ZHAireS and neutrino radio detection Washington Rodrigues de Carvalho Jr. Universidade de Santiago de Compostela carvajr@gmail.com GRAND Workshop, LPNHE, Paris February 9th 2015 February 9th 2015 Washington Carvalho (USC) ZHAireS and neutrino radio detection 1 / 36
Overview ZHAireS and ZHAireS-Reflex 1 Emission Mechanisms The ZHAireS code Polarization and the Cherenkov ring Some comparisons with data The Two-component approach approximation ZHAireS-Reflex Radio array sensitivity to Earth-Skimming ν τ 2 End to end simulation Efficiency and Exposure Sensitivity of a radio array February 9th 2015 Washington Carvalho (USC) ZHAireS and neutrino radio detection 2 / 36
ZHAireS and ZHAireS-Reflex Emission Mechanisms Emission mechanisms Two main emission mechanisms: Geomagnetic emission mechanism Askaryan or charge excess emission mechanism Moving charged particles radiate Movement can be described in terms of a current � J ( t ) From Lienard-Wiechert potentials (disregarding static term): E ∝ ∂� ∂ t ∝ ∂� � A J ⊥ ^ ∂ t , where n � n × � J J ⊥ = − ˆ n × (ˆ J ) and J Antenna n is the observation direction ˆ February 9th 2015 Washington Carvalho (USC) ZHAireS and neutrino radio detection 3 / 36
ZHAireS and ZHAireS-Reflex Emission Mechanisms Askaryan Mechanism Dominates emission in dense media Electron and positron currents are opposite e - J + e + J - v v v approx. paralell to shower axis � J + + J - = 0 Emission is due to an excess of electrons in the shower Shower front entrains electrons from medium ( Compton , Møller, Bhabba and positron anihilation) G.A. Askaryan, Soviet JETP 21 (1965) 658 February 9th 2015 Washington Carvalho (USC) ZHAireS and neutrino radio detection 4 / 36
ZHAireS and ZHAireS-Reflex Emission Mechanisms Geomagnetic mechanism Dominates emission in atmospheric showers Charged particles deflected by geomagnetic field � B Emission from electrons and positrons add up B J - J + v - v + J F.D. Kahn and I. Lerche, Procs. Royal Society A 289 (1966) 206 February 9th 2015 Washington Carvalho (USC) ZHAireS and neutrino radio detection 5 / 36
ZHAireS and ZHAireS-Reflex The ZHAireS code The ZHAireS code ZHAireS (ZHS + Aires): Simulation of radio emission in air showers and dense media (ice) Full shower simulation using Aires Radio emission calculation based on ZHS algorithms First microscopic simulation with refractive index n > 1 and varying n ( h ) Can easily simulate emission of neutrino induced showers (special primary) AstropaPhys, 35 , 325, 2012 and AstropaPhys, 35 , 287, 2012 ZHS algorithms: First principles (Maxwell) - No emission model presupposed. Geomagnetic, Charge Excess (Askaryan), etc... all included Frequency- and Time-domain calculations of vector potential � A and electric field � E Zas, Halzen, Stanev, Phys.Rev.D V 45 , 362 (1992) and Phys.Rev.D81:123009,2010 February 9th 2015 Washington Carvalho (USC) ZHAireS and neutrino radio detection 6 / 36
ZHAireS and ZHAireS-Reflex The ZHAireS code Extended ZHS algorithms: Time and Frequency domains Time domain 6 Θ( t − t det ) − Θ( t − t det ) 5 � 4 π Rc � µ e � C A ( t , ˆ u ) = β ⊥ 1 2 A ( x ,t ) (arb. units) � ✟ 4 1 − n � β · ˆ u 3 � > 2 � C � < � C ✄ ec ☎ sin 1 ✆ Frequency domain 4 ✝ (1 ✞ n ☎ cos ✆ ) 0 β ⊥ e i ω ( t − tdet ) − e i ω ( t − tdet -1 (1 ✁ n ✂ cos � )( t 2 ✁ t 1 ) ) � u ) = − µ e 2 π c � 1 2 E ( ω, ˆ -2 -4 -3 -2 -1 0 1 2 3 4 5 1 − n � β · ˆ u 6 � C � ✟ E = ✁ d A /dt E ( x ,t ) (arb. units) 4 � > 2 � < � C � C t 1 , E 1 , x 1 0 -2 -4 -6 -4 -3 -2 -1 0 1 2 3 4 5 û (const) t ✁ nR/c (arb. units) v R (const) θ Santiago group, t 2 , E 2 , x 2 Phys.Rev.D 81 ,123009 (2010) February 9th 2015 Washington Carvalho (USC) ZHAireS and neutrino radio detection 7 / 36
ZHAireS and ZHAireS-Reflex Polarization and the Cherenkov ring Polarization Geomagnetic mechanism polarization ( � G ) Aproximatelly paralell to − � V × � B Independant of observer position Askaryan mechanism polarization ( � A ) Aproximatelly radial w.r.t. shower axis � V Depends on observer position B G α ( parallel to -V x B) A θ (radial to V) V February 9th 2015 Washington Carvalho (USC) ZHAireS and neutrino radio detection 8 / 36
