BEGIN:VCALENDAR VERSION:2.0 PRODID:-//CERN//INDICO//EN BEGIN:VEVENT SUMMARY:From Starlight to Synapses: How Cosmological Bayesian Inference Re veals the Brain's Molecular Structure DTSTART;VALUE=DATE-TIME:20261028T182100Z DTEND;VALUE=DATE-TIME:20261028T182200Z DTSTAMP;VALUE=DATE-TIME:20261023T010746Z UID:indico-contribution-53-3671@nyx.physics.mcgill.ca DESCRIPTION:Speakers: Manveer Sidhu (Ontario Tech University\, Dunlap Inst itute for Astronomy and Astrophysics)\nSuper-resolution microscopy is a ra pidly evolving field\, and analytical tools are struggling to keep up with novel imaging techniques. 'MINFLUX' (minimal fluorescence photon fluxes) is one such technique\; it uses targeted emission to track molecules down to the nanometer scale. However\, 'MINFLUX' outputs localizations of these molecules rather than viewing the protein superstructure directly\, leavi ng a gap for a tool that can make that leap. 'AstroPhot' is a Bayesian fra mework traditionally used to analyze and deblend crowded/transient cosmolo gical data by separating objects and fitting parameters individually. With some unifying adjustments\, 'AstroPhot' can be calibrated to ingest MINFL UX data and fit shared parameters across objects to fit greater protein su perstructure based on molecular localizations. This approach is tested aga inst 'MINFLUX' data from neural inhibitory synapses\, where the hexagonal lattice structure of the gephyrin protein is analyzed. Gephyrin is crucial in the regular function of the brain\; mutations and abnormalities in gep hyrin are linked to epilepsy\, Alzheimer's\, and schizophrenia. The natura l superstructure formed by gephyrin in the brain is debated throughout the literature. Thus\, understanding gephyrin structure and applying the appr oach used to other proteins is key to tackling some of the longstanding ne urological disorders plaguing humanity.\n\nhttps://nyx.physics.mcgill.ca/e vent/587/contributions/3671/ LOCATION:Online URL:https://nyx.physics.mcgill.ca/event/587/contributions/3671/ END:VEVENT BEGIN:VEVENT SUMMARY:Unveiling the Origins of a Historic Supernova DTSTART;VALUE=DATE-TIME:20261028T182000Z DTEND;VALUE=DATE-TIME:20261028T182100Z DTSTAMP;VALUE=DATE-TIME:20261023T010746Z UID:indico-contribution-53-3691@nyx.physics.mcgill.ca DESCRIPTION:Speakers: Amilia Petryk (University of Manitoba)\nThe nature o f historical supernovae is often unknown\, but supernova remnants and thei r environments can serve as powerful tools for probing the progenitor syst em. RCW 86 is a peculiar supernova remnant\, thought to be associated with the historical supernova SN 185. A prevailing theory is that it was a cav ity explosion\, leading to questions about the nature of the progenitor sy stem. To better characterize this supernova remnant\, long-slit spectrosco pic data of RCW 86’s expanding shock front were gathered in 2025 using t he 8.1-meter Gemini South telescope. The data were reduced via the Gemini DRAGONS pipeline\, with the goal of measuring the ionized hydrogen and hel ium fluxes and converting them into surface brightnesses. CLOUDY (1D photo ionization simulation software) models were run for two different models: a blackbody model and a stripped-envelope model. The blackbody model repre sents thermonuclear runaway supernovae\, as a white dwarf accretes matter from a companion star\, whereas the stripped-envelope star model represent s core-collapse supernovae. The surface brightnesses of these models were compared with the observed surface brightnesses\, and the models were cons trained accordingly. The temperature and luminosity of the blackbody sourc es were constrained to models with high temperatures and low luminosities. The mass and luminosity of the stripped-envelope star model was constrain ed to ~4 M$\\odot$ and ~2.5 L$\\odot$\, respectively. With this work we ha ve placed novel constraints on the progenitor of RCW 86.