DATE HAS BEEN CHANGED (FROM AUGUST 8th)
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Future presenters
Featured presentation
"A Big Survey Approach to Addressing the Mystery of Magnetic Fields in Massive Stars"
(details below)
(details below)
Yosemite Star Party Re-Cap
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Adjournment
More about our feature presentation: our guest presenter is S. Drew Chojnowski, Postdoctoral Researcher, NASA Ames Research Center. Here is detailed description of his presentation:
For well over 60 years it has been known that, when compared to normal main sequence stars, a non-negligible fraction of late-B-type and early-A-type stars exhibit anomalously high surface abundances of heavy elements that are empirically linked to strong, global magnetic fields. Whereas lower mass stars (<1.5 solar masses) are known to generate their considerably weaker and always transient magnetic fields via the solar dynamo process in their convective outer envelopes, theory predicts that the chemically peculiar Ap/Bp stars should have fully radiative envelopes in which magnetic fields cannot be generated. The fact that Ap/Bp stars have magnetic fields at all, let alone fields that can reach extraordinary strengths of up to 34 kilo-Gauss (in the case of Babcock’s Star), makes them one of the longest running mysteries of stellar astrophysics. Observations over the past few decades have indicated an unusual dearth of short-period binary systems among Ap/Bp stars, and this has led to speculation about them being formed as a result of binary mergers. Although recent modeling efforts confirmed that mergers can in fact generate strong, built-in magnetic fields, there are to date no confirmed cases of binary mergers in any kind of non-degenerate star whatsoever, Ap/Bp stars included. This talk will focus on my efforts to address the mystery of magnetic fields in Ap/Bp stars via big survey data from SDSS/APOGEE and TESS.
Acronyms:
SDSS = Sloan Digital Sky Survey
APOGEE = Apache Point Observatory Galactic Evolution Experiment (a sub-survey of SDSS)
TESS = Transiting Exoplanet Survey Satellite
Date: Thursday, August 15, 2024
Time: 7 p.m. - 8:30 p.m. Pacific
Location:
Monterey Institute for Research in Astronomy
200 8th St
Marina, CA 93933
