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As part of the High order Advanced Keck Adaptive optics (HAKA) project, a state-of-the-art ALPAO 2844 actuator deformable mirror (DM) will replace the more than 25 years old 349 actuator DM on the Keck Adaptive Optics (AO) bench. The increase in the number of DM actuators requires a new set of pupil-relay optics (PRO) to map the 2.5mm DM actuator spacing to the 200μm lenslet spacing on the Shack-Hartmann wavefront sensor (WFS). A new lenslet array with increased focal lengths will be procured in order to maintain current plate scales. HAKA will initially support science with the near-infrared camera (NIRC2), a single mode fiber fed spectrograph (KPIC + NIRSPEC) and a fast visible imager (ORKID). In addition, a new infrared wavefront sensor (`IWA) is being designed to support science with ORKID and a suite of new science instruments: a mid-infrared coronagraphic integral field spectrograph (SCALES) and a fiber-fed high-resolution spectrograph (HISPEC). We present the opto-mechanical design of the HAKA DM, Shack-Hartmann WFS upgrades and the `IWA system. A mount for the HAKA DM will allow for quick integration and alignment to the Keck AO bench. The upgrade to the WFS PRO includes a new set of optics and associated mounting that fits within the mechanical constraints of the existing WFS and meets the requirements of the HAKA DM. 

Abstract Young, self-luminous super-Jovian companions discovered by direct imaging provide a challenging test for planet formation and evolution theories. By spectroscopically characterizing the atmospheric compositions of these super-Jupiters, we can constrain their formation histories. Here we present studies of the recently discovered HIP 99770 b, a 16M_Juphigh-contrast companion on a 17 au orbit, using the fiber-fed high-resolution spectrograph KPIC ( $\mathcal{R}$∼ 35,000) on the Keck II telescope. OurK-band observations led to detections of H₂O and CO in the atmosphere of HIP 99770 b. We carried out free retrieval analyses usingpetitRADTRANSto measure its chemical abundances, including the metallicity and C/O ratio, projected rotation velocity ( $v\sin i$), and radial velocity (RV). We found that the companion’s atmosphere has C/O $={0.55}_{-0.04}^{+0.06}$and [M/H] $={0.26}_{-0.23}^{+0.24}$(1σconfidence intervals), values consistent with those of the Sun and with a companion formation via gravitational instability or core accretion. The projected rotation velocity $v\sin \left(i\right)<7.8$km s⁻¹is small relative to other directly imaged companions with similar masses and ages. This may imply a nearly pole-on orientation or effective magnetic braking by a circumplanetary disk. In addition, we added the companion-to-primary relative RV measurement to the orbital fitting and obtained updated constraints on orbital parameters. Detailed characterization of super-Jovian companions within 20 au like HIP 99770 b is critical for understanding the formation histories of this population. 

The first scientific observations with adaptive optics (AO) at W. M. Keck Observatory (WMKO) began in 1999. Through 2023, over 1200 refereed science papers have been published using data from the WMKO AO systems. The scientific competitiveness of AO at WMKO has been maintained through a continuous series of AO and instrument upgrades and additions. This tradition continues with AO being a centerpiece of WMKO’s scientific strategic plan for 2035. We will provide an overview of the current and planned AO projects from the context of this strategic plan. The current projects include implementation of new real-time controllers, the KAPA laser tomography system and the HAKA high-order deformable mirror system, the development of multiple advanced wavefront sensing and control techniques, the ORCAS space-based guide star project, and three new AO science instruments. We will also summarize steps toward the future strategic directions which are centered on ground-layer, visible and high-contrast AO. 

