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SEISMIC SEARCH FOR STRANGE QUARK MATTER. V. L. Teplitz January 13, 2005. COLLABORATORS. E. T. Herrin, SMU Seismologist on all papers and, on some papers each: D. C. Rosenbaum, D. Anderson, and I. Tibuleac, SMU J.J. Broderick, Virginia Tech M. Sher, T. Morgan, William & Mary
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SEISMIC SEARCH FOR STRANGE QUARK MATTER V. L. Teplitz January 13, 2005
COLLABORATORS • E. T. Herrin, SMU Seismologist on all papers and, on some papers each: • D. C. Rosenbaum, D. Anderson, and I. Tibuleac, SMU • J.J. Broderick, Virginia Tech • M. Sher, T. Morgan, William & Mary • B. Banerdt, T.C.P. Chui, JPL
Strange Quark Matter (SQM) • Witten (1984): 3 fermi seas; near neutrality • Farhi and Jaffe (1984) MIT Bag: nuclear density, no saturation BE/N increase w. N • N could be 1000+ before binding • M<10^{-9}gm, atom like; m>10{-9}gm lattice like (i.e. electrons mostly inside)
Experiments • de Rujula and Glashow (1984) suggested mica (Price), LDF, seismology, etc • Accelerator production: Sandweiss et al at RHIC (negative; but N could be >1200) • AMS (Ting) • ICE CUBE (Price) • Seismology: below
Nugget Production • Primordial: phase transition; cooling: evaporation v. neutrino energy loss; DM? • NS’s SQS’s; fragments from SQS+SQS • No hint of fragment size/mass distribution in either case • Alcock, Farhi and Olinto SQS structure: glitch issue; Broderick et al radio signal
Intro to Seismology • Point events: 4 variables; line events: 6; distinctive first signal arrival time pattern. • dE/dt=(v³/2)rBpa2 a=(3m/4rN)1/3 • e=seismic/total=0.01 (nuc), 0.02 (chem); >0.5 (quake); SQN? • f=1Hertz (nuc, chem, quake -- SQN?) • Best stations detect approx 0.1erg/cm2-s • Noise: wind, instrument
Monte Carlo • Herrin & VLT (1996): about 50 class 1, many more classes 2 and 3. • Found minimum m, for random geometry, such that 7 or more stations detect. • 97% of detections class 1 • Chances 1/10 of detecting <1 ton nugget; 1/3, 10 ton, and 90% for 220 tons
Real Data • 106 “unassociated” reports 1990-93 (USGS) • Lot of unrecognized quakes • Ignored reports for hour after quake>4.0, non-class 1 stations, signals through core. • Published one likely nugget but learned clock in important station off for month
Anderson et al. Limit • Use 96 MC for p(detection); dN/da=Ka-g; normalize to rDM • g=3.5 Dohnanyi distribution - maintained under collisions • Look for more than one event/year with rSQN=rDM implying must have rSQN<rDM • Find limit for γ~4.0 for all m1, m2 and, for nearby γ, for some (there is γ=4 divergence)
Lunar Seismology • Formation of the moon • Apollo: shallow, deep quakes; impacts • Expect detect 10-3erg/cm2-s, perhaps 10-5. • How well can background noise be separated from instrumental? • Apollo got limits on both number of events and total seismic energy.
Earth-moon Sensitivity Comparison • Cross sections ratio 0.075, but less attenuation to station partially offsets. • More stations on Earth, but placement can be much better on moon • Fewer seismic events on moon but ringing • No ocean or atmosphere on moon implies greatly reduced background - biggest factor • Result: moon 50 or more times more events
Summary • Jury still out on SQM existence • Seismology instrument of choice for high masses • Search of million seismic reports gave negative results and distribution dependent limits • Seismology on moon more sensitive