X-ray Spectroscopy of Kaonic Atoms at DAfNE

Antonio Romero Vidal Laboratori Nazionali di Frascati, Rome, Italy

on behalf of the SIDDHARTA collaboration 1 ---- MESON 2010 , 12/06/2010 , A. Romero ---- SIDDHARTA collaboration SIlicon Drift Detector for Hadronic Atom Research by Timing Applications

LNF- INFN, Frascati, Italy SMI - ÖAW, Vienna, Austria IFIN – HH, Bucharest, Romania Politecnico, Milano, Italy MPE, Garching, Germany PNSensors, Munich, Germany RIKEN, Japan Univ. Tokyo, Japan Victoria Univ., Canada

EU Fundings: JRA10 – FP6 - I3HP Network WP9 – LEANNIS – FP7- I3HP2 2 ---- MESON 2010 , 12/06/2010 , A. Romero ---- SIDDHARTA - What is it ?

2

• Goal: measure the shift and broadening X 144 cm SDDs of the X ray transition of light kaonic atoms. SDDs •The ground state is affected by the K- of the and the Scint nucleus. • Delivers input for effective F e+ e- theories in low energy QCD. Scint Triple coincidence: K+ SDDX * ScintK * ScintK

New X-ray detectors (SDD Silicon Drift Detectors) E (2-1) (EM) = 6.480 keV . timing capability  trigger for background suppression . excellent energy resolution (140 eV at 6.0 KeV) . high efficiency, large solid angle. 1s level shifted and broadened . performance in accelerator environment

3 ---- MESON 2010 , 12/06/2010 , A. Romero ---- 3 Hadronic atoms in QCD

__ _ Objects of type (K X), (p-, X) with X = p, d, 3He, 4He,.. or p+ p- p K

Bound electromagnetically, binding well known Strong interaction (mediated by QCD)  modify binding  decay of object

in some cases: small perturbation  energy shift and width can be related to T-matrix elements at threshold (Deser1 type formulas)

compare to results from low energy scattering experiments2

Low energy phenomena in strong interaction can not be described in terms of quarks and gluons, instead effective theories are used (they have some degrees of freedom to accomodate experimental data)

1 Deser relation in some cases not sufficient to compare to high precision experimental data 2 Problems: extrapolation to E=0 and quality of old experimental data ---- MESON 2010 , 12/06/2010 , 4 A. Romero ---- QCD predictions

Chiral perturbation theory was extremely successful in describing systems like pH, but can not be used for KH. Main reason is the presence of the L(1405) resonance only 25 MeV below threshold.

scattering data Effective field theory atomic X ray data energy, width of resonances

There exist non-perturbative coupled channel techniques which are able to generate the L(1405) dynamically as a Kbar N quasibound state and as a resonance in the p S channel

---- MESON 2010 , 12/06/2010 , 5 A. Romero ---- Kaonic hydrogen – Deser formula

____

With a0, a1 standing for the I=0,1 S-wave KN complex scattering lengths in the isospin - limit (md = mu), m being the reduced mass of the K p system, and neglecting isospin-breaking corrections, the relation reads:

G 2p 3 2 -1  +i  2 m a -  412 fm eV a - 2 m K p K p 1 … a linear combination of the isospin a -  (a + a ) K p 2 0 1 scattering lengths a0 and a1 to disentangle them, also the kaonic deuterium scattering length is needed

„„By using the non-relativistic effective Lagrangian approach a complete expression for the isospin-breaking corrections can be obtained; in leading order parameter-free modified Deser-type relations exist and can be used to extract scattering lenghts from kaonic atom data“2 2Meißner,Raha,Rusetsky, 2004

---- MESON 2010 , 12/06/2010 , 6 A. Romero ---- Kaonic deuterium

For the determination of the isospin dependent

scattering lengths a0 and a1 the hadronic shift and width of kaonic hydrogen and kaonic deuterium are necessary !

Elaborate procedures needed to connect the observables with the underlaying physics parameters.