\n\nhttps://nyx.ph ysics.mcgill.ca/event/587/contributions/3691/ LOCATION:Online URL:https://nyx.physics.mcgill.ca/event/587/contributions/3691/ END:VEVENT BEGIN:VEVENT SUMMARY:The Impact of Inspiral Timing and Model Assumptions on Convective Common Envelopes DTSTART;VALUE=DATE-TIME:20261028T181900Z DTEND;VALUE=DATE-TIME:20261028T182000Z DTSTAMP;VALUE=DATE-TIME:20261023T010746Z UID:indico-contribution-53-3697@nyx.physics.mcgill.ca DESCRIPTION:Speakers: Chaudhuri Aishani (University of Toronto)\nCommon en velope (CE) evolution occurs when one\, often more massive\, star in a bin ary system completely engulfs a nearby companion. The companion continues its inspiral inside the shared envelope\, leading to one of two outcomes: the companion merges with the primary star\, or its liberated orbital ener gy unbinds and ejects the envelope. In the latter case\, the ejection of t he envelope leaves behind a tight binary\; this process is thought to be t he primary formation mechanism for both thermonuclear supernova and gravit ational wave progenitor systems. However\, population synthesis codes ofte n fail at reproducing the observed population of these systems\, highlight ing gaps in our physical understanding of the CE phase. In this work\, we study the physics of CE evolution by using a convective CE model\, which accounts for the redistribution of energy by convection within the primary \, where inspiral energy liberated in a convection-dominated zone is lost via convection and radiation. We extend previous research by investigating how the specific convection models assumptions adopted in the stellar evo lution code MESA impact the predictions for the outcome of CE evolution al ong the asymptotic giant branch (AGB). We find that differences in stellar structure caused by variations in the adopted convective parameters can l ead to drastic differences in the predicted CE efficiency (and therefore f inal binary separation)\, particularly for binaries with large initial sep arations which enter the CE towards the end of the primary’s AGB phase.\ n\nhttps://nyx.physics.mcgill.ca/event/587/contributions/3697/ LOCATION:Online URL:https://nyx.physics.mcgill.ca/event/587/contributions/3697/ END:VEVENT BEGIN:VEVENT SUMMARY:Extragalactic Probes for a Galactic Model: Validating the NE2025 G alactic Electron Density Model using CHIME Fast Radio Bursts Scattering Me asurements DTSTART;VALUE=DATE-TIME:20261028T181800Z DTEND;VALUE=DATE-TIME:20261028T181900Z DTSTAMP;VALUE=DATE-TIME:20261023T010746Z UID:indico-contribution-53-3678@nyx.physics.mcgill.ca DESCRIPTION:Speakers: Daniel Amouyal (McGill University)\nModels of the Ga lactic electron density are widely used to predict distances and scatterin g of compact radio sources\, and to account for interstellar medium foregr ounds in extragalactic studies. The recently updated NE2025 model (Ocker & Cordes 2026) offers improvements over its predecessor\, the commonly refe renced NE2001. However\, its scattering predictions have yet to be tested by extra-galactic sources. In this talk\, I will present a direct test usi ng fast radio bursts (FRBs) detected by CHIME/FRB. Since FRB signals propa gate through the full Galactic interstellar medium\, their observed scatte ring must equal or exceed the Milky Way contribution\, making them natural constraints on Galactic scattering models. Using CHIME/FRB baseband data\ , we measure scattering timescales at microsecond-to-millisecond precision and compare them to the NE2025 prediction along each line of sight. I wil l show that while most FRBs are scattered well beyond the Galactic predict ion\, a subset of minimally scattered FRBs place hard upper limits on the true Galactic scattering\, clustering in a region of overestimation by NE2 025 . I will discuss what these sightlines can reveal regarding specific m odel parameters\, and the outlook for using FRBs to calibrate future model s.