Search for the rare decays B⁺ -> μ⁺μ⁻K⁺, B⁰ -> μ⁺μ⁻K*(892)⁰, and B_s⁰ -> μ⁺μ⁻ϕ at CDF

Article

Reference

Search for the rare decays B

-> μ

μ

K

, B

-> μ

μ

K*(892)

, and B

-> μ

μ

ϕ at CDF

CDF Collaboration

CLARK, Allan Geoffrey (Collab.), et al .

Abstract

We search for b→sμ+μ− transitions in B meson (B+, B0, or B0s) decays with 924  pb−1 of pp collisions at s√=1.96  TeV collected with the CDF II detector at the Fermilab Tevatron. We find excesses with significances of 4.5, 2.9, and 2.4 standard deviations in the B+→μ+μ−K+, B0→μ+μ−K∗(892)0, and B0s→μ+μ−ϕ decay modes, respectively. Using B→J/ψh (h=K+, K∗(892)0, ϕ) decays as normalization channels, we report branching fractions for the previously observed B+ and B0 decays, B(B+→μ+μ−K+)=(0.59±0.15±0.04)×10−6, and B(B0→μ+μ−K∗(892)0)=(0.81±0.30±0.10)×10−6, where the first uncertainty is statistical, and the second is systematic. We set an upper limit on the relative branching fraction B(B0s→μ+μ−ϕ)/B(B0s→J/ψϕ)

CDF Collaboration, CLARK, Allan Geoffrey (Collab.), et al . Search for the rare decays B

-> μ

μ

−

K

, B

-> μ

μ

K*(892)

, and B

-> μ

μ

ϕ at CDF. Physical Review. D , 2009, vol. 79, no. 01, p.

011104

DOI : 10.1103/PhysRevD.79.011104

Available at:

http://archive-ouverte.unige.ch/unige:38548

Disclaimer: layout of this document may differ from the published version.

1 / 1

Search for the rare decays B

!

K

, B

!

K

ð892Þ

, and B

!

at CDF

T. Aaltonen,²⁴J. Adelman,¹⁴T. Akimoto,⁵⁶M. G. Albrow,¹⁸B. A´ lvarez Gonza´lez,¹²S. Amerio,^44a,44bD. Amidei,³⁵ A. Anastassov,³⁹A. Annovi,²⁰J. Antos,¹⁵G. Apollinari,¹⁸A. Apresyan,⁴⁹T. Arisawa,⁵⁸A. Artikov,¹⁶W. Ashmanskas,¹⁸ A. Attal,⁴A. Aurisano,⁵⁴F. Azfar,⁴³P. Azzurri,^47a,47dW. Badgett,¹⁸A. Barbaro-Galtieri,²⁹V. E. Barnes,⁴⁹B. A. Barnett,²⁶ V. Bartsch,³¹G. Bauer,³³P.-H. Beauchemin,³⁴F. Bedeschi,^47aP. Bednar,¹⁵D. Beecher,³¹S. Behari,²⁶G. Bellettini,^47a,47b

J. Bellinger,⁶⁰D. Benjamin,¹⁷A. Beretvas,¹⁸J. Beringer,²⁹A. Bhatti,⁵¹M. Binkley,¹⁸D. Bisello,^44a,44bI. Bizjak,³¹ R. E. Blair,²C. Blocker,⁷B. Blumenfeld,²⁶A. Bocci,¹⁷A. Bodek,⁵⁰V. Boisvert,⁵⁰G. Bolla,⁴⁹D. Bortoletto,⁴⁹ J. Boudreau,⁴⁸A. Boveia,¹¹B. Brau,¹¹A. Bridgeman,²⁵L. Brigliadori,^44aC. Bromberg,³⁶E. Brubaker,¹⁴J. Budagov,¹⁶

H. S. Budd,⁵⁰S. Budd,²⁵K. Burkett,¹⁸G. Busetto,^44a,44bP. Bussey,^22,rA. Buzatu,³⁴K. L. Byrum,²S. Cabrera,^17,q C. Calancha,³²M. Campanelli,³⁶M. Campbell,³⁵F. Canelli,¹⁸A. Canepa,⁴⁶D. Carlsmith,⁶⁰R. Carosi,^47aS. Carrillo,^19,k

S. Carron,³⁴B. Casal,¹²M. Casarsa,¹⁸A. Castro,^6a,6bP. Catastini,^47a,47cD. Cauz,^55a,55bV. Cavaliere,^47a,47c M. Cavalli-Sforza,⁴A. Cerri,²⁹L. Cerrito,^31,oS. H. Chang,²⁸Y. C. Chen,¹M. Chertok,⁸G. Chiarelli,^47aG. Chlachidze,¹⁸

F. Chlebana,¹⁸K. Cho,²⁸D. Chokheli,¹⁶J. P. Chou,²³G. Choudalakis,³³S. H. Chuang,⁵³K. Chung,¹³W. H. Chung,⁶⁰ Y. S. Chung,⁵⁰C. I. Ciobanu,⁴⁵M. A. Ciocci,^47a,47cA. Clark,²¹D. Clark,⁷G. Compostella,^44aM. E. Convery,¹⁸J. Conway,⁸

K. Copic,³⁵M. Cordelli,²⁰G. Cortiana,^44a,44bD. J. Cox,⁸F. Crescioli,^47a,47bC. Cuenca Almenar,^8,qJ. Cuevas,^12,n R. Culbertson,¹⁸J. C. Cully,³⁵D. Dagenhart,¹⁸M. Datta,¹⁸T. Davies,²²P. de Barbaro,⁵⁰S. De Cecco,^52aA. Deisher,²⁹

G. De Lorenzo,⁴M. Dell’Orso,^47a,47bC. Deluca,⁴L. Demortier,⁵¹J. Deng,¹⁷M. Deninno,^6aP. F. Derwent,¹⁸ G. P. di Giovanni,⁴⁵C. Dionisi,^52a,52bB. Di Ruzza,^55a,55bJ. R. Dittmann,⁵M. D’Onofrio,⁴S. Donati,^47a,47bP. Dong,⁹

J. Donini,^44aT. Dorigo,^44aS. Dube,⁵³J. Efron,⁴⁰A. Elagin,⁵⁴R. Erbacher,⁸D. Errede,²⁵S. Errede,²⁵R. Eusebi,¹⁸ H. C. Fang,²⁹S. Farrington,⁴³W. T. Fedorko,¹⁴R. G. Feild,⁶¹M. Feindt,²⁷J. P. Fernandez,³²C. Ferrazza,^47a,47dR. Field,¹⁹

