Institute for Nuclear and Particle Astrophysics (INPA) at LBNL
The INPA Seminar weekly talks are on Fridays, starting at 12:00 pm, unless informed otherwise. The seminar talk starts with a brief presentation of the weekly scientific news. Typically, the talks conclude by 1:00 pm. The seminars are held in the Sessler Conference Room, located in Bldg. 50A- 5132.
The committee members are:
The seminar schedule for the Institute for Nuclear and Particle Astrophysics (INPA) is tentative and becomes final a few days before the Friday talk.
Please send all suggestions for future INPA talks and speakers to the INPA Committee.
To be added to the INPA News Mailing List, please contact Erica Hall.
- This event has passed.
VIRTUAL INPA SEMINAR – Luca Pagani (UC Davis)
May 29, 2020 @ 12:00 pm - 1:00 pm
Speaker: Luca Pagani (UC Davis)
Title: Recent results from the ACED and the ARTIE experiments
Abstract:
Liquid argon is becoming a popular medium for particle detection, with applications ranging from low-background dark matter searches to high-energy neutrino detection. Because neutrons represent both an important source of background (e.g., for dark matter experiments) and a product of signal events (e.g., neutrino-induced spallation neutrons), a good understanding of their interactions in argon is a requirement for precision physics measurements. Despite being one of the most basic quantities needed to describe low-energy neutron transport, the neutron cross section on argon is not clearly understood. In particular, the existing activation measurements for the thermal neutron capture cross section show significant disagreements. Moreover, in the energy range 40-70 keV theory predicts an anti-resonance in the $^{40}$Ar cross section near $57$\,keV, but the existing data, coming from an experiment performed in the 90s (Winters. et al.), does not support this. To resolve these disagreements, two experiments were performed using a time of flight neutron beam at Los Alamos National Laboratory. The Argon Capture Experiment at DANCE (ACED) first measured the differential cross section of $^{40}$Ar$(n,\gamma)^{41}$Ar using the Detector for Advanced Neutron Capture Experiments (DANCE), a $\sim$4$\pi$ gamma spectrometer. A fit to the differential cross section from $0.015-0.15$\,eV, assuming a $1/v$ energy dependence, yields $\sigma^{2200} = 673 \pm 26 \text{ (stat.)} \pm 59 \text{(sys.)}$\,mb. Then, the Argon Resonance Transmission Interaction Experiment (ARTIE) measured the transmission coefficient for neutrons through a thick ($\sim 3$\,atoms/b) liquid natural argon target in the energy range 40-70 keV. This measurements are crucial for the Deep Underground Neutrino Experiment (DUNE) since allow a viable means of calibration and a deeper understanding of signals and backgrounds for the low energy science program.
Join Zoom Meeting
https://lbnl.zoom.us/j/97119161552
Meeting ID: 971 1916 1552
INPA guests from campus can now come to the lab early on Fridays. The INPA Common Room (50-5026) is reserved for our guests from 10:00 a.m. to 12:00 noon and from 1 p.m. to 5 p.m. Note that the seminars are now held in 50A-5132 to accommodate a more significant number of attendees.
CPTea Series (also known as INPA Tea Series)
The Physics Division CPTea Series invites you to an In-Person Tea Series 1st Friday of every month at 3:30 pm INPA Conference Room 50-5026.
Everyone is welcome to attend the open forum. Tea and light refreshments will be served.
INPA Common Room (50-5026)
Fridays
3:30 pm
Access to the Lab
For a shuttle pass, please email Erica Hall. The pass is only valid for the day of the seminar.