“To summarize, one may expect that the combined larger analysis of the forthcoming high-precision data from than DEAR/SIDDHARTA collaboration on kaonic hydrogen leading and deuterium will enable one to perform a stringent term test of the framework used to describe low–energy kaon deuteron scattering, as well as to extract the values of a0 and a1 with a reasonable accuracy. However, in order to do so, much theoretical work related to the systematic calculation of higher-order corrections within the non-relativistic EFT is still to be carried out.” (from: Kaon- scattering lengths from kaonic deuterium, Meißner, Raha, Rusetsky, 2006, arXiv:nucl-th/0603029)

---- MESON 2010 , 12/06/2010 , 7 A. Romero ---- Summary of physics framework and motivation

 Exotic (kaonic) atoms – probes for strong interaction

 hadronic shift ε1s and width Γ1s directly observable  experimental study of low energy QCD. Testing chiral symmetry breaking in strangeness systems

 Kaonic hydrogen  Kp simplest with strangeness  kaonic hydrogen„„puzzle“ solved – but: more precise experimental data important  kaonic deuterium never measured before

 Information on L(1405) sub-threshold resonance  responsible for negative real part of scattering amplitude at threshold  important for the search for the controversial „„ deeply bound kaonic states” present / upcoming experiments (KEK,GSI,DAFNE,J-PARC)

 Determination of the isospin dependent KN scattering lengths  no extrapolation to zero energy

---- MESON 2010 , 12/06/2010 , 8 A. Romero ---- AIMS OF SIDDHARTA

• Improve the previous measurements of the Kaonic hydrogen shift and width.

• First observation of the Kaonic deuterium K lines.

4 • Precise measurement of the Kaonic He L transition.

3 • First observation and precise measurement of the Kaonic He L transition.

9 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Kaon-nucleon interaction at low energies

Experimental data are available for:

1) K- p cross section for elastic and inelastic processes.

2) Branching ratios for K- p absorption at rest.

3) πΣ invariant mass distribution below K- p threshold, wich exhibits the Λ(1405) resonance.

4) 1s level shift and width of K- p atom determined through Xray measurements. (SIDDHARTA)

10 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Scattering data vs X-ray measurements Analyises on scattering data have been usually made by using a K-matrix formulation with the assumption that its elements are smooth functions of energy, allowing extrapolation down to threshold and below

Scattering data lead to a negative shift, Scattering data -> ε<0 wich means that strong interaction is Old X-ray measurements -> ε>0 repulsive type and shifts the EM level to “Kaonic Hydrogen puzzle” a less bound energy. 11 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Kaonic Hydrogen Puzzle

KeK results

KpX at KEK results [6],

Solved !!

[6] M.Iwasaki et al., Phys. Rev. Lett. 78 (1997) 3067 T.M.Ito et al., Phys. Rev. A58 (1998) 2366.

---- MESON 2010 , 12/06/2010 , 12 A. Romero ---- DEAR results [2002-2005] collision Non collision

Confirming the results found at KeK.   -193 37(stat.)  6(syst.)eV G  249 111(stat.)  39(syst.)eV No deuterium measurements due to the too much high background

---- MESON 2010 , 12/06/2010 , 13 (KeK) A. Romero ---- Previous X-ray measurements summary

1000 Repulsive type Attractive

800

KpX 1980 ,

600 (KeK) etal [eV]

DEAR Izycki

1s G

400

width

, 1983 , , 1979 ,

200 etal

et al et

Bird Davies Davies 0 -500 0 500 shift 1s [eV] 14 ---- MESON 2010 , 12/06/2010 , A. Romero ---- DAfNE UPGRADE, 2008

---- MESON 2010 , 12/06/2010 , 15 A. Romero ---- DAFNE

- collider, energy at phi resonance phi produced nearly at rest. (boost: 55 mrad crossing angle → 28 MeV/c) charged from phi decay: Ek = 16 MeV degrade to < 4MeV to stop in gas target

Φ production cross section ~ 3000 nb (loss-corrected) Integr. luminosity 2009 ~ 6 pb-1 per day 1) (~ 107 K± ) SIDDHARTA is set up here (increased by crabbed waist scheme) Peak luminosity ~ 3 × 1032 cm-2 s-1 = 450 Hz K± 1) compare situation during DEAR data taking (2002) we can not use kaons produced during currents ~ 1200/800 ~ 1 pb-1 per day, peak ~ 3×1031 cm-2 s-1 injections. 16 DAFNE background

SYNCRONOUS: It‟s associated to K production, or F decays. It can be considered a hadronic background.

