Offline Status Report

M. Moulson, 27 Feb 2001

Summary presentation for KLOE General Meeting

Outline:

• Processing of 2000 data

• Upcoming developments for datarec executable

• Status of MC production

• Ntuples/DST’s: status and proposals

Processing of fall 2000 data

Reference data set: Runs 15197—17330 (23 Sep—11 Dec)5.61G triggers, 15543 files, 13.6 TB raw data

Offline L dt = 23.1 pb-1

• DBV-6: 5.5 pb-1

• DBV-7: 18.0 pb-1

Total events collected:

• 130M Bhabhas

• 67M decays est. = 2.9 b

• 10.9M KL tags

• 7.2M KL crash

• 19.5M KK w/ vertex

• 6.2M tags

Processing statistics for fall 2000 data

Raw data: 5605M Events, 13.6 TB

Physics: 2.0% of total events25% of raw volume160 GB/pb-1

Bhabhas: 2.3% of total events20% of raw volume114 GB/pb-1

Stream Events (M) Volume (GB) Summarykpm

ksl

rpi

rad

clb

19

64

6

23

1

687

2270

166

520

19

112M Events

3.6 TB

bha 127 2623flt

afl

cos

1248

31

96

3791

92

273

1379M Events

4.2 TB

Avg. fraction ofevents tracked:

26%

Avg. bandwidth on 40 CPU’s: 1060 Hz

Avg. time/trigger

38 ms

Avg. time/tracked evt.

151 ms

datarec performance in fall 2000Daily averages

Average uptime efficiency: 63%Staging and procedural losses count

Evts. acquired Evts. processed

Once in stable situation, able to follow with ~75% of data processed

No

DC

trig

End

of

data

Fol

low

-up

Aft

er X

mas

Mis

sed

runs

Rep

roce

ssin

g

Acquistion rateReconstruction rate

Farm bandwidth

23 Sep 11 Dec

Data processing: Issues to discussIntended to give feeling

Not an exhaustive list

More detail at review

Reprocess DBV-6 (5.5 pb-1) for neutral radiatives?

FILFO Bhabha filter deleteriousRejects 40% of events

Only runs on “charged” eventsPre DBV-7: Charged event: Nhits > 30Pileup contribution to Nhits in 2000 data

DBV-7: Bhabha filter vetoed by neutral radiative tag instead of Nhits cut

Luminosity to 1% only possible with DBV-7 reconstruction

Streaming-related issues:

flt stream (raw)About 30% of raw volume (3.8 TB in 2000)Apparently never used

selcos cosmics10% written as raw, also processedIncrease statistics in raw, don’t processIncrease number processed, don’t write raw?

Reprocess runs processed before final EmC calibrations available?

Currently we do not wait for calibrations before reconstructing

Complete EmC reconstruction is performed before Ntuple/DST production

Ntuples/DST’s, YBOS out of phase

Effects on streaming are permanent

Next version of datarec executable

Already in DBV-8:

CLUFIXENE MC events, scale factor

EMCALIB slewing corrections

VTXFIN corrected path length calculation

TRCLMOD modified projection from track to cluster

Ready for inclusion in datarec:

FILFO fast tracking cuts, Nhits definition

VLAB new luminosity module

A_C zlib event compression

MC: f events

Before scale corr.

After scale corr.

CLUFIXENEHow it works:

• loop over “missing” cells• attenuation length correction from zcl

• sum EA and/or EB into cluster

fscale because ABSCAL done w/o CLUFIXENE

Problems:• CWRK not updated for missing cells• Ecorr Ecl – Ecl

bef not saved in bank stream

• Makes fscale necessaryABSCAL uses CWRK

New developments:• CLUFIXENE now works for MC events

• fscale off by 2%—adjusted

scalemiss cellbefclcl fEEE

In progress:• Bookkeeping mechanism to replace CWRK

CSPS bank includes missing cells • ABSCAL will run on CSPS

Remove scale factor

EMCALIB: Slewing corrections

TcorrA,B = TA,B – T0

A,B – TslewA,B

TslewA,B = Const/(EA,B)0.1

• Empirical prescription, same for all cells

• Tested on “old” data with T0’s adjusted by hand

• Correction now applied in T0ALIG and TIMCAL

• Disabled in code for runs < 17606

Diagnostics:•T1T5 distributions OK

•v12 distributions OK

•FILFO should not be affected

T5

T1

v12

Slewing correction now applied cell-by-cellee evts. w/w/o slewing correction

ps 140)GeV(

ps 60

ETT

CLUREC: New clustering cuts

Most split clusters are actually unmerged clusters

Basic problems:• Current cuts do not depend on Ecl

• Complications from shower fragments

Problem of unmerged clusters has been comprehensively studied

ee SM + LF

CD

f SG

KSKLKSKLcrash GC

KSKLKSKL MC

r, r, z 6 cm/E(GeV)

