BTeV
• The final aim of BTeV experiment is to search for
New Physics in the Heavy Flavor sector, b and c
• We could either discover it or contribute to
individuate the New Model generating it, if
discovered elsewhere (LHC)
– Each New Model impacts the HF measurements with
different patterns
– and these could be the only way to distinguish among them
• To succeed in this, BTeV exploits the huge potential
of the Tevatron collider in terms of produced b
–  41011 b-hadrons per 107s at L = 21032 cm-2s-1
– All the b-hadron species are produced: B, Bs, Bc, b, …
BTeV forever
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BTeV Collaboration
Belarussian State- D .Drobychev, Univ. of Illinois- M. Haney, D.
A. Lobko, A. Lopatrik, R. Zouversky
UC Davis - P. Yager
Kim, M. Selen, V. Simatis, J. Wiss
Univ. of Colorado at Boulder
P. Ratcliffe, M. Rovere
J. Cumalat, P. Rankin, K. Stenson
INFN - Frascati- M. Bertani, L.
Univ. of Insubria in Como-
Benussi, S. Bianco, M. Caponero, D.
Collona, F. Fabri, F. Di Falco, F.
J. Appel, E. Barsotti, C. Brown,
Felli, M. Giardoni, A. La Monaca,
E. Pace, M. Pallota, A. Paolozzi , S.
J. Butler, H. Cheung, D. Christian,
Tomassini
S. Cihangir, M. Fischler,
INFN - Milano – G. Alimonti,
I. Gaines, P. Garbincius, L. Garren,
P’Dangelo, M. Dinardo, L. Edera, S.
E. Gottschalk, A. Hahn, G. Jackson,
Erba, D. Lunesu, S. Magni, D.
P. Kasper, P. Kasper, R. Kutschke,
Menasce, L. Moroni, D. Pedrini, S.
S. W. Kwan, P. Lebrun, P. McBride,
Sala , L. Uplegger
J. Slaughter, M. Votava, M. Wang,
INFN - Pavia - G. Boca, G.
J. Yarba
Cossali, G. Liguori, F. Manfredi, M.
Univ. of Florida at Gainesville Maghisoni, L. Ratti, V. Re, M.
Santini, V. Speviali, P. Torre, G.
P. Avery
Traversi
University of Houston –
IHEP Protvino, Russia - A.
A. Daniel, K. Lau, M. Ispiryan,
Derevschikov, Y. Goncharenko, V.
B. W. Mayes, V. Rodriguez,
Khodyrev, V. Kravtsov, A.
Meschanin, V. Mochalov,
S. Subramania, G. Xu
Morozov, L. Nogach, P.
Illinois Institute of Technology D.
Semenov K. Shestermanov,
R. Burnstein, D. Kaplan,
L. Soloviev, A. Uzunian, A. Vasiliev
L. Lederman, H. Rubin, C. White
University of Iowa
Fermi National Lab
C. Newsom, & R. Braunger
University of Minnesota Syracuse UniversityJ. Hietala, Y. Kubota, B. Lang,
R. Poling, A. Smith
Nanjing Univ. (China)- T.
Y. Chen, D. Gao, S. Du, M.
Qi, B. P. Zhang, Z. Xi Xang,
J. W. Zhao
New Mexico State V.
Papavassiliou
Northwestern Univ. -
M. Artuso, C. Boulahouache,
S. Blusk, J. Butt, O.
Dorjkhaidav, J. Haynes, N.
Menaa, R. Mountain,
H. Muramatsu, R. Nandakumar,
L. Redjimi, R. Sia,
T. Skwarnicki, S. Stone, J. C.
Wang, K. Zhang
J. Rosen
Univ. of Tennessee
Ohio State University-
T. Handler, R. Mitchell
K. Honscheid, & H. Kagan
Vanderbilt University
Univ. of Pennsylvania
W. Johns, P. Sheldon,
W. Selove
Univ. E. Vaandering, & M. Webster
of Puerto Rico
A.
University of Virginia M.
Lopez, H. Mendez, J.
Arenton, S. Conetti, B. Cox, A.
Ledovskoy, H. Powell, M.