ASYNCRONOUS: It‟s dued to final products of electromagnetic cascade produced in the accelerator and to other materials activated by lost from the beam. Moreover it also contains Touschek effect (same bunch particles‟ interactions)

The main contribute comes from the asyncronous background, wich can be reducted using a trigger and fast detectors: SDD (Silicon Drift Detector)

17 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Target

1 bar

Low density gas • Hydrogen • Deuterium • Helium4, Helium3 18 ---- MESON 2010 , 12/06/2010 , A. Romero ---- SIDDHARTA SETUP

(used for calibration)

(two scintillators In coindidence with the 19 DAFNE RF) ---- MESON 2010 , 12/06/2010 , A. Romero ------MESON 2010 , 12/06/2010 , 20 A. Romero ---- K-

e-

f e+

K+ ---- MESON 2010 , 12/06/2010 , 21 A. Romero ---- Kaon trigger

Beam pipe

---- MESON 2010 , 12/06/2010 , 22 A. Romero ---- Target (filled with Hydrogen, helium or deuterium)

SDD’s

---- MESON 2010 , 12/06/2010 , 23 A. Romero ---- 144 SDD’s 1cm x 1cm

---- MESON 2010 , 12/06/2010 , 24 A. Romero ---- Trigger

1 ns Kaons Kaons are detected by TOF. Two scintillators 2.8 ns in coincidense with the collission.

MIP‟s

SelfMIP‟s trigger Drift time

Rejection factor ~104

25 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Calibration runs Every 10 normal runs, a calibration run is done using a X-ray tube which activates the Ti and Cu foils, in order to check the setup stability. Ti K Ti Kb

(data with Fe source)

Cu K Cu Kb

Resolution at 6.4 KeV (FWHM) ~ 140 eV

26 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Kaonic He4. First results

Physics Letters B 681 (2009) 310-314

(Diana Laura Sirghi talk about Kaonic Helium) 27 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Fit of Kaonic Helium 4. New data

KHe used for

gas stop transition e.m.energy events 2) optimization - (3-2) 6.464 1047 ± 37 + physics interest1) (4-2) 8.722 154 ± 21

KHe (3 KHe (5-2) 9.767 91.8 ± 19 data from setup 2 (6-2) 10.333 82.4 ± 25

(no Fe55 source) higher < 11.63 131 ± 41

40eV 4) Shift compatible p r e l i m i n a r y-

with zero

Counts / Counts

KC (5 KC

2)

-

2)

-

2)

-

5)

-

KHe (4 KHe

5)

Ti K Ti

-

KHe (6 KHe

high

6)

-

4)

-

KC (6 KC (5 KHe KO (6 KO

1 (7 KO

) compare KEK E570 L KHe KN (5 KN KHe L lines in liquid He, consistent result, first measurement in gas

X ray energy (keV) ---- MESON 2010 , 12/06/2010 , A. Romero ---- 28 Fit of Kaonic Helium 3

transition e.m.energy events 2)

- (3-2) 6.224 1209 ± 40 (4-2) 8.399 220 ± 22 ±

KHe (3 KHe (5-2) 9.406 90.0 18 KHe3 (6-2) 9.953 65.8 ± 24 higher < 11.4 397 ± 40 never measured before ! 40eV p r e l i m i n a r y

Shift compatible

4) -

with zero / Counts

2)

-

KC (5 KC

2)

-

KHe (6 KHe

2)

5)

-

-

Ti K Ti

high

KHe (4 KHe

6)

4)

-

-

5)

-

KC (6 KC

KHe (5 KHe

KHe L KHe KO (7 KO (5 KN KO (6 KO

X ray energy (keV)

---- MESON 2010 , 12/06/2010 , A. Romero ---- 29 Kaonic hydrogen data

---- MESON 2010 , 12/06/2010 , 30 A. Romero ---- Kaonic deuterium data

---- MESON 2010 , 12/06/2010 , 31 A. Romero ---- Kaonic hydrogen fit

from the kaonic hydrogen spectrum the Kd specturm was subtracted to get rid of the kaonic background lines KO, KN. 290 pb-1 KH For the signal 8 voigtians with given gauss resolution and free identical lorentz width are used for (2-1),.. (9-1) The position pattern is fixed by the QED values. The intensities of (2-1),(3-1) and (4-1) are free, those of the higher transitions are KH KH (4-1),.. coupled according to theoretical expectatuions (2-1) KH (9-1) (cascade calculation, Koike„s values) (3-1) Shift ~ -270 eV +- < 30 eV (stat) Width ~ 500 eV +- < 80 eV (stat) p r e l i m i n a r y

