Astronomy and Astrophysics Seminars
Insights into Binary Stars, Stellar Winds, and Astrophysical Plasmas from X-ray Observations of Planetary Nebulae
by Dr. Rodolfo Montez Jr. (Smithsonian Astrophysical Observatory Chandra X-ray Center)
Friday, October 20, 2017
from
to
(Asia/Kolkata)
at DAA SEMINAR ROOM ( A269 )
at DAA SEMINAR ROOM ( A269 )
TIFR
Description |
Planetary nebulae (PNe) provide textbook examples of astrophysical plasma and shock processes and provide essential constraints for theories of stellar evolution and the chemical enrichment of the universe. The varied shapes of PNe reveal the actions of interacting stellar winds from the late stages in the life of intermediate-mass stars, and growing evidence suggests that many PNe are the products of interacting binary star systems. As a result, studies of PNe can yield insight into other astrophysical objects governed by binary processes, such as, low mass X-ray binaries and Type Ia supernovae. Best known for their ten thousand degree optical line emission, the Chandra X-ray Observatory has established that a fraction of PNe display extended X-ray emission from shock-heated plasmas of a few million degrees and that the central stars harbor hotter than expected point-like emission from plasmas that reach tens of millions of degrees. I describe the discoveries, insights, and questions raised by Chandra observations of PNe with emphasis on those results gleaned from the Chandra Planetary Nebulae Survey (ChanPlaNS), which is the first systematic X-ray survey of PNe in the solar neighborhood.Planetary nebulae (PNe) provide textbook examples of astrophysical plasma and shock processes and provide essential constraints for theories of stellar evolution and the chemical enrichment of the universe. The varied shapes of PNe reveal the actions of interacting stellar winds from the late stages in the life of intermediate-mass stars, and growing evidence suggests that many PNe are the products of interacting binary star systems. As a result, studies of PNe can yield insight into other astrophysical objects governed by binary processes, such as, low mass X-ray binaries and Type Ia supernovae. Best known for their ten thousand degree optical line emission, the Chandra X-ray Observatory has established that a fraction of PNe display extended X-ray emission from shock-heated plasmas of a few million degrees and that the central stars harbor hotter than expected point-like emission from plasmas that reach tens of millions of degrees. I describe the discoveries, insights, and questions raised by Chandra observations of PNe with emphasis on those results gleaned from the Chandra Planetary Nebulae Survey (ChanPlaNS), which is the first systematic X-ray survey of PNe in the solar neighborhood. |