G. Flanagan,⁴⁹R. Forrest,⁸M. Franklin,²³J. C. Freeman,¹⁸I. Furic,¹⁹M. Gallinaro,^52aJ. Galyardt,¹³F. Garberson,¹¹ J. E. Garcia,^47aA. F. Garfinkel,⁴⁹K. Genser,¹⁸H. Gerberich,²⁵D. Gerdes,³⁵A. Gessler,²⁷S. Giagu,^52a,52b V. Giakoumopoulou,³P. Giannetti,^47aK. Gibson,⁴⁸J. L. Gimmell,⁵⁰C. M. Ginsburg,¹⁸N. Giokaris,³M. Giordani,^55a,55b

P. Giromini,²⁰M. Giunta,^47a,47bG. Giurgiu,²⁶V. Glagolev,¹⁶D. Glenzinski,¹⁸M. Gold,³⁸N. Goldschmidt,¹⁹ A. Golossanov,¹⁸G. Gomez,¹²G. Gomez-Ceballos,³³M. Goncharov,⁵⁴O. Gonza´lez,³²I. Gorelov,³⁸A. T. Goshaw,¹⁷

K. Goulianos,⁵¹A. Gresele,^44a,44bS. Grinstein,²³C. Grosso-Pilcher,¹⁴R. C. Group,¹⁸U. Grundler,²⁵ J. Guimaraes da Costa,²³Z. Gunay-Unalan,³⁶C. Haber,²⁹K. Hahn,³³S. R. Hahn,¹⁸E. Halkiadakis,⁵³B.-Y. Han,⁵⁰ J. Y. Han,⁵⁰R. Handler,⁶⁰F. Happacher,²⁰K. Hara,⁵⁶D. Hare,⁵³M. Hare,⁵⁷S. Harper,⁴³R. F. Harr,⁵⁹R. M. Harris,¹⁸

M. Hartz,⁴⁸K. Hatakeyama,⁵¹J. Hauser,⁹C. Hays,⁴³M. Heck,²⁷A. Heijboer,⁴⁶B. Heinemann,²⁹J. Heinrich,⁴⁶ C. Henderson,³³M. Herndon,⁶⁰J. Heuser,²⁷S. Hewamanage,⁵D. Hidas,¹⁷C. S. Hill,^11,dD. Hirschbuehl,²⁷A. Hocker,¹⁸

S. Hou,¹M. Houlden,³⁰S.-C. Hsu,¹⁰B. T. Huffman,⁴³R. E. Hughes,⁴⁰U. Husemann,⁶¹J. Huston,³⁶J. Incandela,¹¹ G. Introzzi,^47aM. Iori,^52a,52bA. Ivanov,⁸E. James,¹⁸B. Jayatilaka,¹⁷E. J. Jeon,²⁸M. K. Jha,^6aS. Jindariani,¹⁸W. Johnson,⁸

M. Jones,⁴⁹K. K. Joo,²⁸S. Y. Jun,¹³J. E. Jung,²⁸T. R. Junk,¹⁸T. Kamon,⁵⁴D. Kar,¹⁹P. E. Karchin,⁵⁹Y. Kato,⁴² R. Kephart,¹⁸J. Keung,⁴⁶V. Khotilovich,⁵⁴B. Kilminster,⁴⁰D. H. Kim,²⁸H. S. Kim,²⁸J. E. Kim,²⁸M. J. Kim,²⁰ S. B. Kim,²⁸S. H. Kim,⁵⁶Y. K. Kim,¹⁴N. Kimura,⁵⁶L. Kirsch,⁷S. Klimenko,¹⁹B. Knuteson,³³B. R. Ko,¹⁷S. A. Koay,¹¹

K. Kondo,⁵⁸D. J. Kong,²⁸J. Konigsberg,¹⁹A. Korytov,¹⁹A. V. Kotwal,¹⁷M. Kreps,²⁷J. Kroll,⁴⁶N. Krumnack,⁵ M. Kruse,¹⁷V. Krutelyov,¹¹T. Kubo,⁵⁶T. Kuhr,²⁷N. P. Kulkarni,⁵⁹M. Kurata,⁵⁶Y. Kusakabe,⁵⁸S. Kwang,¹⁴ A. T. Laasanen,⁴⁹S. Lami,^47aS. Lammel,¹⁸M. Lancaster,³¹R. L. Lander,⁸K. Lannon,⁴⁰A. Lath,⁵³G. Latino,^47a,47c I. Lazzizzera,^44a,44bT. LeCompte,²E. Lee,⁵⁴S. W. Lee,^54,pS. Leone,^47aS. Levy,¹⁴J. D. Lewis,¹⁸C. S. Lin,²⁹J. Linacre,⁴³

M. Lindgren,¹⁸E. Lipeles,¹⁰A. Lister,⁸D. O. Litvintsev,¹⁸C. Liu,⁴⁸T. Liu,¹⁸N. S. Lockyer,⁴⁶A. Loginov,⁶¹ M. Loreti,^44a,44bL. Lovas,¹⁵R.-S. Lu,¹D. Lucchesi,^44a,44bJ. Lueck,²⁷C. Luci,^52a,52bP. Lujan,²⁹P. Lukens,¹⁸G. Lungu,⁵¹

L. Lyons,⁴³J. Lys,²⁹R. Lysak,¹⁵E. Lytken,⁴⁹P. Mack,²⁷D. MacQueen,³⁴R. Madrak,¹⁸K. Maeshima,¹⁸K. Makhoul,³³ T. Maki,²⁴P. Maksimovic,²⁶S. Malde,⁴³S. Malik,³¹G. Manca,³⁰A. Manousakis-Katsikakis,³F. Margaroli,⁴⁹C. Marino,²⁷

