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Lunchtime Seminars

Tuesdays ~ 12pm ~ Kolker Room, 26-414

 

Committee:
Gunther Roland, Chair ~ Doug Hasell~ Paolo Zuccon



 

September 9, 2014

 


Matteo Cremonsi, University of Chicago

Observation of s-channel single-top-quark production at the Tevatron

Abstract: Studies of the properties of the top quark are being actively pursued at the Fermilab's Tevatron and at the CERN LHC. Besides top-antitop pair production by strong interaction, which is the most common production mechanism, the less common single-top production via electroweak interaction is now being tackled.

 

Collisions that produce a single top quark through the weak nuclear force are rarer, and the events are much less distinctive than top pairs. According to the Standard Model, single-top production can be induced by several amplitudes. Production through the exchange of a virtual W boson in the s-channel is very hard to isolate. This production channel is barely accessible at the Tevatron and is presently out of reach at the higher energy LHC. On the other hand, new physics effects might most readily show up in this channel. The observation of this production channel was one of the ultimate goals of the Tevatron.

 

The analysis methods adopted by the CDF and D0 experiments to isolate s-channel single-top quark production will be described. The speaker will illustrate the main analysis features, underling the challenges and describing the techniques employed in order to accomplish such a difficult task. The CDF and D0 results will be shown, claiming discovery by combining them.

time:    Noon
place:   Kolker Room (26-414)

(Lunch will be served.)



September 16, 2014

 


Ross Corliss, MIT

Looking for Dark Light

Abstract: At this point, the existence of every particle in the Standard Model has been experimentally confirmed, but we know this is not the end of the story. The DarkLight experiment will search for a beyond-the-standard-model dark photon, A', that could shed light on some apparent shortcomings, both the large-scale absence of dark matter in the theory, and the small-scale deviation of the muon magnetic dipole moment calculation from recent measurements. Using the intense electron beam at Jefferson Lab's Energy Recovering Linac (the former FEL), DarkLight will look for A' production by reconstructing complete final states in extremely high-rate (1036/cm2/s) electron-proton collisions. High-speed readout will make all of this data available, allowing DarkLight to probe several different A' signatures. I will discuss the experimental design and the challenges of operating at such high rates, as well as how these measurements will fit into the ongoing search for phenomena outside of the Standard Model.

time:    Noon
place:   Kolker Room (26-414)

(Lunch will be served.)



September 23, 2014


Alexander Himmel, Duke University

Short-baseline Oscillation Measurements with Electron Neutrinos at T2K

Abstract: The T2K experiment has searched for disappearance at a short baseline in the electron neutrino component of the JPARC neutrino beam consistent with oscillations to a sterile neutrino. Anomalies in the previous measurements of electron neutrinos and antineutrinos from reactors and radioactive sources are not explained by oscillations among three neutrinos, but are instead compatible with the existence of a fourth neutrino mass eigenstate with a mass-splitting at or above 1 eV2 relative to the active neutrinos. These anomalies are tested with the T2K near detector, ND280. Located 280 m from the hadron production point with an average electron-neutrino energy of 500 MeV, this experiment is sensitive to sterile oscillations with a mass difference of ~2 eV2. The analysis of the electron-neutrino interaction rates, combined with a good understanding of the backgrounds allows us to constrain the oscillation parameter space and to reject some regions of parameter space allowed by the gallium and reactor anomalies.

time:    Noon
place:   Kolker Room (26-414)

(Lunch will be served.)



September 30, 2014


To be determined

 

time:    Noon
place:   Kolker Room (26-414)

(Lunch will be served.)



October 7, 2014


To be determined

 

time:    Noon
place:   Kolker Room (26-414)

(Lunch will be served.)



October 14, 2013

week of COLUMBUS DAY – No Lunchtime Seminar



October 21, 2014


To be determined

 

time:    Noon
place:   Kolker Room (26-414)

(Lunch will be served.)



October 28, 2014


To be determined

 

time:    Noon
place:   Kolker Room (26-414)

(Lunch will be served.)



November 4, 2014


To be determined

 

time:    Noon
place:   Kolker Room (26-414)

(Lunch will be served.)



November 11, 2013

week of VETERANS' DAY – No Lunchtime Seminar



November 18, 2014


To be determined

 

time:    Noon
place:   Kolker Room (26-414)

(Lunch will be served.)



November 25, 2014


To be determined

 

time:    Noon
place:   Kolker Room (26-414)

(Lunch will be served.)



December 2, 2014


To be determined

 

time:    Noon
place:   Kolker Room (26-414)

(Lunch will be served.)



December 9, 2014


To be determined

 

time:    Noon
place:   Kolker Room (26-414)

(Lunch will be served.)