Sunday, October 31, Cooking With The Stars

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Dominick Ramsey
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1 Cooking With The Stars

2 What are we made of? Veggies

3 What are we made of? Poutine

4 What are we made of? Liver Fava beans..and a nice Chianti

6 Element % (no. of atoms) How they were made Hydrogen 61.6 Big Bang Oxygen 26.3 Carbon 9.99 Nitrogen 1.48 Calcium 0.24 Phosphorus 0.20 Sulphur 0.06 Sodium 0.06 Chlorine 0.04 Magnesium 0.03?????????

7 Nuclei Rutherford Nuclear Safety Officer

Rutherford s Discovery - 1911 Nucleus If an atom were as

9 Rutherford s Discovery Nucleus If an atom were as large as the McGill campus, the nucleus would be the size of a dime

10 Basic Ingredients + proton neutron free protons live forever, but neutrons decay in about 10 minutes 10

11 Basic Ingredients + proton + - proton Beta decay of the neutron 11

12 Carbon-11 with too many protons

13 changes to boron-11 by emitting a positron +

14 Lithium-11 with too many neutrons

15 Changes to beryllium - 11 by emitting an electron -

16 proton neutron The simplest nuclear reaction: a proton meets a neutron

19 E = mc 2

20 If we could weigh nuclear particles we could calculate the energy released

J.J. Thompson - 1897 -discovery and mass of

21 J.J. Thompson discovery and mass of the electron- This was the first mass spectrometer

22 Argonne National Laboratory 22

23 The Canadian Penning Trap

24 Making proton-rich isotopes by collisions from ATLAS nickel carbon germanium-68 Making neutron-rich isotopes by californium fission californium-252

25 Ion Trap from ion guide

26 +ve caps keep the ion from escaping axially

27 magnetic field B + - magnetic field keeps the ion from escaping radially

28 magnetic field B r rotation speed = constant x qb/m

29 detector Measuring the frequency - + -kick the ions out of the trap -the ones that have spun in the field arrive first

30 4 beryllium 3 lithium number of protons 2 1 proton deuteron neutron alpha-particle helium hydrogen number of neutrons

31 ! # %& () + (, +,./0, Chart of Nuclides 34823<< Ν ϑο.1:2..4 Π> ? ?Β Number of Protons (Element) 4. fusion reactions in ordinary stars can only make these elements :62<4?+ :.2<6 ;> ! ::2311 > =& 51 8<251 = 8629: ; Β : ΑΒ Γ& < Φ Ε :< ΝΟ 34823<4 Μ ΜΚ !& =, Χ :6 Λ : :. Φ> 39<2365 ϑκ ΗΙ )Ε.1.2.1< % 3<12.39 Μ+ 34:2.14 ) % Number of Neutrons

32 Ordinary stars can t make these by fusion must be made by other processes

35 Supernova 1987a - before and after

37 X-ray bursts on a neutron star

39 Understanding Stellar Cooking We need measurements masses for energy differences decay lifetimes proton, neutron capture rates rp-process protons r-process neutrons

40 rp-process measurements using the ATLAS beam endpoint midpoint More than 40 proton-rich nuclides measured over the past few years Most masses were determined to better than 10 kev/c 2 G. Audi et al., Nucl. Phys. A 729, 337 (2003).

41 Californium Fission Text 252 Cf fission branch >

42 252 Cf fission branch >

r-process measurements using the californium source New CPT / Previous CPT measurements Ongoing program of measurements since March 2008, target 15 kev uncertainty 40

43 r-process measurements using the californium source New CPT / Previous CPT measurements Ongoing program of measurements since March 2008, target 15 kev uncertainty 40 species, 5 have never been previously measured by any means, most others improved by a typical factor of 5 Adds to 30 measurements taken at CPT in past years with small gas catcher

44 CARIBU Californium-252 one curie source

46 Mass Measurement Penning Trap Facilities Operating Under Construction Planned

Basic Nuclear Theory. Lecture 1 The Atom and Nuclear Stability

Basic Nuclear Theory. Lecture 1 The Atom and Nuclear Stability Basic Nuclear Theory Lecture 1 The Atom and Nuclear Stability Introduction Nuclear power is made possible by energy emitted from either nuclear fission or nuclear fusion. Current nuclear power plants utilize