Abstract The ~5 Myr PDS 70 is the only known system with protoplanets residing in the cavity of the circumstellar disk from which they formed, ideal for studying exoplanet formation and evolution within its natal environment. Here, we report the first spin constraint and C/O measurement of PDS 70b from Keck/KPIC high-resolution spectroscopy. We detected CO (3.8σ) and H₂O (3.5σ) molecules in the PDS 70b atmosphere via cross correlation, with a combined CO and H₂O template detection significance of 4.2σ. Our forward-model fits, using BT-Settl model grids, provide an upper limit for the spin rate of PDS 70b (<29 km s⁻¹). The atmospheric retrievals constrain the PDS 70b C/O ratio to ${0.28}_{-0.12}^{+0.20}$(<0.63 under 95% confidence level) and a metallicity [C/H] of ${-0.2}_{-0.5}^{+0.8}$dex, consistent with that of its host star. The following scenarios can explain our measured C/O of PDS 70b in contrast with that of the gas-rich outer disk (for which C/O ≳ 1). First, the bulk composition of PDS 70b might be dominated by dust+ice aggregates rather than disk gas. Another possible explanation is that the disk became carbon enrichedafterPDS 70b was formed, as predicted in models of disk chemical evolution and as observed in both very low-mass stars and older disk systems with JWST/MIRI. Because PDS 70b continues to accrete and its chemical evolution is not yet complete, more sophisticated modeling of the planet and the disk, and higher-quality observations of PDS 70b (and possibly PDS 70c), are necessary to validate these scenarios. 

Abstract We used the Keck Planet Imager and Characterizer to obtain high-resolution (R∼ 35,000)K-band spectra ofκAndromedae b, a planetary-mass companion orbiting the B9V star,κAndromedae A. We characterized its spin, radial velocity, and bulk atmospheric parameters through use of a forward-modeling framework to jointly fit planetary spectra and residual starlight speckles, obtaining likelihood-based posterior probabilities. We also detected H₂O and CO in its atmosphere via cross correlation. We measured a $v\sin \left(i\right)$value forκAndromedae b of 38.42 ± 0.05 km s⁻¹, allowing us to extend our understanding of the population of close-in bound companions at higher rotation rates. This rotation rate is one of the highest spins relative to breakup velocity measured to date, at close to 50% of breakup velocity. We identify a radial velocity $-{17.35}_{-0.09}^{+0.05}$km s⁻¹, which we use with existing astrometry and radial velocity measurements to update the orbital fit. We also measure an effective temperature of 1700 ± 100 K and a $\log \left(g\right)$of 4.7 ± 0.5 cgs dex. 

Abstract We present the projected rotational velocity and molecular abundances for HD 33632 Ab obtained via Keck Planet Imager and Characterizer (KPIC) high-resolution spectroscopy. HD 33632 Ab is a nearby benchmark brown dwarf companion at a separation of ∼20 au that straddles the L–T transition. Using a forward-modeling framework with on-axis host star spectra, which provides self-consistent substellar atmospheric and retrieval models for HD 33632 Ab, we derive a projected rotational velocity of 53 ± 3 km s⁻¹and carbon monoxide and water mass fractions of logCO = −2.3 ± 0.3 and logH₂O = −2.7 ± 0.2, respectively. The inferred carbon-to-oxygen ratio (C/O = 0.58 ± 0.14), molecular abundances, and metallicity ([C/H] = 0.0 ± 0.2 dex) of HD 33632 Ab are consistent with its host star. Although detectable methane opacities are expected in L–T transition objects, we did not recover methane in our KPIC spectra, partly due to the highvsiniand to disequilibrium chemistry at the pressures to which we are sensitive. We parameterize the spin as the ratio of rotation to the breakup velocity, and compare HD 33632 Ab to a compilation of >200 very low-mass objects (M≲ 0.1M_⊙) that have spin measurements in the literature. There appears to be no clear trend for the isolated low-mass field objects versus mass, but a tentative trend is identified for low-mass companions and directly imaged exoplanets, similar to previous findings. A larger sample of close-in gas giant exoplanets and brown dwarfs will critically examine our understanding of their formation and evolution through rotation and chemical abundance measurements.