C. P. Marino,²⁵A. Martin,⁶¹V. Martin,^22,jM. Martı´nez,⁴R. Martı´nez-Balları´n,³²T. Maruyama,⁵⁶P. Mastrandrea,^52a T. Masubuchi,⁵⁶M. E. Mattson,⁵⁹P. Mazzanti,^6aK. S. McFarland,⁵⁰P. McIntyre,⁵⁴R. McNulty,^30,iA. Mehta,³⁰ P. Mehtala,²⁴A. Menzione,^47aP. Merkel,⁴⁹C. Mesropian,⁵¹T. Miao,¹⁸N. Miladinovic,⁷R. Miller,³⁶C. Mills,²³ M. Milnik,²⁷A. Mitra,¹G. Mitselmakher,¹⁹H. Miyake,⁵⁶N. Moggi,^6aC. S. Moon,²⁸R. Moore,¹⁸M. J. Morello,^47a,47b

J. Morlok,²⁷P. Movilla Fernandez,¹⁸J. Mu¨lmensta¨dt,²⁹A. Mukherjee,¹⁸Th. Muller,²⁷R. Mumford,²⁶P. Murat,¹⁸ M. Mussini,^6a,6bJ. Nachtman,¹⁸Y. Nagai,⁵⁶A. Nagano,⁵⁶J. Naganoma,⁵⁸K. Nakamura,⁵⁶I. Nakano,⁴¹A. Napier,⁵⁷

V. Necula,¹⁷C. Neu,⁴⁶M. S. Neubauer,²⁵J. Nielsen,^29,fL. Nodulman,²M. Norman,¹⁰O. Norniella,²⁵E. Nurse,³¹ PHYSICAL REVIEW D79,011104(R) (2009)

L. Oakes,⁴³S. H. Oh,¹⁷Y. D. Oh,²⁸I. Oksuzian,¹⁹T. Okusawa,⁴²R. Oldeman,³⁰R. Orava,²⁴K. Osterberg,²⁴ S. Pagan Griso,^44a,44bC. Pagliarone,^47aE. Palencia,¹⁸V. Papadimitriou,¹⁸A. Papaikonomou,²⁷A. A. Paramonov,¹⁴

B. Parks,⁴⁰S. Pashapour,³⁴J. Patrick,¹⁸G. Pauletta,^55a,55bM. Paulini,¹³C. Paus,³³D. E. Pellett,⁸A. Penzo,^55a T. J. Phillips,¹⁷G. Piacentino,^47aE. Pianori,⁴⁶L. Pinera,¹⁹K. Pitts,²⁵C. Plager,⁹L. Pondrom,⁶⁰O. Poukhov,¹⁶ N. Pounder,⁴³F. Prakoshyn,¹⁶A. Pronko,¹⁸J. Proudfoot,²F. Ptohos,^18,hE. Pueschel,¹³G. Punzi,^47a,47bJ. Pursley,⁶⁰ J. Rademacker,^43,dA. Rahaman,⁴⁸V. Ramakrishnan,⁶⁰N. Ranjan,⁴⁹I. Redondo,³²B. Reisert,¹⁸V. Rekovic,³⁸P. Renton,⁴³

M. Rescigno,^52aS. Richter,²⁷F. Rimondi,^6a,6bL. Ristori,^47aA. Robson,²²T. Rodrigo,¹²T. Rodriguez,⁴⁶E. Rogers,²⁵ S. Rolli,⁵⁷R. Roser,¹⁸M. Rossi,^55aR. Rossin,¹¹P. Roy,³⁴A. Ruiz,¹²J. Russ,¹³V. Rusu,¹⁸H. Saarikko,²⁴A. Safonov,⁵⁴ W. K. Sakumoto,⁵⁰O. Salto´,⁴L. Santi,^55a,55bS. Sarkar,^52a,52bL. Sartori,^47aK. Sato,¹⁸A. Savoy-Navarro,⁴⁵T. Scheidle,²⁷

P. Schlabach,¹⁸A. Schmidt,²⁷E. E. Schmidt,¹⁸M. A. Schmidt,¹⁴M. P. Schmidt,^61,aM. Schmitt,³⁹T. Schwarz,⁸ L. Scodellaro,¹²A. L. Scott,¹¹A. Scribano,^47a,47cF. Scuri,^47aA. Sedov,⁴⁹S. Seidel,³⁸Y. Seiya,⁴²A. Semenov,¹⁶ L. Sexton-Kennedy,¹⁸A. Sfyrla,²¹S. Z. Shalhout,⁵⁹T. Shears,³⁰P. F. Shepard,⁴⁸D. Sherman,²³M. Shimojima,^56,m

S. Shiraishi,¹⁴M. Shochet,¹⁴Y. Shon,⁶⁰I. Shreyber,³⁷A. Sidoti,^47aP. Sinervo,³⁴A. Sisakyan,¹⁶A. J. Slaughter,¹⁸ J. Slaunwhite,⁴⁰K. Sliwa,⁵⁷J. R. Smith,⁸F. D. Snider,¹⁸R. Snihur,³⁴A. Soha,⁸S. Somalwar,⁵³V. Sorin,³⁶J. Spalding,¹⁸

T. Spreitzer,³⁴P. Squillacioti,^47a,47cM. Stanitzki,⁶¹R. St. Denis,²²B. Stelzer,⁹O. Stelzer-Chilton,⁴³D. Stentz,³⁹ J. Strologas,³⁸D. Stuart,¹¹J. S. Suh,²⁸A. Sukhanov,¹⁹I. Suslov,¹⁶T. Suzuki,⁵⁶A. Taffard,^25,eR. Takashima,⁴¹ Y. Takeuchi,⁵⁶R. Tanaka,⁴¹M. Tecchio,³⁵P. K. Teng,¹K. Terashi,⁵¹R. J. Tesarek,¹⁸J. Thom,^18,gA. S. Thompson,²²

G. A. Thompson,²⁵E. Thomson,⁴⁶P. Tipton,⁶¹V. Tiwari,¹³S. Tkaczyk,¹⁸D. Toback,⁵⁴S. Tokar,¹⁵K. Tollefson,³⁶ T. Tomura,⁵⁶D. Tonelli,¹⁸S. Torre,²⁰D. Torretta,¹⁸P. Totaro,^55a,55bS. Tourneur,⁴⁵Y. Tu,⁴⁶N. Turini,^47a,47cF. Ukegawa,⁵⁶

