Series: Astronomy Colloquium
Date: Wednesday 04-Oct-2023
Time: 16:05-17:00 (4:05-5:00 pm)
Location: ATL 2400
Speaker: Dr. Kishalay De (MIT)
Title: The transient mid-infrared sky: Revealing the enshrouded births, deaths and afterlives of stars through cosmic time
The growth of mass in stars and supermassive black holes (SMBHs) underpins every area of astrophysics. It is now becoming increasingly clear that short-lived transient outbursts caused by eruptive mass transfer episodes likely dominate the growth processes. Yet, direct observations remain severely limited either due to their intrinsically red emission, or absorption due to intervening dust and gas which make these phenomena invisible in optical/X-ray time domain surveys. In this talk, I will present the WISE transient pipeline -- a novel effort aimed at a systematic all-sky census of the dynamic mid-infrared sky using more than a decade of data from the NEOWISE space mission. Utilizing the highest spatial resolution images together with state-of-the art image subtraction algorithms, we have created a statistically complete sample of 15 million infrared transients in NEOWISE data. Embarking on a large ground-based follow-up program, I will present results from multi-wavelength characterization of the brightest mid-infrared transients, revealing i) a complete census of proto-stellar growth through transient outbursts, ii) a new class of dust obscured stellar mergers in low mass stars, iii) new insights into the fiery fates of close planetary systems, iv) missed tidal disruption events by SMBHs in nearby galaxies and iv) highly variable accretion outbursts in Active Galactic Nuclei in the near and distant universe.
In-person colloquia are usually preceded by espresso and ice cream at 1:45 pm outside room PSC 1150 and are followed by an informal reception at 5:15 pm in that room. Anyone interested in talking with the speaker, or being added to the colloquium announcement email list, should contact the colloquium organizer Dr. Leslie Sage. Lunch will normally be reserved for the speaker to talk to graduate students. Anyone asking a question during a talk is asked to raise their hand and be acknowledged before speaking. Contact Dr. Leslie Sage for details.
Colloquium Organizer:
Dr. Leslie Sage
Special accommodations for individuals with disabilities can be made by calling (301) 405-3001. It would be appreciated if we are notified at least one week in advance.
