new spectroscopy with panda @ fair · 2015-09-18 · 1st of its kind accepted reference magnet for...

New spectroscopy with PANDA @ FAIR:X, Y, Z, and the F-wave charmonium states

September 18th, 2015 | Elisabetta Prencipe, Forschungszentrum Jülich | HADRON 2015 – Newport News (VA)

on behalf of the PANDA Collaboration.

Outline

E. Prencipe HADRON Conference, 13-18 Sept 2015

2

Introduction

PANDA physics program

The detector PANDA @ FAIR

Evaluation of X, Y, Z rates in pp annihilation

X, Y, Z searches at PANDA

F-wave charmonium state search Summary

The physics case

Understanding of confinementOrigin of hadron masses

through the study of

Hadron spectroscopy - Search for gluonic excitations - Charmonium spectroscopy - D meson spectroscopy - Baryon spectroscopy - QDC dynamics

Nucleon structure - Parton distributions - Time-like form factors of the proton - Transition distribution amplitudes - Generalized distribution amplitudes

Hadrons in matter Hypernuclei


3


13 m

Pre-assembling at COSY, Jülich


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2T solenoid magnet 2Tm dipole magnet

Magnet system


5

Magnets (Tendering by FAIR)

Dipoles:

May 2015: 1st dipole in Jülich

Delivery of last dipole (46) expected for Q2/2017

1st of its kind ready and measured in January 2015Series production releasedDipole is reference magnet for all following dipoles

1st magnet arrived in Jülich middle of May this yearNow 7 dipoles in JülichEvery 2 weeks one dipole is expected to be deliveredMounting of vacuum chambers in JülichStorage until building is ready

The detector PANDA @ FAIRCourtesy of Dieter Prasuhn


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Quadrupoles:

Delivery of last quadrupole (84) expected Q2/2017

1st of its kind accepted Reference magnet for the next magnets

2 quadrupoles have arrived in Jülich, 3rd is expected to arrive in Jülich this week

In Jülich mounting of the complete units

Sextupole – Quadrupole – Steerer planned

The detector PANDA @ FAIRCourtesy of Dieter Prasuhn


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Interaction pointAnti protonbeam

Cluster jet- or Pellet-Target

Target system: TDR approved for cluster jet Prototype under construction

Pellet target in operation at WASA-at-Cosy (FZJ)

Cluster jetprototype


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Micro Vertex Detector

Straw Tube Tracker

Forward Tracking System

Luminosity Monitor

GEM Detector

Design ongoing

TDR approved

Tracking system

Square-strip sensor prototypeTDR approved


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Barrel TOF Barrel DIRC Endcap DIRC Forward TOF

Forward RICH

Muon Detectors

Muon Range System

PID system


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PbWO4 Calorimeter

Forward Shashlyk EMC

Calorimeters: All endcap crystals producedTDR approved


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The detector PANDA @ FAIRPANDA is a fixed target detector

s up to 5.5 GeV High boost β

cms ≥ 0.8

Many tracks and photons in fwd acceptance ( θ ≤30°) (high p

z, E

γ)

High background from hadronic reactions

Expected S/B ~ 10−6

S (signal) and B (background) have same signature Hardware trigger not possible Self-triggered electronics Free streaming data 20 MHz interaction rate Complete real-time event reconstruction


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HESR with PANDA

Beam life time >30 minThick target: 4 ⋅1015 cm-2


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Circumference

Magnetic rigidity

Maximum dipole

Dipole at injection

Dipole ramp

574 m

5- 50 Tm

1.7 T

0.4 T

0.025 Tm

2 possible operational modes:

High resolution mode High intensity mode

e− cooling, 1.5≤ p≤ 8.9 GeV/c

1010 antiprotons storedLuminosity up to 2 ⋅1031 cm−2 s−1

∆p/p = 510-5

Stochastic cooling, p≥ 1.5 GeV/c

1011 antiprotons storedLuminosity up to 2 ⋅1032 cm−2 s−1

∆p/p = 110-4

Why antiprotons in PANDA?

In production: all quantum numbers accessible in pp reactions

High mass / width resolution in formation

High angular momentum accessible

Resonance scan technique:invariant mass resolution dependson the beam resolution

PANDA is in an unique position toperform such a study! Charm and Charmonium resonance mass scan

Annihilation is a gluon rich process


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How PANDA can give an original contribution?

