Difference between revisions of "Master student Projects"

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! style="background:#3399ff;" | <font color=#ffffff> 2) Measurement of BR(B0 -> Ds+ Ds-) </font>
 
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|}
 
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''' Supervisors:''' Sevda Esen (postdoc), Niels Tuning (staf), Michele Veronesi (PhD)
 
−
 
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''' Research description: '''
 
−
 
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This project aims to discover the branching fraction of the decay B0->Ds- Ds+.
 
−
The decay B0->Ds- Ds+ is quite rare, because it occurs through the exchange of a W-boson between the
 
−
b and the d-quark of the B0-meson.
 
−
This decay proceeds via Cabibbo-suppressed W-exchange and
 
−
has not yet been observed; theoretical calculations predict
 
−
a branching fraction at the order of 10^-5 with a best
 
−
experimental upper limit of 3.6x10^-5.
 
−
 
−
A measurement of the decay rate of B0 ->  Ds+Ds- relative to
 
−
that of B0 -> D+D- can provide an estimate of the W-exchange contribution
 
−
to the latter decay, a crucial piece of information for extracting
 
−
the CKM angle gamma from B0 -> D(*)D(*).
 
−
 
−
The aim is to determine the relative branching fraction of  B0->Ds+Ds- with respect to B0->Ds+D- decays
 
−
(which has the best known branching ratio at present, (7.2 +- 0.8)x10^-3),
 
−
in close collaboration with the PhD.
 
−
The aim is that this project results in a journal publication on behalf of the LHCb collaboration.
 
−
For this project computer skills are needed.
 
−
The ROOT programme and C++ and/or Python macros are used.
 
−
This is a project that is closely related to previous analyses in the group.
 
−
Weekly video meetings with CERN coordinate the efforts with in the LHCb collaboration.
 
−
 
−
''' Relevant information: '''
 
−
 
−
[1] M.Jung and S.Schacht,
 
−
"Standard Model Predictions and New Physics Sensitivity in B -> DD Decays"
 
−
https://arxiv.org/pdf/1410.8396.pdf
 
−
 
−
[2] L.Bel, K.de Bruyn, R. Fleischer, M.Mulder, N.Tuning,
 
−
"Anatomy of B -> DD Decays"
 
−
https://arxiv.org/pdf/1505.01361.pdf
 
−
 
−
[3] A.Zupanc et al [Belle Collaboration]
 
−
"Improved measurement of B0 -> DsD+ and search for B0 -> Ds+Ds at Belle"
 
−
https://arxiv.org/pdf/hep-ex/0703040.pdf
 
−
 
−
[4] B.Aubert et al. [Babar Collaboration]
 
−
"Search for the W-exchange decays B0 -> DD+"
 
−
https://arxiv.org/pdf/hep-ex/0510051.pdf
 
−
 
−
[5] R.Aaij et al. [LHCb Collaboration],
 
−
"First observations of B0s -> D+D, Ds+D and D0D0 decays"
 
−
https://arxiv.org/pdf/1302.5854.pdf
 
−
 
−
 
−
 
−
{| border="1" cellpadding="2" cellspacing="0"
 
−
|-
 
−
! style="background:#3399ff;" | <font color=#ffffff> 3) Measurement of relative ratio of B+ -> D0D+ and B+ -> D0Ds decays </font>
 
−
|}
 
−
 
−
''' Supervisors:''' Sevda Esen (postdoc), Niels Tuning (staf), Michele Veronesi (PhD)
 
−
 
−
''' Research description: '''
 
−
 
−
This decay is closely related to B0->Ds- Ds+ (see above), and close collaboration between the two master projects is foreseen.
 
−
The decay mode B+->D0D+ is expected to be dominated by tree diagrams with some additional
 
−
contributions from penguin diagrams. Assuming SU(3) symmetry,
 
−
measurement of its branching fraction relative to Cabibbo-favored
 
−
B+->D0D will enable better understanding of penguin contributions
 
−
to the CP violating mixing phase.
 
−
 
−
''' Relevant information: '''
 
−
 
−
[1] L.Bel, K.de Bruyn, R. Fleischer, M.Mulder, N.Tuning,
 
−
"Anatomy of B -> DD Decays"
 
−
https://arxiv.org/pdf/1505.01361.pdf
 
−
 
−
[2] R.Aaij et al. [LHCb Collaboration],
 
−
"First observations of B0s -> D+D, Ds+D and D0D0 decays"
 
−
https://arxiv.org/pdf/1302.5854.pdf
 
−
 
−
[3] PDG: http://pdglive.lbl.gov/BranchingRatio.action?desig=261&parCode=S041
 
  
  
Line 268: Line 184:
 
OLD PROJECTS  
 
OLD PROJECTS  
 
==============
 
==============
−
  Commented out Nov 2014 by Niels (Elise is on this project)
+
-->
 +
 
