Transcript The KLOE computing environment

DaFne upgrade
(as seen by a KLOE member)
G. Venanzoni – INFN/Frascati
International Workshop on e+ e- collision from Phi to Psi
Novosibirsk, 27 Feb – 2 Mar 2006
Outline:
Status of DAFNE
Upgrade of DAFNE:
 Short term project
 Long term project
Physics program at DAFNE-2
Upgrade of the detector
Conclusion
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
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DAFNE e+e- machine at Frascati (Rome)
KLOE detector
e+
e
FINUDA detector
• e+e  f s ~ mf = 1019.4 MeV
• beams cross at an angle of 12.5 mrad
• LAB momentum pf ~ 13 MeV/c
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
BR’s for selected
f decays
K+K-
49.1%
KSKL
34.1%
rp +p+pp0
15.5%
3
DAFNE performance up to Dec 2005
Peak Luminosity
1.4 x 1032 cm2s1
2
Off peak
run
Day performance: 7-8 pb-1
Integrated Luminosity
Best month L dt ~ 200 pb1
Total KLOE L dt ~ 2400 pb1
(2001,02,04,05)
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
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DAFNE 24h Performance (Dec. 05)
1.2e-32
ee+
2A
1A
8 pb-1
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
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Machine energy stability
2004
s monitored to within 70 keV
Some variations in 2004
Stable (1019.3-1019.6) in 2005
2005
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
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DaFne Upgrade – short term (3 years)
Starting from 1.51032, 2fb-1/year:

Reduction of e- ring beam impedance (by a factor 2) :


Removal and shielding of the broken Ion-Cleaning-Electrodes
Higher positron current (up to 2 A), so far limited to 1.3 A:

New injection kickers

Ti-Coating against electron cloud

Feedback upgrades

Wigglers modifications to increase Lifetime (by a factor 2):

New interaction region

Transfer lines upgrade (continuous injection)
To be discussed:

Crab cavities, waist modulation (RF quads)
Final luminosity 3 times higher?
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
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DAFNE-2: Long term upgrade (2010)
also for high energy program (up to 2.4 GeV)

Change of machine layout, insertion of:
- Superconducting cavities
- Superconducting wigglers
- Ramping Dipoles
- New vacuum chamber
Energy (cm) (GeV)
1.02
Integrated Luminosity per year (fbarn-1)
>10
Total integrated luminosity (5 years, fbarn-1)
Peak luminosity (cm-1sec-2)
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
2.4
>50
>3
>8 1032
>1032
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TDR in preparation: necessary to submit the project
IR
DAFNE 2 layout
Wigglers
rf
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
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Physics at DAFNE-2
See presentation of M. Testa

Kaon Physics (including test of QM with interferometry)

(Multi)hadronic cross section up to 2.4 GeV
See presentation of S. Eidelman

Spectroscopy (vector mesons)

gg physics

Time-like form factors (baryons and mesons)

