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The nature of compressed baryonic matter. Renxin Xu ( 徐仁新 ) School of Physics, Peking University ( ) Pulsar searching and timing with FAST “ PKU Astrophysics Colloquium 2012 ” Oct. 21, 2012; Biejing. Compressed baryonic matter http :// vega.bac.pku.edu.cn/ rxxu R . X. Xu. Summary.
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The nature of compressed baryonic matter RenxinXu (徐仁新) School of Physics, Peking University () Pulsar searching and timing with FAST “PKU Astrophysics Colloquium 2012” Oct. 21, 2012; Biejing Compressed baryonic matterhttp://vega.bac.pku.edu.cn/rxxu R. X. Xu
Summary • Introduction: what’s compressed BM? • EoS of compressed BM: specu. & obs. • To understand EoS by large telescope • Conclusions Compressed baryonic matterhttp://vega.bac.pku.edu.cn/rxxu R. X. Xu
Introduction: what’s compressed BM? • What is baryon: the standard model of particle physics • 48 Baryon (a quark) = 1/3 • 1 Higgs Boson 13 Totally: 62 Compressed baryonic matterhttp://vega.bac.pku.edu.cn/rxxu R. X. Xu
The particle has been the subject of a 45-year hunt to explain how matter attains its mass. 5!
Introduction: what’s compressed BM? . {uud} {udd} . . . ~100 cm ~10-8 cm ~10-13 cm • A brief history about compressed baryonic matter … • G. Gamow (~1930): incompressible liquiddrop for atomic nuclei • L. Landau (1932, before n): what if drops are concentrated by gravity? • Landau’s idea of “gigantic nucleus” develops to normal NS model... • What if the quark degree of freedom (and w & s int.) is not negligible? • our answer: {u, d, s}, > 6 (rather than 3) grouped in a cluster in CBM. Compressed baryonic matterhttp://vega.bac.pku.edu.cn/rxxu R. X. Xu
Introduction: what’s compressed BM? All of the world's population A rubber made of NM/SM Compressed baryonic matterhttp://vega.bac.pku.edu.cn/rxxu R. X. Xu
Summary • Introduction: what’s compressed BM? • EoS of compressed BM: specu. & obs. • To understand EoS by large telescope • Conclusions Compressed baryonic matterhttp://vega.bac.pku.edu.cn/rxxu R. X. Xu
EoS of compressed BM: specu. & obs. • EoS of compressed BM: the mainstream … Alford (2004) Compressed baryonic matterhttp://vega.bac.pku.edu.cn/rxxu R. X. Xu
EoS of compressed BM: specu. & obs. Xu 2009, JPG, 36, 064010 coupling between quarks? … DSE approach of NQCD ? Clustering ← BEC ← BCS A quark clustering phase? Compressed baryonic matterhttp://vega.bac.pku.edu.cn/rxxu R. X. Xu
EoS of compressed BM: specu. & obs. • Differences between NS & quark-cluster star? ~ (1, 10) km conventional neutron star quark-cluster star (Heiselberg, 2000) (Xu, 2011) • Gravity-bound (weak binding) vs. Self-bound (strong) • Atmosphere vs. {q-clusters, electron sea}
EoS of compressed BM: specu. & obs. • A quark-cluster star looks like a big metal ball Metal ballV.S. Quark-cluster star ions/nuclei quark clusters E-M interaction strong/color one Compressed baryonic matterhttp://vega.bac.pku.edu.cn/rxxu R. X. Xu
EoS of compressed BM: specu. & obs. • A realistic quark cluster: H-dibaryon? H-particles in lattice QCD: Beane et al. [NPLQCD Collaboration], Phys. Rev. Lett. 106, 162001 (2011) Inoue et al. [HAL QCD Collaboration], Phys. Rev. Lett. 106, 162002 (2011) What if quarks are clustered as H-diabaryons in QS? Lai, Gao & Xu (arXiv:1107.0834) Interaction between H’s is mediated by - mesons: In-medium stiffening effect: Brown-Rho scaling modified. Compressed baryonic matterhttp://vega.bac.pku.edu.cn/rxxu R. X. Xu
EoS of compressed BM: specu. & obs. • A realistic quark cluster: H-star? Mmax-V0 M-R, M-c Compressed baryonic matterhttp://vega.bac.pku.edu.cn/rxxu R. X. Xu
EoS of compressed BM: specu. & obs. • A corresponding-state approach to … Wilczek (2007) • The results (Guo, Lai & Xu; arXiv1209.3688): • Dimensionless parameters: • Corresponding state law EoS Compressed baryonic matterhttp://vega.bac.pku.edu.cn/rxxu R. X. Xu
Summary • Introduction: what’s compressed BM? • EoS of compressed BM: specu. & obs. • To understand EoS by large telescope • Conclusions Compressed baryonic matterhttp://vega.bac.pku.edu.cn/rxxu R. X. Xu
To understand EoS by large telescope • Key observables of radio pulsars 1, Timing (ToA): spin-behavior + space-time fluctuations + post-Newtonian orbital effects + binary parameter + ISM +planetary ephemeris+time standards/navigation? 2, Pulse profile: radiative process (magnetospheric activity)+ ISM Large radio FASTtelescopes are certainly necessary to measure precisely these two. Compressed baryonic matterhttp://vega.bac.pku.edu.cn/rxxu R. X. Xu
To understand EoS by large telescope • To know compressed BM by large telescope • To measure the mass of radio pulsars • To measure the inertial of momentum of NS • To find sub-ms radio pulsars • … Compressed baryonic matterhttp://vega.bac.pku.edu.cn/rxxu R. X. Xu
To understand EoS by large telescope Lai & Xu (2009, Nq = 18, U0 = 100 MeV) PSR J1614 Demorest et al. (2010) (Sala et al. ApJ, arXiv:1204.3627) (Lai & Xu 2009 MNRAS, 398, L31)
Summary • Introduction: what’s compressed BM? • EoS of compressed BM: specu. & obs. • To understand EoS by large telescope • Conclusions Compressed baryonic matterhttp://vega.bac.pku.edu.cn/rxxu R. X. Xu
Conclusions • Pulsars are not only extreme labs of gravity, but also of the fundamental strong interaction. • As manifestation of compressed baryonic matter, pulsars are sending us message being essential for us to know non-perturbative QCD. • We are suggesting: realistic compressed baryonic matter at a few nuclear densities is composed by quark-cluster matter. Thanks!