Bill Atwood, SCIPP/UCSC, Jan. 30, 2006 GLASTGLAST1

Closer to Reality

From Last Talk ( 7-Jan-06) – things seemed Great! However ...

1) In estimating the SRD I use the normalized (true) Extra Galactic Diff Rate instead of our absolute(meas.) rate... Iissue: the acceptance (Aeff) falls off at lower energies (there's almost a factor of 3 here) 2) Our intend operational mode is "Rocking" exposing our backside Issue: Large gaps between CalModules (there's another factor of ~ 1.3 here)

This analysis: Input: 1) First day of 5B Bkg. Run: dataset v7r3p5 (Includes rocking) 2) Extra Galactic Diff: dataset v7r3p5 3) All Gamma rep-V7r3p4 dataset, runs 401-800

All these datasets are "CTnew" mean application of the cuts shown by Julie prior to download

Bill Atwood, SCIPP/UCSC, Jan. 30, 2006 GLASTGLAST2

Input:CTnew FT1ZenithAngle > 100

High Energy e- Filter

Scrambled Tkr Filter

Heavy Ion Filter

.0

.3.4

.5.65

.75

SRD

1:1

Background and Diffuse Integral Rates

100

200

500

1000

2000

5000

10000

Emin

CTBGAM

CTBCORE > .1 && CTBBestEnergyProb .1

Base Class 1: CTBGAM > .35

Base Class 3: CTBGAM > .55

see next chart for Filter Definitions

Bill Atwood, SCIPP/UCSC, Jan. 30, 2006 GLASTGLAST3

((min(abs(Tkr1XDir),abs(Tkr1YDir)) < .01 & Tkr1DieEdge < 10 & AcdActiveDist3D > 0 & AcdActDistTileEnergy > .2) |(Tkr1SSDVeto < 7 & AcdActiveDist3D > -3 & AcdActDistTileEnergy > .15) |( AcdActiveDist3D >(-30 + 30*(Tkr1FirstLayer-2))) ) & CTBBestEnergy > 5000

Hi Energy e- Filter:

Heavy Ion Filter:

CTBBestEnergy > 5000 & ((CalTransRms - 1.5*Tkr1ToTTrAve) < 5)

(Tkr1FirstLayer - Tkr2FirstLayer) < 0 & Tkr2FirstLayer > 4 & Tkr2TkrHDoca > 100

Scrambled Track Filter:

Cosmic Proton:

Tkr1FirstLayer < 6 & AcdActiveDist3D > -80 & ((AcdActDistTileEnergy + AcdActiveDist3D/100) > 1)

Bill Atwood, SCIPP/UCSC, Jan. 30, 2006 GLASTGLAST4

Base Class 3: CTBCORE > .35 && CTBBestEnergyProb > .35

Same Contours as before

Base Class 3: CTBGAM > .50

Bill Atwood, SCIPP/UCSC, Jan. 30, 2006 GLASTGLAST5

On Axis

Aeff x FoV

Base Class 3 Cuts

THIS ONE

Bill Atwood, SCIPP/UCSC, Jan. 30, 2006 GLASTGLAST6

Bkg.

Diffuse

Base Class 3 Cuts

Bill Atwood, SCIPP/UCSC, Jan. 30, 2006 GLASTGLAST7

Hadronic Res. Bkg.

QED Res. Bkg.

100-500 MeV

500-2500 MeV

2500-12500 MeV

> 12500 MeV

Residual Background Broken out by Sources and CTBBestEnergy

Irreducible: e+ Conversions

Cosmic (Hi E) e-

Cosmic Protons – ACD Leakage?

Same energy bins as above

Correlated 's!

Bill Atwood, SCIPP/UCSC, Jan. 30, 2006 GLASTGLAST8

ACD Leakage

Correlated Events: McDirErr < .1

and not e+ McId != -1

72 events Side Ribbons don't go to top!

Estimate 47 events are leaked in this way

These are the TopCorner Leakers found in the hand-scan

Require events start in Top Layer Tkr1Z0 > 590

Composition:

Bill Atwood, SCIPP/UCSC, Jan. 30, 2006 GLASTGLAST9

Project Tracks to + Const. X Sides and fold to YSide > 0:YSide = min(abs(Tkr1Y0 - abs( (832-abs(Tkr1X0))/Tkr1XDir) * Tkr1YDir), 742)ZSide = min(abs(Tkr1Z0 - abs( (832-abs(Tkr1X0))/Tkr1XDir) * Tkr1ZDir), 800)

All Data Data Inside Holes

All Gamma Ineff. = 90/105090 = .1%

Bill Atwood, SCIPP/UCSC, Jan. 30, 2006 GLASTGLAST10

Suspect the same is true on Const. Y Sides – Evidence poor –

Const. X Sides Holes Removed

Both Sides Holes Removed

Difference

Combined: BKG: 209 DIFF: 63 GAM: 220

Bill Atwood, SCIPP/UCSC, Jan. 30, 2006 GLASTGLAST11

Remaining Base Class 3 Residuals

Hadronic QED

Next step: separate out the CTBBestEnergy > 1 GeV and hand scan

69 Events after X,Y Side Holes

Bill Atwood, SCIPP/UCSC, Jan. 30, 2006 GLASTGLAST12

P Primary12.17GeVTracking error in Y

e+ Back-Entering1.71GeVShower Stub inTracker

Uncorrelated Events

Bill Atwood, SCIPP/UCSC, Jan. 30, 2006 GLASTGLAST13

P Primary32.55 GeVAcd TileMcPosHit 49KeVRibbon Slot (10 of these)

P Primary4..494GeVAcd TileMcPosHit 1.57 MeVNo ACD Digi

Correlated Events

Bill Atwood, SCIPP/UCSC, Jan. 30, 2006 GLASTGLAST14

e- cosmic6.65 GeVRibbon Ineff.

And so on...

Bill Atwood, SCIPP/UCSC, Jan. 30, 2006 GLASTGLAST15

Speculation: We may be able to kill most(all) of the Correlated Bkg. > 1 GeV If so where will we be -

Present Status Corr. Bkgs. Removed

Goal

= 35 events

Bill Atwood, SCIPP/UCSC, Jan. 30, 2006 GLASTGLAST16

Top Ribbon Ineff.

And... 45% Already There:

16 of these events are CTBBestEnergy > 1 GeV

Req. CTBBestZ0 > 590 (Starts at the Top) & McDirErr < .1 (Correlated Event)

This will be an issueon the sides as well

Need DOCA to nearest Ribbonwhether or not it was hit....

69 Events Total (out of 365)