Astro-Particle Physics with Nuclear Track Detectors Eduardo Medinaceli V. INFN, Sez. Bologna, Italy 1.Nuclear Track Detectors (NTD) 2.SLIM experiment (research of “exotic” particles) 3.CAKE experiment (primary cosmic ray composition) High Energy Physics in the LHC era 3° International Workshop Valparaiso - Chile

Astro-particle Physics p + nuclei rad. γ Magnetici Monopoles Strange Quark Matter ? Sun UHE  SN ? WIMPs Introduction ?

Symmetry of Maxwell Equations (cgs units) 1931 Dirac: Quantization of electric charge Proc. R. Soc. London, 133 ( 1931) 60 Dirac relation 2/15 Magnetic Monopoles

Intermediate Mass Magnetic Monopoles (IMM) Introduction SO(10) GeV s SU(4) x SU(2) L x SU(2) R 10 9 GeV s SU(3) C x [SU(2) L x U(1) Y ] EW + … 10 5 ≤ M ≤ GeV β = n g D B β > 0.03 Virtual vector bosons X, Y? Electroweak Unification W, Z Virtual photons and gluons Confinement region Magnetic field of a point MM Radius (m) IMM Energy Losses  β > Ionization (à la Bethe-Bloch) (Ze eq ) 2 = (gβ) <β<10 -3 Drell effect M + He  M + He* Penning effect He*+ CH 4  He + CH 4 + e -  β < Elastic collisions De Rujula CERN-TH 7273/94, E. Huguet & P. Peter hep-ph/ , T.Kephart, Q. Shafi Phys. Lett. B520(2001)313, Wick et al. Astropart. Phys. 18, 663 (2003)

Strange Quark Matter (SQM) Introduction - aggregates of u, d, s ( ~ same number) + electrons - stable for barionic numbers  some hundreds < A < u.m.a. - density ρ SQM  3.5 x g cm -3 ( ρ nuclei  g cm -3 ) - ratio Z/A low De Rujula, Nucl. Phys. A434, 605 (1985)

Nuclear Track Detectors (NTD) CR39® ρ = 1.32 g /cm 3 (C 12 H 18 O 7 ) n MAKROFOL ® ρ = 1.29 g /cm 3 (C 16 H 14 O 3 ) n NTDs 158 A GeV 82+ Pb in CR39 20X Mag. 150X150 μm 2 Reduced etch rate: p = v T /v B Latent Track 100X70 μm 2 Chemical Etch KOH, NaOH in different concentrations

Calibrations In 49+ & Pb A GeV CERN–SPS, Pb target Fe 26+ & Si and 5 A GeV BNL–AGS, CH 2 target 0.41 A GeV Fe 26+ and 0.29 A GeV C 6+ HIMAC detector typeZ/β REL [MeVcm 2 /g] v B [ μm/h] CR ±0.4 strongCR39DOP ±0.3 Makrofol ±0.1 softCR ± 0.02 CR39DOP ± 0.02 p-1 Survived beam Fragments Target Incident ion beam NTD Z/  = 78 Z/  = 82 Z/  = Z/  = Z/  = 46 Z/  = 49 CR39 Makrofol for β > 0.01

SLIM Acceptance -dE/dx Strangelets IMM

The SLIM experiment(Search for Light Magnetic Monopoles) SLIM res atm= 540 g/cm 2 R = 12.5 GV area = 427 m 2 t = 4.22 years 24 X 24 cm stacks 10 5 ≤ M IMM ≤ GeV   > ≤ M SQM ≤ GeV  > 0.001

negative positive neutral C 12 H 18 O 7 (ρ = 1.31 g/cm 3 ) dim = 1450 μm x 1 x 1 cm 2 Φ N ~ 1.8x cm -2 s keV – 20 MeV Zanini et Statistical studies of n indiced background in CR39 SLIM

Area = 427 m 2, t = 4.22 years Φ ≤ 1.3x cm -2 sr -1 s -1, β>0.03 for IMM β>10 -4 for Strangeletes and Nuclearites SLIM results 90% C.L. IMM SQM Rad. Meas. 44 (2009) 889–893 arXiv: [hep-ex]

Si Li-Be-B Sc-Ti-V-Cr C Fe N O Chemical composition of Cosmic Rays Composition of RC

