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SHENIE : S imulation of H igh E nergy N eutrino I nteracting with the E arth. M.A. Huang a , Y.L. Hong b , C.H. Iong bc , G.L. Lin b (a) General Education Center, National United University, 1, Lien-da, Kung-ching Li, Miao-Li, 36003, TAIWAN
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SHENIE: Simulation of High Energy Neutrino Interacting with the Earth M.A. Huanga, Y.L. Hongb, C.H. Iongbc, G.L. Linb (a) General Education Center, National United University, 1, Lien-da, Kung-ching Li, Miao-Li, 36003, TAIWAN (b) Institute of Physics, National Chiao-Tung University, 1001 Ta Hsueh Rd., Hsin-chu, 300, TAIWAN (c) Current Address: Institute of Physics, Academia Sinica, Nankang, Taipei, 105, TAIWAN Presenter: M.A. Huang (mahuang@nuu.edu.tw), M.A. Huang
What is SHENIE SHENIE means goddess in Mandarin! M.A. Huang
UHE- fluxes • So many UHE- fluxes, how to detect them? • Traditional detector technology • NuTel & CRTNT • New techniques • Radio • Sound wave Need MC simulation for neutrino interacting with the Earth! M.A. Huang
Mauna Loa NuTel View from Hualalai Target: Mauna Loa, Hawaii Big Island, USA http://hep1.phys.ntu.edu.tw/nutel/ P. Yeh, et al., Modern Physics Lett. A.19, 1117-1124, (2004). See NuTel talk by Bob Y. Hsiung M.A. Huang
CRTNT • Target: Mt. Wheeler, Nevada, USA. • (prototype in construction) • Z. Cao, M.A. Huang, P. Sokolsky, Y. Hu, J. Phys. G,31, 571-582, (2005) Highlight of the year 2005 by J PG See CRTNT talk by Zhen Cao M.A. Huang
1 Antenna array 2 3 Depth (km) 4 • Halite (rock salt) • La(<1GHz) > 500 m w.e. • Depth to >10km • Diameter: 3-8 km • Veff ~ 100-200 km3 w.e. • No known background • >2p steradians possible 5 6 7 Radio array in salt dome • Radio signal from EAS • Large Cherenkov angle! • Underground salt dome. • Higher density than water/ice • Good transparency to radio signal • Free of artificial noise Figure comes from Peter Gorham, talk in SLAC SalSA workshop, 2005. M.A. Huang
Previous version of SHENIE • Monte-Carlo simulation for all processes except energy loss, which use deterministic method. • where decay length = E. • Publications based on this version: • M.A. Huang, J.J. Tseng, and G.L. Lin (7/31- 8/7, 2003) Proc. of the 28th ICRC, Tsukuba, Japan, p.1427, (2003) • M.A. Huang, Proc. of the 21th International Conference on Neutrino Physics and Astrophysics (ν-2004) at Paris, French, Nucl. Phys. B (Proc. Suppl.), 143, 546, (2005); astro-ph/0412642 • P. Yeh, et al., Proc. of CosPA 2003, Modern Physics Lett. A.19, 1117-1124, (2004) • Z. Cao, M.A. Huang, P. Sokolsky, Y. Hu, J. Phys. G, 31, 571-582, (2005) M.A. Huang
Direction, position New event E CC : e E Propagation thru. Earth Tauola decay dE/dx Enter DSR N Y h CC/NC leptons E dE/dx N Exit DSR N Y Y e Enter DSR Esh shower hadrons Y N Current SHENIE structure M.A. Huang
Global : Isotropic distribution of & path length L and total depth Local : User supplied topological map Altitude (East, North) X: geometric East Y: geometric North Z: Vertical (geodetic) outward L R L=2Rsin Coordinate system M.A. Huang
Earth Model • Spherical Earth, R = 6371.2 Km • Density/composition profile • Material around detector can be selected from 4 materials. M.A. Huang
1 km Salt dome Std. rock 5 km DSR • DSR: Detector Sensitive Region • For SalSA simulation: Sphere of 5 km radius, under 1km of rock. • For ES telescope: DSR set on top of Earth and local topological map must be supplied. M.A. Huang
-N interaction • CC/NC total cross-section determine interaction probability. • W–resonance can be added by users • Non-Standard model cross-section can be implemented as external data file • G.L. Lin, M.A. Huang, C.H. Iong, work in progress M.A. Huang
