Charmed strange mesons (C = S = ±1) Ds+ = cs, Ds− = cs, similarly for Ds∗'s

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  • VI1.126

    Meson Full Listings D3(24r0) ,

    I I I(JP) : }(7?) D-)(2470) /needs confirmation. OMITTED FROM SUMMARY TABLE

    Seen in D0rr +.

    D~(2470) MASS

    VALUE (MeV) DOCUMENT ID TEEN COMMENT

    246946 ALBRECHT 89F ARG e "~ e - ~ DO ~r~ X

    D~(2470) + - D~(2460) MASS DIFFERENCE

    VALUE (MeV) DOCUMENT IO TECN COMMENT

    145-E8 ALBRECHT 89E ARG e ~ e - - D O ,~+ X

    D~(2470) + DECAY MODES

    D~(2470) modes are charge conjugates of the modes below.

    Mode Fraction (F i /F )

    F 1 DO ~" + seen

    three-pion Dalitz plot by E691 and confirmed by Mark III.

    The f0rc mode is predicted by the weak spectator decay as the

    f0 is believed to be the scalar with hidden strangeness below

    KK threshold. The evidence for the qrc and q~rc modes is still

    controversial. A previous Mark II measurement reported a rate

    relative to 0re of 3.0 1.1 and 4.8 :t: 2.1 l for these modes

    respectively. Recently E691 and Mark III have set upper limits

    whereas NA14 ~ has now seen a very large signal in r/Tr. The

    final answer may lie somewhere in between and will have to

    await more experimental data.

    Table 1. D, Hadronic Decay' Modes

    D~(2470) + BRANCHING RATIOS

    r (D O rr+)/rtotal h/r VALUE DOCUMENT ID TECN COMMENT

    seen ALBRECHT 89F ARG e + e ~ D O rr + X

    D~(2470) REFERENCES

    ALBRECHT 89F PL B231 208 *Glaese~* (ARGUS Collab }

    CHARMED STRANGE MESONS (C= S= +1)

    D + = c~, D~ = Es, similarly for D~'s

    ] D~ [ l(J p) = 0(0 ) was F

    Quantum numbers not measured. Values are assigned here assuming charmed-strange ground state Ds meson, CHEN 83B observations are con- sistent with J = 0. BLAYLOCK 87 observations are consistent with JP = 0 .

    NOTE ON THE D~ DECAYS

    (by W.H. Tok i , SLAC)

    New data on D.~ decays in this edition come from tile

    CLEO, ACCMOR, NAI4': Mark II1, and ARGUS groups.

    This brief note discusses new results in hadronic decays, the

    absolute branching ratios, and the P wave D~ candidates,

    obtained from recent publications, preprints, and summaries. I

    The new D, hadronic modes and recent measurements

    which differ substantially from previous measurenlents are

    listed in Table 1 by' mode. The mode KK*(892) + is analogous

    to the KK + and K*(892)K + modes previously observed and is seen at a comparable rate to that of 0re. The existence of

    these KK decays indicates that tile strength of the internal I.V emission diagrams is sizeable. The O~ rc{I mode is seen only

    ill one experiment, and due to tile linfited statistics, it is not

    possible to deternfine if the decay is through the quasi-two

    body mode Cp0. The f%r mode has now been seen in the

    Decay' Mode F(Mode)/F(D~ -+ Orc ) Group

    KK*(892) ~ 0.890.32 ACCOR 2

    KK*(892) + 1.20:t_2.1 CLEO a

    ore+,@ < 3.5 at 90%CL NAI4 '4

    orc+Tr 2.41.00.5 TPS 5

    ~r%r rc ~r < 3.3 at 90~CL TPS 5

    ~'~' < 0.5 at 90%CL TPS s

    f% 0.28 0.21 + 0.28 TPS 6

    forc 0.58 0.21 0.28 Mark III 7

    q,'r* < 1.5 at 90%CL TPS 5

    q,-r ~ < 2.5 at 90%CL Mark III a

    q'rc- < 1.9 at 90%CL Mark IIIa

    q'~* 6.9 2.4 1.4 NA14 '9

    All branching ratios of the Ds are currently normalized to that of the 0re mode. Therefore knowledge of B(6~r) is required

    to derive the absolute branching ratios of the other modes.

