1. Tracking

Small-Fine-Calibration

2. Monte Carlo Fine Tuning

3. Measurement of the Likelihood efficiency

Paolo Beltrame

for ppg group

Phi decay meeting 30.05.07

1. Tracking

Small-Fine-Calibration

Methods

1. Collinear events  expected vs observed momentum quantities

High Mpp2 region

2. p0 Mass  p+p-p0 Missing Mass

Low Mpp2 region

Collinear events DATA “sample”

- 2002: Venanzoni's CLB prod2ntu-ntuples (for collinear events),

standard stentu-ntuples (for Trackmass)

- 2006: standard stentu-ntuples (abundance of collinear events)

- Müller's DATA run quality applied (2002 DATA only) and new ppgtag

- Condition on first hit: rFirst Hit < 50 cm

- Condition on PCA: rPCA < 8 cm, |zPCA| < 12 cm

(selecting, for 2002, tracks from DTFS with the same ID of tracks making the vertex)

- Condition on vertex: rvtz < 12 cm, |zvtx| < 7 cm

- Cut on spiraling tracks

- .and. of the Likelihood

- Tracks in the angular region 50 < q < 130 

Collinear event selection

Mpp2 > 0.95 GeV2

no prompt photon detected

DfCM = p - | f+CM - f-CM | < 0.5

DqCM = p - | q+CM + q- CM| < 0.5

DpCM = |pCM+| - |pCM-| < 5 MeV

ppp events “sample”

- 2002: standard 3pstream-ntuples

- 2006: Venanzoni's ppp MC 2006 prod2ntu-ntuples

- Müller's DATA run quality applied (2002 DATA only)

- Condition on first hit: rFirst Hit < 50 cm

- Condition on PCA: rPCA < 8 cm, |zPCA| < 12 cm

(selecting, for 2006, tracks from DTFS with the same ID of tracks making the vertex)

- Condition on vertex: rvtz < 12 cm, |zvtx| < 7 cm

- Cut on spiraling tracks

- .and. of the Likelihood

- Tracks in the angular region 50 < q < 130 

ppp event selection

0 < c2 < 50

2002 DATA

s  s (no 150 KeV correction)

2006 DATA

2006: s  s –240KeV (Müller's f-lineshape fit)

s

DATA 2002

Collinear Events

in the CM system

DpCM (MeV)

DqCM ()

DfCM ()

Mean value of the gaussian fits

DpCM = (0.270  0.011) MeV

DqCM = (-0.0161  0.0098)

DfCM = (0.0145  0.0009)

Hint of tiny miscalibration?

DATA 2002

DATA 2002

Collinear Events

in the CM system

Dpx CM (MeV)

Dpy CM (MeV)

Dpz CM (MeV)

Mean value of the gaussian fits

Dpx CM = (0.177  0.011) MeV

Dpy CM = (0.018  0.011) MeV

Dpz CM = (-0.171  0.008) MeV

Hint of tiny miscalibration?

Hint of tiny miscalibration?

pi+CM - pi- CM = Dpi CM

DATA 2002

Expected vs Observed quantities

for collinear events

1. Expected and observed momentum ee   hypothesis

CM system

positive track (-0.260  0.014) MeV

2. Expected and observed track-boost angle ee   hypothesis (|Mtrk – mp| < 20 MeV)

LAB system

Expected

Observed

Eb: Total energy from

the beams

pb: boost

positive track (-2.66  0.007) 

z

x

y

pb

ptrk

a

Momentum SFC

steps

0. z component fixed

1. agreement between expected and observed values: Dp and Da

2. check the effect on:

- 2002  missing mass for ppp DATA events

 Trackmass for ppg DATA events

- 2006  Trackmass for ppg DATA

Trackmass value to obtain  MC kine

3. go back to 1. and see “di nascosto l'effetto che fa”

4. reach a compromise

2002

pz miss = (0.01  0.007) MeV

Other variables of collinear events

also good  peaked at zero

pz miss

DATA 2002

- s  s (as it is from the bank: no 150 KeV correction)

- Corrections on momenta :

positive pz pz+|pz|·5·10-4, px,y px,y·(1-7·10-4)

negative pz pz+|pz|·4·10-4, px,y px,y·(1-2·10-4)

Expected vs Observed quantities

for collinear events (2002)

