Summary of MACRO results on exotic physics

1. EPNT 2006 Summary of MACRO results on exotic physics Workshop on Exotic Physics with Neutrino Telescopes Uppsala, Sweden, September 20-22, 2006 M. Giorgini (Bologna University and INFN) MACRO Coll. : Bari, Bologna, Boston, Caltech, Drexel, Frascati, Gran Sasso, Indiana, L’Aquila, Lecce, Michigan, Napoli, Pisa, Roma, Texas, Torino, Oujda.

2. 1984 : Proposal 1987 : Construction starts The MACRO experiment 1989 : First Supermodule ON 4/1994 : Full detector ON 12/2000 : Rest In Peace

3. nm-induced muon events in MACRO • Average rock overburden : 3700 hg/cm2 • Reduction factor of downgoing m : ~ 106 • Total acceptance : ~ 10000 m2 sr for an isotropic flux • Limited streamer tubes • (ang. res. < 1°) • Liquid scintillation counters • (time res. ~ 500 ps) • Nuclear track detectors

4. MCno osc MCno osc MCosc MCosc q IU m Zenith distributions Upthroughgoing m ID + UGS m

5. MC predictions for nm nt oscillations with the best MACRO parameters L/En distribution From the shape of the muon zenith distribution From the measurement of the muon energy using their Multiple Coulomb Scattering [Phys. Lett. B566 (2003) 35] Upthr. m data( ~300 events) IU m data 12% point-to-point syst. error

6. Matter effects : OSCILLATION HYPOTHESIS Minimum value for nm nt : Rtmin =1.61 Minimum value for nmnsterile : Rstmin =2.03 PROBABILITY FOR R < Rmin : Pt= 7.2% ; Psterile = 0.015% Pt/Psterile = 480 nmnsterile hypothesis disfavoured at 99.8 % C.L. with respect to nm nt nm nt or nmnsterile ? Phys. Lett. B517 (2001) 59 R = (-1< cosQ <-0.7) / (-0.4 <cosQ <0)

7. Best parameters for nm nt Dm2 = 2.3 10-3 eV2 ; sin2 2q =1 Final results(Eur. Phys. J. C36 (2004) 323) { R1= N(cos Q < -0.7) / N(cosQ > -0.4) • Zenith distribution H.E. • En estimate by MCS R2= N(low En) / N(high En) R3= N(ID+UGS) / N(IU) • IU, ID and UGS m L.E. NO OSCILLATION HYPOTHESIS RULED OUT BY ~ 5s 90% C.L. Only 3 ratios Adding the absolute flux information (Bartol96 correct within 17%) 3 ratios + 2 normalizations NO OSCILLATION HYPOTHESIS RULED OUT BY ~ 6s

8. Violation of Lorentz Invariance (VLI) If VLI is introduced, particles could have different Maximum Attainable Velocities (MAVs) vi (p=∞) ≠ c Velocity and flavor eigenstates are now connected by a new mixing angle qv If neutrinos have different MAVs (i.e. Δv = v3-v2 ≠ 0), the survival oscillation probability has the form: P(nm→ nm ) = 1- sin2 2qv sin2 [ 2.54.1018Dv L. En ] Mixed oscillation scenario When both mass-induced and VLI-induced oscillations are simultaneously considered: P(nm→ nm ) = 1- sin2 2Q sin2 W Oscillation “length” Oscillation “strength”

9. Survival probability vs En(L=10000 km , Dm2=2.3.10-3 eV2 , qm= p/4 +0.3 -0.3 Main effect are mass-induced oscillations VLI is considered as a subdominant effect, at least for the accessible energies +0.7 -0.7 +1 -1

10. χ2 analysis Cuts optimized with MC > high

11. Neutrino flux used in MC: Honda et al., Phys Rev. D70 (2004) 043008 Results (Phys. Lett. B615 (2005) 14) Changing Dm2 with Dm2± 30% the limit moves up/down by at most a factor 2 Allowing Dm2 to vary inside ± 30%, qm ± 20% and marginalizing in qv : | Dv | < 3 . 10-25

12. Likelihood analysis Minimization of the function: F = -2 ∑ ln f(Eni,Li ; Dm2,Dv,qm23,qv23) i f(x:a) = K × pMC × p(nm → nm) Event by event analysis to exploit the full information We used the events (106) with the most accurate energy reconstruction : 25 GeV ≤ En ≤ 75 GeV We allowed the oscillation mass parameters to vary along the 90% C.L. final contour of MACRO. For each point of the contour we performed maximum likelihood fits for the VLI parameters

13. Results The 90% C.L. limits obtained from the convolution of the local 90% C.L. upper/lower limits.

14. Search for GUT Magnetic Monopoles • GUT MM, mM ≥ 1016 GeV • Redundancy: 3 different • subdetectors • Sensitivity for catalysis of • nucleon decay induced by MM No candidates were found

15. Flux upper limits for 1gD GUT MMs [Eur. Phys. Jou. C25 (2002) 511] Direct searches ,isotropic flux Flux of GUT MMs in the cosmic radiation:  < 1.4 . 10-16 cm-2 s-1 sr-1 for 4 . 10-5 < b < 1

16. e+ MM • s = 5.10-25 cm2 s = 10-24 cm2 Search for MM-induced proton decay [Eur. Phys. Jou. C26 (2002) 163] M + p →M + e+ + p0 Slow MM track using the streamer tube system S = 4250 m2sr , t = 70000 hours Fast e+ track

17. Search for nuclearites[Eur Phys. Jou. C13 (2000) 453] • Aggregates of u, d, s quarks + electrons • Ground state of nuclear matter • Stable for any barion number 300 < A < 1057 • Candidates for cold Dark Matter White Mt. : 4800 m a.s.l. Mt. Norikura : 2000 m a.s.l. Ohya : 100 hg/cm2 undg. MACRO : 3700 hg/cm2 undg. Search for charged Q-balls :The MACRO limit is ~ 10-16 cm-2 s-1 sr-1, like for nuclearites

18. Search for dark matter WIMPs[Phys. Rev. D60 (1999) 082002 ; hep-ex/9905021] Search of an excess of neutrino events in the directions of the Earth and the Sun No excesses above the n background have been observed. The upper flux limit, F ~ 10-14 cm-2 s-1, excluded an important fraction of the parameters of various supersimmetric models

19. Final : only single tracks Previous (2000) : single+multi-tracks Search for Lightly Ionizing Particles[Phys. Rev. D62 (2000) 052003 ; hep-ex/0402006] Predicted by GUT and some supersimmetric models Searched for with streamer tubes and scintillators No candidates were found

20. Conclusions • Standard (mass) nm oscillations : • No-oscillation hypothesis ruled out at 5-6s • Best parameters for nm → nt : Dm2 = 2.3 . 10-3 eV2 and sin2 2qm =1 • nm→nsterile hypothesis disfavoured at 99.8 % C.L. with respect • to nm → nt • VLI : |Dv| upper limits of the order of 10-25 • GUT Magnetic monopole search : no candidates. Upper flux limit of • ~ 1.4 . 10-16 cm-2 s-1 sr-1 for 4 . 10-5 < b < 1 • Best existing limit in direct searches! • Nuclearite search : no candidates. Upper flux limit of • ~ 10-16 cm-2 s-1 sr-1 for b ~ 10-3 • Charged Q-balls search : no candidates. Upper flux limit of • ~ 10-16 cm-2 s-1 sr-1 • WIMP search : no candidates. Upper flux limit of ~ 10-14 cm-2 s-1 • LIP search : no candidates. Upper flux limit of ~ 6.1.10-16 cm-2 s-1 sr-1