Presentation is loading. Please wait.

Presentation is loading. Please wait.

MINOS Feb 28 20061 Antineutrino running Pedro Ochoa Caltech.

Published by Modified over 9 years ago

Similar presentations

Presentation on theme: "MINOS Feb 28 20061 Antineutrino running Pedro Ochoa Caltech."— Presentation transcript:

1 MINOS Feb 28 20061 Antineutrino running Pedro Ochoa Caltech

2 MINOS Feb 28 20062 Generate flux files with inverse horn current (GNUMI v18, -10.0 from nominal, -185kA) Generate MC files (GMINOS) Reconstruct MC files (R1.18.2) 1e7 POT of flux generated (used fluka files in /afs/fnal.gov/files/data/minos/d110 /fluka_hadrons/fluka05_xxx.ntp) 200e20 POT generated 200e20 POT reconstructed Reverse horn current MC generation Q: What could we do if we ran in antineutrino mode?  Generated some MC with inverted horn current: (Special thanks to Alysia M. !!)

3 MINOS Feb 28 20063 1e20 POT Neutrinos Antineutrinos Energy spectra comparison Neutrinos Antineutrinos A B A: red  Neutrinos in neutrino mode blue  Antineutrinos in antineutrino mode B: red  Neutrinos in antineutrimo mode blue  Antineutrinos in neutrino mode

4 MINOS Feb 28 20064 Negative log likelihood analysis In order to get an idea of how well we could do an antineutrino oscillation analysis (and thus a CPT violation measurement) with this data I performed a negative log likelihood analysis with the following basics: For a given input parameter (typically  m2=0.002 and sin2(2θ)=1) an expected energy spectrum is obtained and then fluctuated statistically by a Poisson. 800 pseudo-experiments are obtained in this fashion. Each pseudo-experiment spectrum is compared to the different spectra generated for various combinations of  m2,sin2(2θ) by the means of a negative log likelihood: The average –log(L) is then obtained for each combination of  m2,sin2(2θ) and the minimum is substracted. The 2.3 contour gives an approximate ~90% confidence limit. A complete “recipe” can be found at http://minos-docdb.fnal.gov:8080/cgi- bin/ShowDocument?docid=1422, slide 4.http://minos-docdb.fnal.gov:8080/cgi- bin/ShowDocument?docid=1422

5 MINOS Feb 28 20065 (q/p)/(σ q/p) for planes > 25 Antineutrino selection method Neutrinos Antineutrinos It was necessary to come up with an antineutrino selection method. Selected antineutrinos that satisfy: - At least 1 track - Track must intersect 25 planes min. - Track must pass fit - Track must have (q/p)/(σ q/p)>2 The method has an efficiency of 73.6%. The remaining background is 5.6%. Planes crossed Background components This method is certainly not optimized, and much work remains to be done in this area !

6 MINOS Feb 28 20066 The results The results show a high dependence on the effectiveness of the selection cuts. Therefore, for completeness purposes and in order to separate the effects that the selection, the energy resolution and the statistics have, the results in the following pages have three different contours: 1)A “realistic” contour, in which the selection cuts described in the previous slide are applied and the reconstructed energy is used. 2)An “ideal” contour, where the selection efficiency is taken to be 100% and no background is considered, but the reconstructed energy is used. 3)A “best possible” contour, which is obtained like the “ideal” one but using the true energy. This gives the best case scenario.

7 MINOS Feb 28 20067 Input value: Realistic Ideal Best possible 1.0e20 of running alone: 1.0e20 POT

8 MINOS Feb 28 20068 Input value: Realistic Ideal Best possible 6.0e20 of running alone: 6.0e20 POT

9 MINOS Feb 28 20069 Realistic Ideal Best possible Combining 1e20 POT of running and 6e20 POT of normal running: Antineutrino running Neutrino running

10 MINOS Feb 28 200610 More results… Input value: Realistic Ideal Best possible Realistic Ideal Best possible Realistic IdealBest possible

11 MINOS Feb 28 200611 200e20 POT of carrot-equivalent reversed horn current data was produced and analyzed. The possibility of running in antineutrino mode is worth of consideration, as its combination with antineutrinos from normal running may provide a reasonable calculation of Δm2(bar) Next step to a fuller treatment of antineutrino running is to include systematics. This may not be very easy due to the different contributions from neutrino running and antineutrino running. Summary & Ongoing Work Antineutrino running:

12 MINOS Feb 28 200612 A preliminary look at the double ratio method for measuring  transitions C. Howcroft & P. Ochoa Caltech

13 MINOS Feb 28 200613 Basic idea The basic idea of this method is to compare the ratio of antineutrinos to neutrinos in both detectors to make a measurement of transitions: 1) The carrot MC production in the L010185 configuration was used. 2) The results shown in this talk represent the best possible scenario since: - Assumed perfect energy resolution - Assumed 100% selection efficiency - No oscillation depletion taken into account - No systematics considered - Assumed 16e20 POT Purpose of this work was to be a first step towards a fuller analysis by: ● determining how we expect K to be given the most recent MC. ● getting an idea of how statistically limited we are. Please note that: K can be determined using MC (or maybe using small fiducial region in ND)

14 MINOS Feb 28 200614 Expected (MC) spectra at 16.0e20 POT These are the histograms of true energy of true (anti)neutrinos in the ND used for the calculations. ND Near detector: Error bars are statistical error based on the MC statistics used and scaled accordingly. Both plots are scaled to 16.0e20 POT Only the n140 files were used, i.e. no overlay and fiducial volume interactions only.