 +
<!-- ################################################# -->
 +
<!-- Commented out by Niels Apr 2020.
 +
 
 +
{| border="1" cellpadding="2" cellspacing="0"
 +
|-
 +
! style="background:#3399ff;" | <font color=#ffffff> 2) Measurement of BR(B0 -> Ds+ Ds-) </font>
 +
|}
 +
''' Supervisors:''' Sevda Esen (postdoc), Niels Tuning (staf), Michele Veronesi (PhD)
 +
''' Research description: '''
 +
 
 +
This project aims to discover the branching fraction of the decay B0->Ds- Ds+.
 +
The decay B0->Ds- Ds+ is quite rare, because it occurs through the exchange of a W-boson between the
 +
b and the d-quark of the B0-meson.
 +
This decay proceeds via Cabibbo-suppressed W-exchange and
 +
has not yet been observed; theoretical calculations predict
 +
a branching fraction at the order of 10^-5 with a best
 +
experimental upper limit of 3.6x10^-5.
 +
 
 +
A measurement of the decay rate of B0 -> Ds+Ds- relative to
 +
that of B0 -> D+D- can provide an estimate of the W-exchange contribution
 +
to the latter decay, a crucial piece of information for extracting
 +
the CKM angle gamma from B0 -> D(*)D(*).
 +
 
 +
The aim is to determine the relative branching fraction of  B0->Ds+Ds- with respect to B0->Ds+D- decays
 +
(which has the best known branching ratio at present, (7.2 +- 0.8)x10^-3),
 +
in close collaboration with the PhD.
 +
The aim is that this project results in a journal publication on behalf of the LHCb collaboration.
 +
For this project computer skills are needed.
 +
The ROOT programme and C++ and/or Python macros are used.
 +
This is a project that is closely related to previous analyses in the group.
 +
Weekly video meetings with CERN coordinate the efforts with in the LHCb collaboration.
 +
 
 +
''' Relevant information: '''
 +
 
 +
[1] M.Jung and S.Schacht,
 +
"Standard Model Predictions and New Physics Sensitivity in B -> DD Decays"
 +
https://arxiv.org/pdf/1410.8396.pdf
 +
[2] L.Bel, K.de Bruyn, R. Fleischer, M.Mulder, N.Tuning,
 +
"Anatomy of B -> DD Decays"
 +
https://arxiv.org/pdf/1505.01361.pdf
 +
[3] A.Zupanc et al [Belle Collaboration]
 +
"Improved measurement of B0 -> DsD+ and search for B0 -> Ds+Ds at Belle"
 +
https://arxiv.org/pdf/hep-ex/0703040.pdf
 +
[4] B.Aubert et al. [Babar Collaboration]
 +
"Search for the W-exchange decays B0 -> DD+"
 +
https://arxiv.org/pdf/hep-ex/0510051.pdf
 +
[5] R.Aaij et al. [LHCb Collaboration],
 +
"First observations of B0s -> D+D, Ds+D and D0D0 decays"
 +
https://arxiv.org/pdf/1302.5854.pdf
 +
 
 +
 
 +
{| border="1" cellpadding="2" cellspacing="0"
 +
|-
 +
! style="background:#3399ff;" | <font color=#ffffff> 3) Measurement of relative ratio of B+ -> D0D+ and B+ -> D0Ds decays </font>
 +
|}
 +
''' Supervisors:''' Sevda Esen (postdoc), Niels Tuning (staf), Michele Veronesi (PhD)
 +
''' Research description: '''
 +
 
 +
This decay is closely related to B0->Ds- Ds+ (see above), and close collaboration between the two master projects is foreseen.
 +
The decay mode B+->D0D+ is expected to be dominated by tree diagrams with some additional
 +
contributions from penguin diagrams. Assuming SU(3) symmetry,
 +
measurement of its branching fraction relative to Cabibbo-favored
 +
B+->D0D will enable better understanding of penguin contributions
 +
to the CP violating mixing phase.
 +
 
 +
''' Relevant information: '''
 +
 
 +
[1] L.Bel, K.de Bruyn, R. Fleischer, M.Mulder, N.Tuning,
 +
"Anatomy of B -> DD Decays"
 +
https://arxiv.org/pdf/1505.01361.pdf
 +
[2] R.Aaij et al. [LHCb Collaboration],
 +
"First observations of B0s -> D+D, Ds+D and D0D0 decays"
 +
https://arxiv.org/pdf/1302.5854.pdf
 +
[3] PDG: http://pdglive.lbl.gov/BranchingRatio.action?desig=261&parCode=S041
 +
 
 +
-->
 +
<!-- ################################################# -->
 +
 
 +
<!-- ################################################# -->
 +
<!-- Commented out Nov 2014 by Niels (Elise is on this project)
  
 
{| border="1" cellpadding="2" cellspacing="0"
 
{| border="1" cellpadding="2" cellspacing="0"

Revision as of 15:59, 14 April 2020

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