Nuclear and Particle Physics Colloquium (NPPC)


 

Mondays  |  Refreshments 3:30 PM  |  Talk: 4:00 PM  |  Kolker Room, 26-414

 

Committee: William Detmold, Chair ~ Daniel Harlow ~ Philip Harris ~ Or Hen

Colloquia Archives

Spring 2019

 

hosted by: Will Detmold

Lee Roberts, Boston University

Searching for Physics Beyond the Standard Model with the World’s Largest Penning Trap

Abstract: Measurements of the magnetic moments of the electron and muon were intertwined with the development of the “modern physics” of the 20th century. For the muon, this trend continues, perhaps pointing to New Physics beyond the Standard Model (BSM). The magnetic moment is along the spin,

μ=g Qe/2m ⃗s

For leptons, the factor g is greater than the Dirac value of 2 because of radiative corrections, so g =2(1+ a), or equivalently a = (g-2)/2, where a is the magnetic anomaly. While the value of the muon anomaly is dominated by the lowest-order Schwinger term α/2π≃ 0.00116⋯, it is necessary to include higher order contributions from QED, as well as contributions from the strong interaction and electroweak gauge bosons, to compare with the experimental value. The SM value now has an uncertainty of 0.3 parts per million (ppm), and the experimental value has an uncertainty of ± 0.54 ppm. The experimental value is larger than the Standard Model value by ≃ 3.7 standard deviations, which could come from new, as yet undiscovered BSM physics. To clarify this situation, a new experiment, E989 with the total error budget of ±0.14 ppm has been mounted at Fermilab and will soon begin the second data collection period. I will review the history of what we have already learned from previous (g-2) experiments, the physics reach of 989, and will report on its present status.

time:    4:00 p.m.
place:   Kolker Room (26-414)


(refreshments at 3:30 p.m.)


 

Presidents' Day Holiday - No Talk this Week

 

hosted by: Will Detmold

Annika Peter, OSU

What's Up with the Sun?

Abstract: The Sun is a popular target for dark matter searches, but there is one problem: the Sun is a mystery source of GeV-TeV gamma-rays. What we suspect is that the Sun does not shine at these energies on its own power, but because Galactic cosmic rays (CR) interact with its matter and light. By observing and modeling these interactions in and near the Sun, one may learn about CR propagation in the inner heliosphere and in the solar atmosphere, and remove this important foreground for dark matter searches. In this talk, I will present observations and a set of ongoing calculations that sharpen our understanding of how the Sun interacts with CR. From data taken with Fermi/LAT and ground-based air shower arrays, I will show that the Sun is a luminous source of gamma rays up to at least 300 GeV, with time and spatial variability that anti-correlates with the solar activity cycle. I will show how confounding these results are for any plausible model of CR-driven emission. I will show that neutrinos from the same CR-Sun interactions are a complementary probe of CR propagation, even as they are problems for dark matter searches, and highlight the prospects for IceCube and future neutrino experiments to detect this exciting new astrophysical signal.

time:    4:00 p.m.
place:   Kolker Room (26-414)


(refreshments at 3:30 p.m.)


 

hosted by: TBA

TBA

TBA

Abstract: TBA

time:    4:00 p.m.
place:   Kolker Room (26-414)


(refreshments at 3:30 p.m.)


 

hosted by: Phil Harris

Gregor Kasieczka, UHH

TBA

Abstract: TBA

time:    4:00 p.m.
place:   Kolker Room (26-414)


(refreshments at 3:30 p.m.)

 

hosted by: Or Hen

Augusto Macchiavelli, LBNL

TBA

Abstract: TBA

time:    4:00 p.m.
place:   Kolker Room (26-414)


(refreshments at 3:30 p.m.)


 

Spring Break - No Talk this Week


 

hosted by: TBA

Helen Caines, Yale University

TBA

Abstract: TBA

time:    4:00 p.m.
place:   Kolker Room (26-414)


(refreshments at 3:30 p.m.)


 

hosted by: Phil Harris

Heather Gray, UCB/LBNL

TBA

Abstract: TBA

time:    4:00 p.m.
place:   Kolker Room (26-414)


(refreshments at 3:30 p.m.


 

Patriots Day Holiday - No Talk this Week

 

hosted by: Phil Harris

Greg Landsberg, Brown University

TBA

Abstract: TBA

time:    4:00 p.m.
place:   Kolker Room (26-414)


(refreshments at 3:30 p.m.

 

hosted by: Daniel Harlow

Tien-Tien Yu, University of Oregon

TBA

Abstract: TBA

time:    4:00 p.m.
place:   Kolker Room (26-414)


(refreshments at 3:30 p.m.

 

hosted by: TBA

TBA

TBA

Abstract: TBA

time:    4:00 p.m.
place:   Kolker Room (26-414)


(refreshments at 3:30 p.m.)


 

hosted by: Iain Stewart

Claude Duhr, Université Catholique de Louvain

TBA

Abstract: TBA

time:    4:00 p.m.
place:   Kolker Room (26-414)


(refreshments at 3:30 p.m.)