studies of d semileptonic decays at cleo-c
DESCRIPTION
Studies of D Semileptonic Decays at CLEO-c. Bo Xin. Ph.D. Thesis Defense West Lafayette, Indiana, April 14, 2009. Introducing Myself. A one word definition A HEP graduate Student from China, working on D semileptonic decays at the CLEO-c experiment. Introducing Myself. - PowerPoint PPT PresentationTRANSCRIPT
Studies of D Semileptonic Decay at CLEO-c Bo XinPh.D. Thesis Defense 1
Studies of Studies of DD Semileptonic Decays at CLEO-c Semileptonic Decays at CLEO-c
Bo Xin
Ph.D. Thesis DefenseWest Lafayette, Indiana, April 14, 2009
Introducing MyselfIntroducing Myself• A one word definition
– A HEP graduate Student from China, working on
D semileptonic decays at the CLEO-c experiment
Studies of D Semileptonic Decay at CLEO-c Bo Xin 2Ph.D. Thesis Defense
Introducing MyselfIntroducing Myself• A one word definition
– A HEP graduate Student from China, working on
D semileptonic decays at the CLEO-c experiment
Studies of D Semileptonic Decay at CLEO-c Bo Xin 3Ph.D. Thesis Defense
• Before I came to Purdue– A Graduate Student working on
Ψ(2S) decays at the BEijing Spectrometer (BES) experiment
0(2S) , Phys.Rev.D71,072006 2005 ;
(2S) Phys.Rev.D69,092001 2004 ;
HEP & NP (in Chinese) 28(6), 621(2004).cJ
pp pp
pp
Particle Identification
Introducing MyselfIntroducing Myself• A one word definition
– A HEP graduate Student from China, working on
D semileptonic decays at the CLEO-c experiment
Studies of D Semileptonic Decay at CLEO-c Bo Xin 4Ph.D. Thesis Defense
• Before I came to Purdue– A Graduate Student working on
Ψ(2S) decays at the BEijing Spectrometer (BES) experiment
0(2S) , Phys.Rev.D71,072006 2005 ;
(2S) Phys.Rev.D69,092001 2004 ;
HEP & NP (in Chinese) 28(6), 621(2004).cJ
pp pp
pp
Particle Identification
• A summary of my years at Purdue– 5 years in graduate school– 4 physics analyses– 3 years of service work
Introducing MyselfIntroducing Myself• A one word definition
– A HEP graduate Student from China, working on
D semileptonic decays at the CLEO-c experiment
Studies of D Semileptonic Decay at CLEO-c Bo Xin 5Ph.D. Thesis Defense
• Before I came to Purdue– A Graduate Student working on
Ψ(2S) decays at the BEijing Spectrometer (BES) experiment
0(2S) , Phys.Rev.D71,072006 2005 ;
(2S) Phys.Rev.D69,092001 2004 ;
HEP & NP (in Chinese) 28(6), 621(2004).cJ
pp pp
pp
Particle Identification
• A summary of my years at Purdue– 5 years in graduate school– 4 physics analyses– 3 years of service work– 2 great universities (Purdue & Cornell)– 1 great adviser
Thank you!
Physics AnalysesPhysics Analyses
Studies of D Semileptonic Decay at CLEO-c Bo Xin 6Ph.D. Thesis Defense
0 0
1
/ / /
BF & FF (281 pb )
eD K K e
1
Observation of
(281 pb )eD e
1
Observation of
' &
FF (818 pb )
e
e
D e
D e
2005 2006 2007 2008 2009
Jul 05 - Feb 07
Oct 06 - Jan 09
0 0
1( )
/ / /
BF & FF & |V | (818 pb )
e
cs d
D K K e
Jun 07 - Mar 09
Jan 07 - Oct 08
Phys.Rev.D
79,052001 2009 .
Phys.Rev.Lett.
102,081801 2009 .
To be submitted to
Phys.Rev.D
To be submitted to
Phys.Rev.Lett.
Batbold’s thesis
• Entered Purdue: Aug 2004• Qualifying exam: Aug 2004, Preliminary exam: Oct 2006• Graduating: May 2009
The CLEO-c detector The CLEO-c detector
Studies of D Semileptonic Decay at CLEO-c Bo Xin 7Ph.D. Thesis Defense
CLEO IIIGeneral purpose symmetric detectorGeneral purpose symmetric detector
p/p = 0.6% at 800 MeV/cp/p = 0.6% at 800 MeV/c
E/E = 2% at 1 GeV, E/E = 2% at 1 GeV,
5% at 100 MeV5% at 100 MeV93% coverage 93% coverage
(charged and neutral)(charged and neutral)
Excellent electron and particle IDExcellent electron and particle ID
CLEO-c
CLEO-c CLEO III – SVX + ZD – 0.5 T
• Advantages of running at Charm threshold– Low multiplicity– High tagging efficiency
Most relevant to D semileptonic decays
Studies of D Semileptonic Decay at CLEO-c Bo Xin 8Ph.D. Thesis Defense
Analysis TechniqueAnalysis Technique Candidate events are selected by reconstructing
a D, called a tag, in several hadronic modes
Then we reconstruct the semileptonic
decay in the system recoiling from the tag.
Two key variables in the reconstruction
of a tag:
For semileptonic D :
Tagging creates a single D beam of known 4-momentum
0
0
0
0
(3770)
,
D
D
D
D K eK
22 4 2
D beam
bc beam D
E E E
M E / c p / c
��������������
| |missmissU E c P ��������������
2 2
( )
( )
ˆ where ( / ) ( )
miss beam h e brem
miss tag h e brem
tag beam D tag
E E E E E
p p p p p
p E c cm p
e+e- (3770)DD
Studies of D Semileptonic Decay at CLEO-c Bo Xin 9Ph.D. Thesis Defense
Pure DD,zero additional
particles, ~5-6 charged
particles per event
~6.6x 105 D0 and~4.8 x 105 D+ tagsreconstructed from
~5.2 x 106 DD events
We tag ~20% of the events,
compared to ~0.1% of B’s at the
Y(4S)
D D tagging at CLEO-ctagging at CLEO-c2
242 /cp/cEM Dbeambc Plots from 818/pb
DK/πe+ analysis
818 pb-1 @3770