BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//CERN//INDICO//EN
BEGIN:VEVENT
SUMMARY:First Mid-Infrared Characterization of the Galactic Center WR Star
  Population
DTSTART;VALUE=DATE-TIME:20261028T182000Z
DTEND;VALUE=DATE-TIME:20261028T182100Z
DTSTAMP;VALUE=DATE-TIME:20261025T174722Z
UID:indico-contribution-3676@nyx.physics.mcgill.ca
DESCRIPTION:Speakers: Zachary Ireland (University of Toronto)\nThis resear
 ch presents the first mid-infrared characterization of the Galactic Center
  (GC) Wolf-Rayet (WR) and Ofpe/WN9 star population using integral-field sp
 ectroscopy from the JWST Mid-Infrared Instrument MRS. Data consist of cali
 brated\, three-dimensional FITS spectral cubes spanning λ∈[4.9\, 27.9] 
 μm at resolving power R∈[1330\, 3750]. As an initial application\, the 
 spectrum of the Ofpe/WN9 star IRS 16NW is analyzed in Channel 1\, being co
 rrected for extinction\, foreground H₂O rovibrational absorption\, defec
 ts\, and back/foreground emission. Spectral features are identified and de
 blended with multi-component Gaussian or quartic fits\, then assessed for 
 association with IRS 16NW using measurements of its line-of-sight velocity
  and expected line width. \n\nWR and Ofpe/WN9 stars undergo radiatively dr
 iven mass loss through stellar winds. Expelled material from approximately
  30 WR or Ofpe/WN9 stars is consistent with supplying all material availab
 le for accretion onto Sgr A*\; wind metallicity can therefore have implica
 tions for the accretion rate: higher metal abundances enhance radiative co
 oling\, allowing shocked winds to lose thermal pressure support and reach 
 smaller radii. By identifying the intrinsic mid-IR spectral contributions 
 of these stars and separating them from surrounding GC structures\, the an
 alysis further constrains the composition/metallicity of the accretion env
 ironment of Sgr A*. Metal-line ratios are derived either directly from det
 ected stellar emission or\, for non-detections\, constrained using Monte C
 arlo injection-recovery tests.\n\nhttps://nyx.physics.mcgill.ca/event/587/
 contributions/3676/
LOCATION:Online 
URL:https://nyx.physics.mcgill.ca/event/587/contributions/3676/
END:VEVENT
END:VCALENDAR