S. Vallecorsa,²¹N. van Remortel,^24,bA. Varganov,³⁵E. Vataga,^47a,47dF. Va´zquez,^19,kG. Velev,¹⁸C. Vellidis,³ V. Veszpremi,⁴⁹M. Vidal,³²R. Vidal,¹⁸I. Vila,¹²R. Vilar,¹²T. Vine,³¹M. Vogel,³⁸I. Volobouev,^29,pG. Volpi,^47a,47b F. Wu¨rthwein,¹⁰P. Wagner,²R. G. Wagner,²R. L. Wagner,¹⁸J. Wagner-Kuhr,²⁷W. Wagner,²⁷T. Wakisaka,⁴²R. Wallny,⁹

S. M. Wang,¹A. Warburton,³⁴D. Waters,³¹M. Weinberger,⁵⁴W. C. Wester III,¹⁸B. Whitehouse,⁵⁷D. Whiteson,^46,e A. B. Wicklund,²E. Wicklund,¹⁸G. Williams,³⁴H. H. Williams,⁴⁶P. Wilson,¹⁸B. L. Winer,⁴⁰P. Wittich,^18,gS. Wolbers,¹⁸ C. Wolfe,¹⁴T. Wright,³⁵X. Wu,²¹S. M. Wynne,³⁰A. Yagil,¹⁰K. Yamamoto,⁴²J. Yamaoka,⁵³U. K. Yang,^14,lY. C. Yang,²⁸ W. M. Yao,²⁹G. P. Yeh,¹⁸J. Yoh,¹⁸K. Yorita,¹⁴T. Yoshida,⁴²G. B. Yu,⁵⁰I. Yu,²⁸S. S. Yu,¹⁸J. C. Yun,¹⁸L. Zanello,^52a,52b

A. Zanetti,^55aI. Zaw,²³X. Zhang,²⁵Y. Zheng,^9,cand S. Zucchelli^6a,6b (CDF Collaboration)

1Institute of Physics, Academia Sinica, Taipei, Taiwan 11529, Republic of China

2Argonne National Laboratory, Argonne, Illinois 60439

3University of Athens, 157 71 Athens, Greece

4Institut de Fisica d’Altes Energies, Universitat Autonoma de Barcelona, E-08193, Bellaterra (Barcelona), Spain

5Baylor University, Waco, Texas 76798

6aIstituto Nazionale di Fisica Nucleare Bologna, I-40127 Bologna, Italy

6bUniversity of Bologna, I-40127 Bologna, Italy

7Brandeis University, Waltham, Massachusetts 02254

8University of California, Davis, Davis, California 95616

9University of California, Los Angeles, Los Angeles, California 90024

10University of California, San Diego, La Jolla, California 92093

11University of California, Santa Barbara, Santa Barbara, California 93106

12Instituto de Fisica de Cantabria, CSIC-University of Cantabria, 39005 Santander, Spain

13Carnegie Mellon University, Pittsburgh, Pennsylvania 15213

14Enrico Fermi Institute, University of Chicago, Chicago, Illinois 60637

15Comenius University, 842 48 Bratislava, Slovakia; Institute of Experimental Physics, 040 01 Kosice, Slovakia

16Joint Institute for Nuclear Research, RU-141980 Dubna, Russia

17Duke University, Durham, North Carolina 27708

18Fermi National Accelerator Laboratory, Batavia, Illinois 60510

19University of Florida, Gainesville, Florida 32611

20Laboratori Nazionali di Frascati, Istituto Nazionale di Fisica Nucleare, I-00044 Frascati, Italy

21University of Geneva, CH-1211 Geneva 4, Switzerland

22Glasgow University, Glasgow G12 8QQ, United Kingdom

23Harvard University, Cambridge, Massachusetts 02138

T. AALTONENet al. PHYSICAL REVIEW D79,011104(R) (2009)

011104-2

24Division of High Energy Physics, Department of Physics, University of Helsinki and Helsinki Institute of Physics, FIN-00014, Helsinki, Finland

25University of Illinois, Urbana, Illinois 61801

26The Johns Hopkins University, Baltimore, Maryland 21218

27Institut fu¨r Experimentelle Kernphysik, Universita¨t Karlsruhe, 76128 Karlsruhe, Germany

28Center for High Energy Physics: Kyungpook National University, Daegu 702-701, Korea;

Seoul National University, Seoul 151-742, Korea;

Sungkyunkwan University, Suwon 440-746, Korea;

Korea Institute of Science and Technology Information, Daejeon, 305-806, Korea;

Chonnam National University, Gwangju, 500-757, Korea

29Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, California 94720

30University of Liverpool, Liverpool L69 7ZE, United Kingdom

31University College London, London WC1E 6BT, United Kingdom

32Centro de Investigaciones Energeticas Medioambientales y Tecnologicas, E-28040 Madrid, Spain

33Massachusetts Institute of Technology, Cambridge, Massachusetts 02139

34Institute of Particle Physics: McGill University, Montre´al, Canada H3A 2T8;

and University of Toronto, Toronto, Canada M5S 1A7

35University of Michigan, Ann Arbor, Michigan 48109

36Michigan State University, East Lansing, Michigan 48824

37Institution for Theoretical and Experimental Physics, ITEP, Moscow 117259, Russia

38University of New Mexico, Albuquerque, New Mexico 87131

39Northwestern University, Evanston, Illinois 60208

40The Ohio State University, Columbus, Ohio 43210

41Okayama University, Okayama 700-8530, Japan

42Osaka City University, Osaka 588, Japan

43University of Oxford, Oxford OX1 3RH, United Kingdom

44aIstituto Nazionale di Fisica Nucleare, Sezione di Padova-Trento, I-35131 Padova, Italy

44bUniversity of Padova, I-35131 Padova, Italy

45LPNHE, Universite Pierre et Marie Curie/IN2P3-CNRS, UMR7585, Paris, F-75252 France

46University of Pennsylvania, Philadelphia, Pennsylvania 19104

47aIstituto Nazionale di Fisica Nucleare Pisa, I-56127 Pisa, Italy;

47bUniversity of Pisa, I-56127 Pisa, Italy

47cUniversity of Siena, I-56127 Pisa, Italy

47dScuola Normale Superiore, I-56127 Pisa, Italy

48University of Pittsburgh, Pittsburgh, Pennsylvania 15260

49Purdue University, West Lafayette, Indiana 47907

50University of Rochester, Rochester, New York 14627

51The Rockefeller University, New York, New York 10021

52aIstituto Nazionale di Fisica Nucleare, Sezione di Roma 1, I-00185 Roma, Italy

52bSapienza Universita` di Roma, I-00185 Roma, Italy

rVisitors from Royal Society of Edinburgh/Scottish Executive Support Research Fellow.

