Difference between revisions of "Master student Projects"

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=== Master projects in the Nikhef B-physics group ===
 
=== Master projects in the Nikhef B-physics group ===
  
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TEMPLATE
  
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|-
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! style="background:#3399ff;" | <font color=#ffffff> 1) Title </font>
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'''Supervisor''' : S.Taff (staff)
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'''Research Description:'''
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Abstract
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''' Relevant information: '''
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[1]  [https://arxiv.org/abs/1507.03414 arXiv:1507.03414] (thesis or paper)
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END TEMPLATE
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{| border="1" cellpadding="2" cellspacing="0"
 
{| border="1" cellpadding="2" cellspacing="0"
 
|-
 
|-
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! style="background:#3399ff;" | <font color=#ffffff> 1) Searches for new pentaquarks </font>
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! style="background:#3399ff;" | <font color=#ffffff> 1) Measurement of delta md </font>
 
|}
 
|}
  
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'''Supervisor''' : P. Koppenburg (staff)
+
'''Supervisor''' : Niels Tuning (staff), Emmy Gabriel (postdoc), Michele Veronesi (PhD)
  
 
'''Research Description:'''
 
'''Research Description:'''
  
−
In 2015 LHCb surprisingly discovered states containing five quarks, called Pc+ pentaquarks. Such particles question our understanding of confinement, the principle that forces quarks to remain in a single hadron. Which hadrons are allowed and which are not? The pentaquarks were found in the decay of the Lambda_b baryon to a Pc+ and a kaon, and Pc+ to a J/psi and a proton. This project aims at studying other similar but yet unobserved decays which could reveal the presence of the know Pc+, or yet unknown pentaquarks. The student will optimise a selection for finding such a decay in LHCb data using machine learning techniques.  
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The decay B0->D-pi+ is very abundant in LHCb, and therefore ideal to study the oscillation frequency
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delta md, with which B0 mesons oscillate into anti-B0 mesons, and vice versa.
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This process proceeds through a so-called box diagram which might hide new yet-undiscovered particles.
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Recently, it has been realized that value of delta md is in tension with the valu of CKM-angle gamma,
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triggering renewed interest in this measurement.
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Our group at Nikhef has 10 years experience in the analysis of B->Dh decays.
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This analysis may lead to a publication on behalf of the LHCb collaboration.
  
 
''' Relevant information: '''
 
''' Relevant information: '''
  
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[1]  [https://arxiv.org/abs/1507.03414 arXiv:1507.03414] (the pentaquark paper)
 
  
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[2] [https://arxiv.org/abs/1406.0755 arXiv:1406.0755] (a paper by P. Koppenburg similar to what the project could lead to).
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[1] [https://arxiv.org/abs/1812.06963 arXiv:1812.06963] M. Blanke, A. Buras, Emerging delta md Anomaly from Tree-Level Determinations of |Vcb| and the angle gamma
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[2] [https://arxiv.org/abs/1911.07856 arXiv:1911.07856] D. King, A. Lenz, Th. Rauh, |Vcb| and gamma from mixing
 +
 
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[3] [https://indico.nikhef.nl/event/1379/contribution/1/material/slides/0.pdf talk] N. Tuning, CKM unitarity and B mixing
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[4] [https://arxiv.org/abs/1210.6750 arXiv:1210.6750] LHCb coll.,
 +
 +
 
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[5] [https://arxiv.org/abs/1805.03448 arXiv:1805.03448] LHCb coll.,
 +
 +
 
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{| border="1" cellpadding="2" cellspacing="0"
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|-
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! style="background:#3399ff;" | <font color=#ffffff> 2) Searching for CPT violation </font>
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|}
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'''Supervisor''' : Niels Tuning (staff), Emmy Gabriel (postdoc), Michele Veronesi (PhD)
 +
 
 +
'''Research Description:'''
 +
 
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CPT symmetry is closely linked to Lorentz symmetry, and any violation
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would revolutionize science. There are possibilities though that supergravity could
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cause CPT violating effects in the system of neutral mesons.
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The precise study of B0s oscillations in the abundant Bs->Dspi decays can
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give the most stringent limits on Im(z) to date.
 +
 
 +
Our group at Nikhef has 10 years experience in the analysis of B->Dh decays.
 +
This analysis may lead to a publication on behalf of the LHCb collaboration.
  
