Exotic Phases of Matter in Compact Stars Disk Galaxy NGC 4526 in Virgo Supernova 1994D Fredrik Sandin [email protected] Outline • Introduction • Colour superconducting quark matter in “neutron stars” • Preon stars, a new class of compact stars in the cosmos? 2/ 16 Stars • Form in clouds of interstellar gas •Gravity Æ Pressure + heat Æ Fusion Æ Thermal pressure Æ Equilibrium “Pressure = Gravity” • Fusion Æ Heavy elements Æ Less “fuel” Æ ... Æ COLLAPSE 3/ 16 Compact Stars • The corpses of stars • Form when some stars collapse • Gravitational energy Æ Gigantic explosion (supernova) • Three main types: Puppis A • White dwarfs ρ ∼ 107 g/cm3 • Neutron stars ρ ∼ 1015 g/cm3 • Black holes ρ ~ M/R3 ROSAT X-ray Observatory 4/ 16 The Composition of “Neutron Stars” F. Weber, Prog. Part. Nucl. Phys. 54 (2005) p. 193 … is unknown 5/ 16 Conjectured Phase Diagram of Strongly Interacting Matter Early Universe LHC (CERN) Quark-Gluon Plasma (QGP) RHIC (BNL) SPS (CERN) AGS (BNL) Supernovae SIS (GSI) Colour Superconductor Temperature (T) Hadron Gas Vacuum (<qq>) Nuclear Matter “Neutron Stars” µ Baryon chemical potential ( B) 6/ 16 Model of Quark Matter µ • Three flavours ( B/3 > Ms) • Quark masses generated dynamically • Attractive q-q interaction (colour 3 channel) 7/ 16 Model of Quark Matter (2) • Other important issues • Weak interactions (leptons included) • No gluon fields Æ No gluon condensates, 0 , 〈A a〉 that neutralize colour charges Æ Colour neutrality must be enforced • The parameters are fixed with experimental results, e.g., meson properties • Mean-field (Hartree) approximation + Imaginary-time formalism Æ Thermodynamic potential Æ 8/ 16 Phase Diagrams Ex. 9/ 16 Quark/Hybrid Star Properties Ex. Mass-Radius Relations Ex. Cooling Evolution 10 / 16 Desert of 11 / 16 instability Preon Stars • Preons • Hypothetical building blocks of quarks, leptons and (some) gauge bosons Molecule Atom Nucleus Proton Quark Preon 3000 BC 1811 1905 Time (Adam & Eve) 1911 1968 2007? • Some estimates indicate that preons, e.g., in massive quarks, are in-reach of the next generation of particle accelerators. Though, maybe not… • If preons exist, preon stars could exist J. Hansson & F. Sandin, Phys. Lett. B 616 (2005), pp. 1-7. F. Sandin, Eur. Phys. J. C 40 (2005), pp. 15-22. 12 / 16 13 / 16 Mass and Radius of Preon Stars • Can be estimated with several methods, e.g., • Chandrasekhar limit • Schwarzschild radius • In general: Jahre Viking 2 • M < ~10 MEarth • R < ~101 m 485 m 8 6.5 x 10 kg 14 / 16 J. Hansson & F. Sandin, to be submitted Observation 15 / 16 GRB Distance ~ 1010 light years 17 kg Preon Star 24 kg 14 < M < ~10 14 < M < ~10 Observable range: • One satellite: ~10 • Two satellites: ~10 Work in Progress • Quark Matter 1. Constraint for gapless excitations 2. Influence of non-local form factors 3. Influence of hadronic crust (hybrid stars) •PreonStars 4. Interpretation of absorption lines found in some GRB spectra 5. High-frequency gravitational waves from binaries (ÆR?) 16 / 16.