\n\nhttps://nyx.physics.mcgill.ca/event/587/contributions/3678/ LOCATION:Online URL:https://nyx.physics.mcgill.ca/event/587/contributions/3678/ END:VEVENT BEGIN:VEVENT SUMMARY:Quantifying the Effect of a Bottom-Light IMF on Globular Cluster E volution Using the Cluster Monte Carlo Code DTSTART;VALUE=DATE-TIME:20261028T181700Z DTEND;VALUE=DATE-TIME:20261028T181800Z DTSTAMP;VALUE=DATE-TIME:20261023T010746Z UID:indico-contribution-53-3682@nyx.physics.mcgill.ca DESCRIPTION:Speakers: Kristen Cowan (Saint Mary's University)\nThe distrib ution of stellar masses within a globular cluster (GC) at the time of form ation\, referred to as the Initial Mass Function (IMF)\, is directly linke d to the evolution of the cluster\, including the rate of binary black hol e (BH) mergers that produce gravitational waves. Recent studies suggest th at GCs may have formed with a bottom-light IMF\, meaning fewer low mass st ars and more BH progenitors per unit cluster mass compared to the standard Kroupa (2001) IMF. In this study\, we evolve a small set of simulated GCs with a bottom-light IMF using the Cluster Monte Carlo code\, which models the dynamical interactions between stars\, the formation and retention of compact objects and the large-scale evolution of the cluster mass and rad ius. We then compare the evolutionary data to an identical set of clusters formed with the standard Kroupa IMF to quantify the effect of the varying mass distribution. By analysing properties including black hole populatio ns\, cluster mass and radius over time\, we investigate whether a bottom-l ight IMF produces properties of evolved GCs that differ significantly from those produced by a Kroupa IMF. The results of these simulations can be c ompared to current photometric observations to inform future work surround ing the IMF and help revise predictions for the rates of binary BH mergers originating in GCs.\n\nhttps://nyx.physics.mcgill.ca/event/587/contributi ons/3682/ LOCATION:Online URL:https://nyx.physics.mcgill.ca/event/587/contributions/3682/ END:VEVENT BEGIN:VEVENT SUMMARY:From Starless Cores to Embedded Disks: Chemistry and Fragmentation in Early Star Formation DTSTART;VALUE=DATE-TIME:20261028T181600Z DTEND;VALUE=DATE-TIME:20261028T181700Z DTSTAMP;VALUE=DATE-TIME:20261023T010746Z UID:indico-contribution-53-3683@nyx.physics.mcgill.ca DESCRIPTION:Speakers: Rajeeb Sharma (Herzberg Astronomy and Astrophysics)\ nThe physical and chemical conditions present during planet formation are established during the earliest embedded Class 0/I phases of star formatio n. At this stage\, protostellar systems are still being shaped by infall\, outflows\, irradiation\, and chemical processing. Understanding how these processes set the initial conditions for star and planet formation requir es observations that can resolve the small-scale structures within embedde d systems. We present the first systematic high-angular resolution (0.1” \, ~15 au) study of disk-scale chemistry in 19 nearby embedded protostars as part of the ALMA Large Program eDisk. Using multiple molecular tracers\ , we identify the distinct morphologies within these young systems. $^{12} $CO and SiO trace outflows and jets\, while $^{13}$CO and C$^{18}$O trace rotating inner envelope and disk regions. The compact hot core regions are traced by DCN and CH$_{3}$OH\, and are particularly prominent towards the youngest Class 0 sources. Hydrocarbons are associated with UV-irradiated outflow cavity walls\, while SO and H$_{2}$CO show complex morphology\, tr acing various structures that include non-axisymmetric infall through stre amers. Recently\, we are using archival ALMA observations to investigate f ragmentation in dense starless cores. This complementary study probes the structures that precede protostellar formation and will help connect the i nitial fragmentation of dense cores with the physical and chemical complex ity observed in young embedded systems. Together\, these efforts will prov ide a more complete view of the initial conditions of star and planet form ation.