 +
''' Relevant information: '''
  
 +
[1]  [https://arxiv.org/abs/1603.04804 arXiv:1603.04804] LHCb coll.,
 +
Search for violations of Lorentz invariance and CPT symmetry in B0(s) mixing
  
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[2] [https://arxiv.org/abs/1407.1269 arXiv:1407.1269] J. van Tilburg and M. van Veghel,
 +
Status and prospects for CPT and Lorentz invariance violation searches in neutral meson mixing
  
  
 
{| border="1" cellpadding="2" cellspacing="0"
 
{| border="1" cellpadding="2" cellspacing="0"
 
|-
 
|-
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! style="background:#3399ff;" | <font color=#ffffff> 5) A Scintillator Fibers Tracker </font>
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! style="background:#3399ff;" | <font color=#ffffff> 3) BR(B0->D-pi+) and fd/fu with B+->D0pi+ </font>
 
|}
 
|}
  
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''' Supervisors:''' Antonio Pellegrino
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'''Supervisor''' : Niels Tuning (staff), Emmy Gabriel (postdoc), Michele Veronesi (PhD)
 +
 
 +
'''Research Description:'''
 +
 
 +
The abundant decay B0->D-pi+ is often used as normalization channel, given its
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clean signal, and well-known branching fraction, as measured by the B-factories.
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However, this branching fraction can be determined more precisely, when comparing
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to the decay B+->D0pi+ , which has a twice better precision.
 +
 
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In addition, the production of B0 and B+ mesons is often assumed to be equal,
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based on isospin symmetry. The study of B+->D0pi+ and B0->D-pi+ allows for the
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first measurement of this ratio, fd/fu.
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 +
Our group at Nikhef has 10 years experience in the analysis of B->Dh decays.
 +
This analysis may lead to a publication on behalf of the LHCb collaboration.
  
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''' Research description: '''
+
''' Relevant information: '''
  
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The LHCb collaboration is upgrading the present tracking system
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[1]  [https://cds.cern.ch/record/2636716/files/CERN-THESIS-2018-137.pdf CERN-THESIS-2018-137] J. Butter,  
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constructing a new tracker based on scintillating fibers combined
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Branching fraction measurement of B0->D+s pi?
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with silicon photo-multipliers (SiPM): the SciFi Tracker!
 
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Nikhef plays a key role in the project, as we will build the
 
−
SciFi fibers modules, the cold-box enclosure housing the SiPMs,
 
−
and a large part of the on-detector electronics. In all these
 
−
areas, interesting test hardware and software has to be realized,
 
−
and several research topics for a Master project are available,
 
−
taking the student in contact with state-of-the-art particle detectors,
 
−
in a large team of physicists and engineers. Possible collaborations
 
−
with the Nikhef R&D group can also be envisaged.
 
  
  
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{| border="1" cellpadding="2" cellspacing="0"
 
{| border="1" cellpadding="2" cellspacing="0"
 
|-
 
|-
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! style="background:#3399ff;" | <font color=#ffffff> 6) The Z forward backward asymmetry </font>
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! style="background:#3399ff;" | <font color=#ffffff> 5) Searches for new pentaquarks </font>
 
|}
 
|}
  
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''' Supervisors:''' Wouter Hulsbergen
+
'''Supervisor''' : P. Koppenburg (staff)
 +
 
 +
'''Research Description:'''
  
−
''' Research description: '''
+
In 2015 LHCb surprisingly discovered states containing five quarks, called Pc+ pentaquarks. Such particles question our understanding of confinement, the principle that forces quarks to remain in a single hadron. Which hadrons are allowed and which are not? The pentaquarks were found in the decay of the Lambda_b baryon to a Pc+ and a kaon, and Pc+ to a J/psi and a proton. This project aims at studying other similar but yet unobserved decays which could reveal the presence of the know Pc+, or yet unknown pentaquarks. The student will optimise a selection for finding such a decay in LHCb data using machine learning techniques.
  
−
The forward backward asymmetry of Z->mumu decays probes the standard model weak mixing angle, providing a strong test of the standard model. A dominating systematic uncertainty in this measurement is the affect of detector misalignments. In this project Z->mumu events are used to improve the detector alignment and thereby increase the precision of the run-2 measurements.
+
''' Relevant information: '''
  
 +
[1]  [https://arxiv.org/abs/1507.03414 arXiv:1507.03414] (the pentaquark paper)
  
 +
[2] [https://arxiv.org/abs/1406.0755 arXiv:1406.0755] (a paper by P. Koppenburg similar to what the project could lead to).
  
