Physics with the  PANDA Detector at GSI Diego Bettoni Istituto Nazionale di Fisica Nucleare, Ferrara Riunione WG Fisica Adronica e dello Spin Roma, 7 Novembre 2005

D. Bettoni -  PANDA at GSI 2 Outline Overview of the Project  PANDA Physics Program –Charmonium Spectroscopy –Hybrids and Glueballs –Hadrons in Nuclear Matter –Proton electromagnetic form factors in the timelike region The  PANDA Detector Concept Timeline Conclusions

D. Bettoni -  PANDA at GSI 3 The GSI FAIR Facility

D. Bettoni -  PANDA at GSI 4 The FAIR Complex

D. Bettoni -  PANDA at GSI 5 Primary Beams /s; 1.5 GeV/u; 238 U 28+ Factor over present in intensity 2(4)x10 13 /s 30 GeV protons /s 238 U 73+ up to 25 (- 35) GeV/u Secondary Beams Broad range of radioactive beams up to GeV/u; up to factor in intensity over present Antiprotons GeV Cooled beams Rapidly cycling superconducting magnets Key Technical Features Storage and Cooler Rings Radioactive beams e – A collider stored and cooled GeV antiprotons FAIR: Facility for Antiproton and Ion Research

D. Bettoni -  PANDA at GSI 6 Antiproton Physics Program Charmonium Spectroscopy. Precision measurement of masses, widths and branching ratios of all (c  c) states (hydrogen atom of QCD). Search for gluonic excitations (hybrids, glueballs) in the charmonium mass range (3-5 GeV/c 2 ). Search for modifications of meson properties in the nuclear medium, and their possible relation to the partial restoration of chiral symmetry for light quarks. Topics not covered in this presentation: Precision  -ray spectroscopy of single and double hypernuclei, to extract information on their structure and on the hyperon-nucleon and hyperon-hyperon interaction. Electromagnetic processes (DVCS, D-Y, FF...), open charm physics

D. Bettoni -  PANDA at GSI 7 The GSI  p Facility HESR = High Energy Storage Ring Production rate 2x10 7 /sec P beam = GeV/c N stored = 5x10 10 p High luminosity mode Luminosity = 2x10 32 cm -2 s -1  p/p~10 -4 (stochastic cooling) High resolution mode  p/p~10 -5 (el. cooling < 8 GeV/c) Luminosity = cm -2 s -1

D. Bettoni -  PANDA at GSI 8 The PANDA Collaboration U Basel IHEP Beijing U Bochum U Bonn U & INFN Brescia U & INFN Catania U Cracow GSI Darmstadt TU Dresden JINR Dubna (LIT,LPP,VBLHE) U Edinburgh U Erlangen NWU Evanston U & INFN Ferrara U Frankfurt LNF-INFN Frascati U & INFN Genova U Glasgow U Gießen KVI Groningen U Helsinki IKP Jülich I + II U Katowice IMP Lanzhou U Mainz U & Politecnico & INFN Milano U Minsk TU München U Münster BINP Novosibirsk LAL Orsay U Pavia IHEP Protvino PNPI Gatchina U of Silesia U Stockholm KTH Stockholm U & INFN Torino Politechnico di Torino U Oriente, Torino U & INFN Trieste U Tübingen U & TSL Uppsala U Valencia IMEP Vienna SINS Warsaw U Warsaw Spokesman: Ulrich Wiedner (Uppsala) More than 300 physicists from 48 institutions in 15 countries

D. Bettoni -  PANDA at GSI 9 QCD Systems to be studied in Panda

D. Bettoni -  PANDA at GSI 10 Charmonium Spectroscopy Charmonium is a powerful tool for the understanding of the strong interaction. The high mass of the c quark (m c ~ 1.5 GeV/c 2 ) makes it plausible to attempt a description of the dynamical properties of the (c  c) system in terms of non relativistic potential models, in which the functional form of the potential is chosen to reproduce the known asymptotic properties of the strong interaction. The free parameters in these models are determined from a comparison with experimental data. Non-relativistic potential models + Relativistic corrections + PQCD LQCD predicts spectrum  2  0.2  s  0.3

