1. 1 MINOS/NuMI projects ● Introduction to kingdom MINOS/NuMI ● Physics goals of MINOS ● Kingdom built ● NuMI beamline ● MINOS detectors ● Running the kingdom - data taking ● Atmospheric ● Beam ● Summary Hai Zheng CaltechMINOS King Minos holding the sceptre that Zeus himself gave him

2. 2 Near Detector 980 Tons measure the beam energy spectrum Fermilab, IL Far Detector 5.4 kTons measure the oscillation Soudan, MN Introduction  MINOS is an accelerator-based Long-Baseline neutrino experiment to study   oscillation  with high statistics  ’s are generated at Fermilab from 120 GeV protons and delivered by the NuMI beamline Both detectors have magnetic fields: first large underground detectors to identify  - and  + separately Detector 2 Detector 1 735 km

3. 3 MINOS Physics goals  m 2 23     disappearance : –Confirm oscillations –Precise Measurement of sin 2 (2 23 ) &  m 2 23 : ● P oscillation sin 2 (2 23 )sin 2 (1.27m 2 23 L /E) ● Goal: 1  precision 3-5% Search for  e appearance: Might be able to observe e appearance Atmospheric  measurements and capable of first direct observation of separated atmospheric ν and ν oscillations P(   e sin 2 (2 13 )sin 2 ( 23 )sin 2 (1.27m 2 L/E)

4. 4 MINOS sensitivity for  m 2 and sin 2 2  location & depth of the signal yield  m 2 & sin 2 2  measurements be able to rule out non-oscillation models precision improves with additional protons For  m 2 = 0.0025eV 2, sin 2 2  = 1.0 Oscillation measurement:  Compare the observed  energy spectrum at the far detector to the expected un-oscillated spectrum calculated from the near detector measurement Left: the ratios of oscillated to un- oscillated spectrum signal

5. 5 MINOS Sensitivity to e Appearance For  m 2 = 0.0025 eV 2, sin 2 2  13 = 0.067 Assuming 25 x 10 20 protons on target Background dominated by Neutral current interactions (+ some intrinsic beam  e ’s) Energy Spectrum  m 2 = 0.0025 eV 2 detection of e at  m 2 atm  evidence for non-zero  13 Can improve 90% CL  by a factor of ~2 with higher proton intensity

6. 6 NuMI – MINOS @ Fermilab Tevatron Main Injector Booster Target Enclosure Decay Enclosure MINOS Near Detector To Soudan Mine NuMI Beamline To transport protons to the target & generate the beam Designed for up to 4 x 10 13 protons/pulse Earlier commissioning: ● Delivered low proton intensity on the target with low repetition rate February 18-March 23, 2005: Varied energy spectra by moving the targetVaried energy spectra by moving the target MI was operating w/ high proton intensityMI was operating w/ high proton intensity reached up to 2.5 x 10 13 pppreached up to 2.5 x 10 13 ppp Repetition rate was increased to nominal rate of 0.5 HzRepetition rate was increased to nominal rate of 0.5 Hz Main Injector (MI) goal for this year accelerate 2.5 x 10 13 protons every 2 seconds to 120 GeV ~8  sec spill, 0.25MW

7. 7 NuMI Beamline Layout & components Components Layout Aimed downwards at 58 mrad toward the Soudan mine Protons hit segmented graphite target & charged hadron beam is focused with two magnetic horns 675m long steel vacuum decay pipe Hadron monitor and hadron absorber downstream of decay pipe 200m rock upstream of Near Detector for muon absorption & muon monitors 207 m Protons π, K

8. 8 Horn 2 6.4 x 15 mm 2 ~1 m long: 2 interaction lengths Graphite target w/ water cooling tube target vessel (vacuum) with beryllium window Target and Horns Back face of horn 2 Assembled horn 1 Parabolic shape of inner horns gives focusing 200 kA peak current 3 Tesla peak field 1.87 sec repetition rate(designed)

9. 9 Target Water Leak Water-cooled graphite fins sit inside a vacuum chamber Target was filled with water in March, investigated Leak self-repaired, target back in, operations resumed. –Leak reappeared, now back pressuring helium –2 nd target will be ready in Aug. –Building another spare target –Interesting facts learned: Beam scans across the target confirm extra material (proton radiography) Attenuation through water? Water Filling Target Can Water Being Pumped from Target Can Multiple scattering through H 2 O baffle target baffle

10. 10 Can change the energy spectrum by moving the target (shown in plots), or by moving horn 2, but needs more work NuMI  eam Running Target is inside horn 1 (LE) 2.5 x 10 20 protons/year produces ~1600  CC events in FD assuming no-oscillation Energy spectra for different target positions Data acquisition was stopped because of water leak in the target