Radiative f decays

Kaonic Nuclei
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
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TOTAL CROSS SECTION R
Radiative
return
Energy
Scan
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
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1)
Most recent inclusive
measurements:
MEA and B antiB,
with total integrated luminosity of
Lint (nb-1)
Impact of DAFNE-2 on inclusive measurement
o
20 pb-1
MEA, 14 points, Lett. Nuovo Cim.30 (1981) 65
• B antiB, 19 points, Phys.Lett.B91 (1980) 155
200 nb-1 (one hour of data taking at
1032 cm-2 sec-1).10% stat.+ 15%
syst. Errors
s (GeV)
2) With 20 pb-1 per energy point (1year
of data taking at 1032 cm-2 sec-1 ) a
precise comparison exclusive vs.
inclusive can be carried out
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
s (GeV) 12
Impact of DAFNE-2 on exclusive channels in
the range [1-2] GeV with a scan (Statistical only)
3p
BaBar, with the published Lint per
point (90 fb-1)
BaBar, with 10  (the present Lint )
DAFNE-2, with 20 pb-1 per point
2K2p
• DAFNE-2 is statistically
better than O(1ab-1) B-factories
4p
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
• Improvement on systematics
come as well
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Impact of DAFNE-2 on the range [1-2] GeV
using ISR @ 2.4 GeV (Statistical only)
BaBar, with the published Lint per point (90 fb-1)
BaBar, with 10  (the present Lint )
comparison among the present
3p
BaBar analysis, an (O(1 ab-1)) BaBar
update, and Lint = 2 fb-1 at 2.4
GeVper energy point @ DAFNE-2
statistical
dshad / shad (%)
DAFNE-2, with 2 fb-1 @ 2.4 GeV
• No much improvement
respects to B-factories
s (GeV)
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
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gg Physics at DAFNE-2
gg P [p0 , h , h’]  G(Pgg)
gg p0p0 , p+p , hp, hpp  G(Sgg) / test of ChPT
 h’, f0(980), a0(980) needs
√s > Mf
 At f peak an e+/- tagger is
needed (background).
News:
 KLOE run off-peak:
“test run” for gg physics
Renewed interest for
per gg  p0p0 at threshold
 DAFNE-2  higher √s
Ggg di f0 e a0
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
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Search for s [ f0(600) ] in gg  p0p0
 G(s gg)×G(s pp) sensitive to quark structure (4q vs. 2q)
 Which √s ? 1 GeV ok (Off f peak)
 More information from KLOE test run
BELLE
f0(980)
f2(1270)
gg  p+p
p0p0
Only data available gg 
[Crystal Ball @ DORIS 1990]
Efficiency cut
Wgg>0.7 GeV
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
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Time-like form factors
Threshold for Baryons (GeV)
(1) From s(e+e-  NN)  |G|2
4p 
s
3s
p
1.876
n
1.879
L
2.231
Np (pp- , np0)
S+
2.378
Np (pp0 , np+)
S0
2.385
Lg
2
S
2.395
Np
D
2.464
Np
X0
2.630
Lp0
X
2.643
Lp-
(np-)
2M


(
)
(
)
G
s
+
G
s


s
2
2
2
N
M
E
(2) From the angular distribution
 |GE|/|GM|
4M N2
ds  2 C 
2
2
2
2 
(
)
(
)