\n\nhttps://nyx.physics.mcgill.ca/event/587/contributions/3683/ LOCATION:Online URL:https://nyx.physics.mcgill.ca/event/587/contributions/3683/ END:VEVENT BEGIN:VEVENT SUMMARY:Fifteen Years of Archival ALMA Data as a Survey: A Search for Accr etion Streamers in Serpens Main DTSTART;VALUE=DATE-TIME:20261028T181500Z DTEND;VALUE=DATE-TIME:20261028T181600Z DTSTAMP;VALUE=DATE-TIME:20261023T010746Z UID:indico-contribution-53-3711@nyx.physics.mcgill.ca DESCRIPTION:Speakers: Samuel Fielder (University of Victoria)\nProtostella r accretion streamers are coherent filamentary structures that channel mat erial from envelope scales and beyond into protostellar cores. Largely fou nd serendipitously\, streamers have emerged as a potentially important yet poorly characterized mode of mass assembly in early star formation\, with occurrence rates\, class dependence\, and environmental dependence still unconstrained. ALMA-SAILS (ALMA Search for Asymmetry and Infall at Large S cales) addresses this by treating nearly 15 years of the ALMA Science Arch ive as a survey. Data taken for other science goals are uniformly reproces sed on CANFAR into a single\, self-consistent dataset at no additional obs erving cost. Our pilot study targets Serpens Main\, combining 96 datasets from 43 ALMA projects (Bands 3–8\, Cycles 2–11). Uniform self-calibrat ion and imaging yields ~200 continuum images across 59 targets. Emission i s detected toward 43 of them. About 20 (47%) show extended or asymmetric s tructure rather than a compact core\, and ~10 exhibit extended features ≥2000 au\, which suggests infall from beyond the dense core. Cross-match ing with protostellar catalogs lets us compare candidate fractions across evolutionary stages. Since continuum morphology cannot confirm infall\, we also run automated line identification across 881 line-bearing spectral w indows. We confirm 112 detections of dense-gas and infall tracers toward 2 4 sources. We present our first kinematic results toward the strongest can didates\, using SCOUSE and ACORNS to isolate coherent velocity structures\ , while noting a key limit of archival data: over a third of spectral wind ows are too coarse (>5 km/s) to resolve streamer velocity gradients.\n\nht tps://nyx.physics.mcgill.ca/event/587/contributions/3711/ LOCATION:Online URL:https://nyx.physics.mcgill.ca/event/587/contributions/3711/ END:VEVENT BEGIN:VEVENT SUMMARY:Search for 21-cm absorption systems with CHIME DTSTART;VALUE=DATE-TIME:20261028T180500Z DTEND;VALUE=DATE-TIME:20261028T181500Z DTSTAMP;VALUE=DATE-TIME:20261023T010746Z UID:indico-contribution-53-3668@nyx.physics.mcgill.ca DESCRIPTION:Speakers: Arash Mirhosseini (Dunlap Institute for Astronomy & Astrophysics\, University of Toronto)\nNeutral atomic hydrogen is the prim ary raw material from which stars form in galaxies\; and understanding its spatial distribution\, kinematics\, and thermal state across cosmic time is therefore fundamental to our comprehension of how galaxies assemble and evolve. The 21-cm hyperfine transition of neutral hydrogen is a powerful probe of cold gas in and around galaxies across cosmic time. When a radio source lies behind a cloud of neutral hydrogen\, the cold gas imprints a c haracteristic absorption feature in the spectrum of the background source at the redshifted 21-cm frequency. Unlike 21-cm emission\, the absorption feature is detectable independently of the distance to the absorber\, so i ts detectability does not diminish with redshift. Despite this advantage\, the known sample of extragalactic 21-cm absorbers at redshifts z > 1 has remained small: only 42 systems were known prior to this work\, reflecting the scarcity of suitable radio facilities at the relevant frequencies.\n\ nIn this talk\, I present the results of a pilot blind search for 21-cm ab sorption systems conducted with the Canadian Hydrogen Intensity Mapping Ex periment (CHIME)\, a radio telescope operating between 400 and 800 MHz\, w hich corresponds to the 21-cm line at redshifts 0.78 < z < 2.55. This pilo t survey resulted in the discovery of a new 21-cm absorber at z = 2.327\, which is only the fifth known absorber associated with a quasar at z > 2. The survey also recovered two previously known intervening absorbers\, val idating the detection pipeline.