11. 11 60-plane ‘micro - MINOS’ -- has taken data at T7 & T11 test beam lines at CERN during 2001, 2002, 2003 MC expectation Calibration Detector

12. 12 Far Detector 8m octagonal tracking Calorimeter 486 planes (5.4 kTon total) 2 super modules(SM) : 15 m long each Toroidal B-field: 1.3 T at r = 2m Veto shield for cosmic  ’s Completed in July 2003 Recording cosmic ray muons since 2002 Plane with scintillators installed Completed Far Detector

13. 13 Near Detector at Fermilab Completed Near Detector Partial planeFull plane Same basic design as the far detector but smaller 282 single steel planes 980 Tons Combination of partially & fully instrumented planes ● Calorimeter (120 planes) is partially instrumented except for 1/5 of planes with full coverage ● Spectrometer (162 planes) has only every 5 th plane instrumented Plane assembly was completed in August 2004

14. 14 MINOS Running To ensure smooth running of the long baseline neutrino experiment, we need good coordination and monitoring between near and far sites Experts on-call Fermilab main control room – physicist shifters Soudan control room – now mainly mine crew, not 24/7 Collaboration with Fermilab accelerator division on different projects for better beam quality and high intensity beam NuMI beam monitoring and instruments MI/Booster upgrade and improvements, such as: damper system to reduce oscillation amplitude cogging to synchronize Booster extraction with MI with multi-batch operation and many more... Proton intensity, such as barrier RF stacking and slip stacking Overlapping collaborators with experiments such as MIPP, MINER A,  with broader scope of neutrino physics in mind

15. 15 Atmospheric Since completion in August 2003 the Far Det has been taking atmospheric neutrino data. Beam switched on 1st March 2005 at which point the Far Detector had collected 420 days of physics quality data, excellent for a detector still in commissioning stage. Total of 6.18 kton-years of data suitable for atmospheric neutrino studies, c.f. Soudan 2's 7.36 kton-years Will still take atmospheric neutrino data during beam running. Publication coming soon, stay tuned! MINOS PRELIMINARY DAT A V vs Z ADC vs Z Time vs Z (2.4 ns) U vs Z stopping  with veto hits

16. Example Events Fully Contained Partially Contained Downward Going ν induced μ Partially Contained Upward Going

17. 17 Accumulating beam data at both detectors !!!

18. 18 Incoming Direction for Near Detector Neutrinos Zenith and azimuth show point of origin of the neutrinos within spill time Beam points downward 3.3 degrees, expect peak at cosθ = 0.06 Beam also points west of north, expect peak at 156 degrees Neutrinos definitely coming from the beam! S EW18090 270 θ Near Det. Thousands of 's already!

19. 19 2.5  10 12 protons/1.6  s spill Separation of two categories of interactions: Interaction inside of the near detector: Fully contained event  from interaction in the rocks surround the near detector: Rock   this one goes through the whole detector Interactions of the beam in Near Detector Beam direction MINOS preliminary Back view v u u view v view

20. 20 First beam event at Far Detector: Rock  Event seen in both SuperModule1 & SuperModule2 Charge identification from curvature :  - Detected  momentum ~12 GeV from curvature & the # of planes the track passed Entrance point x y B Beam direction MINOS preliminary u view v view

21. 21 First Fully Contained Event in Far Detector Beam direction Showering event (Neutral Current candidate?) MINOS preliminary discovered by our Greek collaborator at the end of March

22. 22 More Far Detector Events Beam direction Charged current quasi-elastic scattering candidate n  p? MINOS preliminary

23. 23 More Far Detector Events MINOS preliminary Freshly produced in May Another Charged Current Candidate

24. 24 More Far Detector Events MINOS preliminary Freshly produced in May, from the same run Showering Event ( e Candidate?)

25. 25 Summary ● NuMI beamline is completed and commissioned ● 2.5x10 13 protons/spill & 0.5 Hz repetition rate have been achieved separately ● Water leak in target investigated and under control ● MINOS detectors are completed & operating ● acquiring atmospheric ’s with over 90% live time, first publication coming out soon! ● beam data-taking at both detectors precise measurement of  m 2 and sin 2 2  search for non-zero   by detecting  e appearance ● Minoans have been working hard and eagerly await the final judgment

26. `Thus I descended from the first circle down into the second, which girdles less space, and so much more woe that it goads to wailing. There abides Minos horribly, and snarls; he examines the sins at the entrance; he judges, and he sends according as he entwines himself.' Dante Alighieri - Divina Commedia Gustave Dore