D. Bettoni -  PANDA at GSI 11 Experimental Study of Charmonium e + e - annihilation Direct formation only possible for J PC = 1 -- states. All other states must be produced via radiative decays of the vector states, or via two-photon processes, ISR, B-decay, double charmonium. Good mass and width resolution for the vector states. For the other states modest resolutions (detector-limited). In general, the measurement of sub-MeV widths not possible in e + e -.  pp annihilation Direct formation possible for all quantum numbers. Excellent measurement of masses and widths for all states, given by beam energy resolution and not detector-limitedExcellent measurement of masses and widths for all states, given by beam energy resolution and not detector-limited.

D. Bettoni -  PANDA at GSI 12 Experimental Method in  pp Annihilation The cross section for the process:  pp  cc  final state is given by the Breit-Wigner formula: The production rate is a convolution of the BW cross section and the beam energy distribution function f(E,  E): The resonance mass M R, total width  R and product of branching ratios into the initial and final state B in B out can be extracted by measuring the formation rate for that resonance as a function of the cm energy E.

D. Bettoni -  PANDA at GSI 13 The c  c spectrum Ted Barnes

D. Bettoni -  PANDA at GSI 14 Charmonium Physics Program from CDR and TPR Below D  D threshold –Measurement of  C (1S) mass and total width –Discovery/measurement of  C (2S) –h C (1 1 P 1 ) confirmation/measurement (mass, width, decays,...) –Angular distributions in the radiative decays of the  C states. Above D  D threshold –higher vector states –(narrow) D states –radial excitations of P states

D. Bettoni -  PANDA at GSI 15 The  c (1 1 S 0 ) Mass and Total Width M(  c ) =  1.2 MeV/c 2  (  c ) = 17.3  2.6 MeV

D. Bettoni -  PANDA at GSI 16 Recent Discoveries in Charmonium Discovery of the  c (2 1 S 0 ) by Belle (+BaBar, CLEO). Small splitting from . OK when coupled channel effects included. Discovery of new narrow state(s) above D  D threshold X(3872) at Belle (+ CDF, D0, BaBar). M(  c ) =  4.4 MeV/c 2  c cc M =  0.6  0.5 MeV/c 2  2.3 MeV (90 % C.L.) What is the X(3872) ?  Charmonium 1 3 D 2 or 1 3 D 3.  D 0 D 0 * molecule.  Charmonium hybrid (c  cg).

D. Bettoni -  PANDA at GSI 17 More New States above D  D threshold New state discovered by Belle in the hadronic decays of the B- meson: B  K (  J/  )  K(  +  -  0J/  ) New state discovered by BaBar in ISR events: e+e-  Y   (  +  -J/  )  M = 3943  11 MeV/c 2  = 87  22 MeV M = 4259  MeV/c 2  = 88  MeV Y(3940) Y(4260)

D. Bettoni -  PANDA at GSI 18 Charmonium States above the D  D threshold The energy region above the D  D threshold at 3.73 GeV is very poorly known. Yet this region is rich in new physics. The structures and the higher vector states (  (3S),  (4S),  (5S)...) observed by the early e+e- experiments have not all been confirmed by the latest, much more accurate measurements by BES. This is the region where the first radial excitations of the singlet and triplet P states are expected to exist. It is in this region that the narrow D- states occur.