qVisitors from IFIC (CSIC-Universitat de Valencia), 46071 Valencia, Spain.

pVisitors from Texas Tech University, Lubbock, TX 79409, USA.

oVisitors from Queen Mary, University of London, London, E1 4NS, England.

nVisitors from University de Oviedo, E-33007 Oviedo, Spain.

mVisitors from Nagasaki Institute of Applied Science, Nagasaki, Japan.

lVisitors from University of Manchester, Manchester M13 9PL, England.

kVisitors from Universidad Iberoamericana, Mexico D.F., Mexico.

jVisitors from University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom.

iVisitors from University College Dublin, Dublin 4, Ireland.

hVisitors from University of Cyprus, Nicosia CY-1678, Cyprus.

gVisitors from Cornell University, Ithaca, NY 14853, USA.

fVisitors from University of California Santa Cruz, Santa Cruz, CA 95064, USA.

eVisitors from University of California Irvine, Irvine, CA 92697, USA.

dVisitors from University of Bristol, Bristol BS8 1TL, United Kingdom.

cVisitors from Chinese Academy of Sciences, Beijing 100864, China.

bVisitors from Universiteit Antwerpen, B-2610 Antwerp, Belgium.

aDeceased.

SEARCH FOR THE RARE DECAYS. . . PHYSICAL REVIEW D79,011104(R) (2009)

53Rutgers University, Piscataway, New Jersey 08855

54Texas A&M University, College Station, Texas 77843

55aIstituto Nazionale di Fisica Nucleare Trieste/Udine, Udine, Italy

55bUniversity of Trieste/Udine, Udine, Italy

56University of Tsukuba, Tsukuba, Ibaraki 305, Japan

57Tufts University, Medford, Massachusetts 02155

58Waseda University, Tokyo 169, Japan

59Wayne State University, Detroit, Michigan 48201

60University of Wisconsin, Madison, Wisconsin 53706

61Yale University, New Haven, Connecticut 06520 (Received 25 April 2008; published 22 January 2009)

We search for b!s^þ transitions in B meson (B^þ, B⁰, or B⁰s) decays with 924 pb¹ of pp collisions at ffiffiffi

ps

¼1:96 TeV collected with the CDF II detector at the Fermilab Tevatron. We find excesses with significances of 4.5, 2.9, and 2.4 standard deviations in the B^þ!^þK^þ, B⁰! ^þKð892Þ⁰, andB⁰s !^þdecay modes, respectively. UsingB!J=ch(h¼K^þ,Kð892Þ⁰, ) decays as normalization channels, we report branching fractions for the previously observedB^þ and B⁰ decays, BðB^þ!^þK^þÞ ¼ ð0:590:150:04Þ 10⁶, and BðB⁰!^þKð892Þ⁰Þ ¼ ð0:810:300:10Þ 10⁶, where the first uncertainty is statistical, and the second is systematic. We set an upper limit on the relative branching fractionBðB⁰_s !^þÞ=BðB⁰_s !J=cÞ<2:6ð2:3Þ 10³at the 95(90)% confidence level, which is the most stringent to date.

DOI:10.1103/PhysRevD.79.011104 PACS numbers: 13.20.He, 12.15.Mm, 14.40.Nd

The decay of abquark into ansquark and two muons (b!s^þ) is a flavor-changing neutral current process, forbidden at tree level in the standard model (SM) but allowed through highly suppressed internal loops. New physics could manifest itself in a larger branching fraction, a modified dimuon mass distribution, or angular distribu- tions of the decay products different from that predicted by the SM [1–4]. In this paper, we report branching ratio measurements of exclusive decays, where the s quark hadronizes into a single meson. Reconstructing a final state with only three or four charged final state particles results in smaller backgrounds than those expected in a search for inclusive B!Xs^þ decays. The rare decays B^þ ! ^þK^þandB⁰ !^þKð892Þ⁰have been observed at the B factories [5,6], with branching fractions of Oð10⁶Þ, consistent with SM predictions [7–14]. The analogous decay in the B⁰s system,B⁰s !^þ, has a predicted branching ratio of 1:610⁶ [15], but has not yet been observed [16,17]. We report branching ratio mea- surements from924 pb¹of Collider Detector at Fermilab (CDF) Run II data that pave the way for future studies of larger data sets from which kinematic distributions may be measured. We search for B!^þh decays, where B stands forB^þ,B⁰, orB⁰_s, andhstands forK^þ,Kð892Þ⁰, or , respectively. TheKð892Þ⁰, referred to asK⁰ through- out this paper, is reconstructed in theK⁰!K^þ, decay mode, and themeson is reconstructed as !K^þK. We measure branching ratios relative to B!J=ch de- cays, followed byJ=c !^þdecays, resulting in the same final state particles as the rare decay modes. Many systematic uncertainties cancel in the relative branching ratios:

BðB!^þhÞ

BðB!J=chÞ ¼N^þh

NJ=ch

J=ch

^þh

BðJ=c!^þÞ;

(1) where N^þh is the observed number of B!^þh decays, N_J=ch is the observed number of B!J=chde- cays, whileJ=chand^þh are the combined selection efficiency and acceptance of the experiment for B! J=chandB!^þhrespectively. Throughout this re- port, charge conjugate modes are implicitly included.

CDF II is a general purpose detector, located at the Tevatron pp collider [18]. Charged particle trajectories (tracks) are detected by the tracking system comprised of a seven-layer double-sided silicon microstrip detector and a drift chamber, both in a 1.4 T axial magnetic field. The silicon detector [19] ranges in radius from 1.3 to 28 cm, and has a single-hit resolution of approximately 15m.

The drift chamber [20] provides up to 96 measurements from radii of 40 to 137 cm with a single-hit resolution of approximately 180m. A muon chamber identification system of plastic scintillators and drift chambers [21] is located on the exterior of the detector with a central part coveringjj<0:6, and an extended region covering0:6<

jj<1:0, where is the pseudorapidity [22]. In the central (extended) region, muons are detected if their transverse momentum component pT is greater than 1:5ð2:0ÞGeV=c. Events are selected with a three-level trigger system. The first trigger level requires the presence of two charged particles withpT 1:5 GeV=c(jj 0:6) or pT 2:0 GeV=c (0:6 jj 1:0), matched to track segments in the muon chambers to form muon candidates.

