AAVSO webinar, with Dr. Steve Howell (NASA) and Dr. Juan Echevarría (UNAM)
March 13 @ 2:00 pm - 4:00 pm ESTFree
This webinar will feature talks by two figures in astronomy research.
First, Dr. Steve Howell (NASA) will present "Using AAVSO photometry to understand and characterize variable giant stars." During a multi-year campaign, the AAVSO provided multi-color photometry to complement optical spectroscopy in an attempt to understand a number of long-standing misunderstood complexities and characteristics in a set of variable giant and supergiant stars. Dr. Howell will review the observations and how they have been fit together to formulate new insights into such stars, and will highlight a few particularly interesting examples.
Second, Dr. Juan Echevarría (UNAM) will discuss "Spectroscopic and photometric observations of the intermediate polar DW Cnc." He will present spectroscopy and photometric observations of the DW Cnc interactive binary during a low state and the beginning of a return to a high state: we will see that the signal from the spin of the white dwarf (38 min.), as well as the beat period signal (69 min.), were both absent, and mostly the power spectra showed the orbital period frequency (86 min). On the way to the high state, we will start to see the former signals, but they are still not of the strength of the observations made around 1999-2003 by Patterson et al. (2004) and Rodriguez-Gil et al. (2004).