D. Bettoni -  PANDA at GSI 19 Observation of h c ( 1 P 1 ) by E835 and CLEO E835  pp  h c  c  CLEO e + e -  0 h c  c  h c  c   c  hadrons C. Patrignani, BEACH04 presentationA. Tomaradze, QWG04 presentation

D. Bettoni -  PANDA at GSI 20 Charmonium Physics Outlook All 8 states below threshold have been observed. –The study of the h c remains a very high priority in charmonium physics. –The agreement between the various measurements of the  c mass and width is not satisfactory. New, high-precision measurments are needed. The large value of the total width needs to be understood. –The study of the  c has just started. Small splitting from the  must be understood. Width and decay modes must be measured. –The angular distributions in the radiative decay of the triplet P states must be measured with higher accuracy. The energy region above open charm threshold is the most interesting for the future and will have to be explored in great detail: –find all missing states, measure their properties. –explain nature of existing states (X(3872), Y(3940)...) –study radiative and strong decays, e.g.  (4040)  D *  D * and  (4160)  D *  D *, multi amplitude modes which can test the mechanisms of the open-charm decay.

D. Bettoni -  PANDA at GSI 21 The Competition For the near future, new results in charmonium spectroscopy will come from existing e + e - machines: BES at BEPC in Beijing will collect data at the  (3770) resonance CLEO-c at Cornell will run for at least 5 years at the  and especially above threshold. BaBar and Belle at the existing B-factories will continue to provide first rate results in charmonium spectroscopy.

D. Bettoni -  PANDA at GSI 22 Outlook Charmonium physics is experiencing a second youth: the experimental and theoretical scenario changes quickly and it is difficult to predict what the situation will be like after Still we can look forward to a wealth of measurement which can only be done in a precision  pp experiment: The measurement of very narrow widths, which cannot be achieved in e + e -, e.g. the h C and the X(3872). The systematic study of the spectrum, below and above threshold. The systematic study of all decay modes.

D. Bettoni -  PANDA at GSI 23 Charmonium at  PANDA At 2  cm -2 s -1 accumulate 8 pb -1 /day (assuming 50 % overall efficiency)  10 4  10 7 (c  c) states/day. Total integrated luminosity 1.5 fb -1 /year (at 2  cm -2 s -1, assuming 6 months/year data taking). Improvements with respect to Fermilab E760/E835: –Up to ten times higher instantaneous luminosity. –Better beam momentum resolution  p/p = (GSI) vs 2  (FNAL) –Better detector (higher angular coverage, magnetic field, ability to detect hadronic decay modes).

D. Bettoni -  PANDA at GSI 24 Hybrids and Glueballs The QCD spectrum is much richer than that of the quark model as the gluons can also act as hadron components. Glueballs states of pure glue Hybrids q  qg Spin-exotic quantum numbers J PC are powerful signature of gluonic hadrons. In the light meson spectrum exotic states overlap with conventional states. In the c  c meson spectrum the density of states is lower and the exotics can be resolved unambiguously.  1 (1400) and  1 (1600) with J PC =1 -+.  1 (2000) and h 2 (1950)  1 (2000) and h 2 (1950) Narrow state at 1500 MeV/c 2 seen by Crystal Barrel best candidate for glueball ground state (J PC =0 ++ ).

D. Bettoni -  PANDA at GSI 25 Meson Spectrum after LEAR The LEAR Era with the experiments CERN Asterix/Obelix Crystal Barrel Jetset/PS185 WA102/Gams BNL E818/E852 FNAL E760/E835 VES/Gams produced impressive results with high statistics and high resolution

D. Bettoni -  PANDA at GSI 26 Charmonium Hybrids Bag model, flux tube model constituent gluon model and LQCD. Three of the lowest lying c  c hybrids have exotic J PC (0 +-,1 -+,2 +- )  no mixing with nearby c  c states Mass 4.2 – 4.5 GeV/c 2. Charmonium hybrids expected to be much narrower than light hybrids (open charm decays forbidden or suppressed below DD** threshold). Cross sections for formation and production of charmonium hybrids similar to normal c  c states (~ 100 – 150 pb). CLEO   One-gluon exchange Excited gluon flux

D. Bettoni -  PANDA at GSI 27 Charmonium Hybrids Gluon rich process creates gluonic excitation in a direct way –ccbar requires the quarks to annihilate (no rearrangement) –yield comparable to charmonium production 2 complementary techniques –Production (Fixed-Momentum) –Formation (Broad- and Fine-Scans) Momentum range for a survey –p  ~15 GeV