Examples from Charmonium Spectroscopy with PandaRoot simulations will be shown

PandaRoot = Root-based framework developed inside the FairRoot project, for FAIR experiments and PANDA

D. Bertini, M. A-Turany, I. Koenig and F. Uhlig , Journal of Physics: Conference Series 119 (2008) 032011S. Spataro, Journal of Physics: Conference Series 396 (2012) 022048


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Charmonium(-like) spectrum, today

Since 2003 the charmonium(-like) spectrumappeared to be richer than expected

Observation of states which do not fit theoretical models and predictions

The case of X(3872): isospin violating, very narrow, known quantumnumbers (LHCb), still unclear nature. Need to measure its width

States with high angular momentum:- predicted in potential models (J>3):

- need to be verified to confirm theory - production suppressed at B factories - possible search in PANDA. - mass prediction by Barnes, Godfrey, Swanson, PRD 72 (2005) 054026: 13F

4 state, m∈[4.021; 4.095] MeV/c2, Γ=8.3 MeV

courtesy of R. Mitchel


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X, Y, Z cross sections at PANDA

for non polarized incident beam.

If BR(R pp) is known (from PDG), (X, Y, Z pp) use the detailed balance method

If BR(R pp) is unknown (from PDG), (X, Y, Z pp) evaluate BR(R pp) by scaling widths, then use detailed balance method

Assumption: partial width of charmonium states are identical

Detailed balance method:

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Reference resonance for our calculation: (3770)

How do we know that this method works?


(See back up slides for details)

Detailed balance method

J/ '

Detailed balance method: check on E760 data


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M. Galuska M. Galuska

X(3872) cross section at PANDA

X(3872) cross section


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X(3872) cross section at PANDA

X(3872) cross section Use detailed balance and PDG measured BRs


From LHCb: EPJ C(73) (2013) 2462

5% [PRL 112 (2014) 092001]

An upper limit is calculated.Reasonable value: 50 nb

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Y(4260) cross section at PANDAY(4260) cross section

Upper limit:

Lower limit:


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Detailedbalance this UL leads to unrealistic high cross section estimate: 4370 nb

BR(Y(4260) pp) / BR(Y(4260) J/) <0.13 @ 90% c.l.

Reference resonance for scaling: (3770)Values taken from PDG

BR((3770) pp) = (7.1 )10-6

(pp (3770)) = (9.8 ) nb

+ 8.6

2.9+ 11.89

use scaling approach

BR(Y(4260) pp)) = BR((3770) pp)

total ((3770))

total

(Y(4260))

(pp Y(4260)) = (pp (3770))

total ((3770))

total

(Y(4260))= 9.8 nb = 2.2 nb

27.2 MeV102 MeV

(pp Y(4260)) = 2.2 nb

ee (Y(4260))

ee

((3770))= 2.2 nb

ee

(Y(4260))

BR(3770) e+etotal

((3770))

= 0.077 nb

Y(4260) naively treated as a charmonium state: no model for exotics fix a range (educated guess)

Z(3900)+ cross section at PANDA


Z(3900) cross section

PRL 112 (2014) 092001

BES III @ 4.26 GeV

Upper limit, using our(Y(4260)) upper limit

Lower limit, using our(Y(4260)) upper limit

Assumptions: - Non-resonant Y(4260) J/ contribution negligible; - BR(Y(4260) J/ ) = 100% (no significant evidence of other channels reported in the PDG, except Y X) 22

X, Y, Z rates at PANDA

How many X(3872), Y(4260), Z(3900)+ can PANDA produce?

pb-1/day

pb-1/day

Upper limit

Lower limit


Resonance Cross section (nb)

X(3872)

Y(4260)

Z(3900)+

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[0.077 – 2.2]

[0.017 – 0.473]

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Challenge: measurement of X(3872) width

Goal: measure the width of X(3872), to disclose its natureIn PANDA: mass resolution 20x times better than B factories (challenge: 50-100 keV)[PDG upper limit: Γ<1.2 MeV @ 90% c.l.]

M. Galuskamaster thesis2011

Pos (Bormio 2012) 18


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Challenge: high angular momentum states

Search for additional states as test of flavour independence

3F4 state predicted, never seen

Suppressed production in BES III, Belle IIPANDA can perform this search


arXiV:1311.7597 [hep-ex], CHARM2013

S. Reiterbachelor thesis2012

S. Lange

Challenge: interference effect in rare decays

J/ψe+e−

BR∼6%

Y(4260) e+e−

BR(expect.)

≤ 10−6

BaBar, PRD 86 (2012) 051102

ℬ(J/ψπ+π−) x ℬ(e+e−) = (9.2±0.8) eV

Resonance BR(ψ→e+e−) Γ/MeVψ(3770)

ψ(4040)

ψ(4160)

ψ(4415)

27.2±1.080±10

103±862±20

(9.6± 0.7)×10−6

(1.07± 0.16)×10−5

(8.1± 0.9)×10−6

(9.4± 3.2)×10−6

PANDA: mini-Y(4260) factory.

