NCSA staff who would like to submit an item for the calendar can email newsdesk@ncsa.illinois.edu.
Speaker: Yujie WanDate/Time: March 7, 2025 / 12 noon central.Location: NCSA 1040Zoom: https://illinois.zoom.us/j/82318062756?pwd=M3g1MFF6cytsOWFEbmU0UW1XWVoxQT09Title: Millimeter-wave transient detection in the Galactic plane with SPT-3GAbstract: Recent cosmic microwave background (CMB) experiments have opened the millimeter-wave (mm) regime of the electromagnetic spectrum to time-domain astrophysics. While mm observations have been conducted in the past, this is the first time that transient events have been blindly discovered in non-targeted surveys, as opposed to follow-up or pointed observations. Past mm-wave transient surveys with the South Pole Telescope (SPT) targeted the extragalactic sky and have detected hundreds of transient events, with most of them being galactic flaring stars. In this talk, we will present the first mm-wave time-domain survey towards the Galactic plane with SPT-3G (the third generation SPT camera). This survey consists of approximately 500 observations covering 100 square degrees of the Galactic plane in both 2023 and 2024, with plans for more observations in the coming years. The survey measures intensity and linear polarization in three bands centered at 95, 150 and 220 GHz. Until now, we have detected two transient events above a threshold of 5𝜎 in both 95 and 150GHz bands. Both events are associated with previous known binary systems with white dwarf accretors. Future analysis will involve lowering the detection threshold and improving the transient pipeline to be sensitive to timescales of minutes.