The Birth, Life, and Death of Starsweb2.physics.fsu.edu/~piekarewicz/OLLI-Lecture4.pdf · physics of therelativisticdegenerate electron gas in white dwarf stars(at the age of 19!)

The Birth, Life, and Death of Stars

The Osher Lifelong Learning InstituteFlorida State University

Jorge PiekarewiczDepartment of [email protected]

Schedule: September 29 – November 3Time: 11:30am – 1:30pm

Location: Pepper Center, Broad Auditorium

J. Piekarewicz (FSU-Physics) The Birth, Life, and Death of Stars Fall 2014 1 / 17

Ten Compelling Questions

What is the raw material for making stars and where did it come from?What forces of nature contribute to energy generation in stars?How and where did the chemical elements form? ?How long do stars live?How will our Sun die?How do massive stars explode? ?What are the remnants of such stellar explosions?What prevents all stars from dying as black holes?What is the minimum mass of a black hole? ?What is role of FSU researchers in answering these questions?

A Star is BornThe Universe was created about 13.7 billion years ago (Big Bang!)

H, He, and traces of light elements formed 3 minutes after the Big Bang (BBN)

Stars and galaxies form from H and He clouds about 1 billion years after BB

In stellar nurseries molecular clouds convert gravitational energy into thermal energy

At about 10 million K protons overcome their Coulomb repulsion and fuse (pp chain)

p + p → d + e+ + νep + d → 3He + γ3He + 3He→ 4He + p + p

ALL (gravity, strong, electroweak) interactions critical to achieve stardomThermonuclear fusion halts the gravitational collapse

Stellar evolution continues through several thermonuclear stages

Stellar Nucleosynthesis

Stars are incredibly efficient thermonuclear furnacesAfter H-burning terminates the stellar core contractsGravitational energy is transformed into thermal energyThe heavier He-ashes (with a larger Z ) can now fuse

Thermonuclear fusion continues until the formation of an Iron coreThermonuclear fusion terminates abruptly: Supernova!Every C in our cells, O in the air, and Fe in our blood was made in stars

We all truly are “star stuff”...Carl Sagan

Death of a Star — Birth of a Pulsar: Core-Collapse Supernova

Massive stars create all chemical elements: from 6Li to 56Fe

Once 56Fe is produced the stellar core collapses

Core overshoots and rebounds: Core-Collapse Supernova!

99% of the gravitational energy radiated in neutrinos

An incredibly dense object is left behind: A neutron star or a black hole

Neutron stars are solar mass objects with 10 km radiiCore collapse mechanism and r-process site remain uncertain!

Some Historical Facts

Chandrasekhar shows that massive stars will collapse (1931)Chadwick discovers the neutron (1932)... predicted earlier by Ettore Majorana but never published!Baade and Zwicky introduce the concept of neutron stars (1933)Oppenheimer-Volkoff compute masses of neutron stars using GR (1939)Predict M?'0.7 M� as maximum NS mass or minimum black hole massJocelyn Bell discovers pulsars (1967)Gold and Pacini propose basic lighthouse model (1968)Pulsars are rapidly rotating Neutron Stars!

S. Chandrasekhar and X-Ray ChandraWhite dwarfs resist gravitational collapse through electron degeneracy pressure ratherthan thermal pressure (Dirac and R.H. Fowler 1926)

During his travel to graduate school at Cambridge under Fowler, Chandra works out thephysics of the relativistic degenerate electron gas in white dwarf stars (at the age of 19!)