Univ. of Science & Tech. Ronquest, D. Smith, B.
of China - G. Datao, L. Hao, Stephens, Z. Zhe
Ge Jin, L. Tiankuan, T. Yang, &
X. Q. Yu
Shandong Wayne State University G.
Univ. (China)- C. F. Feng, Bonvicini, D. Cinabro,
Yu Fu, Mao He, J. Y. Li, L. A. Schreiner
Xue, N. Zhang, & X. Y. Zhang
Ramierez, W. Xiong
Southern Methodist –
T. Coan, M. Hosack
University of Wisconsin
M. Sheaff
York University - S. Menary
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b-physics in the forward region
 = -ln(tan 2q )
• BTeV covers the p-bar forward region , where the b production peaks
– 1.9<<4.5
• The higher b momenta limit MCS effects & boost the b/b values
• The strong b b-bar angular correlation makes the flavor tagging much easier
BTeV forever
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p
beam line
Pixel detector inside
magnet, allows for first
level triggering, on
detached vertices, since
low pt tracks with large
multiple scattering can
be eliminated
BTeV forever
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Pixel Vertex Detector
•
•
•
•
•
•
Low occupancy
Excellent signal/noise
Fast readout
Excellent resolution (5-10 mm
in 1999 FNAL test beam run)
radiation hard sensors and
readout chips (demonstrated in
exposures at IUCF)
Allows for Vertex Trigger at the
lowest level
4.25 cm
BTeV forever
30 stations, 130cm
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BTeV L1 Vertex Trigger
•
•
Performs a real-time full reconstruction of tracks and
vertices of each collision to look for secondary vertices
Trigger decision
–
•
based on the number of tracks having
an impact parameter significance
b/b > n
b,b/b
For a requirement of at least 2 tracks detached by more than
4, we trigger on only 1% of the beam crossings and
achieve the following efficiencies for these states at Level 1:
State
B  p+pBs  DsK
B-  DoKB-  Ksp-
efficiency(%)
55
70
60
40
state
efficiency(%)
Bo  K+p54
Bo  J/y Ks
50
Bs  J/yK*
69
Bo  K*g
40
BTeV forever
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Forward Tracker
• Very solid and redundant system with Straws at large angles
and Micro-strip in the inner region around the beam pipe
– 7 stations with 3 views, X, U and V
– Achieves a momentum resolution < 1%
• Here is where the Italian construction effort is concentrated
BTeV forever
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RICH: Two systems
• Gas + Mirror + MAPMT
to identify b decay
products
• Liquid + PMT’s to help
with flavor tagging of b’s
(p/K separation for p < 9
GeV/c)
• Excellent particle id.
distinguishes BTeV from
“Central pp Detectors”
BTeV forever
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PbWO4 EM Calorimeter
• Use CMS development of crystal technology. Now
used for CMS, ALICE, JLAB, etc…
• Use Photomultiplier tubes instead of APD’s
•Excellent performance in energy
resolution
•Together with the pixel vertex trigger,
one of the unique feature of BTeV
•Allows BTeV to make precision
measurement of modes involving
g and p0
BTeV forever
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Some of BTeV’s Physics Reach in 2 fb-1(CKM)
Reaction
Bop+pBs Ds KBoJ/y KS
J/y l+ l -
Bs Ds p-
B (B)(x10-6)
# of Events
S/B
Parameter
Error or (Value)
4.5
14,600
3
Asymmetry
0.030
300
7500
7
g
8o
445
168,000
10
sin(2b)
0.017
3000
59,000
3
xs
(75)
170
1
g
13o
B-Do (K+p-) K-
0.17
B-Do (K+K-) K-
1.1
1,000
>10
B-KS p-
12.1
4,600
1
Bo K+p-
18.8
62,100
20
Bor+p-
28
5,400
4.1
Boropo
5
780
0.3
BsJ/y ,
330
2,800
15
BsJ/y 
670
9,800
30
<4o +
g
theory errors
a
~4o
sin(2c)
0.024
Just
because
a mode
isn’t
listed,
doesn’t
mean
we can’t
do it!
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