In the final analysis the backgound Note: Khigh energy (keV) can be determined from fitting the KD data yield pattern and then include the pattren in the KH fit. ---- MESON 2010 , 12/06/2010 , A. Romero ---- Future plans

SIDDHARTA2

• SIDDHARTA upgrade (from 2012) for : • Kaonic deuterium precision measurement • Other kaonic atoms (light and heavy) (Si,Pb …) • Charged kaon mass precision measurement. • Feasibility study for Sigmonium atoms. • Kaonic Helium transitions to the 1s level.

33 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Conclusions • SIDDHARTA has performed first class measurements of kaonic atoms. • K-p shift ~ -270 eV, width ~500 eV higher precision than in DEAR. Preliminary results. • SIDDHARTA2 plans solving kaonic atoms campaign (2012). • K-d exploratory measurement, small signal, significance ~ 2s. • DAFNE represents an unique opportunity to study in a complete way the kaon-nucleon/nuclei physics at low energy.

Thank you very much !

34 ---- MESON 2010 , 12/06/2010 , A. Romero ---- SPARES

---- MESON 2010 , 12/06/2010 , 35 A. Romero ---- Kaonic Atoms Previous results The SIDDHARTA Kaonic Hydrogen Near Future Conclusions experiment analysis

36 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Kaonic Atoms Previous results The SIDDHARTA Kaonic Hydrogen Near Future Conclusions experiment analysis

Kaonic Deuterium

37 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Summary and Outlook

SIDDHARTA data taking finished Nov 2009. Preliminary results:

KHe4 measured in gaseous target, shift zero within errors (confirming E570)

KHe3 first time measurement, shift zero within errors (s = 2.7 eV stat. 4 eV syst.)

K-p shift ~ 270 eV, width ~500 eV higher precision then in DEAR

K-d first measurement ever, exploratory measurement, small signal, significance ~ 2s

hopefully extension of the experimental program ~2012- with improved technique - remeasure Kd, other light atoms, heavys, Kp → g L*

38 MENU 2010, Cargnelli Kaonic Atoms Previous results The SIDDHARTA Kaonic Hydrogen Near Future Conclusions experiment analysis

39 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Kaonic Atoms Previous results The SIDDHARTA Kaonic Hydrogen Near Future Conclusions experiment analysis

Electronic hydrogen Kaonic hydrogen

K -

K - - e n=25

n=2 p p n=1

Finaly, the Kaon is absorved by the nucleus

40 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Kaon-nucleon interaction at low energies

Anti(K)-N interaction at low energies has complex dynamical aspects due to This region is also dominated by the several πY channels opening s-wave Λ(1405) resonance, wich at K- p threshold (1432 only decays in Σπ. MeV): This resonance also couples to the anti(K)-N system but it doesn‟t decay to it since it‟s ~ 30 MeV below the threshold

---- MESON 2010 , 12/06/2010 , A. Romero 41 ---- Exotic atoms In order to determine the energy shift , the Klein-Gordon equation with E.M. energy of the unshifted line must first Coulomb potential with second order be calculated perturbation theory corrections Corrections include vacuum polarization, electron screening, relativistic corrections to reduced mass, nuclear polarization and Lamb shift

---- MESON 2010 , 12/06/2010 , A. Romero 42 ---- Kaonic Atoms Previous results The SIDDHARTA Kaonic Hydrogen Near Future Conclusions experiment analysis

KpX at KEK, Japan Old experiments

43 [6] M.Iwasaki et al., Phys. Rev. Lett. 78 (1997) 3067 T.M.Ito et al., Phys. Rev. A58 (1998) 2366. ---- MESON 2010 , 12/06/2010 , A. Romero ---- Kaonic Atoms Previous results The SIDDHARTA Kaonic Hydrogen Near Future Conclusions experiment analysis

DEAR

• Experiment at DAFNE before SIDDHARTA.