1. Expected and observed momentum ee   hypothesis

pexp – p+obs (MeV)

pexp – p-obs (MeV)

(-0.030  0.005) MeV

(-0.009  0.005) MeV

DATA 2002

CM System

2. Expected and observed track-boost angle ee   hypothesis (|Mtrk – mp| < 20 MeV)

Expected

Observed

Eb: Total energy from

the beams

pb: boost

(-0.25  0.06)

aexp – a+obs ()

aexp – a-obs ()

(0.21  0.06)

DATA 2002

LAB System

- s from the bank

- Momentum corrections (from collinear events)

- Condition on first hit, on PCA and vertex

- Cut on spiraling tracks

- .and. of the Likelihood

- Tracks at Large Angle

- c

Looking at physical quantities (DATA 2002): p+p-p0

(134.98  0.03) MeV

Mmiss (MeV)

DATA 2002

Mmiss (MeV)

(134.97  0.05) MeV

stentu

3p stream

Fit range: 125–145 MeV

Without SFC

Mmiss = 134.2 MeV

Looking at physical quantities (DATA 2002): TRACKMASS

- s from the bank

- Momentum corrections (from collinear events)

- Condition on first hit, on PCA and vertex

- Cut on spiraling tracks

- .and. of the Likelihood

- Tracks at Large Angle

(139.66  0.02) MeV

DATA 2002

Mtrk (MeV)

Mtrk (MeV)

(139.70  0.04) MeV

Large angle

Small angle

Without SFC

Mtrk = 139.5 MeV

2002 ppg MC kine

Mtrk = 139.67 MeV

2006

pz miss = (0.020  0.005) MeV

Other variables of collinear events

also good  peaked at zero

pz miss

DATA 2006

- s  s -240KeV (Müller's f-lineshape fit)

- Corrections on momenta :

positive pz pz+|pz|·6·10-4, px,y px,y·(1-4·10-4)

negative pz pz+|pz|·5·10-4, px,y px,y·(1+3·10-4)

Expected vs Observed quantities

for collinear events (2006)

1. Expected and observed momentum ee   hypothesis

pexp – p+obs (MeV)

pexp – p-obs (MeV)

(-0.043  0.004) MeV

(-0.011  0.004) MeV

DATA 2006

CM System

2. Expected and observed track-boost angle ee   hypothesis (|Mtrk – mp| < 20 MeV)

Expected

Observed

Eb: Total energy from

the beams

pb: boost

(-0.21  0.03)

aexp – a+obs ()

aexp – a-obs ()

(0.01  0.03)

DATA 2006

LAB System

Looking at physical quantities (DATA 2006): TRACKMASS

- s correction

- Momentum corrections (from collinear events)

- Condition on first hit, on PCA and vertex

- Cut on spiraling tracks

- .and. of the Likelihood

- Tracks at Large Angle

(139.75  0.02) MeV

DATA 2006

Mtrk (MeV)

Mtrk (MeV)

(139.85  0.03) MeV

Large angle

Small angle

Without SFC

Mtrk = 140.2 MeV

2006 ppg MC kine

Mtrk = 139.86 MeV

A “practical” summary

- Momentum Small Fine Calibrations for DATA 2002 and 2006 in usable status

(... trying to correct as less as you can)

- DATA 2002

1- no s correction

2- boost has not been touched

3- momenta:

- corrections: (1  O(10-4)) with respect to the momentum  0 - ~100 KeV

(seldom ~200KeV)

- bigger for the positive tracks

- DATA 2006

1- s corrected according to the f-lineshape fit

2- boost has not been touched

3- momenta:

- corrections: (1  O(10-4)) with respect to the momentum  0 - ~100 KeV

- symmetric for both tracks, apart the same shift on z component

- Comparison with Monte Carlo and MC fine tuning (if needed) in progress... next slides

2. Monte Carlo Fine Tuning

Standard procedure  take DATA as they are and tune the MC on them

TRYING A DIFFERENT APPROACH WITH MORE TOOLS

1. DATA  “Small Fine Calibration”: DATASFC

2. MC As It Is

 2.1 Bini-Valeriani's Corrections MCBV

 2.2 (2)007's Corrections MC007

DATA-MC comparisons in the different configurations

DATA & MC sample

- DATA 2002: stentu-ntuples

- Monte Carlo 2002:

 official ppg, mmg, ppp (BhaBha negligible with

“.and. of the Likelihood”)

