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1
KLOE _at_ DAFNE Computing and Network Maria Lorenza
Ferrer LNF-INFN Maria.Lorenza.Ferrer_at_lnf.infn.it
CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
2

• Physics at KLOE
• The KLOE detector
• DAQ and OFFLINE requirements
• Computing and Network
• Design Strategy
• Achievements
• Present Status
• Archiving
• Hardware and Software
• Present Status
• Database
• Software
• Present status

CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
3
8.5x109 KLKS 1.2x1010
KK- 106 f0
g,a0 g 2.5x108 , 2.5x106 hg, h g
At full Luminosity 5?1032 cm -2 s -1 in 1 Year
?
Measure all the relevant CP CPT violation
parameters from INTERFEROMETRY and DOUBLE ratio
?
Kaon form factors, Ks rare decay and Ks
semileptonic asimmetry (never measured)
?
Radiative f decay ? investigation of the f0 , a0
nature precise determination of BR(f? hg)/
BR(f? hg)

CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
4
The traditional way to measure direct CP
violation is through the double ratio R
16?(e?/e) where
I(l) decay intensity g(l-l?) experimental
resolution NKK Lint ? sfBR(f?KSKL)

• NKK etag drop out identically in the
  double ratio

_at_KLOE we are aiming for
d ? (e?/e) 10-4 dR few 10-4

CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
5
The goal for KLOE is to measure ?e?/e to 10-4
Since R ?16 ?e?/e ? 4?106 KL ? p0p0
events are required, corresponding, with KLOE
FVs and tags efficiencies to 2 years of
data taking _at_ L5?1032cm-2s-1 ? 4?1010f

CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
6
FIRST PHYSICS

• With a Luminosity L 5x1031 cm-2s-1
• Our first goal is to collect 100 pb-1 of data (
  3x108 F), which should allow the following
  physics results
  
• Measurement of ? (e?/e) to 10-3 statistical
  accuracy
• Measurement of K?3 form factors
• Meas. of BR(f ? f0g ? p0p0g) to ?5 better
  accuracy
• Confirmation of f ? a0g ? hp0g and
  measurement of
  its BR to ? 5 better accuracy.

Now 4x1030
CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
7
The KLOE Detector
KLOE Typical ee - general purpose detector 5 m
diameter 4 m length

• Beryllium Beam pipe (radius gt16 lS)
• Two Quadrupole triplets Calorimeters
  (32 PMs)
• Helium Drift Chamber (12,582 Sense Wires)
• Lead-Scintillating Fiber Calorimeter (4,880
  PMs)
• Superconducting Coil of 0.6 T

CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
8
The Electromagnetic Calorimeter

• Requirements
• ? Determine the vertex of KL,S neutral decays
  with an accuracy of few mm
• ? Have an high discriminant power on neutral
  modes K0?2p0 and K0?3p0
• ? Provide a fast and unbiased First Level
  Trigger
• ? Provide useful information for particle
  identification

Solution
Fine sampling lead/scintillating fibers
calorimeter
Volume Ratio FiberLead 5050 Energy sampling
fraction 13

• Good energy resolution (5 / Ö E (GeV) )
• Fully efficient in the range 20-300 MeV
• Excellent time resolution (70ps / Ö E (GeV) )
• Determination of g conversion point with 1cm
  accuracy
• Hermetic (rejection of 10-4 on KL 6g )
• Fast triggering response to suppress the 20 KHz
  Bhabha rate

CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
9
The Drift Chamber

• Requirements
• ? High and uniform track reconstruction
  efficiency
• ? Determine the KL,S vertex with an accuracy of
  200 mm x 1mm
• ? Good momentum resolution (dp/p? 0.5 ) for low
  momentum tracks
• ? Transparent to low energy g (down to 20 MeV)
  and KL,S regeneration

Solution

• High homogeneity, isotropy, large volume (f 4
  m, L3.3 m, 52140 wires).
• All Stereo layers with constant ?stereo drop
  1.5 cm, ? ? (60?150) mrad
• 12 layers of inner 2x2 cm2 cells ? 46 layers
  of outer 3x3 cm2 cells
• Helium (90He-10iC4H10 ) gas mixture
• Al(Ag) 80 mm field wires, W(Au) 25 mm sense
  wires, X0(gaswires)900 m
• Very thin walls mechanical structure entirely
  in C-fiber/epoxy ( ? 0.1 X0 )

CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
10
DAQ
DAQ handles 23000 FEE channels on 2.5 kHz f
5 kHz bckg

• Signal conversion/digitization in 2 ms
• Dead time 2.2 ms
• Bandwidth 50 Mbytes/s (5 Kbyte/ev.)
• Storage 200 Tbyte/y
  