t 3.5 ns

Attempt to tune CLUREC cuts to minimize cluster splitting

t 2.5 ns

z 30 cm

r 20 cm All four conditions must be met

r 40 cm

Clusters are merged if:

Proposed new merging criteria:

Status:Performance gains to be evaluatedImplementation easy

0.8

1.0

1.2

100 200 300 MeV

Cluster efficiency studies

e

e

From ee events:• Good vertex, 2 tracks,

high p

• p1, p2 > 490 MeV• Exclusion region around

e± clusters• pmiss(DC) gives direction

of expected • Systematic from cone

definition• Studied in data, MC

From events:• Good vertex, 2 tracks• pmiss(DC) = p

• 1 direction gives expected E1

• Compatible 1 identified direction of 2

• Systematic from cone definition• Advantages:

higher pmiss(DC)smaller systematic with , E

MC Data

MCData

Tail normalized

recMC

recdatareccell EN

ENER

Ecell (MeV)

from ee evts. with thresh. simulation

MC Data

Cluster efficiency: Data and MCSimulation of cell thresholds

MC: • Only when no p.e. after attenuation

simulated at one side• Relatively hard cutoff at ~2 MeV

Real life:• Roll-off, characteristic value ~7 MeV

Compare MC to data using ee eventsErec for all cells associated to clusters

on barrel, Ecl > 200 MeVsimilar shape on endcaps

A_C module EMCFAKETHR:• Deletes CELE hits from MC events according to

hit-or-miss sampling of Rcell

• Brings (E) for data and MC into agreement for high

• Some systematics to be studied:+1 MeV offset in Erec

MC to obtain good results

• Ultimately hope to avoid having to map Emethod

to EKINE when applying corrections

Status: almost ready for release

EmC data structuresCTRG: Sector cluster correspondence bank

Combines information from PZZA, TELE banks• Number/kind of sectors not connected to clusters• For all clusters: indices/kind of sectors incorporated• Can also obtain indices of clusters in each sector

Status: done, also in PROD2NTU

CSPS: Calorimeter space-point bankCombines information from

• CELE: EA, EB, TA, TB

• CWRK: (E, X, Y, Z, T)cell

into one compact structure, capable of storing multiple hits per cellStatus: development, almost ready

CLUS: Compact cluster bankAnalogous to CSPSStatus: ideation

FILFO: Cuts and DC noise

FILFO cuts on number of DC hits (Nhits)

Cosmic rejection:• By crossing speed, shower depth cuts for Nhits < 175• By ring cuts for 0 < Nhits < 60• Cosmics discriminated from KK events by Nhits < 100

under certain conditions

MB rejection: • MB events have Nhits < 200• Min EmC energy vs. Nclust for neutral events (Nhits < 50)

Noise hits in DC create interferenceHot channels masked in RAW2DTCE

Problem from diffuse component of noise• Does not depend on detector• Can be estimated from Nhits(t < 0)

Nhits(adjusted) = Nhits(raw) – Nfake

measured estimated

0 t

Nh i

ts

Status: RAW2DTCE already modifiedFILFO modification trivialGains under study

FILFO: Fast trackingEmC reconstruction

t0 step zero

ATFMOD/VTXFINpar = 1

FILFO

FILFOTRK

ATFMOD/VTXFINpar = 4

ATFMOD/VTXFINpar = 3

Event Classification

.bhaxxx

RAW

Mach. Bkg.Cosmics

Single trackevents

UFO’s

Physicsstreams

Bhabhastream

Modifications to ATFMODAdded parameter suppresses:

• Hit addition/rejection• Kink finding• Multiple scattering• Number of iterations during refitting

Similar procedure used for Bhabhas

Reduces reconstruction time 4—5

New module: FILFOTRKRejection based on preliminary tracks

• Currently implemented:Single track events

• Eventually:Inclusive cuts based onevent selection algorithms

Status: Code structure completeGains fully realized with new rejection criteriaPossible to jump-start tracking?