Some selection cuts

- Condition on first hit: rFirst Hit < 50 cm

- Condition on PCA: rPCA < 8 cm, |zPCA| < 12 cm

- Condition on vertex: rvtz < 12 cm, |zvtx| < 7 cm

- Cut on spiraling tracks

- .and. of the Likelihood

- Tracks in the angular region 50 < q < 130 

- 0 < qS < 15 or 165 < qS < 180

DATA SFC effect (Mtrk vs qp)

Mtrk

MCs 2002

DATA 2002

qp+

Mtrk

qp+

DATA

DATASFC

- Monte Carlo 2002: ppg, mmg, ppp

- No corrections applied

- Small angle angular cuts

- DATA 2002

- Without and with

Small Fine calibrations

- Small angle angular cuts

DATA Small Fine Calibrations

positive pz pz+|pz|·5·10-4, px,y px,y·(1-7·10-4)

negative pz pz+|pz|·4·10-4, px,y px,y·(1-2·10-4)

Mtrk

MCs 2002

DATA 2002

DATA SFC effect (Mtrk vs Mpp2)

- Monte Carlo 2002: ppg, mmg, ppp

- No corrections applied

- Small angle angular cuts

- DATA 2002

- Without and with

Small Fine calibrations

- Small angle angular cuts

Mtrk

Mpp2 (GeV2)

Mpp2 (GeV2)

DATA

DATASFC

DATA Small Fine Calibrations

positive pz pz+|pz|·5·10-4, px,y px,y·(1-7·10-4)

negative pz pz+|pz|·4·10-4, px,y px,y·(1-2·10-4)

Mtrk

qp+

Mtrk

qp+

MCBV

MC007

MCs 2002

DATA 2002

MCBV & MC007 effects (Mtrk vs qp)

- Monte Carlo 2002: ppg, mmg, ppp

- BV or 007

- Small angle angular cuts

- DATA 2002

- Small Fine calibrations

- Small angle angular cuts

MC (2)007 Tuning

- Small correction on momenta: p  p (1+ O(10-4))

- Small smearing in three different Mpp2 regions

DATASFC

DATASFC

MCBV & MC007 effects (Mtrk vs Mpp2)

- Monte Carlo 2002: ppg, mmg, ppp

- BV or 007

- Small angle angular cuts

- DATA 2002

- Small Fine calibrations

- Small angle angular cuts

Mtrk

MCs 2002

DATA 2002

Mtrk

Mpp2 (GeV2)

Mpp2 (GeV2)

MCBV

MC007

DATASFC

DATASFC

MC (2)007 Tuning

- Small correction on momenta: p  p (1+ O(10-4))

- Small smearing in three different Mpp2 regions

- Monte Carlo 2002: ppg, mmg, ppp

- BV or 007

- Small angle angular cuts

- DATA 2002

- Small Fine calibrations

- Small angle angular cuts

sMtrk

MCs 2002

DATA 2002

Mpp2 (GeV2)

Mpp2 (GeV2)

MCBV

MC007

sMtrk

MCBV & MC007 effects (Widths vs Mpp2)

DATASFC

DATASFC

MC (2)007 Tuning

- Small correction on momenta: p  p (1+ O(10-4))

- Small smearing in three different Mpp2 regions

DATA & MC 2002

- Small Fine Calibration procedures seems to give a better DATA – MC agreement

- Tuning on MC seems to be much simpler than the 2001-2002 one

 mean value physical variables comparison  only small shift on MC value needed

 widths of physical variables comparison  bit smaller (with respect to BV) smearing

on MC needed

STATUS

- Study dedicated on 2002 Small Angle selection

- Maybe small further development on DATA Small Fine Calibration and MC 2002 Tunning	 However ready to be used

... TO BE DONE

- Further check on the effect on some physical quantities: W for Large Angle, qS , Mpp2

spectrum...

