US NGO at the AAS #241 Meeting

2023 AAS Splinter Session: The Role of Gemini Observations in the Era of JWST

Wednesday, January 11, 2023, 9:00 AM - 10:30 AM. Seattle Convention Center in Room 204

SOC: Letizia Stanghellini (Chair, NSF's NOIRLab/CSDC), Vinicius Placco (NSF's NOIRLab/CSDC), Janice Lee (NSF's NOIRLab/Gemini)

The US National Gemini Office, at the Community Science and Data Center/NSF's NOIRLab, will host a Splinter Session at the 241st AAS Meeting in Seattle. The meeting is part of a planned series where scientists show their results based on Gemini observations, focusing on a particular topic. The main topic for the Splinter Session is the importance of Gemini observations in the JWST era. For the scientific program, we focus on science enhanced by the synergy between Gemini and JWST data, for example, to encourage the usage of Gemini data to plan and enrich the results from Webb. The speakers are not exclusively PI/co-Is of JWST-approved programs, instead, scientists planning or already working on data from both (and possibly other) observatories to increase their science scope.

The Splinter Session is open to all interested. During its 90-minute duration, it will have a short introduction, five science talks (listed below), and time for general discussion at the end. Invited speakers are current and potential Gemini users who have shown an interest in combining their Gemini data with JWST observations. We included science topics that cover several of the main Webb themes, such as planets and exoplanets, stellar populations and the ISM, galaxies, high-energy astrophysics, and cosmology.

Jillian Rastinejad (CIERA Northwestern) - Building on the Neutron Star Merger Counterpart Diversity Revealed by Gemini Observatory with JWST

Click here for the presentation slides (PDF)

Combined, Gemini's rapid ToO capabilities, wide coverage of the Northern and Southern sky, sensitivity, and diverse instrument suite render it a premier observatory for ground-based transient follow-up. In this talk, I will discuss Gemini's vital role in uncovering the optical-near-IR counterparts of short gamma-ray bursts (SGRBs), known to result from neutron star (NS) mergers. Specifically, Gemini has discovered tens of faint SGRB afterglows and has provided unique insight into the diversity of kilonovae: short-lived, enigmatic transients that are the sole observed site of r-process (heavy element) nucleosynthesis in the Universe. First, I will present our comprehensive catalog of optical-near-IR observations of 85 short GRBs which reveals the diversity of kilonovae uniformly observed at a pole-on angle. Against this backdrop, I will present our surprising discovery of a kilonova following a long GRB (duration ~ 50s) at 350 Mpc using Gemini. Finally, I will discuss how Gemini's rapid follow-up of future NS mergers will complement deep JWST observations, likely only available on ~week-long timescales, maximizing the scientific output of kilonovae discovered following GRBs and gravitational wave events.

Ryan Lau (NSF's NOIRLab) - Revealing and Resolving Dusty Stellar Outbursts with Gemini and JWST

Click here for the presentation slides (PDF)

Dust grains are the seeds of star and planet formation and are direct tracers of the chemical enrichment of the Universe. Despite the importance of dust in tracing our own cosmic origins, the origins of dust are unclear. Driven by the resurgence of optical and infrared (IR) time-domain surveys, emerging classes of IR-luminous stellar transient events have been identified and present potential sites of substantial dust formation. However, their role as dust and chemical factories has been largely unexplored due to observational limitations on discovering and characterizing such dust-obscured outbursts. This situation is now dramatically changing with the launch of JWST and the upcoming Legacy Survey of Space and Time (LSST) with the Vera C. Rubin Observatory. The sheer number of IR transient candidates to be discovered by Rubin will likely overwhelm the follow-up capabilities of JWST, which highlights the crucial role of the Gemini Observatory’s rapid response capabilities and (AO-assisted) IR instrumentation. In this talk, I will present early results from JWST Early Release Science (ERS) and Guaranteed Time Observations (GTO) programs ERS 1349 (PI - R. Lau) and GTO 1240 (PI - M. Ressler) on dusty stellar outbursts that demonstrate Gemini’s role in tracing the explosive origins of dust from the emerging classes of IR-luminous stellar transients.

Alexandra Tetarenko (Texas Tech University) - Probing the dynamic environment near stellar-mass black holes with Gemini and JWST

Click here for the presentation slides (PDF)

Black hole X-ray binaries are accreting objects that launch powerful relativistic jets. These binary systems evolve through bright outburst phases on rapid timescales of days to months, allowing us to probe jet/accretion phenomena in real-time. As X-ray binaries produce highly variable emission, time-domain observations can be a powerful tool to study these systems. However, as X-ray binaries emit across the electromagnetic spectrum, with the in-flowing matter dominating shorter wavelengths and the outflowing jet dominating longer wavelengths, we need a suite of fast-timing capable facilities to take full advantage of time-domain techniques. Gemini's `Alopeke/Zorro instruments are capable of providing rapid sampling (tens of ms) of X-ray binary emission in two simultaneous bands, and in turn, provide an exciting new option for characterizing X-ray binary variability in the optical regime. In this talk, I will present the first results on X-ray binaries observed with Gemini's 'Alopeke/Zorro, and I will discuss how synchronized Gemini and JWST observations can increase our understanding of jet physics, particle acceleration, and the rapidly changing plasma conditions near these black holes.

Adam McKay (Appalachian State University) - Gemini Observations of Active Centaurs Observed by JWST NIRSPEC

Click here for the presentation slides (PDF)

Centaurs are primitive, ice-rich solar system bodies with orbits between Jupiter and Neptune and are thought to be objects migrating inward from the Kuiper Belt to the Jupiter Family Comet population. Some centaurs are observed to exhibit comet-like activity in the form of dust comae and tails, but detections of the molecular ices whose sublimation is responsible for the observed cometary activity is relatively rare. Therefore, our knowledge of centaur volatile composition and activity drivers is limited. In cycle 1, JWST NIRSPEC will observe six active centaurs, including 29P/Schwassmann-Wachmann 1 (GO Program 2416, PI McKay). These observations will characterize the H2O, CO2, and CO abundances in the comae of these active centaurs, as well as whether any water ice grains are present. Gemini is supporting these JWST observations in several ways: 1) Recovery and orbital refinement for these centaurs to ensure accurate ephemerides so that JWST observations are successful, 2) Characterizing their activity state and other properties through imaging, and 3) A GRACES program to obtain high spectral resolution optical spectroscopy of 29P contemporaneous with the JWST observations in an effort to better understand OI photochemistry in cometary (and centaur) comae. We will discuss how Gemini is supporting JWST observations of active centaurs and how joint observations with Gemini and JWST enhance the science return from both facilities.

Daichi Hiramatsu (CfA Harvard-Smithsonian) - Gemini-JWST Synergies for Revealing Progenitors and Mechanisms of Cosmic Explosions

Click here for the presentation slides (PDF)

Transient astronomy is in bloom with ongoing wide-field surveys, which will be further enhanced by the upcoming Legacy Survey of Space and Time and LIGO-Virgo-KAGRA Observing Run 4. The Gemini Observatory is well situated in this science thanks to its large aperture, all-sky coverage, optical/near-infrared sensitivity, and queue observing system. This is essential for the early characterization of cosmic explosions (e.g., light-curve and spectral evolution of supernovae and kilonovae). The vetted targets can be followed up by the James Webb Space Telescope (JWST) for the latest phase ever in mid-infrared, where important nucleosynthesis signatures (e.g., r-process elements) should be present. In this talk, I will present how we reveal progenitors and explosion mechanisms of supernovae and kilonovae with the Gemini-JWST synergies.