Y(4260) e+e− not observed, yet: limit from coupling to initial state

Overpopulated 1−− Charmonium spectrumIn PANDA possibility to study rare decays1−− states are large: they can interfere

Mass(e+e−) [GeV/c2]

pp Y(vector state), Y e+e−

arXiV:1410.5201 [hep-ex], ICHEP2014


Exclusive reco: N = 16 000 evts ψ(3770), ψ(4040), Y(4160), Y(4260), ψ(4415), Y(4360), Y(4660) to e+e- p = 9.5 GeV/c ε ~70%

E.P.

3770 4040 4160 4260 4415 4360 4660

Mass(e+e−) [GeVc2]

Expected Z states near DD threshold, never observed (mZ ~ 3730 MeV/c2)

Proposal @ PANDA:

[1]

[2]

[3]

[4]

[5]

[6]

[7]

[1] PRL 100(2008)142001; [2] PRL 110(2013)252001; [3] PLB 727(2013)366; [4] arXiV:1309.1806; [5] ICHEP2014;[6] PRL 112(2014)022001; [7] PRL 112(2014)132001.


Challenge: search for new exotic Z states

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Z workshop 2015, Giessen (DE)

Production forbidden by parity conservation at e+ecolliders

X(3872)Z(3730) transition kinematically allowed(but maybe rare decay and X(3872) statistics limited at e+e colliders)

pp Z(3730)0, Z(3730)0 J/pp Z(3730)0Z(3730)0

c1

pp Z(3730)+Z(3730) c1

c1

J/

Summary

Still many open questions in hadron physics:

a pp machine is neededPrecise measurement of the width of the charmonium(-like) states: the future project PANDA at FAIR will reach high level precision in mass/width evaluation at level never reached before (20x B factories)

High spin particle challenge

Progresses at LHCb and BESIII, after B factory measurements: still not enough to explain the spectrum

High production rateX, Y, Z rates provided: simulation campaign ongoing

Big hardware effort: test beam started, TDRs ongoing

Important contributions expected from PANDA measurements.


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“Genius is 1% talent and 99% hard work”

THANKS!

PANDA Collaboration, >500 physicists, 18 Countries (2014)


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Back up slides


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FAIR - The new Facility for Antiproton and Ion Research in Europe

FAIR is a new, unique international accelerator facility for the research with antiprotons and ions. It is ready to be built within the coming years in Darmstadt, Germany. The major part of the budget will be provided by the Federal Republic of Germany, together with the German State of Hesse. Other fractions will be funded by international partners from Europe and overseas.

The core of FAIR, a double-ring accelerator (SIS100/SIS300 heavy ion synchrotron) with a circumference of 1100 meters, will be associated with a complex system of cooler and storage rings and experimental setups. The synchrotron will deliver ion beams of unprecedent intensities and energies. Thus also intensive secondary beams can be produced, providing antiprotons and exotic nuclei.

FAIR will be built near the premises of the renowned physical research institute GSI Helmholtzzentrum für Schwerionenforschung GmbH. The GSI facility will serve as pre-accelerator and injector for the new complex.

The new FAIR facility, where various physics programs can be operated in parallel, will offer outstanding research opportunities and discovery potential for about 3000 scientists from about 50 countries.

FAIR allows to carry out several physics programs in parallel, covering four major fields:


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NUSTAR: Nuclear Structure, Astrophysics and Reactions

FAIR will create secondary beams of highly unstable nuclei for probing nuclear structure and the origin of the elements in the Universe. FAIR will deliver beams of all kinds of isotopes down to the shortest-lived, in high purity, with a wide range of energies, and in timed pulses tailored for experiments. For the first time, the heaviest unstable nuclei will be produced in large enough quantities for precision studies. They are then directed to three experimental areas: The high-energy branch where reactions of high-energy heavy nuclei relevant to astrophysical processes will be investigated; The low-energy branch where properties of nuclei such as decay modes and energy levels can be explored using low-energy beams; The ring branch where exotic nuclei are collected, cooled and stored in the FAIR ring system (CR-RESR-NESR). There, experiments will measure the masses and lifetimes of unknown nuclei or probe their structure using an electron or antiproton beam.