- Study for 2002 Large Angle and 2006

A second “practical” summary

3. Measurement of the Likelihood efficiency

- Already performed in B. Valeriani's PhD thesis

- Needed for Large Angle (.and. configuration) with high precision

- Obtained directly from DATA

p+p-p0

- kinematic fit c2 < 30

- Mpp2 < 0.5 GeV2

- Mtrk > 130 MeV

limited at high momenta

Two control samples

p+p-g

- | Mtrk – mp | < 2.5 MeV

- logrl(p+) > 2 for testing p-

- logrl(p-) > 2 for testing p+

limited at low momenta

Large momentum region overlap

- Very clean sample of p tracks

- Likelihood requires DCH track associated with EMC cluster (track velocity one of

the input): newextratom assiciation: TRASSOC

a) TWO KIND OF EFFICIENCIES

1. Intrinsic likelihood efficiency: eintr=

2. Intrinsic likelihood efficiency + TRASSOC efficiency:

etrassoc=

b)TWO STEPS

1. Efficiency in bins of momentum and polar angle

2. ppg MC  efficiency as function of Mpp2

Strategy

logrl>0|TRASSOC=.true.

any logrl|TRASSOC=.true.

logrl>0|TRASSOC=.true.

any logrl|(TRASSOC=.true. U TRASSOC=.true.)

Intrinsic likelihood efficiency eintr

p+p-g control sample

Intrinsic likelihood efficiency eintr

p+p-g

+

p+p-p0

Intrinsic likelihood + TRASSOC efficiency etrassoc

p+p-g

+

p+p-p0

Likelihood efficiency as function of Mpp2

- Likelihood efficiency table merging ppg and ppp samples:

ppp  p < 350 MeV and ppg  p > 350 MeV

- MC ppg, all the selection applied but logrl

- Look for each event at pi and qi of p+ and p-

- Take the corresponding likelihood efficiencies elik(,pi,qi)

- Generate 103 events with current kinematic taking into account the appropriate likelihood efficiency tables

 Store the likelihood efficiency as a function of Mpp2

To increase the precision: finer binning

 8 bins in polar angle [50-130]: bin width 5

 16 bins in momentum [100 MeV-500 MeV]: bin width 25 MeV

Intrinsic likelihood + TRASSOC efficiency etrassoc

Systematic studies

Check BhaBha residual contamination

ppg

- Enlarge | Mtrk – mp | < 2.5 MeV  | Mtrk – mp | < 5 MeV

- Hemisphere where e- (e+) contamination reduced

q(p+) > 90 for testing p+

q(p-) < 90 for testing p-

ppp

- Change systematically c2 cut: c2 < 15, c2 < 45

- Require second track to be identified as a pion

logrl(p+) > 2 for testing p-

logrl(p-) > 2 for testing p+

Result stable within 0.2% precision

Conclusion for Likelihood efficiency

& Outlook

- Likelihood efficiency and Track To Cluster association measured for 2002 DATA

ppp for low momenta and ppg for high momenta

- Large Angle Analysis (.and. configuration) up to 6% of inefficiency

- Excellent agreement between the two control samples

- Systematic for the efficiency 0.2%

- Efficiency as function of Mpp2 : deviation from B. Valeriani's for Mpp2 < 0.6 GeV2 up to 2% difference

- Still do be checked: Check the dependence of the efficiency on the initial Pion Form Factor in MC signal

Near future plan for Large Angle Analysis (2002 DATA)

- Background subtraction of irreducible f0(980) contribution

- FEVA code

- Fit to Charge Asymmetry using FEVA

- Common fit to Mass Spectrum and Charge Asymmetry

(Debora and Graziano)

- Fit procedure for reducible background contribution

- Detailed study on tracking calibration and MC tuning

- Dedicated fine tuning for MC 2002 at Large Angle

GOALS

- New value for the Pion Form Factor for EPS

- f0(980) contribution improvement

- other small refinements (for instance bkg.)

- Charge Asymmetry from PoP DATA

- testing the sQED for FSR impact for OnPeak DATA

Backup

Let's try to have some geometrical thoughts

1. Assume that p+z is over estimated

2. Two different condition ( q+ < 90 and q+ > 90 )

2.1 q+ < 90

 p+z + p-z > pbst  pmiss = pbst - (p+z + p-z) < 0

2.2 q+ > 90

 p+z + p-z < pbst  pmiss = pbst - (p+z + p-z) > 0

p+z

p-z

pz bst

z

p-z

p+z

pz bst

z

Look at the mean value of the Gaussian fit of the

pz miss vs q distributions...