For masses in excess of M =1.4 M� electrons becomes relativistic and the degeneracypressure is insufficient to balance the star’s gravitational attraction (P∼n5/3 →n4/3)“For a star of small mass the white-dwarf stage is an initial step towards completeextinction. A star of large mass cannot pass into the white-dwarf stage and one is leftspeculating on other possibilities” (S. Chandrasekhar 1931)

Arthur Eddington (1919 bending of light) publicly ridiculed Chandra’s on his discovery

Awarded the Nobel Prize in Physics (in 1983 with W.A. Fowler)

In 1999, NASA lunches “Chandra” the premier USA X-ray observatory

Jocelyn BellWorked with Anthony Hewish on constructing a radio telescope to study quasars

In 1967 as a graduate student (at the age of 24!) detected a bit of “scruff”

The Sounds of Pulsars

Jocelyn Bell discovers amazing regularity in the radio signals (P=1.33730119 s)

Speculated that the signal might be from another civilization (LGM-1)Paper announcing the first pulsar published in Nature (February 1968)A Hewish, S J Bell, J D H Pilkington, P F Scott, R A Collins

Antony Hewish and Martin Ryle awarded the Nobel Prize in Physics in 1974

The “No-Bell” roundly condemned by many astronomers (Fred Hoyle)

“I believe it would demean Nobel Prizes if they were awarded to research students, exceptin very exceptional cases, and I do not believe this is one of them”

http://www.jb.man.ac.uk/research/pulsar/Education/Sounds

Jocelyn BellWorked with Anthony Hewish on constructing a radio telescope to study quasars

In 1967 as a graduate student (at the age of 24!) detected a bit of “scruff”

The Sounds of Pulsars

Jocelyn Bell discovers amazing regularity in the radio signals (P=1.33730119 s)

Speculated that the signal might be from another civilization (LGM-1)Paper announcing the first pulsar published in Nature (February 1968)A Hewish, S J Bell, J D H Pilkington, P F Scott, R A Collins

Antony Hewish and Martin Ryle awarded the Nobel Prize in Physics in 1974

The “No-Bell” roundly condemned by many astronomers (Fred Hoyle)

“I believe it would demean Nobel Prizes if they were awarded to research students, exceptin very exceptional cases, and I do not believe this is one of them”

http://www.jb.man.ac.uk/research/pulsar/Education/Sounds

Biography of a Neutron Star: The Crab Pulsar

SN 1054 first observed as a new “star” in the sky on July 4, 1054Event recorded in multiple Chinese and Japanese documentsEvent also recorded by Anasazi residents of Chaco Canyon, NMCrab nebula and pulsar became the SN remnants

Name: PSR B0531+21 Distance: 6,500 lyPOB: Taurus Temperature: 106 KMass: 1.4 M� Density: 1014g/cm3

Radius: 10 km Pressure: 1029 atmPeriod: 33 ms Magnetic Field: 1012 G

A Grand Challenge: How does subatomic matter organize itself?“Nuclear Physics: Exploring the Heart of Matter” (2010 Committee on the Assessment and Outlook for Nuclear Physics)

Consider A nucleons and Z electrons in a fixed volume V at T ≡0... cold fully catalyzed matter in thermal and chemical equilibriumEnforce charge neutrality protons = electrons + muonsEnforce chemical (i.e., beta) equilibrium: n→p+e−+ν̄; p+e−→n+ν

Impossible to answer such a question under normal laboratoryconditions — as such a system is in general unbound!

Gravitationally Bound Neutron Stars as Physics Gold MinesNeutron Stars are bound by gravity NOT by the strong forceNeutron Stars satisfy the Tolman-Oppenheimer-Volkoff equationGR extension of Newtonian gravity: vesc/c ∼ 1/2Only Physics sensitive to is: Equation of StateEOS must span 10-11 orders of magnitude in baryon densityIncrease from 0.7→2M� must be explained by Nuclear Physics!