CBM: Compressed Baryonic Matter

High-energy collisions between heavy nuclei will be carried out at FAIR to investigate how nuclear matter behaves over a range of high pressures typically found in supernova explosions and neutron stars. At very high densities, we expect the constituents of atomic nuclei, the protons and neutrons, to ‘melt’ into a quark-gluon plasma. This phase transition to such a new state shall be observable in violent collisions between nuclei at energies provided by the FAIR accelerators. A universal detection system will identify the particles that are created in the dense reaction zone, for example, particles containing strange and charm quarks which serve as sensitive diagnostic probes. The experiments at FAIR will complement studies of the more primordial hot quark-gluon plasma state being carried out with the Large Hadron Collider (LHC) at CERN in Geneva.


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PANDA: AntiProton ANnihilation at DArmstadt

Antiproton beams of unprecedented intensity and quality will be produced at FAIR. They are made by bombarding a target with protons, cooled in the two cooler rings (CR and RESR) and then stored in the High Energy Storage Ring (HESR). There, they interact with a proton target (hydrogen) to produce a variety of composite particles containing strange and charm quarks. In particular, one particle consisting of a charm quark and antiquark – charmonium – will probe aspects of the strong force not investigated before. The interaction region is enclosed by the multipurpose PANDA detector. This is composed of layers of different kinds of detecting devices to track the paths and measure the energies of particles produced by the antiproton-target collisions.

APPA: Physics - Atomic, Plasma Physics and Applications

Matter plasmas may occur in various forms. Hot plasmas at low pressure are already well-known. But still less investigated are plasmas at high pressure and low temeratures as they exist e.g. in the interior of large planets. Plasma physics experiments at FAIR will reveal latest findings in this field. The heavy ions available at FAIR will also be used to investigate the impact of cosmic radiation on inter-planetary flights for both, astronauts and spacecraft components. Ultra-strong electromagnetic fields occur in highly-charged heavy ions and can be further increased in experiments with fast heavy ions passing each other. The new project will open up unique opportunities for research in these areas of ultra-strong field physics testing the quantum-dynamic theory.


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Facility for Antiproton and Ion Research

Scientific pillars of FAIR:1. Atomic, Plasma Physics and Applications – APPA2. Compressed Baryonic Matter – CBM3. NUclear STructure, Astrophysics and Reactors – NUSTAR4. antiProtons ANnihilation at DArmstadt - PANDA

3000 Physicists50 Countries

PANDA NUSTAR

APPA CBM


QCD in a nutshell

The modern theory of strong interactions is the Quantum Chromo Dynamics (QCD) - QCD is the quantum field theory of quarks and gluons - It is based on the non-abelian gauge group SU(3) - It is part of the Standard Model

At high energy QCD is well tested - The coupling constant α

s becomes small at high energy

- Perturbation theory applies

At low energy, QCD is still to be understood - Several theoretical approaches: Potential models Lattice QCD (LQCD) Effective field theory (EFT) ....

Input from experimental physics - Several experimental techniques

PDG 2012


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Goal of DS spectroscopy studies

width of the DsJ

states

Reconstruct the excitation function of the cross sectionScan every 100-200 keV around the mass peak is required (only PANDA can do that!)

Advantage in PANDA: very high statisticshigh mass resolution

Main problem: high level of background, signal and bkg have same signature.Kinematic fit needed: several options in PandaRoot in this momentGood vertex resolution is needed

Challenge: slow pions; need of a good tracking for low momentum tracks


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Search for suppressed high J states

Courtesy of S. Lange, Charm2013

37

Cross section estimated (PANDA)


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Physics reason for scaling

J/

'

e.m. process:

hadronic process:

Wave functions: solution of the Schrödinger equation for pure charmonium statesPartial width for annihilation scales with |(r=0)|2

assumption: same partial width for charmonium states in our calculation


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PANDA pellet target proposal (I)

beam No beam

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PANDA pellet target proposal (II)Courtesy of E. Koehelr, A. Khoucaz


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PANDA MVD


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PANDA STT


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PANDA DIRC


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PANDA DIRC


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PANDA Muon detector


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PANDA calorimeter

Barrel Calorimeter11360 PbWO

4 Crystals

LAAPD readout, 2x1 cm2

σ(E)/E ~ `.5% E = const

Forward Calorimeter3600 PbWO

4 Crystals

High occupancy in centerLAAPD or VPT

Backward endcap524 PbWO

4 Crystals

Crystal length: 20 cm = 22X0

Increase of light yield: - PbWO II~x2 CMS PbWO

4 Crystals

- Operation with 2 APDs (1 cm2 each) increase effic. ~ x4 compared to CMS - Operation at -25 °C increases light yield compared to +18 °C ~x4 times big improvement compared to CMS


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PANDA calorimeter

Operated at -25 °C

Courtesy of R. Novotny


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PANDAROOT status


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new spectroscopy with panda @ fair · 2015-09-18 · 1st of its kind accepted reference magnet for...

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