    There are three different approaches to estimate this ratio, all

    from c ( production:

    Tile first ntethod experimentally measures the inclusive rate

    of CE~xp(e -e ~ D~ D, ~ arc) and theoretically determines

    the total D.~ cross section, ath(e+e ~ D~), from estimates of

    the total charm content in R and estimates of the strange sea.

    The absolute branching ratio is then

    B(D~ --+ 07r) = cr~xp(C~ --+ D.~. D~ ~ ~rc) {Tth (eq- C ~ D,)

    The second method from tile CLEO group attempts a

    more precisthe total charm content in R and by measuring all the charm

    baryons and mesons (except tile Ds) and attributing the

    remaining nfissing charln fl'om e+e production to the D,.

    The third method searches for associated production of

    exclusive D., pairs in e~e production into various decay modes near threshold and compares the rate to the inclusive

    D~ production ill the same decay modes. Thus the branching

    ratio for the ore mode is equal to

    B(D~Orc) = a~xP(C+( --D2D~ D2~rc-' D'~Ozc ) a,p(( + e ~ D[ , D~ -- 6rc--)

  • See key on page IV. 1

    This technique, often called the double-tag method, was

    attempted by the Mark III for the Ds but because of limited statistics no events were found and an upper limit was set.

    The first two approaches are model dependent and require

    several theoretical estimates. The last approach is model inde-

    pendent but will require more data to obtain a measurement.

    As the ~r branching ratio drops, we expect that there exist

    many more decays that have not been measured. These miss-

    ing decay modes should contain hidden strangeness and are

    probably attr ibuted to states with high-charged multiplicities

    and/or many neutral secondaries.

    VI1 .127

    Meson Full Listings D~

    11. S. Wasserbaech, unpublished Ph.D. thesis, Stanford Uni- versity, June 1989, see Table 6.1.

    12. W. Chen et el., Phys. Lett. 8226 , 192 (1989). 13. J. Adler et al., Phys. Rev. Lett. 64, 169 (1990). 14. H. Albrecht et al., Phys. Lett. 8230, 163 (1989). 15. P. Avery et al., Phys. Rev. D41, 774 (1990).

    Table 2. Absolute Ds --~ &Tr Branching Ratio Estimates

    Absolute Method B(Ds ~ OTr) Group

    Charm continuum estimate 1.7 - 13% Many groups 11

    All inclusive measurement 2 4- 1% CLEO 12

    Associated production < 4.1 at 90%CL Mark II113

    Table 3. Excited P-Wave D, Candidate

    Decay

    Mode Mass Width Group

    D*+K 2535.9+0.6 4- 2.0 MeV/c 2 < 4.6 MeV/c 2 ARGUS 14

    D*+K 2535.64-0.7 4- 0.4 MeV/c 2 < 5.44 MeV/c 2 CLE@ 5

    D~ MASS

    The fit includes the D E, D 0, D~, and D* . . . . . . . . d the D O - D , D~ - D E ,

    and D~ - Ds ~ mass differences.

    VALUE (MeV) EVT5 DOCUMENT ID TECN CH6 COMMENT 1968.8 0.1 OUR FIT Error includes scale factor of 1.1. 1969.14 1.2 OUR AVERAGE Error includes scale factor of 1.3. See the ideogram

    below. 1 BARLAG 90c CCD n - Cu 230 I

    2 ALBRECHT 88 ARG F -~ ev I 9.4-10.6 GeV

    3 ANJOS 88 SILl Photoproduc- I tion

    BECKER 87B SILl 200 GeV rc,K,p

    BLAYLOCK 87 MRK3 F~em = 4.14 GeV

    USHIDA 86 EMUL u wideband DERRICK 85B HRS F.~e= 29

    GeV AIHARA 84D TPC E~ e = 29

    GeV ALTHOFF 84 TASS F~em = 14-25

    GeV CHEN 83c CLEO E~ e = 10.5

    GeV data for averages, fits, limits, etc.