D. Bettoni -  PANDA at GSI 28 Glueballs Detailed predictions of mass spectrum from quenched LQCD. –Width of ground state  100 MeV –Several states predicted below 5 GeV/c 2, some exotic (oddballs) –Exotic heavy glueballs: m(0 +- ) = 4140(50)(200) MeV m(2 +- ) = 4740(70)(230) MeV predicted narrow width Can be either formed directly or produced in  pp annihilation. Some predicted decay modes , , J/ , J/ ... Morningstar und Peardon, PRD60 (1999) Morningstar und Peardon, PRD56 (1997) 4043 The detection of non-exotic glueballs is not trivial, as these states mix with the nearby q  q states with the same quantum numbers, thus modifying the expected decay pattern.

D. Bettoni -  PANDA at GSI 29 Hadrons in Nuclear Matter Partial restoration of chiral symmetry in nuclear matter –Light quarks are sensitive to quark condensate Evidence for mass changes of pions and kaons: –deeply bound pionic atoms –(anti)kaon yield and phase space distribution in pA and AB collisions. (c  c) states are sensitive to gluon condensate –small (5-10 MeV/c 2 ) in medium modifications for low-lying (c  c) (J/ ,  c ) –significant mass shifts for excited states: 40, 100, 140 MeV/c 2 for  cJ,  ’,  (3770) resp. D mesons are the QCD analog of the H-atom. –chiral symmetry to be studied on a single light quark –theoretical calculations disagree in size and sign of mass shift (50 MeV/c 2 attractive – 160 MeV/c 2 repulsive) vacuum nuclear medium  K 25 MeV 100 MeV K+K+ KK   Hayaski, PLB 487 (2000) 96 Morath, Lee, Weise, priv. Comm. DD 50 MeV D D+D+

D. Bettoni -  PANDA at GSI 30 Charmonium in Nuclei Measure J/  and D production cross section in  p annihilation on a series of nuclear targets. J/  nucleus dissociation cross section Lowering of the D + D - mass would allow charmonium states to decay into this channel, thus resulting in a dramatic increase of width  (1D) 20 MeV  40 MeV  (2S).28 MeV  2.7 MeV  Study relative changes of yield and width of the charmonium states. In medium mass reconstructed from dilepton (c  c) or hadronic decays (D)

D. Bettoni -  PANDA at GSI 31 Proton Timelike Form Factors The electromagnetic form factors of the proton in the time-like region can be extracted from the cross section for the process:  pp  e + e - First order QED predicts: Excellent electron identification and background rejection make this measurement possible in  PANDA. The measurement can be carried out in parallel to the spectroscopy program and does not require any special running.

D. Bettoni -  PANDA at GSI 32 Proton Magnetic Form Factor |G M |

D. Bettoni -  PANDA at GSI 33 Form Factor Measurement in  PANDA  PANDA will be able to measure the proton timelike form factors over the widest q 2 range ever covered by a single experiment, from threshold up to q 2 =20-25 GeV 2, and reach the highest q 2. At low q 2 (near threshold) we will be able to measure the form factors with high statistics, measure the angular distribution (and thus G M and G E separately) and confirm the sharp rise of the FF. At the other end of our energy region we will be able to measure the FF at the highest values of q 2 ever reached, GeV 2, which is 2 larger than the maximum value measure by E835. Since the FF decrease ~1/s 5, to get comparable precision to E835 we will need ~80 times more data. In the E835 region we need to gain a factor of at least in data size to be able to measure the electric and magnetic FF separately.

