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Metallic-line A (Am) stars are main-sequence stars of around twice the massof the Sun that show element abundance peculiarities in their spectra. Theradiative levitation and diffusive settling processes responsible for theseabundance anomalies should also deplete helium from the region of the envelopethat drives delta Scuti pulsations. Therefore, these stars are not expected tobe delta Scuti stars, which pulsate in multiple radial and nonradial modes withperiods of around 2 hours. As part of the NASA TESS Guest Investigator Program,we proposed photometric observations in 2-minute cadence for samples of bright(visual magnitudes around 7-8) Am stars. Our 2020 SAS meeting paper reported onobservations of 21 stars, finding one delta Scuti star and two delta Scuti /gamma Doradus hybrid candidates, as well as many stars with photometricvariability possibly caused by rotation and starspots. Here we present anupdate including 34 additional stars observed up to February 2021, among themthree delta Scuti stars and two delta Scuti / gamma Doradus hybrid candidates.Confirming the pulsations in these stars requires further data analysis andfollow-up observations, because of possible background stars or contaminationin the TESS CCD pixels with scale 21 arc sec per pixel. Asteroseismic modelingof these stars will be important to understand the reasons for theirpulsations.

Characterizing Variability in Bright Metallic-Line A (Am) Stars Using Data from the NASA TESS Spacecraft