\n\nhttps://nyx.physics.mcgill.ca/event/587 /contributions/3668/ LOCATION:Online URL:https://nyx.physics.mcgill.ca/event/587/contributions/3668/ END:VEVENT BEGIN:VEVENT SUMMARY:Bridging the Gap in the New Era of Star Formation DTSTART;VALUE=DATE-TIME:20261028T175500Z DTEND;VALUE=DATE-TIME:20261028T180500Z DTSTAMP;VALUE=DATE-TIME:20261023T010746Z UID:indico-contribution-53-3633@nyx.physics.mcgill.ca DESCRIPTION:Speakers: Jaiden Peltonen (University of Alberta)\nWith the ad vent of JWST imaging in the Local Group\, young stellar objects (YSOs) are being observed in a broader range of environments than ever before\, whic h will revolutionize our understanding of star formation if their properti es can be modelled accurately. We present a new approach to characterizing YSO populations by applying the technique of population synthesis origina lly developed for older stellar populations (Peltonen et al. 2026). Using the latest YSO radiation transfer and stellar evolution models\, we have d eveloped a population synthesis code that can generate YSO populations\, a ccounting for details like binaries\, clustering\, extinction\, and stocha stic sampling. We used this new code to determine the properties of YSOs i n the recent JWST images of NGC 604 within M33 and previous Spitzer studie s of the LMC. This approach allows us to measure the star formation rate i n extragalactic systems directly from YSOs instead of relying on tracers f rom massive stars (Halpha\, photospheric emission). With this powerful tec hnique\, we can also turn to local clouds in the Spitzer Extended Solar Ne ighborhood Archive (SESNA). We present preliminary results to constrain th e star formation histories in the SESNA molecular clouds. Ultimately\, thi s population synthesis framework will allow us to evaluate the current sta r formation properties in any region with an observed YSO population and a llow us to directly connect the Milky Way star formation properties to tho se of extragalactic systems.\n\nhttps://nyx.physics.mcgill.ca/event/587/co ntributions/3633/ LOCATION:Online URL:https://nyx.physics.mcgill.ca/event/587/contributions/3633/ END:VEVENT BEGIN:VEVENT SUMMARY:Visibility Plane Forward Modeling of Young Massive Clusters within the Nuclear Ring of NGC 3351 DTSTART;VALUE=DATE-TIME:20261028T174500Z DTEND;VALUE=DATE-TIME:20261028T175500Z DTSTAMP;VALUE=DATE-TIME:20261023T010746Z UID:indico-contribution-53-3650@nyx.physics.mcgill.ca DESCRIPTION:Speakers: Peter Knowlton (University of Victoria)\nUsing high- resolution ALMA millimeter observations\, we investigate the formation of massive star clusters within the nuclear ring in NGC 3351\, a nearby Milky Way analog galaxy. The dense\, high-pressure conditions within nuclear ri ngs are among the most extreme star-forming settings in the local universe \, providing the ideal conditions for massive cluster formation. Neverthel ess\, the mechanisms driving massive cluster formation and the impact of e nvironmental conditions remain poorly understood. They are distinct from l ower-mass clusters in that they form quickly and convert gas to stars effi ciently\, doing so before the significant onset of stellar feedback from n ewly formed stars. To study the full conditions of massive cluster formati on\, we must observe their short\, infant stages when they are actively st ar-forming and newborn stars remain deeply embedded in gas and dust. This phase is best traced by (sub-)millimeter observations. We perform our anal ysis directly in the raw visibility plane using the GALARIO package to con vert forward models of the region into model visibilities sampled at the s ame baselines as our observations. This approach avoids image-plane-based reconstruction methods that produce artifacts and correlated noise\, and i t preserves the full data resolution\, allowing us to better constrain the intrinsic radial profiles of the young massive clusters and the physics o f their star formation. Furthermore\, we can derive higher-fidelity estima tes and uncertainties of the shared morphology of the ring and clusters\, contributing to our understanding of how gas accretion onto the nuclear ri ng drives massive cluster formation along its structure.