common feature of models that include the appearance of ‘exotic’hadronic matter such as hyperons4,5 or kaon condensates3 at densitiesof a few times the nuclear saturation density (ns), for example modelsGS1 and GM3 in Fig. 3. Almost all such EOSs are ruled out by ourresults. Our mass measurement does not rule out condensed quarkmatter as a component of the neutron star interior6,21, but it stronglyconstrains quark matter model parameters12. For the range of allowedEOS lines presented in Fig. 3, typical values for the physical parametersof J1614-2230 are a central baryondensity of between 2ns and 5ns and aradius of between 11 and 15 km, which is only 2–3 times theSchwarzschild radius for a 1.97M[ star. It has been proposed thatthe Tolman VII EOS-independent analytic solution of Einstein’sequations marks an upper limit on the ultimate density of observablecold matter22. If this argument is correct, it follows that our mass mea-surement sets an upper limit on this maximum density of(3.746 0.15)3 1015 g cm23, or ,10ns.Evolutionary models resulting in companion masses.0.4M[ gen-

erally predict that the neutron star accretes only a few hundredths of asolar mass of material, and result in a mildly recycled pulsar23, that isone with a spin period.8ms. A few models resulting in orbital para-meters similar to those of J1614-223023,24 predict that the neutron starcould accrete up to 0.2M[, which is still significantly less than the>0.6M[ needed to bring a neutron star formed at 1.4M[ up to theobserved mass of J1614-2230. A possible explanation is that someneutron stars are formed massive (,1.9M[). Alternatively, the trans-fer of mass from the companion may be more efficient than currentmodels predict. This suggests that systems with shorter initial orbitalperiods and lower companion masses—those that produce the vastmajority of the fully recycled millisecond pulsar population23—mayexperience even greater amounts of mass transfer. In either case, ourmass measurement for J1614-2230 suggests that many other milli-second pulsars may also have masses much greater than 1.4M[.

Received 7 July; accepted 1 September 2010.

1. Lattimer, J. M. & Prakash, M. The physics of neutron stars. Science 304, 536–542(2004).

2. Lattimer, J. M. & Prakash, M. Neutron star observations: prognosis for equation ofstate constraints. Phys. Rep. 442, 109–165 (2007).

3. Glendenning, N. K. & Schaffner-Bielich, J. Kaon condensation and dynamicalnucleons in neutron stars. Phys. Rev. Lett. 81, 4564–4567 (1998).

4. Lackey, B. D., Nayyar, M. & Owen, B. J. Observational constraints on hyperons inneutron stars. Phys. Rev. D 73, 024021 (2006).

5. Schulze, H., Polls, A., Ramos, A. & Vidaña, I. Maximummass of neutron stars. Phys.Rev. C 73, 058801 (2006).

6. Kurkela, A., Romatschke, P. & Vuorinen, A. Cold quark matter. Phys. Rev. D 81,105021 (2010).

7. Shapiro, I. I. Fourth test of general relativity. Phys. Rev. Lett. 13, 789–791 (1964).8. Jacoby, B.A., Hotan, A., Bailes,M., Ord, S. &Kulkarni, S.R. Themassof amillisecond

pulsar. Astrophys. J. 629, L113–L116 (2005).9. Verbiest, J. P. W. et al. Precision timing of PSR J0437–4715: an accurate pulsar

distance, a high pulsarmass, and a limit on the variation of Newton’s gravitationalconstant. Astrophys. J. 679, 675–680 (2008).

10. Hessels, J.et al. inBinaryRadio Pulsars (edsRasio, F. A.&Stairs, I. H.)395 (ASPConf.Ser. 328, Astronomical Society of the Pacific, 2005).

11. Crawford, F. et al. A survey of 56midlatitude EGRET error boxes for radio pulsars.Astrophys. J. 652, 1499–1507 (2006).

12. Özel, F., Psaltis, D., Ransom, S., Demorest, P. & Alford, M. The massive pulsar PSRJ161422230: linking quantum chromodynamics, gamma-ray bursts, andgravitational wave astronomy. Astrophys. J. (in the press).

13. Hobbs, G. B., Edwards, R. T. & Manchester, R. N. TEMPO2, a new pulsar-timingpackage - I. An overview.Mon. Not. R. Astron. Soc. 369, 655–672 (2006).

14. Damour, T. & Deruelle, N. General relativistic celestial mechanics of binarysystems. II. The post-Newtonian timing formula. Ann. Inst. Henri Poincaré Phys.Théor. 44, 263–292 (1986).

