DaFne upgrade (as seen by a KLOE member)

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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
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Outline

• Status of DAFNE
• Upgrade of DAFNE
• Short term project
• Long term project
• Physics program at DAFNE-2
• Upgrade of the detector
• Conclusion

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DAFNE ee- machine at Frascati (Rome)
KLOE detector
e
e-
FINUDA detector
BRs for selected f decays BRs for selected f decays
KK- 49.1
KSKL 34.1
rp pp-p0 15.5

• ee? ? f ?s mf 1019.4 MeV
• beams cross at an angle of 12.5 mrad
• LAB momentum pf 13 MeV/c

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DA?NE performance up to Dec 2005
Peak Luminosity
1.4 x 1032 cm?2s?1
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Off peak run
Integrated Luminosity
Day performance 7-8 pb-1
Best month ?L dt 200 pb?1
Total KLOE ?L dt 2400 pb?1 (2001,02,04,05)
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DAFNE 24h Performance (Dec. 05)
1.2e-32
2 A
e-
e
1 A
8 pb-1
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Machine energy stability
?s monitored to within 70 keV Some variations in
2004 Stable (1019.3-1019.6) in 2005
2004
2005
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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?

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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 2.4
Integrated Luminosity per year (fbarn-1) gt10
Total integrated luminosity (5 years, fbarn-1) gt50 gt3
Peak luminosity (cm-1sec-2) gt8 1032 gt1032
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TDR in preparation necessary to submit the
project
IR
DAFNE 2 layout
Wigglers
rf
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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
• Spectroscopy (vector mesons)
• gg physics
• Time-like form factors (baryons and mesons)
• Radiative f decays
• Kaonic Nuclei

See presentation of S. Eidelman
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TOTAL CROSS SECTION R
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Impact of DAFNE-2 on inclusive measurement
20 pb-1
Lint (nb-1)
1) Most recent inclusive measurements MEA and
B antiB, with total integrated luminosity of 200
nb-1 (one hour of data taking at 1032 cm-2
sec-1).10 stat. 15 syst. errors 2) With 20
pb-1 per energy point, stat. errors on
d(Dahad)/Dahad ? O(5) systematic error will be
reduced as well 4) a precise comparison exclusive
vs. inclusive can be carried out

• MEA, 14 points, Lett. Nuovo Cim.30 (1981) 65
• B antiB, 19 points, Phys.Lett.B91 (1980) 155

?s (GeV)
?s (GeV)
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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
• Improvement on systematics come as well

4p
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Impact of DAFNE-2 on the range 1-2 GeV (3p)
using ISR _at_ 2.4 GeV (Statistical only)
BaBar, with the published Lint per point (90
fb-1) BaBar, with 10 ? (the present Lint
) DAFNE-2, with 2 fb-1 _at_ 2.4 GeV
comparison among the present BaBar analysis, an
(O(1 ab-1)) BaBar update, and Lint 2 fb-1 at
2.4 GeVper energy point _at_ DAFNE-2, in the impact
on d(Dahad) /Dahad p- p p0 O(9)
O(3) O(8)
statistical dshad / shad ()

• DAFNE-2 is competitive with B-factories with
  current statistics

?s (GeV)
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gg Physics at DAFNE-2

• gg? P p0 , h , h ? G(P?gg)
• gg? p0p0 , pp- , hp, hpp ? G(S?gg) / test of ChPT

• h, f0(980), a0(980) needs vs gt 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 vs
• Ggg di f0 e a0

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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 vs ? 1 GeV ok (Off f peak)
• ? More information from KLOE test run

BELLE
f0(980)
f2(1270)
gg ? pp-
Efficiency cut
Only data available gg ? p0p0 Crystal Ball _at_
DORIS 1990
Wgggt0.7 GeV
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Time-like form factors
Threshold for Baryons (GeV)
p 1.876
n 1.879
L 2.231 Np (pp- , np0)
S 2.378 Np (pp0 , np)
S0 2.385 Lg
S- 2.395 Np (np-)
D 2.464 Np
X0 2.630 Lp0
X- 2.643 Lp-
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Existing data
Proton data - type (1) Ipothesis GEGM
Neutron only FENICE (500 nb-1, 75 evts
signal) No data available on polarization
Proton data GE/GM - type (2)
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)
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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 ? hg) 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 BRs h decays h ? p0gg (test ChPT
major improvements expected with 20 fb-1) Dalitz
decays h ? ee-g, mm-g, ee-ee- ? Transition
FF h ? pp-ee- (Test of CP violation, analogous
to KL ? pp-ee- ) Improvements on
forbidden/rare decays h decays Dalitz plot of
h?hpp- ? scalar amplitude h?pp-p0 ? first
observation / isospin violation
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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? KK- (KK)
  (expected BR 10-(6-8) ) will be well measured
  (105 KK- and 103 KK). ?direct measure of the
  gfKK coupling

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Detector Issues (KLOE taken as reference)
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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/? separation based on t.o.f.
Good ?0 reconstruction capabilities
Full kinematical reconstruction of events
Maximization of efficiency for long-lived
particles (K ,KL)
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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 calorimeters readout granularity. Can
  improve photon counting, as well as particle
  identification.
• A small angle tagger for gg physics

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Conclusion

• A high luminosity ??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 further upgrade).
  Precise measurements (of R for example) need
  confirmation from different detectors/experiments!

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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
If you are interested to join this adventure, you
are welcome!
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SPARES
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Prospectives for h scalars physics_at_20fb-1
Large samaple of h ? 9x108 and h ? 4x106
Intersting channels
h? p0gg BR( 8.0 2.7 ) 10- with
e4.63 3000 evts
study of gg spectrum h, h? g ll-,lll()l()
(Dalitz double dalitz decays) with high
statistics h? pp- ee -
test of CP violation beyond SM h? hpp-
sensitive to s(600)
expcted 200.000 events
With 20 fb-1 f ? f0g , f? KK- (KK) (expected
BR 10-6(-8) ) well measured (105 KK- and
103 KK), direct measure of the gfKK coupling