G
s
1
+
cos

+
G
s
sin

E
 M
d
4s 
s

(
)
(3) From the polarization
 F(q2) =fE - fM
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
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Existing data
Proton data - type (1)
Ipothesis GE=GM
Proton data:
|GE|/|GM| - type (2)
Neutron: only FENICE (500 nb-1,
~75 evts signal)
No data available on polarization
DAFNE-2: with a scan of 20 points, 50 pb-1 per point, (one year of data
taking)
 from 40000 × e (at threshold) to 10000 × e (a 2.5 GeV)
 Total number of events ~ 5 × 105 × e
With e = 10% DAFNE-2 is 10 times better Babar (current results)
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
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h, h’ at DAFNE-2
F-factory = h ed h’ factory
BR(f  hg) = 1.3 ×10-2
 Nh(20 fb-1) ~ 9 × 108
BR(f  h’g) = 6.2 ×10-5
 Nh’(20 fb-1) ~ 5 × 106
Monochromatic prompt photon: clear signature
Mixing h – h’: Uncertainty dominated by systematics;
improvement can come by measuring main h’ BR’s
h decays:
h  p0gg (test ChPT; major improvements expected with 20 fb-1)
Dalitz decays: h  e+e-g, m+mg, e+e-e+e-  Transition FF
h  p+pe+e- (Test of CP violation, analogous to KL  p+pe+e- )
Improvements on forbidden/rare decays
h’ decays:
Dalitz plot of h’hp+p-  scalar amplitude
h’p+pp0  first observation / isospin violation
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
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Scalars at DAFNE-2
Beside gg process, scalars f0(980), a0(980)
will be copiously produced in the radiative decay of the f
•With 20 fb-1 the decay f  f0g , f0 K+K- (K0K0) (expected BR
~ 10-(6-8) ) will be well measured (105 K+K- and 103 K0K0).
direct measure of the gfKK coupling
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
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Detector Issues
(KLOE taken as reference)
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
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The ingredients of KLOE success
E.M. Calorimeter:
Drift Chamber:
Full angular coverage
Good momentum resolution
Exceptional timing capabilities
Large tracking volume
Large lever arm
Minimization of materials
Excellent e/p separation based on t.o.f.
Good p0 reconstruction capabilities
Full kinematical reconstruction of events
Maximization of efficiency for long-lived particles (K± ,KL)
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
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There can be improvements
Still, based on our experience, some possible modifications
can improve KLOE performance
• Use of a lower magnetic field. This can increase acceptance
for several of the above mentioned channels and ease
pattern recognition
• Insertion
of a vertex chamber. At present, first tracking layer
is at 30 cm (i.e. 50 S) from the I.P.
• Try
some z coordinate reconstruction in the drift chamber.
Pattern recognition would benefit of it.
• Increase
calorimeter’s readout granularity. Can improve
photon counting, as well as particle identification.
• A small
angle tagger for gg physics
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
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Conclusion
A high luminosity Ffactory is a perfect tool to study a wide
variety of relevant physics topics in several distinct and
complementary ways
With KLOE we have learned a lot on how to perform these
measurements and have solid ideas on the potentialities of
our detector
We have also several ideas on the potential improvements
that can be done and intend to study in detail the feasibility
and relevance of all of them in the coming months
The high energy program is important. The detector upgrade
discussed is fine for that (Only FF measurement requires a
slight upgrade). Precise measurements (of R for example)
need confirmation from different detectors/experiments!
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
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Time schedule
Conceptual Design Report of the accelerator  end 2006
international collaboration on the machine design is highly desirable
Preliminary Letters of Intent for experiments are in preparation.
We need to have an international collaboration.
Experiment Letters of Intent  Spring 2006
Some of you are already present in the high
energy program. If other people are interest,
they are very welcome!
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
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SPARES
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
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Prospectives for h & scalars
physics@20fb-1
Large samaple of h  9x108 and h’  4x106
Intersting channels
h p0gg
BR( 8.0 ± 2.7 ) × 10 with e=4.63%
study of gg spectrum
h, h’ g l+l-,lll(‘)l(‘)
h p+p e+e
h’ hp+p
3000 evts
(Dalitz & double dalitz decays) with high statistics
-
test of CP violation beyond SM
sensitive to s(600) expcted 200.000 events
With 20 fb-1 f  f0g , f K+K- (KK) (expected BR ~ 10-6(-8) ) well measured
(105 K+K- and 103 KK), direct measure of the gfKK coupling
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
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ISR Luminosity for different c.m. energies
-
We integrated dL/dm for
25 MeV bin sizes.
2fb-1 @ s=1.02 GeV
2fb-1 @ s=2.4 GeV
1pb-1
89fb-1 @ s=10.6 GeV
2fb-1
@ 2.4 GeV
89fb-1 @ 10.6 GeV
1
GeV
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
GeV
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1010  (dam)stat
KLOE Data at off peak (1 GeV)
(started at mid of Dec. 05)
sp+pp0  329.8 nb
sp+pg  4.4 nb
6
5
4
3
2
1
0
• stat. error on am: [1.5-2.5]10-10 (300-100 pb-1)
• comparible with the expected syst.error
sp+pp0  6 nb, sqrt(s)=1003.71 MeV
(from SND, PRD66 (2002) 032001)
(dsppg/sppg )syst ~ 2% from region < 0.35 GeV2
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
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Impact of DAFNE-2 on the threshold region
1) total accuracy better than 3% in the
(dsppg/sppg )stat
region <0.35 GeV2 ( ~3 × 10-10) is a hard task
bin width = 0.01 GeV2
efficiency = 50% flat
for KLOE
2) This accuracy could be improved in the
future, using ISR at DAFNE-2 (off-peak)
during the KLOE
data taking campaign @ s = 1 GeV
we can learn a lot
DaFne upgrade – G. Venanzoni, Novosibirsk, 27 Feb – 2 Mar 2006
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