    ALBRECHT 85D ARG F~ e = 10 GeV

    BAILEY 84 SILl hadron + Be ~r+X

    4 ATKINSON 83 OMEG "rP 5 ASTON 81 OMEG -t- 7P

    ASTON 818 OMEG 7P AMMAR 80 HYBR -I- v wideband USHIDA 808 EMUL - FNAL u wide-

    band USHIDA 80s EMUL + FNAL v wide-

    band BRANDELIK 79 DASP E~em=4.42

    GeV BRANDELIK 77B DASP In BRANDE-

    LIK 79 1BARLAG 90C use 54 DS + ~ K + K ~+ decays. | 2ALBRECHT 88 calculate their mass using the ARGUS value of re(DO) = 1864.1 E 1.4

    I MeV which is 0.5 MeV lower than the world average. 3ANJOS 88 enters fit via the D~ - D E mass difference (see below). Their mass value is 1968.3 0.7 E 0.7 MeV, 4ATKINSON 83 mass error includes systematic uncertainties. 5 Error quoted by ASTON 81 is 10 MeV statistical and

  • VI I .128

    Meson Full Listings

    D~-= - D MASS DIFFERENCE

    VALUE (MeV} EVT5 DOCUMENT ID TEEN COMMENT 99.50.6 OUR FIT Error includes scale factor of 1.1. 99.50.7 OUR AVERAGE 9851.5 555 CHEN 89 CLEO E~e= 10.5 GeV 99.80 8 290 ANJOS 88 SILl Photoproduction

    D~ MEAN LIFE

    VALUE (io 13 s l EVT5 DOCUMENT ID TEEN CH6 COMMENT

    4 a~+0.35 OUR AVERAGE "~- 0.29

    ~Q+l.02 54 6 BARLAG 90C CCD ~r Cu 230 GeV 4 .~ _. 0.86

    3.1 +2.4 0.5 AVERILL 89 HRS Eceem= 29 GeV 2.0

    5.6 +1.3 08 ALBRECHT 881 ARG Ecee= 10 GeV 1.2 47 0.4 02 230 RAAB 88 SILl Photoproduction

    33 + 10 21 7 BECKER 87~ SILl 200 GeV =,K,p 0.6

    5.7 +3.6 0.9 9 BRAUNSCH... 87 TASS F.~em = 35 44 GeM 2.6 4.7 22 =05 141 CSORNA 87 CLEO F_~em = i0 GeV

    3.5 ~2.4 09 17 JUNG 88 HRS + e+e --- o~r+X 1.8

    26 +1.6 6 USHIDA 86 EMUL u wideband -0.9 We do not use the following data for averages, fits, limits, etc.

    4.8 +0.6 t02 99 ANJO5 87B SILl Repl. by 0 .5 RAAB 88 3.2 ~ 30 3 BAILEY 84 SILl hadron Be

    1.3 ~+X

    1.9 f 1,3 4 USHIDA 83 EMUL Repl. by -07 USHIDA 86

    1.4 1 AMMAR 80 HYBR + u wideband

    2 ~+2.78 2 USHIDA 80B EMUL z, wideband ""~ 1.05

    6 BARLAG 90c estimate systematic error to be negligible. 7 BECKER 87B say systematic error was negligible.

    D + DECAY MODES

    D s modes are charge conjugates of the modes below.

    Values are all based on rough estimate of Ds ~ to total charm production. Only ratios of each fraction to the @~+ mode are well known.

    Mode Fraction ( r i / r ) Confidence level

    F 1 d,Tr -t

    F 2 ~z+ 7r+ 7r F 3 p0T,+

    F 4 K0~T +

    F5 KOK+

    F 6 K* (892)0K

    F7 K* (892) +~0

    F 8 K +K ~+ (non-resonant) r 9 K~K ~T*~T 7r+ (non-res.)