15 MINOS Feb 28 200615 FD Far detector: Both plots are scaled to 16.0e20 POT These are the histograms of true energy of true (anti)neutrinos in the FD used in the calculation. No oscillation effect was considered.

16 MINOS Feb 28 200616 Expected (MC) ratio of antineutrinos to neutrinos From the expected energy spectra we can obtain the expected ratio in both detectors and compare them to each other: ratio ND FD This is the expected (MC) K of slide 12, subsequently referred to as “expected double ratio”

17 MINOS Feb 28 200617 Pseudo-experiment generation Need to be able to determine how much deviation can be expected from the expected double ratio due to statistics. In order to do that, took the 4 expected (anti)neutrino spectra (neutrinos in the FD and ND, and antineutrinos in the FD and ND), and fluctuated them statistically with a Poisson distribution. The process was repeated 10,000 times. FDND 3 fluctuations shown

18 MINOS Feb 28 200618 Each time, the double ratio is calculated and the following histograms filled: Expected double ratio Divide by expected double ratio Would need to see, at the very least, a ~50% effect in order to claim something is there !! 90% C.L. 98% C.L. double ratio(double ratio)/(expected double ratio) Doing the same at 6e20 POT

19 MINOS Feb 28 200619 Sensitivity to transition probability Neutrinos disappear in usual way: But now a fraction α of the disappeared neutrinos goes to antineutrinos: Also tried to roughly determine up to what percentage of transitioned neutrinos we could have a sensitivity to in MINOS. For that invented a toy model: A negative log likelihood analysis was done, with α as a unique parameter. It was found that for the input value of α~0.1 and smaller, the transition scenario is indistinguishable from no transitions at all. Neutrinos: - All (MC) - That transition (MC) - That will appear as antineutrinos α=0.1 -Δlog(L)=2.3 (16e20 POT assumed)

20 MINOS Feb 28 200620 Summary & Ongoing Work Using a toy model it was found that MINOS should be able to see if ~10% (or more) of the neutrinos that disappear in the usual way transition to antineutrinos. The MC expectation value of the double ratio (antineutrinos to neutrinos was quantified with the latest version of the MC. Just based on statistics, it seems we would need to see a variation of more than ~50% in the double ratio in order to claim new physics at 16e20 POT. Will work on adding other things to the calculation (selection efficiencies, backgrounds, systematics…). Also have to work on a good antineutrino selection method. Neutrino-antineutrino transitions:

21 MINOS Feb 28 200621 Extra: one could deal with fractions instead of ratios. May try this later FDND

Download ppt "MINOS Feb 28 20061 Antineutrino running Pedro Ochoa Caltech."

Similar presentations

Expected Sensitivity of the NO A  Disappearance Analysis Kirk Bays (Caltech) for the NO A Collaboration April 14, 2013 APS DPF Denver Kirk Bays, APS DPF.

Expected Sensitivity of the NO A  Disappearance Analysis Kirk Bays (Caltech) for the NO A Collaboration April 14, 2013 APS DPF Denver Kirk Bays, APS DPF.
London Collaboration Meeting September 29, 2005 Search for a Diffuse Flux of Muon Neutrinos using AMANDA-II Data from 2000 - 2003 Jessica Hodges University.

London Collaboration Meeting September 29, 2005 Search for a Diffuse Flux of Muon Neutrinos using AMANDA-II Data from Jessica Hodges University.
Reconstruction Issues in Cosmic Ray Muons Maury Goodman/Gavril Giurgiu & Jurgen Reichenbacher.

Reconstruction Issues in Cosmic Ray Muons Maury Goodman/Gavril Giurgiu & Jurgen Reichenbacher.
Sinergia strategy meeting of Swiss neutrino groups Mark A. Rayner – Université de Genève 10 th July 2014, Bern Hyper-Kamiokande 1 – 2 km detector Hyper-Kamiokande.

Sinergia strategy meeting of Swiss neutrino groups Mark A. Rayner – Université de Genève 10 th July 2014, Bern Hyper-Kamiokande 1 – 2 km detector Hyper-Kamiokande.
1 A preliminary estimate of the beam e ’s from antineutrinos David Jaffe, Pedro Ochoa December 7 th 2006.