ZHAireS and ZHAireS-Reflex Polarization and the Cherenkov ring Superposition of emission mechanisms: Asymmetries Vertical shower with horizontal � B geo-magnetic N Askaryan W E S February 9th 2015 Washington Carvalho (USC) ZHAireS and neutrino radio detection 9 / 36
ZHAireS and ZHAireS-Reflex Polarization and the Cherenkov ring Superposition of emission mechanisms: Asymmetries Vertical shower with horizontal � B geo-magnetic N Askaryan W E S February 9th 2015 Washington Carvalho (USC) ZHAireS and neutrino radio detection 9 / 36
ZHAireS and ZHAireS-Reflex Polarization and the Cherenkov ring Superposition of emission mechanisms: Asymmetries Vertical shower with horizontal � B North of core EW component: pure geomagnetic NS component: pure Askaryan geo-magnetic N Askaryan W E S South of core EW component: pure geomagnetic NS component: pure Askaryan February 9th 2015 Washington Carvalho (USC) ZHAireS and neutrino radio detection 9 / 36
ZHAireS and ZHAireS-Reflex Polarization and the Cherenkov ring Superposition of emission mechanisms: Asymmetries Vertical shower with horizontal � B North of core EW component: pure geomagnetic NS component: pure Askaryan geo-magnetic N Askaryan West of core Askaryan and geomagnetic have opposite directions: W E They subtract S South of core EW component: pure geomagnetic NS component: pure Askaryan February 9th 2015 Washington Carvalho (USC) ZHAireS and neutrino radio detection 9 / 36
ZHAireS and ZHAireS-Reflex Polarization and the Cherenkov ring Superposition of emission mechanisms: Asymmetries Vertical shower with horizontal � B North of core EW component: pure geomagnetic NS component: pure Askaryan geo-magnetic N Askaryan West of core East of core Askaryan and Askaryan and geomagnetic have geomagnetic are opposite directions: W E parallel: They add up They subtract S South of core EW component: pure geomagnetic NS component: pure Askaryan February 9th 2015 Washington Carvalho (USC) ZHAireS and neutrino radio detection 9 / 36
ZHAireS and ZHAireS-Reflex Polarization and the Cherenkov ring Superposition of emission mechanisms: Asymmetries Vertical shower with horizontal � B North of core EW component: pure geomagnetic NS component: pure Askaryan geo-magnetic N Askaryan Net field West of core East of core E=E(r, φ ) Askaryan and Askaryan and geomagnetic have geomagnetic are opposite directions: W E parallel: They add up They subtract S South of core EW component: pure geomagnetic NS component: pure Askaryan February 9th 2015 Washington Carvalho (USC) ZHAireS and neutrino radio detection 9 / 36
ZHAireS and ZHAireS-Reflex Polarization and the Cherenkov ring Superposition of emission mechanisms: Asymmetries geo-magnetic N Askaryan Net field E=E(r, φ ) W E EW component NS component S Astropar. Phys., 35 , (2012) 325 February 9th 2015 Washington Carvalho (USC) ZHAireS and neutrino radio detection 10 / 36
ZHAireS and ZHAireS-Reflex Polarization and the Cherenkov ring Cherenkov Ring Observers that see X max at θ C ~Xmax Shower Axis E Define a ring-like region on the ground Out Maximum field amplitude N S In Out Out Sizeable intensity well into the GHz range Out Ring is elliptical for non-vertical showers W 70 ◦ shower Cherenkov -4 100 m in -3 300 MHz 10 10 × 0.14 100 m out EW Line 200 m in 200 m out 0.12 NS Line 400 m in 400 m out 0.10 (V/m/MHz) E (V/m/MHz) -5 10 0.08 EW 0.06 E 0.04 -6 10 0.02 200 400 600 800 1000 1200 1400 0.00 -1500 -1000 -500 0 500 1000 1500 Frequency (MHz) Coordinate (m) J. Alvarez-Mu˜ niz, W. Carvalho Jr., A. Romero-Wolf, M. Tueros, E. Zas, Phys. Rev. D 86 (2012) 123007 February 9th 2015 Washington Carvalho (USC) ZHAireS and neutrino radio detection 11 / 36
ZHAireS and ZHAireS-Reflex Some comparisons with data ZHAireS simulations in good agreement with data ZHAireS simulation of AERA event V / m] 2000 ZHAireS, SIBYLL 2.1 Measurement µ | [ Proton E | Iron 1500 1000 500 0 100 200 300 400 500 600 700 distance to shower axis [m] Pierre Auger Collaboration, ICRC2013, id #899 February 9th 2015 Washington Carvalho (USC) ZHAireS and neutrino radio detection 12 / 36
ZHAireS and ZHAireS-Reflex Some comparisons with data Very good agreement of the RLDF shape LOFAR X max reconstruction using ZHAireS simulations ( σ X max ∼ 20g / cm 2 ) February 9th 2015 Washington Carvalho (USC) ZHAireS and neutrino radio detection 13 / 36
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