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At the second level, a more restrictive selection is made by requiring that the muon candidates have opposite charge, and that their opening angle in the plane transverse to the beam line is less than 120. At the third trigger level, the event is fully reconstructed. The trajectories of the muon candidates in the silicon detector are required to intersect at a point which is displaced transversely from the beam line by at least100m.

The off-line selection begins with a suppression of ran- dom combinations of tracks satisfying the selection re- quirements (combinatoric background), by requiring that all tracks have pT>0:4 GeV=c and match hits from at least three layers of the silicon detector. The trajectories of a pair of muon candidates that satisfy the trigger require- ments, and the tracks that form the hadron candidate, are fitted with the constraint that they originate from a single vertex in three-dimensional space to form aB candidate.

The² probability of the fit is required to be greater than 10³. AK^þcandidate is a track assigned the charged kaon mass, and theK⁰ () candidates are formed from oppo- sitely charged pairs of tracks whose invariant mass must lie within50ð10Þ MeV=c² of theK⁰ () mass. For all parti- cles, we use the world average values tabulated in Ref. [23]. The ambiguity of the mass assignment inB⁰ ! ^þK⁰decays is handled by choosing the combination whose K^þ mass is closer to the K⁰ mass. In recon- structing theBcandidates, the meson containing a strange quarkhis required to havepTðhÞ 1:0 GeV=c, and theB candidate is required to have pTðBÞ 4:0 GeV=c. We require that the distance of closest approach between the flight path of theBcandidate and the beam line,jd0ðBÞj, is less than120m, to reduce the combinatoric background with no loss of signal.

Normalization mode candidates are identified by having a dimuon invariant mass within 50 MeV=c² of the J=c mass, yielding approximately 12 000B^þ!J=cK^þ, 4400B⁰!J=cK⁰, and 800B⁰s!J=c decays. The B candidate mass distributions of all modes are compatible with a Gaussian of width ¼20 MeV=c². To reduce backgrounds fromBdecays to mesons containingcquarks, several vetoes are applied to B!^þh candidates, listed below. We eliminate candidates with a dimuon mass near theJ=c^ð0Þ:2:9m 3:2 GeV=c² or3:6 m3:75 GeV=c² respectively. B!J=c^ð0Þh decays followed by the radiative decay of the J=c^{ð0Þ into two} muons and a photon that is not reconstructed may have a dimuon mass that passes theJ=c^ð0Þveto. We reject these events making use of the correlation between the candi- date’s invariant mass and the dimuon invariant mass, and require jðm_hm_BÞ ðmm_J=cð⁰_ÞÞj>

100 MeV=c².B!J=c^ð0Þhdecays with one hadron mis- identified as a muon form a potential background to the rare decay search. We reject this class of background by requiring that all combinations of tracks of the candidate have an invariant mass that differs by at least40 MeV=c²

from theJ=c^ð0Þmass. We also reject candidates with track pairs with a mass within25 MeV=c²of theD⁰ !K^þ decay, or track triplets compatible with a mass within 25 MeV=c² of the D^þ!K^þþ or D^þ_s ! K^þK^þdecays.

We further improve the signal to background ratio by an optimization of the selection based on discriminating var- iables. For this purpose, Monte Carlo (MC) simulations of the signal processes are used. We generate singlebhadrons using the transverse momentum spectrum from B! J=cX, measured by CDF [18]. Decays of all bhadrons are simulated using EVTGEN [24], with lifetimes from Ref. [23], allowing for a decay width difference between the B⁰_s mass eigenstates, =¼0:120:06 [25]. The decaysB⁰ !J=cK⁰ andB⁰s !J=care simulated ac- cording to the polarization amplitudes measured by CDF [26]. The dynamics of the rare decay processes are simu- lated according to the calculations of Ali et al. [11]. For B⁰s!^þ, we assume a mixture of 50%CP-even and 50%CP-odd states. The interactions of final state particles are simulated using a GEANT [27] model of the CDF II detector, digitized into the CDF event format, and recon- structed using the same software as in the processing of collision data. The detector simulation includes a full emulation of the CDF trigger system. We find that the transverse momentum spectrum of the B mesons of this measurement are on average higher than in the simulation.

This can be explained by the presence of a B baryon component with low transverse momentum in the mea- surement used as input spectrum of the simulation [18]. To correct for this, the simulated events are weighted by a polynomial function, which is obtained from the ratio of data to MC transverse momentum distribution of the B meson.

We tighten the candidate selection to obtain the smallest expected statistical uncertainty on the measurement of the B!^þh branching ratios by finding the selection with the largest value ofNsig= ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi

NsigþNbkg

p . The expected

number of signal eventsNsig is determined by scaling the MC yields of the rare decay modes to the yields of the normalization channels in the data, and correcting by the relative branching ratios and selection efficiencies. This procedure requires estimates of the branching ratios of the rare decay modes. For the B^þ !^þK^þ and B⁰! ^þK⁰ decays we use the world average measured branching ratios [23], while for B⁰s !^þ we use the theoretical estimate [15]. The expected number of background events Nbkg is estimated by extrapolating the candidate yield with an invariant massð180–300ÞMeV=c² higher than the B mass, to the signal region. Candidates with an invariant mass lower than the B mass are not suitable for background estimates, since they contain par- tially reconstructed B decays, not expected in the signal region. We find good discriminating power between signal and background from the following three quantities:t=t,

SEARCH FOR THE RARE DECAYS. . . PHYSICAL REVIEW D79,011104(R) (2009)

, andI. The significance of the proper decay timet=tis defined as the proper decay time of the B candidate, divided by its uncertainty. The angle is defined as the difference in angle between theBcandidate’s momentum vector and the vector from the primary vertex to theh vertex. The isolationIis defined as the transverse momen- tum carried by the B meson candidate divided by the transverse momentum of all tracks in a cone offfiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi R¼