... mean value of the Gaussian fit of the pz miss vs q distributions

q+ ()

q- ()

pz miss

pz miss

DATA 2002 Collinear Events

in the LAB system

DATA 2002

- pz miss trend as expected

- if perfect fine calibration pz miss(90) = 0.

But it is not  hint for a systematic shift on the z component

q+ ()

q- ()

pz miss

pz miss

DATA 2002

DATA 2002 Collinear Events

in the LAB system

After small shift on the z component of momenta

of pz (1  O(10-4))

The code of (2)007 MC tuning

*============================================*

SUBROUTINE PTUNE07(pxtra,pytra,pztra)

*============================================*

* 2007 2nd version

IMPLICIT NONE

INCLUDE ?

INCLUDE 'physqua.inc'

INTEGER idh, ii

REAL pxtra(2) ,pytra(2) ,pztra(2), pmod(2)

if (QQ.lt.0.5) then

do ii = 1, 2

pxtra(ii) = pxtra(ii) * (1. + 3.8E-4)

pytra(ii) = pytra(ii) * (1. + 3.8E-4)

pztra(ii) = pztra(ii) * (1. + 3.8E-4)

enddo

elseif (QQ.ge.0.5.and.QQ.lt.0.8) then

do ii = 1, 2

pxtra(ii) = pxtra(ii) * (1. + 2.5E-4)

pytra(ii) = pytra(ii) * (1. + 2.5E-4)

pztra(ii) = pztra(ii) * (1. + 2.5E-4)

enddo

elseif (QQ.ge.0.8.and.QQ) then

do ii = 1, 2

pxtra(ii) = pxtra(ii) * (1. + 3.E-4)

pytra(ii) = pytra(ii) * (1. + 3.E-4)

pztra(ii) = pztra(ii) * (1. + 3.E-4)

enddo

endif

999 continue

RETURN

END

*========*

MOMENTUM

CORRECTION

 Mtrk mean value

*===========================================*

SUBROUTINE PSMEA07(pxtra,pytra,pztra)

*===========================================*

C 2007 2nd version smearing

IMPLICIT NONE

INCLUDE ?

INCLUDE 'physqua.inc'

INTEGER ii

REAL ranlux, prescale, smear1, smear2

REAL pxtra(2) ,pytra(2) ,pztra(2), gau(2)

EXTERNAL ranlux

C INIZIALIZATION

call vzero(gau,2)

if (QQ.lt.0.7) then

call RNORMX(gau,2,RANLUX)

call ranmar(prescale,1)

if (prescale.lt.0.05) then

smear1 = 1. - gau(1)*0.005

else

smear1 = 1. - gau(1)*0.0015

endif

call ranmar(prescale,1)

if (prescale.lt.0.05) then

smear2 = 1. - gau(2)*0.005

else

smear2 = 1. - gau(2)*0.0015

endif

else

call RNORMX(gau,2,RANLUX)

call ranmar(prescale,1)

if (prescale.lt.0.05) then

smear1 = 1. - gau(1)*0.007

else

smear1 = 1. - gau(1)*0.0018

endif

call ranmar(prescale,1)

if (prescale.lt.0.05) then

smear2 = 1. - gau(2)*0.007

else

smear2 = 1. - gau(2)*0.0018

endif

endif

C Pi+

PXTRA(1) = pxtra(1)*smear1

PYTRA(1) = pytra(1)*smear1

PZTRA(1) = pztra(1)*smear1

C Pi-

PXTRA(2) = pxtra(2)*smear2

PYTRA(2) = pytra(2)*smear2

PZTRA(2) = pztra(2)*smear2

RETURN

END

*========*

MOMENTUM

CORRECTION

 Mtrk width

Control samples

p+p-p0

- kinematic fit c2 < 30

- Mpp2 < 0.5 GeV2

- Mtrk > 130 MeV

limited at high momenta

p+p-g

- | Mtrk – mp | < 2.5 MeV

- logrl(p+) > 2 for testing p-

- logrl(p-) > 2 for testing p+

limited at low momenta

LARGE MOMENTUM REGION OVERLAP

p+p-p0 control sample

Intrinsic likelihood + TRASSOC efficiency etrassoc

p+p-g control sample

p+p-p0 control sample

Comparison with B. Valeriani's intrinsic efficiency

2007-05-09T14:40:17