• It used CCD detectors (slow time response)

  -193 37(stat.)  6(syst.)eV G  249 111(stat.)  39(syst.)eV

44 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Kaonic Atoms Previous results The SIDDHARTA Kaonic Hydrogen Near Future Conclusions experiment analysis

Degrader optimization

Degrader thickness is changed to optimize the number of kaons inside the target

50

40

1 -

30 He/pb

- 20 K

10

0 250 300 350 400 450 500 550 thickness to be added to base [µm] 45 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Kaonic Atoms Previous results The SIDDHARTA Kaonic Hydrogen Near Future Conclusions experiment analysis

Kaonic Hydrogen

• Systematics are being studied. K-C

• Publication coming Ti Ka soon.

K-H (region K-C of interest)

46 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Kaonic Atoms Previous results The SIDDHARTA Kaonic Hydrogen Near Future Conclusions experiment analysis

Kaonic He^4

More data under KHe Ka analysis

KHe Kb

Energy (eV) 47 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Kaonic Atoms Previous results The SIDDHARTA Kaonic Hydrogen Near Future Conclusions experiment analysis

Kaonic He^3

48 ---- MESON 2010 , 12/06/2010 , A. Romero ------MESON 2010 , 12/06/2010 , 49 A. Romero ---- Kaonic atoms  Energy shift  and line width G of 1s Scattering lengths can be expressed in terms state are related to real and of antiK-N isospin dependent scattering imaginary part of the S-wave lengths: scattering length:

aK - p  Neglecting isospin-breaking corrections Deser-Trueman formula a0 (I  0) + a1(I 1) a -  [1] for kaonic hydrogen and K p 2 deuterium state: 1 mN + mK a -  (3a + a ) + C K d mK 1 0 2 mN + 2

iG 3 2 eV  +  2 m a -  412 a - K p fm K p 2 Includes all higher contributions related to the iG 3 2 eV pysics associated to the K- d three body  +  2 m a -  601 a - 2 K d fm K d problem.

[1]---- S.DeserMESON et al., Phys.Rev. 2010 ,96 (1954) 774; It can be numerically calculated solving 12/06/2010T.L.Truemann, , A. Romero Nucl. Phys. 26 (1961) 57; 50 A.Deloff, Phys. Rev. C13 (1976) 730. Faddeev equation ---- Kaon-nucleon interaction at low energies

Experimental data are available for:

1) K- p cross section for elastic and inelastic processes; 2) Branching ratios for K- p absorption at rest

3) πΣ invariant mass distribution below K- p threshold, wich exibits the Λ(1405) resonance 4) ----1sMESON level 2010shift , of K- p atom determined through Xray measurements 12/06/2010 , A. Romero 51 ---- The importance of a new Xray measurement

Wich is the scientific meaning of an Xray measurement on kaonic hydrogen? 1) Confirming the puzzle‟resolution understanding the Kaon-Nucleon interaction 2) Studying the structure of the Λ(1405) (composite, elementary 3q- state, anti(K)-N bound state....) 3) Xray results represent the only direct experimental evidence on the near-zero energy anti(K)-N interaction 4) Better understanding of the K-matrix 5) Reconcile Xray and scattering data (already attempted)

---- MESON 2010 , 12/06/2010 , A. Romero 52 ---- Contents

KAONIC HYDROGEN

K - p

53 ---- MESON 2010 , 12/06/2010 , A. Romero ---- The importance of a new Xray measurement

Wich is the scientific meaning of an Xray measurement on kaonic hydrogen? 1) Confirming the puzzle‟resolution understanding the Kaon-Nucleon interaction 2) Xray results represent the only direct experimental evidence on the near-zero energy anti(K)-N interaction 3) Better understanding of the K-matrix 4) Reconcile Xray and scattering data (already attempted)

---- MESON 2010 , 12/06/2010 , A. Romero 54 ---- Introduction Previous results The SIDDHARTA Kaonic Hydrogen Near Future Conclusions experiment analysis

Kaonic atom formation Auger e- K - e-

n=25

Nucleus n=1 n=2

Initial capture

55 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Introduction Previous results The SIDDHARTA Kaonic Hydrogen Near Future Conclusions experiment analysis