\n\nhttps://nyx.ph ysics.mcgill.ca/event/587/contributions/3650/ LOCATION:Online URL:https://nyx.physics.mcgill.ca/event/587/contributions/3650/ END:VEVENT BEGIN:VEVENT SUMMARY:Leveraging CANFAR and the ALMA archive to create SALVAGE - II: the effect of AGN feedback on central molecular gas DTSTART;VALUE=DATE-TIME:20261028T173500Z DTEND;VALUE=DATE-TIME:20261028T174500Z DTSTAMP;VALUE=DATE-TIME:20261023T010746Z UID:indico-contribution-53-3655@nyx.physics.mcgill.ca DESCRIPTION:Speakers: Scott Wilkinson (Queen's University)\nUnderstanding the mechanisms that drive and halt star formation requires an assessment o f both the stellar and gaseous components of a large statistical sampling of galaxies. For Canadian astronomers\, large optical surveys have adequa tely serviced the stellar components\, but large samples of resolved molec ular gas observations are challenging to acquire. However after 13+ years of operations\, the ALMA Science Archive has accumulated an untapped wealt h of molecular gas observations waiting to be analyzed as an ensemble. Ena bled by the CANFAR Science Platform\, the SDSS-ALMA Legacy-Value Archival Gas Exploration (SALVAGE) dataset encompasses ~300 galaxies with optical d ata from the Sloan Digital Sky Survey (SDSS) and CO(1-0) maps from ALMA. T ogether\, these products allow for a “semi-resolved” perspective of t he gas and stars\, meaning that the inner ~2kpc (set by the SDSS spectrosc opic fibre diameter) and outer regions can be independently studied. \n\nI n this presentation\, I will use SALVAGE to quantify how feedback from an active galactic nucleus (AGN) affects the molecular gas. Although simulati ons show that AGN feedback can remove gas from galaxies\, nearly all obser vational studies of low-redshift AGN show no evidence of gas depletion. Re cent works have found that **AGN can only remove gas from the central regi ons**\, but are limited to small samples. SALVAGE allows us to test this r esult with substantially larger statistics. Using a sample of 70 AGN and m atched non-AGN controls\, I will assess whether AGN hosts show evidence fo r reduced central molecular gas\, providing observational constraints on t he role of AGN in galaxy evolution.\n\nhttps://nyx.physics.mcgill.ca/event /587/contributions/3655/ LOCATION:Online URL:https://nyx.physics.mcgill.ca/event/587/contributions/3655/ END:VEVENT BEGIN:VEVENT SUMMARY:Bridging the gap between Milky Way and extragalactic star formatio n studies DTSTART;VALUE=DATE-TIME:20261028T172500Z DTEND;VALUE=DATE-TIME:20261028T173500Z DTSTAMP;VALUE=DATE-TIME:20261023T010746Z UID:indico-contribution-53-3651@nyx.physics.mcgill.ca DESCRIPTION:Speakers: Hannah Christie (University of Alberta)\nMeasurement s of massive star formation from Galactic and extragalactic cloud-scale ob servations produce conflicting results. Theory predicts that gas surface d ensity\, velocity dispersion\, virial parameter\, and gravitational freefa ll time should play a key role in setting the timescale for star formation . Milky Way observations support this prediction. In extragalactic systems \, observations find weak\, or even anti-correlations\, with predictions f rom theory. There remains\, however\, a significant gap between the scales probed in extragalactic surveys (50-150pc) and the resolved cloud observa tions from Milky Way studies (~10pc) which could account for this tension. This work addresses the spatial gap between these studies using new ALMA 12CO(2–1) and 12CO(1-0) observations of M33. The resolution of these dat a (~10pc) matches the spatial scales resolved in Milky Way studies allowin g for direct comparisons to be made. We measure star formation rates usin g the early embedded phase of massive star formation\, enabled by JWST obs ervations. Using these data\, we find no strong correlation between the st ar formation efficiency and molecular gas properties in resolved extragala ctic molecular clouds. Our results find that the tension between Milky Way and extragalactic observations cannot be attributed to a gap in spatial s cales. Future work will extend our study of resolved cloud observations to local volume galaxies across a range of galactic environments.