANTOINE LAVOISIER
The father of the chemistry
Considered as the
predecessor of the modern
chemistry, there realized
one of the most important
discoveries of this one
science, the Law of the
Conservation of the Mass.
3.Atoms
Atomsofofone
a given
element
are different
4.
element
with
atoms
5.
2.
1.All
Atoms
Elements
atoms
areof
indivisible
are
a given
composed
element
incombine
a chemical
of are
atoms
identical
process.
those
of anytoother
offrom
other
elements
formelement
compounds.
Dalton's Atomic Theory
DISCOVERY OF THE ELECTRON
In 1897, Joseph John Thompson discovered the first
component partof the atom: the electron, a particle with
a negative electric charge. In 1904, he proposed an
initial model of an atom, since nicknamed "Thompsons
pudding". He imagined the atom as a sphere full of an
electrically positive substance mixed with negative
electron "like the raisins in a cake".
J.J. Thomson's Cathode Ray Tube
DISCOVERY OF THE NUCLEUS
Ernest Rutherford discovered that the atom is mostly
empty space with a dense positively charged nucleus
surrounded by negative electrons The electron in an
atom moves around this nucleus like planets around the
Sun; which is where we get the name
“The atomic planetary model". .
BOHRS ATOM
In 1913 Niels Bohr created a new model of the atom:
The orbits of the electrons can't be just anywhere but
are "quantified"; only certain particular orbits are
permitted for the electron.
DISCOVERY OF NUCLEONS
Rutherford understood that the nucleus is itself
composed of nucleons. These nucleons are of two types:
•positively charged, it's a proton.
•neutrally charged, it's a neutron
The neutron was discovered in 1932 by James Chadwick.
The Charge-Cloud Model
The charge-cloud model,
which is also called the
quantum-mechanical
model, does not attempt
to describe the path of
each electron in a fixed
orbit. Scientists now
describe the possible
positions of electrons in
terms of probability.
Are the Nucleons Fundamental?
Physicists have discovered
that protons and neutrons
are composed of even
smaller particles called
quarks.
As far as we know, quarks
are like points in geometry.
They're not made up of
anything else.
If the protons and neutrons were a centimeter in diameter; Then
the electrons and quarks would be less than the diameter of a
hair; and The entire atom's diameter would be greater than the
length of 30 football fields! 99.99% of the atom is empty space
THE MODERN ATOM MODEL
Physicists have developed a theory called The
Standard Model that explains what the world is
and what holds it together. It is a simple and
comprehensive theory that explains all the
hundreds of particles and complex interactions
with only: •6 quarks.
•6 leptons. The best-known lepton is the electron.
•Force carrier particles, like the photon.
THE STANDARD MODEL
The Universe is made of Quarks and Leptons
Everything from galaxies to mountains to
molecules is made from quarks and leptons.
Quarks behave differently than leptons, and
for each kind of matter particle there is a
corresponding antimatter particle.
Matter and Antimatter
For every type of matter particle we've found, there
also exists a corresponding antimatter particle, or
antiparticle.
Antiparticles look and behave just like their
corresponding matter particles, except they have
opposite charges.
Quarks are one type of
matter particle. Most of
the matter we see around
us is made from protons
and neutrons, which are
composed of quarks.
BARYONS
qqq
+
+
=
+
1
electric
charge
THE PROTON
BARYONS
qqq
+
+
=
0
electric
charge
THE NEUTRON
MESONS
qq
anti
+
=
+
1
electric
charge
THE PION (
π+)
ANTIBARYONS
qqq
anti
anti
+
anti
+
=
1
electric
charge
THE ANTIPROTON
There are six leptons, three of which have electrical charge
and three of which do not. They appear to be point-like
particles without internal structure. The best known lepton
is the electron.The other leptons are the three types of
neutrinos. They have no electrical charge, very little mass.
LEPTONS
Periodic Table of Elements
What Powers the Sun?
Its Source of Energy
The Sun is a big thermonuclear reactor that
Gravitational
Chemical
Contraction?
Reaction?
works by converting hydrogen into helium.
The Sun’s Interior
The Core, at about 15,000,000 K, is the
source of the Sun’s energy.
The site of the thermonuclear fusion.
Its Source of Energy
Thermonuclear Fusion Reaction
4 1H --> 4He + energy
Energy Produced = 0.007(mass of 4 1H)c2
Solar Energy Production
To get the positively-charged nuclei to
fuse together, their electrical repulsion
must be overcome.
Solar Energy Production
1
2
3
4
Mass to Energy!
One
helium
nucleus hasthe
99.3%
of theof
weight
of four
hydrogen
nuclei.
We
can
calculate
amount
energy
create
from
the
The
creation
of
each
helium
nucleus
requires
four
hydrogen
nuclei.
This excess of 0.7% of hydrogen mass
excess of mass by using E=mc2. compared with helium mass is
converted into energy.
Solar Energy Production
The net result is
6 1H + 2 e --> 4He + 2 1H + 2 neutrinos + 6 photons
or
4 1H + 2 e --> 4He + 2 neutrinos + 6 photons
The net energy release is 26 MeV!
Ice Under Fire: Alaska
Alaska's glaciers are receding at twice the rate previously thought, according
to a new study published in the July 19, 2002 Science journal. These two
images show Portage Glacier, near Anchorage, Alaska, in 1914 and in 2004.
The ice has pulled back nearly out of sight.