Materials • 4 materials: std. rock, water (ice), salt, iron • Input particles: • e/e , / , / • Energy loss of and in 4 materials • Ionization (). • Pair Production, Photo-Nuclear, Bressmstrlung • Soft energy loss cut at 0.01 (can be changed) • Tau loss by ~ 0.16% at E > 2.51017 eV. M.A. Huang
decay • decaysimulated by • Randomly choose one event from a data bank of pre-simulated events • current version • Link to TAUOLA • in near future • TAUOLA simulation • Fully polarized • Tauola have 22 decay modes, while PDB have 37 modes • TAUOLA gives 4 momentum in CM of all decay particles • Define E’cm = P║ + M • Boost to lab by = E-lab / M • Secondary particle energy in lab frame E’lab = E’cm M.A. Huang
Shower energy • If decay inside Earth, E-lab is calculated and are re-propagated thru the rest of journey. • If decay in atmosphere, shower energy Esh is sum over Elabof hadrons or electron / gamma. • The mean energy per particles is calculated by Esh/M, where M is number of secondary particles which generate shower. Mean energy ~ 0.5 M.A. Huang Esh-CM
Consistence check • Use several methods to calculate tau flux passing through 100km of standard rock for two different source spectrum (AGN and GZK). • MC: Use SHENIE, this work • M.A. Huang, et al., paper in preparation. • Semi-MC: MC in all processes except dE/dX • M.A. Huang, Proc. of ν-2004 at Paris, Nucl. Phys. B, 143, 546, (2005) • Analytical calculation: Solve and transport eq. • J.J. Tseng et al., Phys. Rev. D 68, 063003, (2003). • Source spectrum: • AGN: A. Neronov, et al., Phys. Rev. Lett., 89, 051101 (2002) • GZK: R. Engel, D. Seckel and T. Stanev, Phys. Rev. D 64, 093010 (2001). Typical Earth skimming event, =90.5, cord length ~100 km. M.A. Huang
AGN fluxes • MC method produce results similar to analytical method. • Conditions used in MC: • 105 GeV < E < 1010 GeV • N=3107 • ~1.10 1020 cm-2 s-1 sr-1 • N=2979 (at E > 105 GeV) • Mean conversion efficiency 9.9310-5 • Total fluxes 2.710-17 (cm2 sr s)-1 ; Equivalent to 8.5 events/(km2 sr yr) • Should multiply trigger efficiency and acceptance to get event rate. • Both energy-dependent energy peak at around 5~63 PeV, shower energy will peak around 10 PeV. M.A. Huang
GZK fluxes • For GZK neutrinos, • Slightly move to lower energy due to large energy loss. • MC simulation conditions: • 105 GeV < E < 1012 GeV • N=508294 • ~1.521022 cm-2 s-1 sr-1 • N=5969 (at E > 105 GeV) • Mean conversion efficiency 1.1710-2 • Total fluxes 3.910-19 (cm2 sr s)-1 ; Equivalent to 0.12 events/(km2 sr yr) • energy peak at around 0.04 PeV ~1.6 EeV, Shower energy will peak around 0.1 EeV. M.A. Huang
Underground salt dome detector • Strawman array: 12 x 12 strings, 12 nodes per string (8 shown), 225 m spacing. • Total volume (2.475km)3 = 15.16 km3 = 32.83 km3 of w.e. • Figure and specification come from Peter Gorham, talk in SLAC SalSA workshop, Mar. 2005. M.A. Huang
Results -1 • cos vs. shower energy: all events M.A. Huang
SalSA tau events • Showers come from several processes: decay, energy loss, CC and reverse CC. • For each event, the maximum energy of sub-showers were used to identify this event. M.A. Huang
(Eth=1015 eV) • FWHM of cos distribution: -0.05 < cos < 1, i.e. 0< < 93 • FWHM of Esh: 1016.5 eV < Esh < 1018 eV. M.A. Huang
Conclusion • SHENIE simulation code is “almost” finish! • Still need some cosmetic works on user friendly I/O. • Especially, need to work on output to ntuple. • No manual or any documentation yet! • For Earth skimming events: • AGN tau flux ~ 8.5 events/(km2 sr yr), need detector ~ 1 km2 sr • Shower spectrum peak around 1016 eV. • GZK tau flux ~ 0.12 events/(km2 sr yr), need detector ~ 100 km2 sr • Shower spectrum peak around 1017 eV. • For underground detector such as SalSA: • Shower spectrum peak around 1017 eV. • -0.1 < cos <1. • In a radius of 5km salt dome, tau event rate could reach ~ 2.5 events/year • Highly depend on detector simulation, which is highly simplified in this study. M.A. Huang