15. Freire, P.C.C.&Wex,N.Theorthometricparameterisationof theShapirodelay andan improved test of general relativity with binary pulsars.Mon. Not. R. Astron. Soc.(in the press).

16. Iben, I. Jr & Tutukov, A. V. On the evolution of close binaries with components ofinitial mass between 3 solar masses and 12 solar masses. Astrophys. J Suppl. Ser.58, 661–710 (1985).

17. Özel, F. Soft equations of state for neutron-star matter ruled out by EXO 0748 -676. Nature 441, 1115–1117 (2006).

18. Ransom, S. M. et al. Twenty-one millisecond pulsars in Terzan 5 using the GreenBank Telescope. Science 307, 892–896 (2005).

19. Freire, P. C. C. et al. Eight new millisecond pulsars in NGC 6440 and NGC 6441.Astrophys. J. 675, 670–682 (2008).

20. Freire, P. C. C.,Wolszczan, A., vandenBerg,M.&Hessels, J.W. T. Amassiveneutronstar in the globular cluster M5. Astrophys. J. 679, 1433–1442 (2008).

21. Alford,M.etal.Astrophysics:quarkmatterincompactstars?Nature445,E7–E8(2007).22. Lattimer, J. M. & Prakash, M. Ultimate energy density of observable cold baryonic

matter. Phys. Rev. Lett. 94, 111101 (2005).23. Podsiadlowski, P., Rappaport, S. & Pfahl, E. D. Evolutionary sequences for low- and

intermediate-mass X-ray binaries. Astrophys. J. 565, 1107–1133 (2002).24. Podsiadlowski, P. & Rappaport, S. CygnusX-2: the descendant of an intermediate-

mass X-Ray binary. Astrophys. J. 529, 946–951 (2000).25. Hotan, A.W., van Straten,W. &Manchester, R. N. PSRCHIVE andPSRFITS: an open

approach to radio pulsar data storage and analysis. Publ. Astron. Soc. Aust. 21,302–309 (2004).

26. Cordes, J.M. & Lazio, T. J.W.NE2001.I. A newmodel for theGalactic distribution offree electrons and its fluctuations. Preprint at Æhttp://arxiv.org/abs/astro-ph/0207156æ (2002).

27. Lattimer, J. M. & Prakash, M. Neutron star structure and the equation of state.Astrophys. J. 550, 426–442 (2001).

28. Champion, D. J. et al. An eccentric binary millisecond pulsar in the Galactic plane.Science 320, 1309–1312 (2008).

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Supplementary Information is linked to the online version of the paper atwww.nature.com/nature.

Acknowledgements P.B.D. is a Jansky Fellow of the National Radio AstronomyObservatory. J.W.T.H. is a Veni Fellow of The Netherlands Organisation for ScientificResearch.We thankJ. Lattimer for providing theEOSdataplotted inFig. 3, andP. Freire,F. Özel and D. Psaltis for discussions. The National Radio Astronomy Observatory is afacility of the USNational Science Foundation, operated under cooperative agreementby Associated Universities, Inc.

Author Contributions All authors contributed to collecting data, discussed the resultsand edited themanuscript. In addition, P.B.D. developed theMCMCcode, reduced andanalysed data, and wrote the manuscript. T.P. wrote the observing proposal andcreated Fig. 3. J.W.T.H. originally discovered thepulsar.M.S.E.R. initiated the survey thatfound the pulsar. S.M.R. initiated the high-precision timing proposal.

Author Information Reprints and permissions information is available atwww.nature.com/reprints. The authors declare no competing financial interests.Readers are welcome to comment on the online version of this article atwww.nature.com/nature. Correspondence and requests for materials should beaddressed to P.B.D. ([email protected]).