    F10 I~ + I/

    F l l ~/=+ F12 Uz+ Tr+/r F13 ~/(958)7r~ ~ +Tr F14 ~p+ F15 n'(958)~ + Ft6 f0(975) 7r+ F17 7r+Tr 7r +

    r18 "rr+~ ~+ (non resonant)

    F19 rr +~ f r+~ ~+ 1-20 /r +/1- /r + ~-0

    1-21 ~,~r* 1-22 ~ ,.1. + ~0

    F23 K+K -r+~r 0 (non-d,)

    1-24 t/ anyth ing

    (2.70.7) %

    (1.30.6) % 2.1 x 10 -3 90%

    6 x 10 3 90%

    (2.6 0.8} %

    (2.60.7) %

    (3.21.1) % (6.72.9) x 10 -3

    9 x 10 3 90%

    3 % 4 % 90%

    possibly seen

    possibly seen

    possibly seen

    seen

    (7.53.4) x 10 3

    (1,20.4) % (7,83.2) x 10 3

    < 8 10 -3 90%

    < 9 % 90%

    < 1.3 % 90%

    (6.4 :~ 3.4) %

    < 6 % 90%

    D + BRANCHING RATIOS

    r (~,~+)/1-total r l / r VALUE ~ EVT5 DOCUMENT ID TECN COMMENT

    0.027:0.007 OUR AVERAGE

  • See key on page IV.1

    VI1,129

    Meson Full Listings D~, D s

    r (n'(958)~r%r+ ~-)/rtotau r13/r VALUE EVT5 DOCUMENT ID TE~N COMMENT possibly seen OUR EVALUAT ION

    We do not use the following data for averages, fits. limits, etc. i

    60 ASTON 81 OMEG ,-fp

    r (@p+)/rtotai F14/r WALUE EVTS DOCUMENT ID TEEN COMMENT possibly seen OUR EVALUAT ION

    We do not use the following data for averages, fits, limits, etc. i

    83 ASTON 81B OMEG ~fp

    r(v'(958)~r+)/r(~ +) rls/rl W~LUE DOCUMENT g D TECN COMMENT

    seen 13WORMSER 88 MRK2 F .~e=29GeV I

    13The ~t%r+ decay mode is observed with a branching ratio of about 5 times B(Ds ~ I ~+).

    r(~ +lr- ~+)/r(~+) FIT/F1 VALUE DOCUMENT IO TEEN COMMENT

    0.44+0.10+0.04 ANJOS 89 TPS Photoproduction

    r(Tr+Tr-Tr + (non-resenant))/r(~Tr +) rzs/rz VALUE DOCUMENT ID TECN COMMENT

    0.29+0.09+0.03 ANJOS 89 TPS Photoproduction

    r ( f0 (975)Tr+) I r (~ +) r l01r l V4LUE DOCUMENT ID TECN COMMENT

    0.280.10:1:0.03 ANJOS 89 TPS Photoproduction

    r (~+ ~- ~+ ~- ~+)/r (~+) r19/rl VdLUE ~ DOCUMENT ID TECN COMMENT

  • V11.130

    Meson Full Listings Ds1(2536) , D~j(2564) , Bottom Mesons

    I(J P) = 0(1 +) /, J, P need confirmation,

    Seen in D*(2010)+K O. Not seen in D + K O. JP = 1 assignment strongly favored.

    Ds1(2536) MASS

    VALUE (MeV~ DOCUMENT ID TECN COMMENT 2536.5=t= 0.8 OUR AVERAGE

    2536.6 0.70.4 AVERY 90 CLEO e + e ~ D *+ K 0 X

    2535.9 0 .920 ALBRECHT 89E ARG Dsl ~ D*(2OIO)K O

    2535 28 1 ASRATYAN 88 HLBC u N ~ Ds~,? X

    1 Not seen in D* K.

    Ds1(2536) :t: - D~(2111) MASS DIFFERENCE

    VALUE (MeV] DOCUMENT ID TECN COMMENT

    42428 ASRATYAN 88 HLBC D~ ~,

    Ds1(2536) WIDTH

    VALUE (MeV) CL~/o DOCUMENT 10