\n\nhttps:/ /nyx.physics.mcgill.ca/event/587/contributions/3651/ LOCATION:Online URL:https://nyx.physics.mcgill.ca/event/587/contributions/3651/ END:VEVENT BEGIN:VEVENT SUMMARY:Identifying Candidates of Partially Stripped Yellow Supergiants DTSTART;VALUE=DATE-TIME:20261028T171500Z DTEND;VALUE=DATE-TIME:20261028T172500Z DTSTAMP;VALUE=DATE-TIME:20261023T010746Z UID:indico-contribution-53-3639@nyx.physics.mcgill.ca DESCRIPTION:Speakers: Shannon Bowes (University of Toronto)\nDespite the t raditional model of a Yellow Supergiant as a brief transitional phase in a star’s life before the onset of core helium burning\, there is an incre asing catalog of supernovae explosions that have had their progenitors ide ntified as Yellow Supergiants from pre-explosion imaging. Notably\, these supernovae are both partially-stripped and hydrogen-poor. The widespread i nterpretation for these observations is that a binary companion partially strips the supernova progenitor of its stellar envelope\, after which it s ubsequently explodes as a Yellow Supergiant\, having the appropriate tempe ratures and luminosities for this regime. Still\, no analogs to these part ially-stripped Yellow Supergiants have been discovered in Local Group gala xies that can be studied in detail prior to their explosion. Theoretical m odels predict that certain pulsations should be excited exclusively in par tially stripped Yellow Supergiants\, resulting in unique lightcurve morpho logy. Therefore\, the variability of Yellow Supergiants can provide unique insight into their stellar structure and the presence of a full or partia lly-stripped hydrogen envelope. I will describe the ongoing program to cha racterize the variability of hundreds of YSGs in the Magellanic Clouds wit h the goal of finding potential partially-stripped Yellow Supergiants. In particular\, I will highlight the identification of candidate Yellow Super giants to date that have the predicted hallmarks of partially stripping\, and describe on-going follow-up efforts to confirm the nature of this sub- population.\n\nhttps://nyx.physics.mcgill.ca/event/587/contributions/3639/ LOCATION:Online URL:https://nyx.physics.mcgill.ca/event/587/contributions/3639/ END:VEVENT BEGIN:VEVENT SUMMARY:Searching for Carbon-Enhanced Metal-Poor Stars in DESI DTSTART;VALUE=DATE-TIME:20261028T170500Z DTEND;VALUE=DATE-TIME:20261028T171500Z DTSTAMP;VALUE=DATE-TIME:20261023T010746Z UID:indico-contribution-53-3641@nyx.physics.mcgill.ca DESCRIPTION:Speakers: Rosayla Coulthard (University of Toronto)\nCarbon-en hanced metal-poor (CEMP) stars are some of the oldest and most chemically primitive stars in the Milky Way. They are defined by excess carbon and lo w metallicity\, and further classified by neutron-capture enrichment. The origin of this unique enrichment varies between CEMP subclasses. Neutron-c apture-enriched CEMP stars reflect previous extrinsic enrichment events\, whereas CEMP stars with no neutron-capture enrichment (CEMP-no) are believ ed to be intrinsically enriched\, reflecting progenitor conditions. These varying enrichment histories provide key insights into nucleosynthetic pro cesses and the nature of the first stars. A challenge that remains for the ir study is the lack of large-scale\, homogeneous data. The scale problem may be addressed through major stellar surveys such as the Dark Energy Spe ctroscopic Instrument (DESI) Milky Way Survey Program. While DESI observes deeper into the Galactic halo and at lower magnitudes than other stellar surveys\, its resolution and signal-to-noise ratio make it difficult to cl assify CEMP stars using provided chemical abundances. Using DESI DR1 spect ra\, we constructed a method for flagging stars as CEMP using the CH-G ban d and the strontium line at 4077Å. This rough scheme separates CEMP-no st ars from remaining CEMP subclasses. It correctly classifies ≥80% of star s in common between DESI and high-resolution literature samples\, and ≥9 5% of stars in common between DESI and other surveys. We found a total of 3\,154 CEMP stars with a metallicity as low as -4.0 dex. High-resolution f ollow-up will be performed on the most viable candidates.