  
 
{| border="1" cellpadding="2" cellspacing="0"
 
{| border="1" cellpadding="2" cellspacing="0"
 
|-
 
|-
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! style="background:#3399ff;" | <font color=#ffffff> 9) Measurement of the relative efficiency of muons and electrons with J/psi->ll decays </font>
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! style="background:#3399ff;" | <font color=#ffffff> 6) Measurement of the relative efficiency of muons and electrons with J/psi->ll decays </font>
 
|}
 
|}
  
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{| border="1" cellpadding="2" cellspacing="0"
 
{| border="1" cellpadding="2" cellspacing="0"
 
|-
 
|-
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! style="background:#3399ff;" | <font color=#ffffff> 10) Very rare decays of B mesons</font>
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! style="background:#3399ff;" | <font color=#ffffff> 7) Very rare decays of B mesons</font>
 
|}
 
|}
  
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{| border="1" cellpadding="2" cellspacing="0"
 
{| border="1" cellpadding="2" cellspacing="0"
 
|-
 
|-
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! style="background:#3399ff;" | <font color=#ffffff> 11) Measurement of Central Exclusive Production Rates of Chi_c using converted photons in LHCb. </font>
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! style="background:#3399ff;" | <font color=#ffffff> 8) Measurement of Central Exclusive Production Rates of Chi_c using converted photons in LHCb. </font>
 
|}
 
|}
  
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{| border="1" cellpadding="2" cellspacing="0"
 
{| border="1" cellpadding="2" cellspacing="0"
 
|-
 
|-
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! style="background:#3399ff;" | <font color=#ffffff> 12) Optimization studies for Vertex detector at the High Lumi LHCb </font>
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! style="background:#3399ff;" | <font color=#ffffff> 9) Optimization studies for Vertex detector at the High Lumi LHCb </font>
 
|}
 
|}
  
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{| border="1" cellpadding="2" cellspacing="0"
 
{| border="1" cellpadding="2" cellspacing="0"
 
|-
 
|-
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! style="background:#3399ff;" | <font color=#ffffff> 13) Measurement of charge multiplication in heavily irradiated sensors </font>
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! style="background:#3399ff;" | <font color=#ffffff> 10) Measurement of charge multiplication in heavily irradiated sensors </font>
 
|}
 
|}
  
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==============
 
==============
 
-->
 
-->
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<!-- ################################################# -->
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<!--
 +
| border="1" cellpadding="2" cellspacing="0"
 +
|-
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! style="background:#3399ff;" | <font color=#ffffff> 5) A Scintillator Fibers Tracker </font>
 +
|}
 +
''' Supervisors:''' Antonio Pellegrino
 +
''' Research description: '''
 +
The LHCb collaboration is upgrading the present tracking system
 +
constructing a new tracker based on scintillating fibers combined
 +
with silicon photo-multipliers (SiPM): the SciFi Tracker!
 +
Nikhef plays a key role in the project, as we will build the
 +
SciFi fibers modules, the cold-box enclosure housing the SiPMs,
 +
and a large part of the on-detector electronics. In all these
 +
areas, interesting test hardware and software has to be realized,
 +
and several research topics for a Master project are available,
 +
taking the student in contact with state-of-the-art particle detectors,
 +
in a large team of physicists and engineers. Possible collaborations
 +
with the Nikhef R&D group can also be envisaged.
 +
-->
 +
<!-- ################################################# -->
 +
  
 
<!-- ################################################# -->
 
<!-- ################################################# -->
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''' Supervisors:''' Wouter Hulsbergen
 
''' Supervisors:''' Wouter Hulsbergen
 
''' Research description: '''
 
''' Research description: '''
−
 
  
  
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''' Supervisors:''' Wouter Hulsbergen
 
''' Supervisors:''' Wouter Hulsbergen
 
''' Research description: '''
 
''' Research description: '''
 +
In certain parts of their parameter space Hidden Valley theories predict upsilon decays to two new dark sector particles that subsequently decay into two muons. These particles may or may not be long-lived. In this project we search for such events in LHCb run-2 data using the Turbo stream.
 +
 +
 +
{| border="1" cellpadding="2" cellspacing="0"
 +
|-
 +
! style="background:#3399ff;" | <font color=#ffffff> 6) The Z forward backward asymmetry </font>
 +
|}
 +
''' Supervisors:''' Wouter Hulsbergen
 +
''' Research description: '''
 +
The forward backward asymmetry of Z->mumu decays probes the standard model weak mixing angle, providing a strong test of the standard model. A dominating systematic uncertainty in this measurement is the affect of detector misalignments. In this project Z->mumu events are used to improve the detector alignment and thereby increase the precision of the run-2 measurements.
  
−
In certain parts of their parameter space Hidden Valley theories predict upsilon decays to two new dark sector particles that subsequently decay into two muons. These particles may or may not be long-lived. In this project we search for such events in LHCb run-2 data using the Turbo stream.
 
  
 
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Revision as of 11:15, 6 May 2020

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