BEGIN:VCALENDAR VERSION:2.0 X-WR-CALNAME:EventsCalendar PRODID:-//hacksw/handcal//NONSGML v1.0//EN CALSCALE:GREGORIAN BEGIN:VTIMEZONE TZID:America/New_York LAST-MODIFIED:20240422T053451Z TZURL:https://www.tzurl.org/zoneinfo-outlook/America/New_York X-LIC-LOCATION:America/New_York BEGIN:DAYLIGHT TZNAME:EDT TZOFFSETFROM:-0500 TZOFFSETTO:-0400 DTSTART:19700308T020000 RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=2SU END:DAYLIGHT BEGIN:STANDARD TZNAME:EST TZOFFSETFROM:-0400 TZOFFSETTO:-0500 DTSTART:19701101T020000 RRULE:FREQ=YEARLY;BYMONTH=11;BYDAY=1SU END:STANDARD END:VTIMEZONE BEGIN:VEVENT CATEGORIES:College of Engineering DESCRIPTION:Abstract: 78Ni is a doubly magic nucleus far from stability, wh ich was identiﬁed as an early “waiting point” for r-process nucleosy nthesis. Recent measurements indicate that decays of nuclei beyond N=50 ca n be understood as the decay of the 78Ni core, with the valence neutrons o utside N=50 playing only a spectator role (Madurga et al.). In this experi ment, the focus was extended to also study the decay of nearby 79Cu. The N =50 isotones near 78Ni were studied for the ﬁrst time using total-absorp tion spectroscopy, with the beta-decay strength distribution measured at t he FRIB Decay Station initiator (FDSi). The experiment employed the Modula r Total Absorption Spectrometer (MTAS) to measure complete γ-ray cascades following decays to neutron-bound states in 79Cu. The isotopes were impla nted at the second focal plane of the FDSi into a Yttrium Ortho-silicate(Y SO) segmented scintillator detector system inside the MTAS. An ion-beta co rrelation was performed on the collected isotopes, and the optimal correla tion radius was found to acquire the best signal-to-background ratio. Furt her analysis will be performed using the Geant4 simulations to obtain the MTAS response functions. A complete deconvolution of MTAS spectra allows f or the extraction of β-decay strength distribution for 79Cu. The experime ntal ﬁndings will be compared with the nuclear shell models to study the evolution of the N=50 shell closure in the region. Biography: Prabodha ea rned his BSc degree in physics from the University of Peradeniya, Sri Lank a. After that, he began an MS in physics at UMass Dartmouth and graduated in 2023. Under Prof. Robert Fisher, he researched viscous evolution in Ast rophysical disks. That same year, he started his PhD in physics at the Uni versity of Tennessee, Knoxville, and is currently a fourth-year PhD studen t there. After working in computational astrophysics, Prabodha shifted his interests to Experimental Nuclear physics, where he focuses on nuclear st ructure and nuclear astrophysics. His current research focuses on studying the decay of neutron-rich isotopes near the 78Ni shell closure, and Prof. Robert Grzywacz advises him.\nEvent page: https://www.umassd.edu/events/c ms/10-8-26-physics-seminar.php\nEvent link: https://umassd.zoom.us/j/96467 854751?pwd=VNpsXZMMdIRO6I2j3Mo5QOcNNb1U2v.1 X-ALT-DESC;FMTTYPE=text/html:

Abstract:

⁷⁸ Ni is a doubly magic nucleus far from stability\, which was identiﬁed as an early “waiting point” for r-process nucleosynthesis. Recent measur ements indicate that decays of nuclei beyond N=50 can be understood as the decay of the ⁷⁸Ni core\, with the valence neutrons outside N=5 0 playing only a spectator role (Madurga et al.). In this experiment\, the focus was extended to also study the decay of nearby ⁷⁹Cu. The N=50 isotones near ⁷⁸Ni were studied for the ﬁrst time using total-absorption spectroscopy\, with the beta-decay strength distribution measured at the FRIB Decay Station initiator (FDSi). The experiment emplo yed the Modular Total Absorption Spectrometer (MTAS) to measure complete γ-ray cascades following decays to neutron-bound states in ⁷⁹C u. The isotopes were implanted at the second focal plane of the FDSi into a Yttrium Ortho-silicate(YSO) segmented scintillator detector system insid e the MTAS. An ion-beta correlation was performed on the collected isotope s\, and the optimal correlation radius was found to acquire the best signa l-to-background ratio. Further analysis will be performed using the Geant4 simulations to obtain the MTAS response functions. A complete deconvoluti on of MTAS spectra allows for the extraction of β-decay strength distribu tion for ⁷⁹Cu. The experimental ﬁndings will be compared with the nuclear shell models to study the evolution of the N=50 shell closure in the region.

Biography:

Prabodha earned his BSc degree in physics from the University of Peradeniya\, Sri Lanka. After that\, he began an MS in physics at UMass Dartmouth and graduated in 2023. Under Pro f. Robert Fisher\, he researched viscous evolution in Astrophysical disks. That same year\, he started his PhD in physics at the University of Tenne ssee\, Knoxville\, and is currently a fourth-year PhD student there. After working in computational astrophysics\, Prabodha shifted his interests to Experimental Nuclear physics\, where he focuses on nuclear structure and nuclear astrophysics. His current research focuses on studying the decay o f neutron-rich isotopes near the 78Ni shell closure\, and Prof. Robert Grz ywacz advises him.

Event page: https://www.umassd.edu/events/cms/10-8- 26-physics-seminar.php
Event link: https://umassd.zoom.us /j/96467854751?pwd=VNpsXZMMdIRO6I2j3Mo5QOcNNb1U2v.1

DTSTAMP:20260929T214839 DTSTART;TZID=America/New_York:20261008T140000 DTEND;TZID=America/New_York:20261008T153000 LOCATION:Zooom SUMMARY;LANGUAGE=en-us:Physics Seminar UID:bf8cb0faa6f519cf3b89ffd55d2ee4ea@www.umassd.edu END:VEVENT END:VCALENDAR