First Ionization Potential (FIP) (~ measurement of the bounding force of an e) Volatility/Refractory (prop. to remain in the gas/solid phase T cond ) Injection Mechanisms ~10 4 °K Composition of CR FIP Vol/Ref 31 Ga, 32 Ge 79 Au Big exposure area Long balloon flight / ISS Requirements

The CAKE experiment (ASI) CAKE - ASI Cosmic Abundances below the Knee Energy prototipe for ULDB h ~ 40 km, residual Atm ~ 3.5 g/cm 2, t ~ 20 h geomagnetic cut-off >9GV (E > 3 GeV/n) Non stabilized “gondolla” CR39 ® CR39 ® Z th > 5 (0.7 mm -1.4 mm) Makrofol Makrofol Z th > 55 (0.25 mm) A = 1 m 2 80 stacks (11.5 X 11.5 cm 2 ) stack mean thickness 2.5 g/cm 2

Automatic measurements valid track candidates background tracks ELBEK - SAMAICA deffectsEOR Low charge TOP BOTTOM

Classification “Signal/background”- FILTERING CAKE Neural Network semi automatic measurement

Tracking

CAKE results 3.5g/cm 2 per 14h 15m 66 (stacks) x 0,072 m 2 ≈ 0.5 m 2 ~ 6000 measured events (passing through 3 layers) Total number of eventsRelative Abundances at the top of the atm CAKE arXiv: v1[astro-ph]

NTD were used by the SLIM experiment in the search of massive particles in the cosmic radiation, obtaining the best upper flux limits for IMM and SQM. NTD were used successfully by the CAKE experiment in the measurement of the abundances of nuclei with 10 ≤ Z ≤ 31, showing good agreement with other experimental data. NTD are cheap and easy to handle detectors that offers good charge resolution and variable charge thresholds. Summary

BACKUP SLIDES

Monopoli Magnetici SO(10) GeV s SU(4) x SU(2) L x SU(2 ) R 10 9 GeV s SU(3) C x [SU(2) L x U(1) Y ] EW + … GUT MM GeV IMM GeV SLIM MACRO Φ < 1.4* cm -2 sr -1 s -1 Dirac 1931: eg = n ħc/2 per n=1 g d = ħc/2e = 68.5e SU(5) SU(3) C x [SU(2) L x U(1) Y ] EW SU(3) C x U(1) EM 10 2 GeV s s GeV Kephard, Shafi. ( M ~ GeV g=2*g d ) Q. Shafi et al. Glashow et. al

Stati coerenti di squarks, sleptons, campi di Higgs + e, ē 10 8 < M Q < GeV, < β < generati nell’universo primordiali candidati di cold dark matter   R Q : dimensioni del Q-ball core; i punti neri indicano elettroni, i cerchi aperti indicano s-electrons. Carichi, SECS Neutri, SENS Q-balls supersimmetrici

CR39® ρ = 1.32 g /cm 3 (C 12 H 18 O 7 ) n A/Z = MAKROFOL ® ρ = 1.29 g /cm 3 (C 16 H 14 O 3 ) n A/Z = A GeV 82+ Pb in CR39 20X Mag. 150X150 μm 2 Chemical etching solutions CR39® 0.1% dioctyl phthalate DOP ρ = 1.32 g /cm 3 (C 12 H 18 O 7 ) n 150X150 μm 2 SLIM Nuclear Track Detectors (NTD) detector typesolution CR398N KOH + 1.5% alcohol 70° C 30h strongCR39 DOP8N KOH + 1.5% alcohol 75° C 30h Makrofol6N KOH + 20% alcohol 75° C 30h softCR396N NaOH + 1% alcohol 70° C 40h CR39 DOP 6N NaOH 70° C 40h The alcohol added in the etching solution improved the detector surface quality

Numero totale di eventi

First Ionization Potential (FIP) (~ misura la forza di legame di un e) Volatility/Refractory (prop. di rimanere nella fase gassosa/condesata T cond ) Meccanismi d’accelerazione ~10 4 °K Composizione RC FIP Vol/Ref 31 Ga, 32 Ge 79 Au

L’angolo limite di rivelazione nei NTDs NTDs

L5 scan Mag: 200 – 400X L1 scan Mag: 0.8X obj – 10X eye piece Scan SLIM

Composizione RC

SLIM Acceptance -dE/dx Strangelets IMM

Background identification REL TOP = 455 MeVg -1 cm -2 REL BOTTOM = 749 MeVg -1 cm -2 CARBON RECOIL SLIM soft etching strong etching