0.07 8 9 10 11

Radius (km)12 13 14 15

0.5

1.0

1.5

2.0

AP4

J1903+0327

J1909-3744

systemsDouble neutron sDouble neutron star sysy

J1614-2230

AP3

ENG

MPA1

GM3

GS1

PAL6

FSUSQM3

SQM1

PAL1

MS0

MS2

MS1

2.5 GR

Causali

ty

Rotation

P < ∞

Mass

(M

()

Figure 3 | Neutron star mass–radius diagram. The plot shows non-rotatingmass versus physical radius for several typical EOSs27: blue, nucleons; pink,nucleons plus exoticmatter; green, strange quarkmatter. The horizontal bandsshow the observational constraint from our J1614-2230 mass measurement of(1.976 0.04)M[, similar measurements for two other millisecond pulsars8,28

and the range of observed masses for double neutron star binaries2. Any EOSline that does not intersect the J1614-2230 band is ruled out by thismeasurement. In particular, most EOS curves involving exotic matter, such askaon condensates or hyperons, tend to predict maximum masses well below2.0M[ and are therefore ruled out. Including the effect of neutron star rotationincreases themaximum possiblemass for each EOS. For a 3.15-ms spin period,this is a=2% correction29 and does not significantly alter our conclusions. Thegrey regions show parameter space that is ruled out by other theoretical orobservational constraints2. GR, general relativity; P, spin period.

LETTER RESEARCH

2 8 O C T O B E R 2 0 1 0 | V O L 4 6 7 | N A T U R E | 1 0 8 3

dMdr

= 4πr2E(r)

dPdr

= −GE(r)M(r)r2

[1 +

P(r)E(r)

][1 +

4πr3P(r)M(r)

] [1− 2GM(r)

r

]−1Need an EOS: P =P(E) relation

Nuclear Physics Critical

The Anatomy of a Neutron Star

Atmosphere (10 cm): Shape of Thermal Radiation (L=4πσR2T 4)Envelope (100 m): Huge Temperature Gradient (108K ↔106K )Outer Crust (400 m): Coulomb crystal of exotic neutron-rich nucleiInner Crust (1 km): Coulomb frustrated “Nuclear Pasta”Outer Core (10 km): Neutron-rich uniform matter (n,p,e, µ)Inner Core (?): Exotic matter (Hyperons, condensates, quark matter, . . .)

The Outer Crust: 10−10ρ0 . ρ . 10−3ρ0 (ρ0≈2.4×1014 g/cm3)

Uniform nuclear matter unstable against cluster formationCoulomb Crystal of neutron-rich nuclei immersed in e− Fermi gas

Nuclear Crystallography: Dynamics driven by nuclear massesE/Atot = M(N,Z )/A + 3/4Y

4/3e kFermi + . . .

bcc Crystal of neutron-rich nuclei immersed in a uniform e− gas56Fe, 62Ni =⇒

N=5086Kr, . . . , 78Ni, . . . =⇒

N=82124Mo, . . . , 11836 Kr82(?)

High-precision mass measurements of exotic unstable nuclei essentialISOLTRAP@CERN: The case of 8230Zn52 with a 150 ns half-life!

CERNCOURIERV O L U M E 5 3 N U M B E R 3 A P R I L 2 0 1 3

V O L U M E 5 3 N U M B E R 3 A P R I L 2 0 1 3

CERNCOURIERI N T E R N A T I O N A L J O U R N A L O F H I G H - E N E R G Y P H Y S I C S

ISOLTRAP casts lighton neutron stars

EXPERIMENTSHow CMS ispreparing forthe future p16

COMPUTINGAT THE LHC

Work never stops for the WLCG p21

Kolkata honoursa great Indianphysicist p35

S N BOSE

Welcome to the digital edition of the April 2013 issue of CERN Courier.

Supernova explosions provide a natural laboratory for some interesting nuclear and particle physics, not least when they leave behind neutron stars, the densest known objects in the cosmos. Conversely, experiments in physics laboratories can cast light on the nature of neutron stars, just as the ISOLTRAP collaboration is doing at CERN’s ISOLDE facility, as this month’s cover feature describes. Elsewhere at CERN, the long shutdown of the accelerators has begun and a big effort on maintenance and consolidation has started, not only on the LHC but also at the experiments. At Point 5, work is underway to prepare the CMS detector for the expected improvements to the collider. Meanwhile, the Worldwide LHC Computing Grid continues to provide high-performance computing for the experiments 24 hours a day, while it too undergoes a continual process of improvement. To sign up to the new issue alert, please visit: http://cerncourier.com/cws/sign-up.