VTXFIN: Path length calculationErrors fixed in calculation of track length from FH/LH to vertex

Vertex position not affected

2

1Relative to analytic (helix) calculation:Should have some tails

Stepping error (1)Avg. effect: 2.5 cm (modularity: 5 cm)

Numerical extrapolation of trackUses B, takes into account dE/dx5 cm step size (except last step)

For L, vertex was put at beginning/end of step because calculation was incorrectly started from FH LH

Endpoint error (2)Avg. effect: 20 cm

Vertices b/t BP and DCTracks which intersect BP

Both fixed in DBV-7

Function vtxswm_p2nAnalytic calculation of L

Works with PROD2NTU

BP

DC20 cm

OK

TRCLMOD: Recent developments1. Track length from LH to EmC systematically overestimated by 2cm

Pre DBV-8: Can simply subtract 2 cm from this lengthOften canceled with –2.5 cm error in VTXFIN track length (hard to detect!)

2. Changes in calculation of association

EmC

OLD

NEW Old cuts:, z (barrel)x, y (ecaps)

New cut:Distance

Cuts are large—does not have a large effect except for case of large angle of incidence

3. Talk-to option to force TCA for tracks that end at vertex

TCA usually inhibited—idea is to follow “tree”

May recover cases involving split tracks

Not default behaviorContemplate use in KS semileptonic analysis in order to get better control over TCA efficiency

Luminosity measurement in 2000Traditional offline L estimate from LAB’s:

• 2 clusters with 45° < < 135°• 300 < E < 600 MeV• Acollinearity in < 10°• In time within 4 ns• Acollinearity in < 80°

Problems:• separation: 50 hits in DC

Up to 8% background from ’sesp. at beginning of 2000 running

• Emax cut unstable w.r.t. energy calibration(E) = 42 MeV at E = 510 MeV3% effect

On-the-fly fixes in 2000:• Exclusive 3D acollinearity cut to

eliminate ’s • Emax 600 800 MeV

3dim - Accolinearity3dim - Accolinearity21

21cosClCl

ClCl

xx

xx

)( eeee

)(ee

New Version of BABAYAGA !

cos > -0.975

1%

VLAB luminosity measurementStarting sample: FILFO LAB’s

with 2000 cut revisions

Event selection:2 tracks from IP with opposite chargerxy < 7.5 cm, rz < 15 cmDistance between 1st hits > 50 cm

VLAB cuts:55° < (cl) < 125°Acollinearity in < 9°400 MeV < E(tr) < 600 MeV

MC effective cross section = 421 nb0.3% background from events manually subtracted

New L estimate from events (GGL)FILFO LAB cutsCut on Nhits vs. 3D acollinearityMC effective cross section = 118 nb

GEANFIBABAYAGA

Data

E + -

+ -

VLAB status

VLAB routine is well tested and performs as expected

• estimated systematic effects from cuts on E, : L/L < 2%• best-tested and most accurate luminosity measurement yet

VLAB has been implemented in an Analysis Control module• all relevant parameters accessible via Talk_To

• will be inserted in next datarec version

• long term method test by comparison to Gold Bhabhas, LAB’s, and GGL

Number of VLAB candidates to be written to DB on a file-by-file basis• statistical accuracy for a single run: 30 nb-1 L/L= 0.9 %

Plan to process DBV-7 bha stream to produce luminosity map (17 pb-1)

• Pre DBV-7 executable had Emax(cl) = 600 MeV cut LAB sample biased

New version of GEANFIGEANFI version 1.06/07 released on 6 February:• EVA generator inserted

generator with different models for ISR, FSR, interference with f0• decay inserted• decay (C-violating) inserted• Improved simulation of K 3 decays generator

added parameter to specify fraction of decays that don’t proceed via • Modifications to GEANT tracking to allow generation of specific KL topologies

KL decays in beam pipebefore entering DCbefore entering calorimeterin calorimeter

• Change name of output banks: DTCE MDTC, CELE MCELMakes it easier to re-reconstruct MC files that have already been reconstructed