D. Bettoni -  PANDA at GSI 34 The Detector Detector Requirements : –(Nearly) 4  solid angle coverage (partial wave analysis) –High-rate capability (2×10 7 annihilations/s) –Good PID ( , e, µ, , K, p) –Momentum resolution (  1 %) –Vertex reconstruction for D, K 0 s,  –Efficient trigger –Modular design For Charmonium : –Pointlike interaction region –Lepton identification –Excellent calorimetry Energy resolution Sensitivity to low-energy photons

D. Bettoni -  PANDA at GSI 35 Panda Detector (top view)

D. Bettoni -  PANDA at GSI 36 Panda Detector (side view)

D. Bettoni -  PANDA at GSI 37 Preliminary Sharing of Detector Responsibilities Pellet target: GSI, FZ Jülich, TSL Uppsala, Univ. Uppsala. Cluster-jet target: GSI, Univ. Münster, INFN Genova, IMEP Vienna. Nuclear target: FZ Jülich. Micro Vertex Detector: INFN Catania, TU Dresden, Univ. Edimburgh, GSI, FZ Jülich, Univ. Mainz, INFN Torino. Cylindrical tracker (ST/TPC): JINR Dubna, LNF, GSI, FZ Jülich, IMP Lanzhou, TU München, INFN Pavia, Univ. Tübingen, Univ. Uppsala. Particle identification (DIRC-RICH-TOF): JINR Dubna, INFN Ferrara, Univ. Giessen, Univ. Glasgow, GSI, FZ Jülich, IMEP Vienna. Electromagnetic calorimeter: Univ. Bochum, Univ. Giessen, GSI, KVI Groningen, FZ Jülich, IMP Lanzhou, Univ. Mainz, Univ. Minsk, TU München, Univ. Stockholm, Univ. Uppsala, SINS Warsaw, Warsaw Univ. Of Technology. Magnets (Solenoid, Dipole): Univ. Cracow, JINR Dubna, INFN Genova, Univ. Glasgow, IMP Lanzhou. Muon chambers: JINR Dubna, GSI, INFN Torino. Forward Spectrometer: Univ. Cracow, IHEP Protvino, JINR Dubna. Germanium detectors: INFN Catania, INFN Torino, Univ. Mainz, KTH Stockholm. DAQ Trigger Front-end-electronics: Univ. Cracow, Univ. Giessen, GSI, FZ Jülich, Univ. Katowice, INFN Milano, TU München, INFN Torino, SINS Warsaw.

D. Bettoni -  PANDA at GSI 38 Anno Missioni interne Missioni estere Materiali di Consumo Materiale Inventariabile Totale Piano di Spesa R&D CSN3 Settembre 2005

D. Bettoni -  PANDA at GSI 39 RivelatoreCosto [M€]Anno Solenoide SC Dipolo (2Tm) Totale6.3 Meccanica straw tube Rivelatori di vertice Rivelatori al Ge Rivelatore tof a fibre Rivelatori di muoni prot. elett Totale1.6 Bersaglio Costruzione straw tube Rivelatori di vertice Rivelatori al Ge Rivelatore tof a fibre Rivelatori di mouni elettronica read- out Totale2.35 Bersaglio Elettronica straw tube Rivelatori di vertice Rivelatori al Ge Rivelatore tof a fibre Sistema DAQ Totale2.25 Gran Totale12.5 Piano di Spesa Costruzioni

D. Bettoni -  PANDA at GSI 40 Timeline 2003 (Feb 05)GSI upgrade approved by German Govmt.  PANDA part of approved project (March)  PANDA collaboration is formed (Jan 15)Letter of Intent submitted (March)Letter of Intent approved by the QCD-PAC (Jan)Technical Progress Report (TPR) submitted (March)Positive evaluation of TPR. R&D begins R&D Detector Construction 2012 Detector commissioning and start of data taking. Data taking lasts > 8 years

D. Bettoni -  PANDA at GSI 41 Conclusions The HESR at the GSI FAIR facility will deliver high-quality  p beams with momenta up to 15 GeV/c (√s  5.5 GeV). This will allow Panda to carry out the following measurements: High resolution charmonium spectroscopy in formation experiments Study of gluonic excitations (glueballs, hybrids) Study of hadrons in nuclear matter Hypernuclear physics Deeply Virtual Compton Scattering and Drell-Yan Hadron Physics has a brilliant future with PANDA at FAIR ! Hadron Physics has a brilliant future with PANDA at FAIR !