d sj (2700) in decay j.brodzicka, h.palka inp krak ó w dc june 12 , 2006

DDsJsJ(2700)(2700) in in decay decay

J.Brodzicka, H.Palka INP KrakJ.Brodzicka, H.Palka INP KrakóówwDC DC JuneJune 1212, 2006, 2006

BB++ D D00DD00KK++

How to describe M(D0K+) distribution?How to describe M(D0K+) distribution?

J.Brodzicka, H.Palka INP J.Brodzicka, H.Palka INP DCDC JuneJune 1212, 2006, 2006

M(D0K+) for M(D0D0)>3.85GeV to remove (3770) reflection from high M(D0K+) region

BW + MC predicted (4160) reflection + non-resonant component described by 3-body MC

3-body PS3-body PS: 47 ± 32: 47 ± 32

previous fit: previous fit: now: now: + scalar exponential component+ scalar exponential component


M(D0K+) M(D0K+) corrected for acceptancecorrected for acceptance

Fit: BW + MC predicted (4160) reflection+ exp[-A * M(D0K+) ] + non-resonant component described by 3-body MC

Physics interpretation of this exponential component?


Contribution from each component:normalized to measured yield and superimposed by adding histograms – non coherent approach

Explanation ofExplanation of eff. correctedeff. corrected 2-body mass spectra2-body mass spectra

Shapes predicted by MC simulations B+ (4160) K+B+ (3770) K+

B+ D0

DsJ+(2700)exp. component


Explanation ofExplanation of 2-body mass spectra2-body mass spectra

Shapes predicted by MC simulations B+ (4160) K+B+ (3770) K+

B+ D0

DsJ+(2700)exp. component


MC studies based on the relative intensities of contributing components obtained from data analysis (non coherent approach)

How interference between DsJ(2700) and scalar exp.

component influences the DsJ parametres?

Dalitz plots for various decay models forDalitz plots for various decay models forBB++ D D00DD00KK++

no interference max constructive interf. max destructive interf.

Decay model predictions vs. observed mass spectraDecay model predictions vs. observed mass spectra


non-coherent approach

no interference

max constructive interf.

between DsJ(2700) and exp

max destructive interf.

between DsJ(2700) exp

interference effects do not influence interference effects do not influence DsJ parameters stronglyDsJ parameters strongly decay model is not decideddecay model is not decided (included in systematics) (included in systematics) look at angular distributions is neededlook at angular distributions is needed

for uncorrected distributionsfor uncorrected distributions


no interference max constructive interf. max destructive interf.

BackupsBackups


J.Brodzicka, H.Palka INP BAM February 27th, 2006J.Brodzicka, H.Palka INP BAM February 27th, 2006

Angular distribution Angular distribution in the helicity frame of DsJ(2700)in the helicity frame of DsJ(2700)

fitted B Signalcorrected for acceptance

Comparison with the DsJ(2700) spin hypotheses:

J=1 2/n.d.f = 3.4/4 J=2 2/n.d.f = 16.2/4 J=0 2/n.d.f = 36.5/4

Background-free cos distribution obtained using 2-dim Mbc-E fit in each cos bin

11-- favouredfavoured

DsJ(2700) DsJ(2700) →→DD00KK++ : : 11 →→ 00-- 00-- P-wave P-wave

decaydecay

thusthus DsJ(2700) DsJ(2700) P parity : P parity : --

Contributions from quasi-two-body components:(normalized to measured yields and superimposed by adding histograms)

B+ (4160) K+B+ (3770) K+ B+ D0 DsJ+(2700)

Explanation ofExplanation of 2-body mass spectra2-body mass spectra

Shapes predicted by MC simulations

DDsJsJ++((2702700)0), , ((3773770)0) are not the full story, but the ‘fit’ is acceptable are not the full story, but the ‘fit’ is acceptable


Background-free mass distr. corrected for acceptanceBackground-free mass distr. corrected for acceptance

M(M(DD00DD00) strongly affected by acceptance losses ) strongly affected by acceptance losses influence of these losses on influence of these losses on DDsJsJ(2700(2700) region) region is minor is minor

B+ (4160) K+B+ (3770) K+

B+ D0

DsJ+(2700)

(3770)

DsJ(2700)Z(3930)


Dalitz plot and projections forDalitz plot and projections for Background: elliptical strip 6 to 10

in Mbc, E, surrounding the signal region

B+ D0D0K+

For Mbc > 5.277GeV E<10 MeV

( 1.5 signal region )

LR > 0.01

(4160(4160))

(3770)(3770)

DDsJsJ(2700)(2700)

(3770)(3770) (4160)(4160)

DDsJsJ(2700)(2700)

DDsJsJ(2700) (2700) (3770)(3770)

(4160(4160))

(3770)(3770)(4160(4160))

DDsJsJ(2700)(2700)


Mass distributions corrected for acceptanceMass distributions corrected for acceptance

Events from 1.5 E-Mbc signal region

Background


Dalitz Dalitz plot plot projections projections forforwith smaller 20MeV binningwith smaller 20MeV binning

Background

B+ D0D0K+

For 1.5 E-Mbc signal region

LR > 0.01

for 400fbfor 400fb-1-1

no significant narow states


SummarySummary 400 fb400 fb-1-1 sample has been analysed; sample has been analysed; all features seen in the 250 fball features seen in the 250 fb-1 -1 sample are confirmedsample are confirmed

strong strong DDsJsJ(2700)(2700)→→DD00KK++ resonanceresonance (significance = 6.7(significance = 6.7σσ) )

M= 2709 M= 2709 ±± 10 MeV 10 MeV ΓΓ= 137 = 137 ±± 27 MeV J 27 MeV JPP=1=1-- favoured favoured ΨΨ(3770) confirmed(3770) confirmed M= 3777 M= 3777 ±± 3 MeV 3 MeV ΓΓ= 27 = 27 ±± 9 MeV 9 MeV remaining structures in M(remaining structures in M(DD00DD00) could not be resolved, ) could not be resolved, but their influence on the but their influence on the DDsJsJ(2700)(2700) parameters is small parameters is small (included into systematic errors) (included into systematic errors)

We would like to publish We would like to publish DDsJsJ(2700)(2700) as it is now, as it is now, deeper insight into M(deeper insight into M(DD00DD00) and M() and M(DD00KK++) dynamics ) dynamics will be possible after full Dalitz plot analysis (if it is successful)will be possible after full Dalitz plot analysis (if it is successful)


d sj (2700) in decay j.brodzicka, h.palka inp krak ó w dc june 12 , 2006

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