1 A preliminary estimate of the beam e ’s from antineutrinos David Jaffe, Pedro Ochoa December 7 th 2006.
Off-axis Simulations Peter Litchfield, Minnesota  What has been simulated?  Will the experiment work?  Can we choose a technology based on simulations?

Off-axis Simulations Peter Litchfield, Minnesota  What has been simulated?  Will the experiment work?  Can we choose a technology based on simulations?
CC analysis progress This talk: –A first attempt at calculating CC energy sensitivity using the Far Mock data MC files with full reconstruction. –Quite.

CC analysis progress This talk: –A first attempt at calculating CC energy sensitivity using the Far Mock data MC files with full reconstruction. –Quite.
1 Using the pHE data to measure the beam e ’s from  + decay David Jaffe and Pedro Ochoa March 13 th 2007  Introduction  Antineutrino selection  Feasibility.

1 Using the pHE data to measure the beam e ’s from  + decay David Jaffe and Pedro Ochoa March 13 th 2007  Introduction  Antineutrino selection  Feasibility.
Selection: i) Used “basic cuts” described in my NuBarPID talk (slide 3). 74.4% of CC events pass this cut. ii) Used David’s PID cut at -0.2 to remove NC.

Selection: i) Used “basic cuts” described in my NuBarPID talk (slide 3). 74.4% of CC events pass this cut. ii) Used David’s PID cut at -0.2 to remove NC.
1 Using the pHE data to measure the beam e ’s from  + decay David Jaffe and Pedro Ochoa April 12 th 2007  Reminder  Systematic from background  Horn.

1 Using the pHE data to measure the beam e ’s from  + decay David Jaffe and Pedro Ochoa April 12 th 2007  Reminder  Systematic from background  Horn.
Update on NC/CC separation At the previous phone meeting I presented a method to separate NC/CC using simple cuts on reconstructed quantities available.

Update on NC/CC separation At the previous phone meeting I presented a method to separate NC/CC using simple cuts on reconstructed quantities available.
MINOS 1 Beam e ’s from antineutrinos David Jaffe and Pedro Ochoa September 27 th 2007  Preliminaries  Data & MC  Expected sensitivities  Preliminary.

MINOS 1 Beam e ’s from antineutrinos David Jaffe and Pedro Ochoa September 27 th 2007  Preliminaries  Data & MC  Expected sensitivities  Preliminary.
First Observations of Separated Atmospheric  and  Events in the MINOS Detector. A. S. T. Blake* (for the MINOS collaboration) *Cavendish Laboratory,

First Observations of Separated Atmospheric  and  Events in the MINOS Detector. A. S. T. Blake* (for the MINOS collaboration) *Cavendish Laboratory,
Far Detector Fiducial Volume Studies Andy Blake Cambridge University Saturday February 24 th 2007.

Far Detector Fiducial Volume Studies Andy Blake Cambridge University Saturday February 24 th 2007.
2015/6/23 1 How to Extrapolate a Neutrino Spectrum to a Far Detector Alfons Weber (Oxford/RAL) NF International Scoping Study, RAL 27 th April 2006.

2015/6/23 1 How to Extrapolate a Neutrino Spectrum to a Far Detector Alfons Weber (Oxford/RAL) NF International Scoping Study, RAL 27 th April 2006.
NuMI Offaxis Near Detector and Backgrounds Stanley Wojcicki Stanford University Cambridge Offaxis workshop January 12, 2004.

NuMI Offaxis Near Detector and Backgrounds Stanley Wojcicki Stanford University Cambridge Offaxis workshop January 12, 2004.
25 April 20061 Antineutrino selection for constraining the e beam Goal: extract component of  rate from  + decays Requirement: High purity at low neutrino.

25 April Antineutrino selection for constraining the e beam Goal: extract component of  rate from  + decays Requirement: High purity at low neutrino.
1 Beam e ’s from antineutrinos using the pME and LE beams David Jaffe, Pedro Ochoa December 8 th 2006  Part 1: Reminder and update  Part 2: Change in.

1 Beam e ’s from antineutrinos using the pME and LE beams David Jaffe, Pedro Ochoa December 8 th 2006  Part 1: Reminder and update  Part 2: Change in.
CC/NC SEPARATION STUDY Andy Blake Cambridge University Friday February 23 rd 2007.

CC/NC SEPARATION STUDY Andy Blake Cambridge University Friday February 23 rd 2007.
1 Latest CC analysis developments New selection efficiencies: –Based on C++ reco + PDFs rather than old (Fortran+reco_minos) cuts –Attempt to optimise.

1 Latest CC analysis developments New selection efficiencies: –Based on C++ reco + PDFs rather than old (Fortran+reco_minos) cuts –Attempt to optimise.

Similar presentations

Ads by Google