Kaonic atom formation Auger e- e-

K -

n=25

Nucleus n=1 n=2

cascade

56 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Introduction Previous results The SIDDHARTA Kaonic Hydrogen Near Future Conclusions experiment analysis

Kaonic atom formation X-RAY

n=25

K - Nucleus n=1 n=2

Strong interaction

57 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Kaonic Atoms Previous results The SIDDHARTA Kaonic Hydrogen Near Future Conclusions experiment analysis

Energy levels for Kaonic Hydrogen

n s p d f 4 3

2 E2p

Kb ~ 6..47 (EM) D G K E2p1s

Shift 1s  Eexp - EEM

} 1s 1 EShift1s negative -> Repulsive type Shift positive -> Atractive type

58 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Kaonic Hydrogen Puzzle

1979-1983: first kaonic hydrogen measurements[5]

[5] J.D.Davies et al., Phys Lett 83 (1979) 55; M.Izycki et al., Z.Phys. A297 (1980) 11; P.M.Bird et al., Nucl.Phys. A404 (1983) 482. ---- MESON 2010 , 12/06/2010 , A. Romero 59 ---- Kaonic Atoms SIDDHARTA Previous results Experiment Analysis Conclusions

Dreser-Trueman Formula

Energy shift  and line width G of 1s state are related to real and imaginary part of the S-wave scattering length:

iG - K p 3 2 eV  - +  2 m - a -  412 a - K p 2 K p K p fm K p

iG - K d 3 2 2 eV  - +  2 m - a -  601 a - K d 2 K d K d fm K d

(Papers)

60 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Contents

• Introduction • Previous results •The SIDDHARTA experiment • Kaonic Hydrogen analysis • Near future • Conclusions

61 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Kaonic Atoms SIDDHARTA Previous results Experiment Analysis Conclusions

Dreser-Trueman Formula

Energy shift  and line width G of 1s state are related to real and imaginary part of the S-wave scattering length:

iG - K p 3 2 eV  - +  2 m - a -  412 a - K p 2 K p K p fm K p

iG - K d 3 2 2 eV  - +  2 m - a -  601 a - K d 2 K d K d fm K d

(Papers)

62 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Kaonic Atoms SIDDHARTA Previous results Experiment Analysis Conclusions

Isospin dependent scattering lengths

Scattering lengths can be expressed in terms of antiK-N isospin dependent scattering lengths:

a0 (I  0) + a1(I 1) a -  K p 2

1 mN + mK a -  (3a + a ) + C K d mK 1 0 2 mN + 2

Includes all higher contributions related to the pysics associated to the K-d three body problem. It can be numerically calculated solving Faddeev equation

63 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Fit of Kaonic Helium 4

KHe used for

gasstop transition e.m.energy events 2) optimization - (3-2) 6.464 1047 ± 37 + physics interest1) (4-2) 8.722 154 ± 21

KHe (3 KHe (5-2) 9.767 91.8 ± 19 data from setup 2 (6-2) 10.333 82.4 ± 25

(no Fe55 source) higher < 11.63 131 ± 41 4) p r e l i m i n a r y- shift = + 2.1 eV

Counts / bin / Counts +- 2.9 eV (stat.)

+- 4 eV (syst.) (5 KC

2)

-

2)

-

2)

-

5)

-

KHe (4 KHe

5)

Ti K Ti

-

KHe (6 KHe

high

6)

-

4)

-

KC (6 KC (5 KHe KO (6 KO

1 (7 KO

) compare KEK E570 L KHe KN (5 KN KHe L lines in liquid He, consistent result, first measurement in gas

X ray energy (keV) MENU 2010, Cargnelli 64 Fit of Kaonic Helium 3

transition e.m.energy events 2)

- (3-2) 6.224 1209 ± 40 (4-2) 8.399 220 ± 22 ±

KHe (3 KHe (5-2) 9.406 90.0 18 KHe3 (6-2) 9.953 65.8 ± 24 higher < 11.4 397 ± 40 never measured before ! p r e l i m i n a r y shift = - 1.7 eV

+- 2.7 eV (stat.)

4) -

Counts / bin / Counts +- 4 eV (syst.)