\n\nhttps://nyx.p hysics.mcgill.ca/event/587/contributions/3641/ LOCATION:Online URL:https://nyx.physics.mcgill.ca/event/587/contributions/3641/ END:VEVENT BEGIN:VEVENT SUMMARY:Unlocking the evolution of star formation with CASTOR DTSTART;VALUE=DATE-TIME:20261028T165500Z DTEND;VALUE=DATE-TIME:20261028T170500Z DTSTAMP;VALUE=DATE-TIME:20261023T010746Z UID:indico-contribution-53-3658@nyx.physics.mcgill.ca DESCRIPTION:Speakers: Gareth Jones (University of Manitoba)\nUltraviolet o bservations provide a direct view of young stellar populations associated with recent star formation in galaxies\, complementing longer-wavelength o bservations that trace older stellar populations. The Canadian-led Cosmolo gical Advanced Survey Telescope for Optical and ultraviolet Research (CAST OR) will provide wide-field coverage with deep imaging fields\, enabling l arge samples of low-mass galaxies to be studied through recent star format ion. We investigate how addition of CASTOR observations affects recovery o f galaxy star formation rates (SFRs) from photometric spectral energy dist ribution (SED) fitting. We construct forward-modelled galaxy spectra using Binary Population and Spectral Synthesis models and galaxy populations dr awn from Santa Cruz semi-analytic model lightcones at `0\n\nhttps://nyx.ph ysics.mcgill.ca/event/587/contributions/3658/ LOCATION:Online URL:https://nyx.physics.mcgill.ca/event/587/contributions/3658/ END:VEVENT BEGIN:VEVENT SUMMARY:WEAVE-Pristine survey: NLTE-Informed Machine Learning for Stellar Parameters and Abundances in Pristine-selected metal-poor stars. DTSTART;VALUE=DATE-TIME:20261028T164500Z DTEND;VALUE=DATE-TIME:20261028T165500Z DTSTAMP;VALUE=DATE-TIME:20261023T010746Z UID:indico-contribution-53-3663@nyx.physics.mcgill.ca DESCRIPTION:Speakers: Minjih Kim (University of Victoria)\nHomogeneously a nalysing the chemical signatures of the Milky Way’s most pristine metal- poor stars is essential to reconstruct its early assembly and first-star n ucleosynthetic yields. Over the next few years\, WEAVE in the North and 4M OST in the South will enable high-resolution\, multi-object spectroscopic follow-up of millions of Gaia stars. We present a machine learning pipelin e for the WEAVE-Pristine survey to automate analysis of high-resolution (R ~ 20\,000) spectra of very ([Fe/H] < -2) to extremely ([Fe/H] < -3) metal -poor star candidates in the Pristine Data Release 2. The neural network i s trained on +100\,000 synthetic spectra interpolated from the MARCS atmos phere grid and varying 15 elements of which 9 of them were computed in Non -Local Thermal Equilibrium (NLTE) using the MPIA/1DNLTE spectral synthesis code. To reduce the synthetic gap\, we augment the spectra on-the-fly dur ing training with WEAVE instrumental effects. Thus\, we have an end-to-end pipeline that spans from the generation of raw synthetic spectra to the f inal prediction of stellar labels and their uncertainties\, including atmo spheric parameters (Teff\, log g\, [Fe/H]\, microturbulence) and individua l chemical abundances [X/Fe] for 15 species: alpha-elements (O\, Mg\, Si\, Ca\, Ti)\, iron-peak (Cr\, Mn\, Ni)\, light elements (Na\, Al)\, neutron- capture (Sr\, Ba\, Eu)\, and C/N. The pipeline is tested on both synthetic and observed spectra from early internal release of WEAVE observations\, including stars in the very metal poor globular cluster M15 and the solar metallicity open cluster NGC 6819.\n\nhttps://nyx.physics.mcgill.ca/event/ 587/contributions/3663/ LOCATION:Online URL:https://nyx.physics.mcgill.ca/event/587/contributions/3663/ END:VEVENT END:VCALENDAR