C Curceanu On behalf of SIDDHARTA LNF SC

C. Curceanu (On behalf of SIDDHARTA) LNF – SC, 41 th meeting, 22 Nov. 2010

SIDDHARTA 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: JRA 10 – FP 6 - I 3 HP Network WP 9 – LEANNIS – FP 7 - I 3 HP 2

SDDs & Target (inside vacuum) Kaon detector

SIDDHARTA data: - Kaonic Hydrogen: advanced analysis; Ph D - Kaonic deuterium: as an exploratory first measurement ever, advanced analysis; Ph D - Kaonic helium 4 – published in Phys. Lett. B 681 (2009) 310; another paper in preparation - Ph. D - Kaonic helium 3 – first measurement in the world, paper submitted to publication - Ph D SIDDHARTA – important school for young researchers

Data taking periods of SIDDHARTA in 2009 K-He 4 data with Fe source 55 Fe source: Good for reduce sys. error on K-4 He Bad for “background” events on K-H, K-D Removed 55 Fe source in other data PLB 681(2009)310 Use of Mn Ka (5. 9 ke. V) from 55 Fe Systematic error = +/-2 e. V

KHe-4 energy spectrum at SIDDHARTA 2009 PLB 681(2009)310 K-He data taking Ti foil No-coincidence Target Fe 55 Degrader coincidence First observation in He 4 gas

Data taking scheme at DAFNE Instead of Fe source, “X-ray tube” data taken calibration data Production data SDDs Ti/Cu foil degrader Scintillators X-ray tube

Energy calibration Cu Ka Ti Ka Calibration: periodic xray-tube switch on during beam Ti + Cu Ka lines Cu Kb Ti Kb Fe Ka Fe Kb Mn Ka Au La esc Cu Ka tail Zn Ka line shape to fit detector response (sum of 100 sdds with individual resolution, small asymmetry effect) tail energy (ke. V) 8

Selected with K+K& SDD timing Not correlated to Kaon signals Production data Calibration data with X-ray tube SDD X-ray energy spectra Kaon detector Time difference between SDD & Kaon detector

Kaonic Helium-3 energy spectrum First observation of kaonic He-3 X-rays X-ray energy of K-3 He 3 d-2 p K-3 He Ti Ka QED value: (3 d-2 p) K-C K-O K-N ar. Xiv: 1010. 4631 Submitted to PLB

K-4 He (3 d-2 p) K-3 He (3 d-2 p) DAFNE shutdown in Summer

NEW Kaonic Helium-4 energy spectrum X-ray energy of K-4 He 3 d-2 p K-4 He (3 d-2 p) QED value: Ti Ka K-C K-O

Comparison of results Shift [e. V] Reference KEK E 570 +2± 2± 2 PLB 653(07)387 SIDDHARTA (He 4 with 55 Fe) +0± 6± 2 PLB 681(2009)310 SIDDHARTA (He 4) +5± 3± 4 Preliminary SIDDHARTA (He 3) -2± 2± 4 ar. Xiv: 1010. 4631, Submitted to PLB *error bar

Comparison of results Shift [e. V] Reference KEK E 570 +2± 2± 2 PLB 653(07)387 SIDDHARTA (He 4 with 55 Fe) +0± 6± 2 PLB 681(2009)310 SIDDHARTA (He 4) +5± 3± 4 Preliminary SIDDHARTA (He 3) -2± 2± 4 ar. Xiv: 1010. 4631, Submitted to PLB Not as large as 40 e. V in both of He-3 & He-4 Question: both 0 -e. V shift? Within error, consistent with 0 e. V, BUT Within error, cannot exclude 0 -e. V shift SIDDHARTA 2/ E 17: More precision measurement on KHe *error bar

Energy vs. timing Hydrogen timing cut Kaonic hydrogen Deuterium Simultaneous fit estimated from deuterium spectrum

Spectra normalized by Luminosity [pb-1] Counts / 50 [e. V] / Luminosity [pb-1] KC Black : hydrogen Red : deuterium Ti KC Kaonic hydrogen Kα KO KAl Normalized yields -> well agree the same T&P Kcomplex the same stopping power Energy [e. V]

Subtracted spectrum with a simple fit result Counts / lumi [pb-1] / 50 [e. V] K complex region Energy [e. V] the other kaonic lines

Simultaneous fit The yields of background Kaonic lines were estimated from deuterium spectrum with the simultaneous fit.