²þ²

p ¼1:0around the direction of theB meson candidate, including those of theB candidate itself. Here is the difference in pseudorapidity of theBcandidate and each track, andis the difference in their azimuthal angles. Scanning different combinations of selection thresholds, we find that the optimal values are very similar for the three rare decay modes:t=t14,60 mrad, and I0:6. Applying the optimized selection require- ments to the normalization channels yields the distribu- tions shown in Fig. 1. The shape of the combinatoric background is estimated from a sample with poor vertex quality (²probability<10³). The invariant mass distri-

bution of this poor vertex quality sample is fitted with a Gaussian distribution for the remaining signal contribution and an exponential plus a constant to model the back- ground. We estimate the background in the signal region of the tight selection using this functional form, normalized to the number of candidates with invariant mass ð60–180ÞMeV=c² higher than the B mass. Using this method, we find 636182B^þ!J=cK^þ, 2423 52B⁰ !J=cK⁰, and43122B⁰_s !J=c decays. The invariant mass distributions for the rare decay modes are shown in Fig.2. In the40 MeV=c²window around theB mass we find 90B^þ!^þK^þ, 35B⁰ !^þK⁰, and11B⁰s!^þcandidates. From simulation studies we verified that the present selection accepts decays for every kinematically possible dimuon invariant mass, with an efficiency difference not exceeding a factor two, except for the windows around theJ=c^ð0Þthat have been explicitly excluded.

For the signal modes, we evaluate three sources of background: the combinatoric background, hadrons mis- identified as muons, and hadrons with misassigned mass.

2) ) (GeV/c K+

µ µ m(

5 5.1 5.2 5.3 5.4 5.5 5.6 5.7

2Candidates per 10 MeV/c

0 5 10 15

20 B⁺→µµ K⁺ Data

Signal region Sideband region

a

2) ) (GeV/c K*0

µ µ m(

5 5.1 5.2 5.3 5.4 5.5 5.6 5.7

2Candidates per 10 MeV/c

0 2 4 6

8 ^Data

K*0

µ µ

0→ B

Signal region Sideband region

b

2) ) (GeV/c φ µ µ m(

5 5.1 5.2 5.3 5.4 5.5 5.6 5.7

2Candidates per 10 MeV/c

0 1 2 3 4

5 _{→µµφ Data}

Bs

Signal region Sideband region

c

FIG. 2 (color online). Invariant mass spectra of (a)^þK^þ, (b)^þK⁰, and (c)^þcandidates. The superimposed curves are not a fit, but a sum of a single Gaussian with a width of 20 MeV=c² representing the signal, and a curve representing the background as determined by the procedure described in the text. The curves are not drawn for masses below the signal window since they are not expected to predict the background level where partially reconstructedBdecays contribute.

2) K) (GeV/c ψ m(J/

5 5.1 5.2 5.3 5.4 5.5 5.6 5.7

2Candidates per 5 MeV/c

0 100 200 300 400 500 600 700

Data Signal region Sideband region

a

2) K*) (GeV/c ψ m(J/

5 5.1 5.2 5.3 5.4 5.5 5.6 5.7

2Candidates per 5 MeV/c

0 50 100 150 200

250 ^Data

Signal region Sideband region

b

2) ) (GeV/c φ ψ m(J/

5 5.1 5.2 5.3 5.4 5.5 5.6 5.7

2 Candidates per 5 MeV/c

0 10 20 30 40 50 60

Data Signal region Sideband region

c

FIG. 1 (color online). Invariant mass spectra of (a) J=cK^þ, (b) J=cK⁰, and (c) J=c candidates after applying optimized selection requirements.

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As in the normalization mode, the shape of the combina- toric background is estimated from a sample with poor vertex quality (²probability<10³). The invariant mass distribution of these candidates is fitted to an exponential plus a constant, shown in Fig.3. This functional form is used to extrapolate the number of candidates with invariant mass ð60–180Þ MeV=c² higher than the B mass to the signal region. The resulting backgrounds, and their statis- tical uncertainties, consist of44:35:8, 16:33:6, and 3:11:5 candidates for the B^þ!^þK^þ, B⁰ ! ^þK⁰, andB⁰s !^þdecay modes, respectively.

The statistical error on the fitted parameters from the background sample is included in the quoted error.

Backgrounds from hadrons misidentified as muons are estimated from simulation. Final state particles from simu- lated charmless B decays are weighted with the muon misidentification probabilities. The misidentification prob- abilities for charged kaons and pions are measured from a sample of D^þ!D^0þ followed by D⁰!K^þ de- cays. We estimate a net background of 1.0 events for the B^þ!^þK^þ channel, primarily coming from misi- dentified B^þ!K^þþ decays. For the B⁰ and B⁰s

modes, this background is negligible. From simulation we determine the background contribution that arises from assigning the wrong masses to the hadrons. We estimate 0:4B⁰!^þK⁰ decays which are recon- structed as B⁰s !^þand 0:2B⁰s !^þ decays reconstructed asB⁰ !^þK⁰. Nonresonant contribu- tions in the K⁰ region have been measured in radiative decays to be1%[28], and we neglect them as a potential background.

We calculate the signal yield by subtracting the pre- dicted background from the number of candidates in the signal window. We find an excess in theBsignal region in all three channels, and determine the significance by cal- culating the Poisson probability for the background to fluctuate to the number of observed events or higher, taking into account the statistical and systematic uncertainty on

the background. We find an equivalent Gaussian signifi- cance of 4.5, 2.9, and 2.4 standard deviations, respectively, for theB^þ,B⁰, andB⁰s modes.

TableIlists the systematic uncertainties associated with the relative selection efficiency, discussed in further detail below. To take into account the uncertainty on the relative efficiency due to uncertainties in the dynamics of the rare decays, we apply the weak form factors from Ref. [29,30]

and evaluate the largest difference between the reconstruc- tion efficiency and the central value. We find an uncertainty of 3.1% or less. The uncertainty related to the p_TðBÞ spectrum is evaluated from the change in relative effi- ciency when the three parameters in thepTðBÞweighting function are varied by 1 standard deviation of their values determined from fits to data, taking into account correla- tions. The difference reaches 1.4% in the B⁰s mode. The muon trigger efficiency close to the1:5 GeV=c p_Tthresh- old is poorly known. We find a change in the relative efficiency reaching 1.3% if the minimumpT is varied by 100 MeV=c, covering the range over which the trigger efficiency rises from zero to one. The final state particles of the rare decay modes have approximately 10% more low momentum tracks than those of the normalization chan- TABLE I. Systematic uncertainties on the relative efficiency quoted in percent.