2)

-

KC (5 KC

2)

-

KHe (6 KHe

2)

5)

-

-

Ti K Ti

high

KHe (4 KHe

6)

4)

-

-

5)

-

KC (6 KC

KHe (5 KHe

KHe L KHe KO (7 KO (5 KN KO (6 KO

X ray energy (keV) MENU 2010, Cargnelli 65 Kaonic Atoms Previous results The SIDDHARTA Kaonic Hydrogen Near Future Conclusions experiment analysis DAFNE

• Phi factor at Frascati (Rome)

• e+ - e- beam collider

66 ---- MESON 2010 , 12/06/2010 , A. Romero ------MESON 2010 , 12/06/2010 , A. Romero 67 ------MESON 2010 , 12/06/2010 , A. Romero 68 ------MESON 2010 , 12/06/2010 , A. Romero 69 ------MESON 2010 , 12/06/2010 , 70 A. Romero ------MESON 2010 , 12/06/2010 , A. Romero 71 ------MESON 2010 , 12/06/2010 , A. Romero 72 ------MESON 2010 , 12/06/2010 , A. Romero 73 ------MESON 2010 , 12/06/2010 , A. Romero 74 ------MESON 2010 , 12/06/2010 , A. Romero 75 ------MESON 2010 , 12/06/2010 , A. Romero 76 ------MESON 2010 , 12/06/2010 , A. Romero 77 ---- 78 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Kaonic Atoms Previous results The SIDDHARTA Kaonic Hydrogen Near Future Conclusions experiment analysis

Kaonic Hydrogen

K-C

Ti Ka

K-H (region K-C of interest)

79 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Kaonic Atoms Previous results The SIDDHARTA Kaonic Hydrogen Near Future Conclusions experiment analysis

Kaonic Deuterium

80 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Kaonic hydrogen fit

from the kaonic hydrogen spectrum the KD specturm was subtracted to get rid of the -1 kaonic background lines KO, KN. 290 pb KH For the signal 8 voigtians with given gauss resolution and free identical lorentz width are used for (2-1),.. (9-1) The position pattern is fixed by the QED values. The intensities of (2-1),(3-1) and (4-1) are free, those of the higher transitions are KH KH (4-1),.. coupled according to theoretical expectatuions (2-1) KH (9-1) (cascade calculation, Koike„s values) (3-1) Shift ~ -270 eV Widht ~ 500 eV siddharta preliminary p r e l i m i n a r y

Note: Khigh energy (keV) In the final analysis the backgound yield pattern can be determined from fitting the KD data and then include the pattren in the KH fit. MENU 2010, Cargnelli Kaonic Hydrogen

• Systematics are being Ti Ka KH Kb KH Kg studied. KH Ka • Publication coming soon.

Shift ~ -270 eV Widht ~ 500 eV 82 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Kaonic Atoms Previous results The SIDDHARTA Kaonic Hydrogen Near Future Conclusions experiment analysis

83 ---- MESON 2010 , 12/06/2010 , A. Romero ---- The “Kaonic Hydrogen Puzzle”

All Xray experiments done until today This is in direct contradiction with the are in agreement abut the sign of ε: repulsive strong interaction found from ε>0 scattering data analyses!!!

---- MESON 2010 , 12/06/2010 , 84 A. Romero ---- SIDDHARTA2 physics – enriched case

SIDDHARTA2: 1) Kaonic deuterium measurement 2) Investigate the possibility of the measurement of other types of hadronic exotic atoms (sigmonic hydrogen ?) 3) Kaonic helium transitions to the 1s level 4) Other light kaonic atoms (KO, KC,…) 4) Heavy kaonic atoms measurement (Si, Pb…) 5) Kaon mass precision measurement at the level of <10 keV

6) Kaon capture in hydrogen – L(1405) study

---- MESON 2010 , 12/06/2010 , 85 A. Romero ---- Kaon-nucleon interaction at low energies

Experimental data are available for:

1) K- p cross section for elastic and inelastic processes.

2) Branching ratios for K- p absorption at rest.

3) πΣ invariant mass distribution below K- p threshold, wich exhibits the Λ(1405) resonance.

4) 1s level shift and width of K- p atom determined through Xray measurements.

86 ---- MESON 2010 , 12/06/2010 , A. Romero ---- Trigger

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