Recent Results from the MINOS experiment

MINOS is an accelerator neutrino oscillation experiment at Fermilab. An intense high energy neutrino beam is produced at Fermilab and sent to a near detector on the Fermilab site and also to a 5 kTon far detector 735 km away in the Soudan mine in northern Minnesota. The experiment has now had several years of running with millions of events in the near detector and hundreds of events recorded in the far detector. I will report on the recent results from this experiment which include precise measurement of $|\Delta m^2_{32}|$, ~analysis of neutral current data to limit the component of sterile neutrinos, and the search for $\nu_\mu \to \nu_e$ conversion. The focus will be on the analysis of data for $\nu_\mu \to \nu_e$ conversion. Using data from an exposure of $3.14\times 10^{20}$ protons on target, we have selected electron type events in both the near and the far detector. The near detector is used to measure the background which is extrapolated to the far detector. We have found 35 events in the signal region with a background expectation of $27\pm 5(stat)\pm 2(syst)$. Using this observation we set a 90% C.L. limit of $\sin^2 2 \theta_{13} < 0.29$ for $\delta_{cp} = 0$ and normal mass hierarchy. Further analysis is under way to reduce backgrounds and improve sensitivity.Comment: This was prepared for the proceedings of the XIII International Workshop on Neutrino Telescopes at the Istituto Veneto di Scienze, Lettere ed Arti in Venice, Italy held on March 10-13, 2009. The presentation was on behalf of the MINOS collaboratio

Muon Decay Asymmetries from KL0→π0μ+μ−K^0_L \to \pi^0 \mu^+ \mu^- Decays

We have examined the decay $K^0_L \to \pi^0 \mu^+ \mu^-$ in which the branching ratio, the muon energy asymmetry and the muon decay asymmetry could be measured. In particular, we find that within the Standard Model the longitudinal polarization ($P_L$) of the muon is proportional to the direct CP violating amplitude. On the other hand the energy asymmetry and the out-of-plane polarization ($P_N$) depend on both indirect and direct CP violating amplitudes. Although the branching ratio is small and difficult to measure because of background, the asymmetries could be large $\cal{O}$(1) in the Standard Model. A combined analysis of the energy asymmetry, $P_L$ and $P_N$ could be used to separate indirect CPV, direct CPV, and CP conserving contributions to the decay.Comment: 6 pages, 4 figures, To be Published in Physical Review

Status of the MINOS experiment

I will present the status of the long baseline neutrino oscillation experiment MINOS at Fermi National Accelerator Laboratory (Fermilab). I will summarize the status of the detector and beam construction, the expected event rates and sensitivity to physics. I will also comment on possible future plans to improve the performance of the experiment.Comment: Invited talk at the Seventh International Workshop on Tau Lepton Physics (TAU02), Santa Cruz, Ca, USA, Sept 2002, 7 pages, 6 figures, LaTeX Higher res figures at http://minos.phy.bnl.gov/~diwan/tau02_th08.p

Measurement of Longitudinal Electron Diffusion in Liquid Argon

We report the measurement of longitudinal electron diffusion coefficients in liquid argon for electric fields between 100 and 2000 V/cm with a gold photocathode as a bright electron source. The measurement principle, apparatus, and data analysis are described. Our results, which are consistent with previous measurements in the region between 100 to 350 V/cm [1] , are systematically higher than the prediction of Atrazhev-Timoshkin[2], and represent the world's best measurement in the region between 350 to 2000 V/cm. The quantum efficiency of the gold photocathode, the drift velocity and longitudinal diffusion coefficients in gas argon are also presented.Comment: Accepted by NIM on January 29th. 201

Prompt neutrinos from the atmosphere to the forward region of LHC

We investigate the kinematical regions that are important for producing prompt neutrinos in the atmosphere and in the forward region of the LHC, as probed by different experiments. We illustrate the results as a function of the center-of-mass nucleon-nucleon collision energies and rapidities of neutrinos and of the parent heavy-flavoured hadrons. We find overlap in part of the kinematic space.Comment: 6 pages, 3 figures, talk at "The European Physical Society Conference on High Energy Physics (EPS-HEP2023)", 21-25 August 2023, Hamburg, Germany; submitted to PoS - Proceedings of Scienc