Kp. X @ KEK (’ 97) Iterative fit 1) Initial fit with only Ka region 2) Fixing shift & width Free intensity 3) Fixing intensity Free shift & width

t) e p y ft o e l mp exa ( y li e r P nar i m fi f o

Preliminary

Kaonic hydrogen result shift about 300 e. V Width about 500 e. V Recent theoretical values Phys Rev Lett. 94 (2005) 213401 Width [e. V] Empty : using Deser-Trueman formula Full : by including isospin breaking corrections Circle : their theory (Chiral SU(3) effective field theory) Rectangle : with fit restricted to the DEAR data SIDDHARTA preliminary DEAR KEK Izycki Davies Error : statistical only Bird Shift [e. V]

Systematic errors (undergoing)

Kaonic deuterium data 25

Kaonic deuterium spectrum: fit for shift 500 e. V, width = 1000 e. V, Ka / Kcomplex = 0. 4 KC (5 -4) KC (6 -5) KO (7 -6) KN KO (6 -5) Cu Ka (9 -7) Kd Ka KC (7 -5) KAl (8 -7) KAl Pb (10 -8) Lb KTi (11 -10) Kd Kcom X ray energy (ke. V) KN (5 -4) KAl (7 -6) KC (6 -4)

Summary of SIDDHARTA analyses status K-p shift ~ 300 e. V, width ~500 e. V, paper to be submitted early 2011 K-d first measurement ever, exploratory measurement, small signal, significance ~ 2 s, paper in preparation KHe 4 measured for the first time in gaseous target, one paper published (PLB) and another one in preparation KHe 3 first time measurement , paper submitted to publication (PLB and ar. Xiv) 27

SIDDHARTA 2

SIDDHARTA 2 strategy – phases 1) Kaonic deuterium measurement - 1 st measurement: (in 2012 ? ) and R&D for other measurements 2) Kaonic helium transitions to the 1 s level – 2 nd measurement, R&D 3) Other light kaonic atoms (KO, KC, …) 4) Heavier kaonic atoms measurement (Si, Pb…) 5) Kaon radiative capture – L(1405) study 6) Investigate the possibility of the measurement of other types of hadronic exotic atoms (sigmonic hydrogen ? ) 7) Kaon mass precision measurement at the level of <10 ke. V

SIDDHARTA SETUP

Phase 1 • new IR (beam pipe) • new vacuum chamber • more cooling power • new target cell • new SDD arrangement • new shielding • improved trigger scheme • R&D for other measurements

Vacuum chamber and new target cell

New cooling systems Target cooling: 1 Leybold – 16 W @ 20 K Liquid hydrogen cooling lines, new target cell, selected materials SDD cooling: 4 Cryo. Tiger – 60 W @ 120 K Liquid argon cooling lines: SDD cooling to 100 – 120 K

Kaon trigger / shielding planar Si SDD chip target cell kaon trigger Pb-shielding K-

Additional -ray detectors -ray detection: few Me. V to 100 Me. V

Detector arrangement below IR 50 cm HP-Ge 20 cm 2, GMX coaxial LN 2 5 – 1000 ke. V Ortec solid target K+- LN 2 Pb shielding HP-Ge 8 cm 2, semi planar 6 – 500 ke. V Eurisys

DAFNE represents (as always did) an EXCELLENT FACILITY in the sector of low-energy interaction studies of kaons with nuclear matter. It is actually the IDEAL facility for kaonic atoms studies and the SIDDHARTA-2 collaboration, with its broad international nature, is convinced that NOW AND HERE the measurements could be done. (Or else, the future in this sector might remain open, with all its fundamental implications).

We’ll be back!

Acknowledgements The SIDDHARTA 2 Collaboration is very grateful to the DA NE staff for the continuous support and help not only in running DEAR and SIDDHARTA, but in having it made possible to pursue the adventure by proposing the SIDDHARTA 2 measurements. We thank as well all LNF services whose contribution was and we are sure, will continue to be fundamental. We are as well grateful to the LNF-INFN Director, Prof. Mario Calvetti, for his support and continuous encouragement. We acknowledge the INFN support and help (in particular to Prof. A. Bracco). We acknowledge the support in the framework of EU FP 6 and FP 7 Hadron. Physics and Hadron. Physics 2 projects. Last but not least we thank all our theoretician colleagues and friends in LEANNIS. We thank as well the following financing agencies: OEAW (SMI), IFIN-HH.