To subscribe to the magazine, the e-mail new-issue alert, please visit: http://cerncourier.com/cws/how-to-subscribe.

CERN Courier – digital editionW E L C O M E

WWW.

ED ITOR: CHR IST INE SUTTON, CERNDIG ITAL ED IT ION CREATED BY JESSE KARJALA INEN/ IOP PUBL ISH ING, UK

The Inner Crust: “Coulomb Frustration and Nuclear Pasta”Frustration emerges from a dynamical (or geometrical) competition

Impossibility to simultaneously minimize all elementary interactions

Emergence of a multitude of competing (quasi) ground states

Universal in complex systems (nuclei, e− systems, magnets, proteins,...)

Emergence of fascinating topological shapes “Nuclear Pasta” or “Micro-emulsions"“In 2D-electron systems with Coulomb interactions, a direct transition from a liquid to acrystalline state is forbidden” (Spivak-Kivelson)

How do we taste or smell the nuclear pasta?

Coulomb frustration is a fundamental problem in condensed-matter physicswith widespread implications in nuclear physics and astrophysics!

The Outer/Inner Core: “Heaven and Earth”

Structurally the most important component of the star90% of the size and all of the mass reside in the coreOuter Core: Uniform neutron-rich matter in chemical equilibrium

Neutrons, protons, electrons, and muonsInner Core(?): “QCD made simple (color-flavor locking)”

Hyperons, meson condensates, color superconductors, ???Same pressure creates neutron skin and NStar radiusCorrelation among observables differing by 18 orders of magnitude!

Organizing Committee

Chuck Horowitz (Indiana)

Kees de Jager (JLAB)

Jim Lattimer (Stony Brook)

Witold Nazarewicz (UTK, ORNL)

Jorge Piekarewicz (FSU

Sponsors: Jefferson Lab, JSA

PREX is a fascinating experiment that uses parity

violation to accurately determine the neutron

radius in 208Pb. This has broad applications to

astrophysics, nuclear structure, atomic parity non-

conservation and tests of the standard model. The

conference will begin with introductory lectures

and we encourage new comers to attend.

For more information contact [email protected]

Topics

Parity Violation

Theoretical descriptions of neutron-rich nuclei and

bulk matter

Laboratory measurements of neutron-rich nuclei

and bulk matter

Neutron-rich matter in Compact Stars / Astrophysics

Website: http://conferences.jlab.org/PREX

Conclusions: Neutron Stars as Physics Gold Mines

Astrophysics: What is the minimum mass of a black hole?

Atomic Physics: Pure neutron matter as a unitary Fermi gas

Condensed-Matter Physics: Insights into Coulomb frustration

General Relativity: Neutrons stars as a source of gravitational waves

Nuclear Physics: What is the equation of state of dense matter?

Particle Physics: Quark matter and color superconductors quark matter

It is all connected ...

What is the raw material for making stars and where did it come from?Hydrogen and Helium originated in the Big BangWhat forces of nature contribute to energy generation in stars?All four: Gravitational, Electromagnetic, Strong, and WeakHow and where did the chemical elements form? ?Thermonuclear fusion in the hot stellar interiorHow long do stars live?The lifetime of the star depends exclusively on its massHow will our Sun die?Our Sun will die as a white-dwarf star in about 5 billion yearsHow do massive stars explode? ?Massive stars explode as spectacular SupernovaWhat are the remnants of such stellar explosions?Black holes or neutron starsWhat prevents all stars from dying as black holes?A subtle quantum mechanical effect called Pauli pressureWhat is the minimum mass of a black hole? ?Approximately three times the mass of our Sun