Channel B^þ B⁰ Bs

Theory model 1.5 3.1 1.6

pTðBÞspectrum 0.6 1.3 1.4

Trigger turn-on 1.3 1.3 1.2

Low momentum hadrons 0.2 0.2 0.2

B⁰s decay width difference 8.7

Polarization 0.6 0.1

Normalization channel statistics 1.3 2.1 5.1 B^þ!J=c^þcontribution 0.1

MC statistics 1.6 2.6 2.2

Total 2.9 5.0 10.6

2) ) (GeV/c K+

µ µ m(

5 5.1 5.2 5.3 5.4 5.5 5.6 5.7

2Candidates per 10 MeV/c

0 10 20 30 40

a

2) ) (GeV/c K*0

µ µ m(

5 5.1 5.2 5.3 5.4 5.5 5.6 5.7

2Candidates per 10 MeV/c

0 5 10 15 20 25 30

35 b

2) ) (GeV/c φ µ µ m(

5 5.1 5.2 5.3 5.4 5.5 5.6 5.7

2Candidates per 10 MeV/c

0 2 4 6 8 10

12 c

FIG. 3. Invariant mass spectra of samples used for determining the background shapes for (a) ^þK^þ, (b) ^þK⁰, and (c)^þcandidates. The selections differ from those used for Fig.2, in that the selection on the vertex quality requirement has been inverted:² probability<10³. Superimposed is a curve that represents the fit to an exponential plus a constant.

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nels. The simulation models the track reconstruction effi- ciency to an accuracy of 2% in the p_T range of 0:4–1:5 GeV=c. We therefore assign a systematic uncer- tainty on the relative efficiency of2%10%¼0:2%. We find an uncertainty of 8.3% on the relative efficiency ofB⁰s

decays due to the unknown fraction of the short-lived CP-even state in the rare decay mode. We assume that the CP-even fraction is 0.5, and assess systematic uncer- tainties for the extremes of the fraction valued at 1.0 and 0.0. In addition, the uncertainty on=contributes an- other 2.6%, resulting in a total uncertainty of 8.7% asso- ciated with the B⁰s decay width difference. This is the largest systematic uncertainty on the relative efficiency of theB⁰_s mode. We evaluate the effect of the uncertainty on the fraction ofJ=c mesons produced with a longitudi- nal polarization by varying the fraction measured at CDF [26] by 1. The effect is 0.6% forB⁰!J=cK⁰ and 0.1% forB⁰_s !J=c.

The statistical uncertainties of yields in the normaliza- tion channels are included as systematic uncertainties, which range from 1.3% for the B^þ channel to 5.1% for the B⁰s channel. Cabibbo-suppressed B^þ!J=c^þ de- cays contribute 0.1% to the yield of the normalization channel for theB^þ channel. We introduce the full effect into our estimate of the systematic uncertainty without correcting the result. The relative efficiencies between signal and normalization channels, of0:710:01,0:74 0:02, and 0:840:02 for the B^þ, B⁰, and B⁰_s decays, respectively, have uncertainties reaching 2.6%, that arise from the finite size of the MC samples.

The predicted background values depend on the shape of the background function. We evaluate the change in the background yield calculation when using a sample that is similar to the one resulting from the optimal selection, but has less stringent requirements on the three optimization variables instead of the default sample with poor vertex quality. We compare two functional models for the back- ground description, the default exponential plus a constant, and a simpler linear extrapolation function. We find a systematic uncertainty on the background prediction reaching 10% for theB⁰_s channel.

To calculate the systematic uncertainty on the relative branching fraction, the relative efficiency uncertainty is summed in quadrature with the uncertainty of theJ=c ! ^þ branching ratio, and with the systematic uncer- tainty on the number of signal candidates.

To calculate the absolute branching fractions, we use the world average branching fractions of the normalization channels [23]. These branching fractions have uncertain- ties of 3.5%, 4.5%, and 35.5%, respectively, forB^þ,B⁰, and B⁰s, which are added in quadrature to the systematic un- certainties on the relative branching ratios. A summary of the systematic uncertainties is given in TableII.

We calculate relative branching ratios using Eq. (1), and find BðB^þ!^þK^þÞ=BðB^þ!J=cK^þÞ ¼ ð0:590:150:03Þ 10³, BðB⁰!^þK⁰Þ=

BðB⁰!J=cK⁰Þ ¼ ð0:610:230:07Þ 10³, and BðB⁰_s!^þÞ=BðB⁰_s!J=cÞ¼ð1:230:600:14Þ 10³, where the first uncertainty is statistical and the second is systematic. We use the world average branching ratios of the B⁰ and B^þ normalization channels [23], resulting in the following absolute branching fractions:

BðB^þ!^þK^þÞ ¼ ð0:590:150:04Þ 10⁶ and BðB⁰!^þK⁰Þ ¼ ð0:810:300:10Þ 10⁶. To obtain an absolute branching ratio for the B⁰_s !^þ decay, we use BðB⁰_s!J=cÞ ¼ ð1:380:49Þ 10³, obtained from correcting the CDF measurement [31] for the current value of f_s=f_d [23], theB⁰_s to B⁰ production ratio, resulting in BðB⁰_s!^þÞ ¼ ð1:700:82 0:64Þ 10⁶. We find a significance of only 2.4 standard TABLE II. Summary of systematic uncertainties quoted in

percent.

Channel B^þ B⁰ Bs

Total relative efficiency uncertainty 2.9 5.0 10.6 BðJ=c !^þÞ 1.0 1.0 1.0

Background prediction 5.2 3.1 10.2

BðB!J=chÞ 3.5 4.5 35.5

TABLE III. Summary of the main ingredients and results of this analysis. Where one uncertainty is quoted, the uncertainty is of statistical nature. Where two uncertainties are quoted, the first is statistical and the second is systematic.

Decay mode B^þ!^þK^þ B⁰!^þK⁰ B⁰s !^þ

Nobs 90 35 11

Nbkg 45:35:8 16:53:6 3:51:5 Nsig 44:75:8 18:53:6 7:51:5

Gaussian significance 4:5 2:9 2:4

NJ=ch 636182 242352 43122

^þh=J=ch 0:710:01 0:740:02 0:840:02 RelativeB10³ 0:590:150:03 0:610:230:07 1:230:600:14 AbsoluteB10⁶ 0:590:150:04 0:810:300:10 1:700:820:64

RelativeB95(90)% CL limit10³ 2.6(2.3)

AbsoluteB95(90)% CL limit10⁶ 6.0(5.0)

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