• New default value for magnetic field: I = 2300 A

Modified MC banks and analysis chain

RAW2CELE/RAW2DTCE

All other reconstruction

TSKT/SMEAR_T0

T0_FIND/CLUFIXTIM/T0_MENO

EMCALIB/CLUREC/CLUFIXENE

mcr

mco MCELMDTC

CELE DTCE

Smeared banks

Corrected banks

MC

EL

, MD

TC

RAW2CELE/RAW2DTCE

All other reconstruction

T0_FIND/CLUFIXTIM/T0_MENO

EMCALIB/CLUREC/CLUFIXENE

xxx

raw CALRDCHR

CELE DTCE

Corrected banks

CA

LR

, DC

HR

MC Data

• New names for MC output banks:CELE MCEL, DTCE MDTCPristine banks for re-reconstruction

• New A_C path for MC reconstruction:

use (dmapload) emcdbini raw2cele dcdbini raw2dtce (tskt smear_t0) emcalib clurec clufixene t0_find clufixtim t0_meno filfo dconvr…

• For MC versions 167 and later• Re-reconstruction w/w/o redoing

trigger simulation/t0-smearing OK

• For MC versions pre-167:

• Original trigger simulation/smearing automatically used

• Re-reconstruction w/ new trigger simulation/t0 smearing not possible

• New routine to obtain MC versionGET_MC_VERSION(VERSION)

Status of MC production

Event type Request 26 Feb

all 2.4M 2.4M

KSKL

KS ; KL various

KS ; KL all (1.1M)

2.9M 1.3M

KK

K ,e0.24M 0

radiative channels,,fa

ee

2.0M 1.7M

calibration channelseeee

ee

cosmic rays

0.8M 0

Total ~8.3M 5.4M

Production details:

New GEANFI version (1.06/07)

New datarec version (DBV-8)

8 offline nodes (fsun03-10)

Environment similar to datarec

Output:

Reconstructed YBOS files (.mcr) archived to tape

Program:

Continue with MC production until farm bandwidth needed to reconstruct new data

9 days at current rate

MC production for 2000 data started 9 Feb

Ntuple production for ksl streamStarts from ksl stream

• EmC reconstruction• t0 find (step 1)• PROD2NTU ksl Ntuples• ksl Ntuples split into substreams• YBOS output for KL events• manual tape backup

Ntuple Tags

kslall events in ksl stream

ks2piKS

KS (gold)

klcr KL crash

ksemilKS semileptonic decays

kl3p0 KL

klppp KL

intertag interferometry tags

Status:

About 4 pb-1 processed in Jan

23 GB of Ntuples!• Eliminated KS tag• Dropped DPRS block• TELE, PIZZA blocks condensed

into C2TRG

Restarted 19 Feb, immediately stopped • Initially for machine problems• Fine-tuning of scripts, output file

sizes• 30-50% reduction in data volume

Restarted this weekend, 1 pb-1 processed

DST production for radiative streamStarts from rad stream

• EmC reconstruction

• t0 find (step 1 radiative)

• Retracking for events that overlap with bha stream

• YBOS DST’s:

• 4 substreams for analyses in progress

• Subset of events in rad stream

E.g., ee, events

• Reduced bank set

• Manual tape backup

• Diagnostic Ntuples for some substreams

Output stream Topologies

neu_max4gneutral events, at most 4 prompt ’s

neu_min5gneutral events, 5 or more prompt ’s

cha_min3g2 tracks3 or more prompt ’s

cha_ppg tagged events

Diagnostic Ntuples:Allow estimates of events/nb-1

Status:

•All data reconstructed with DBV-7 completed

•Total size of all YBOS output: 40GB circa

Outlook for mini-DST production

Proposed format for mini-DST’s

•zlib-compressed YBOS

•Bank subset essential for physics analysis

•Summary banks?

•Substreams?

Phase 1:

Mini-DST production in dedicated pass

Phase 2:

Mini-DST production as part of data processing

Phase 1 Status:

Compression DoneScripts Some work neededRetained banks Needs definitionSummary banks Needs definition, codingSubstreaming Needs definition

Waiting on physics inputTechnical aspects relatively simple

Phase 2 Outlook: More distantTechnically more complicated

E.g.: what to do when files from a given run processed weeks apart?

Solutions exist, but limited resources to devote(man and machine)