Fully tested with peak rates of 10 kHz in
multibunches mode. Tested at maximum required
throughput using no zero suppressed calorimeter
data
Connection to offline world through a switched
Gbit/FastEther network
CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
11
KLOE Data Taking Short history
Apr 14th First collisions
Apr 14-May10 Stable data taking in single
bunch mode F line-shape scan (30 nb-1)
From May 10th collisions in multibunch mode
started. Few weeks of parasitic running (30 nb-1)
July 30th -Aug 8th our first period of
continuous data taking. data taking duty cycle
gt 95 !!
200 nb-1 collected
Parasitic running now

CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
12
ROOT

CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
13

• Acquire up to 50 MB/s (10 kHz) in about 1 hour
  runs (200 GB 100-200 files)
• Online monitoring for
• DA?NE conditions (beam shape, luminosity,
  background)
• Detector conditions (hot/dead channels,
  efficiencies)
• Need fast event selection and reconstruction of
  event samples
• 600 SpecInt95
• Archive raw data on tape but keep data on disk
  to allow for first reconstruction
• Disk space gt 10 TB
• Offline reconstruction at 10 kHz and concurrent
  re-processing /analysis
• Archive/recall bandwidth up to 200 MB/s, 6000
  SpecInt95
• Network
• Efficient TCP/IP transport
• Efficient access to remote disk (NFS)

CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
14

• Multi-platform environment
• Online
• in-house development starting from scratch (C)
  (no OO)
• experts people for initial design
• Offline
• in-house development (Fortran)
• CERN FERMILAB tool
• Archiving/Backup/HSM
• First tests on Legato/Fatmen/Shift
• ADSM adopted
• Database
• HepDB for calibrations constants
• IBM DB2 RDBMS for detector maps, run conditions,
  
• acquired /analyzed file status
• Move to commercial software when it exists at
  convenient price

CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
15

• lt 1997
• Online development using available CPUs for
  evaluation
• FDDI chosen for Detector and Online Farm
  interconnections (switch available)
• Online Offline development on multi-platform
  environment
• 1997
• CPUs in VME crates for detector readout
• 1/10 Online Farm
• 1998
• Full Online Computing power
• 1/10 Offline Computing power
• Tape Library 100 TB tapes
• Network switches
• 1999-2000
• Complete Offline Computing power, more tape
  drives, up to 1 PB (?) on tape

CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
16
gt General requirements about OS Compilers (a
given of Spec) gt Network capabilities gt
Reduced of nodes (no PCs) due to
- short manpower - high
reliability required to simplify management gt
Final choice according with -
technical constraints -
available expertise price
DEC ALPHA based for VME crates
IBM servers for Online
SUN servers for Disk serving and
Offline Xylan switches
for Networking IBM
library for Archiving
97 (7 servers)
98 (12 servers) installed in 99
All running now
Tapes ( 8 TB 5 TB, ESP in Nov)

CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
17
FDDI/Ether. Hubs
_at_ KLOE
Gbit and Fast Ether. switches
Xterminals _at_ Control room
Eth.
FDDI
Detector Readout Controls
Fast-Ethern.
Offline Farm
Gbit-Ethern.
Tape Disk servers
FDDI Switch
Eth.
FDDI
Gbit-Ethern.
Fast-Ethern.
Run Control Slow Control servers
Online Farm
_at_ Computing room
LNF Network

CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
18
SET
DETECTED
Duplex Mode
Auto- negotiate
Line Speed
Duplex Mode
Line Speed
Slot/ Intf
Xylan 1
3/ 1 enabled 100
FULL-D auto auto
SUN 3/13 disabled 10
HALF-D 10 half-d
NCD Xterm 3/25 enabled
100 FULL-D auto auto
TEK Xterm 4/ 1 enabled
1000 FULL-D 1000
full-d SUN 5/ 1 disabled
1000 FULL-D 1000
full-d IBM 5/ 2 disabled
1000 FULL-D 1000
full-d 6/ 1 disabled
100 FULL-D 100 full-d
IBM
Xylan 2
2/ 1 disabled 1000
FULL-D 1000 full-d 2/ 2
disabled 1000 FULL-D
1000 full-d IBM 3/ 1
disabled 100 FULL-D
100 full-d DEC

CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
19
26 can be installed
KLOE IBM 3494 Tape Library with 5,500
slots redundancy, high reliability, 6 (gt12)
drives 3590E 20 (gt40) GB
Up to 30 MB/s disk ltgt tape each server
Two servers 1/2 library each
H50 4-way 1GB 72GBdisk
H50 4-way 1GB 72GBdisk
Switched Gbit-Ethernet
-
Recalled areas NFS v3 exported
Up to 9 MB/s disk ltgt tape
SUN3500 2-way 1GB
SUN3500 2-way 1GB
SUN 500GB
Working areas NFS v3 exported
Offline Farm
Online Farm 350 GB
Switched Fast Ethernet

CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
20
KLOE IBM 3494 Tape Library with 5,500
slots redundancy, high reliability, 6 (gt12)
drives 3590E 20 (gt40) GB
H50 4-way 1GB 72GBdisk
H50 4-way 1GB 72GBdisk
HSM run DA?NE conditions
Scheduled ADSM backup
Online backup
using ADSM policies
RUN server
DB server standby
DB server active
FARM ADSM clients
Mirrored OS Database

CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
21
KLOE IBM 3494 Tape Library with 5,500
slots redundancy, high reliability, 6 (gt12)
drives 3590E 20 (gt40) GB
Import from node (2)
11.5 MB/s
H50 4-way 1GB 72GBdisk
H50 4-way 1GB 72GBdisk
Two phases
Switched Fast-Ethernet
Using server-to-server connection
Migration of 11,000 files (1600 GB) in 60.5
hours ltgt 7.3 MB/s
F50 4-ways
Export to node (1)
LNF IBM 3494 Tape Library with 220 slots 2
drives 3590 10 GB

CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
22

• DAQ configuration

• run conditions

• acquisition electronics
• configuration

• run logger
• general description of runs

• mapping between
• detector DAQ
• channels

• file logger
• description attributes of raw
• reconstructed data files

gt granularity at run level

• slow control logger
• detector and DA?NE
• parameters

2.5 KB/ run
gt several rows per run

CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
23

• IBM DB2 RDBMS

• very well supported in multiplatform environment

• well interfaced with ADSM

• dedicated tools

• simple client-server protocol
• multithreaded (up to 256 concurrent connections)
• based on SQL commands

• preferred over DB2 client-server solution

• less resources administration needed

• more efficient using caches on server

CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
24
Offline farm
Tape Library/recalled areas
VME-ROCK
Rec file
Datarec
DB
Collector
Raw file
VME
Recorder
DB
Sender
L3 filter
Raw file
Receiver
Calib
Builder
Recorder
Online farm

CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
25
TCL/TK

CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
26

CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
27
ARCHIVING RECALLING FILES - the KLOE HSM

• Raw reconstructed data files are archived by
  dedicated daemons
• when closed
• ONLY if they are declared in the Database

• Files in use are marked in the Database

• Files are deleted from disk by dedicated daemons
  
• disk space is required
• not in use but already analyzed, ...

• Files analyzed with a given program version
  can not been
• re-archived (program version should change)

recall raw s11 1 (run_nr between 9601 and 9605)
and (stream_code L3BHA) and () .
CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
28
List_runs -disk tail 20
List_raws 9859

CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
29
Using ADSM -API specialized daemons on ADSM and
DB2 servers.
Offline servers
Reconst.
Automatically archived
recalled
Retrieved at request
User area
Backup vs HSM
In progress
Resident daemon for disk space management
Online servers
Reconst.
Automatically archived
Raw files
From DAQ filters
Run slow DA?NE controls
History files.
HSM

CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
30
Conclusions
We have successfully tested

• Our detector performances
• Our trigger and DAQ reliability
• Our online monitoring
• Our archiving/backup/HSM Database systems
• Our reconstruction and filtering procedures

• Using powerful CPU servers that offer high
  reliability at relatively low cost
• short manpower but gt 1700 SpecFp95 running
• Data reconstructed at 3-4 kHz
• Stable high bandwidth network
• Commercial software for Tape library management
  and Database
• NIM software for IBM software installation,
  in-house utilities for system and production
  management

CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
31
??? ? ???? ? pp- ???
Candidate
M? 498 MeV
M?908 MeV
E?
57 MeV
32
The Electromagnetic Calorimeter Time performances
s(mip) ? 300 ps

Outside?Inside Inside ? Outside muon nicely
recognized (used to rejet comsic rays)
Outgoing m
T5
5 4 3 2 1
Ingoing m
T1
T1
T1-T5 (ns)
b
T1
b L/(T1-T2)
T1
Fit b vs p distribution Check the m mass
L
T2
p (MeV/c) (DC)
CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
33
The Drift Chamber Performances on bhabha and F
Bhabha momentum resolution
Ks???-
s 1 MeV
s/ P 0.4
Mks(MeV)
CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
34
DAFNE Design strategy
LDAFNE 5?1032 cm -2 s -1

• L VEPP-2M 5?1030 cm-2 s-1
• conservative single bunch approach
• L0 (single bunch) L VEPP-2M
• but large number of bunches
• L DAFNE nbunches ? L0

nbunches? 120 Þ Two Separate Rings

CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)
35
QCAL
Instrumenting the Quads improves the rejection of
KL? p0p0p0 by a factor of 5
Timing has been set. It helps to reject machine
background
CERN HEP-CCC Nov 1299
Maria
Lorenza Ferrer (LNF-INFN)