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We present stellar rotation periods for late K- and early M-dwarf members of the 4 Gyr old open cluster M67 as calibrators for gyrochronology and tests of stellar spin-down models. Using Gaia EDR3 astrometry for cluster membership and Pan-STARRS (PS1) photometry for binary identification, we build this set of rotation periods from a campaign of monitoring M67 with the Canada-France-Hawaii Telescope's MegaPrime wide field imager. We identify 1807 members of M67, of which 294 are candidate single members with significant rotation period detections. Moreover, we fit a polynomial to the period versus color-derived effective temperature sequence observed in our data. We find that the rotation of very cool dwarfs can be explained by a simple solid-body spin-down between 2.7 and 4 Gyr. We compare this rotational sequence to the predictions of gyrochronological models and find that the best match is Skumanich-like spin-down, P_rot \propto t^0.62, applied to the sequence of Ruprecht 147. This suggests that, for spectral types K7-M0 with near-solar metallicity, once a star resumes spinning down, a simple Skumanich-like is sufficient to describe their rotation evolution, at least through the age of M67. Additionally, for stars in the range M1-M3, our data show that spin-down must have resumed prior to the age of M67, in conflict with predictions of the latest spin-down models., 21 pages, 16 figures, Accepted for publication by ApJ

Emerging Technologies which merge cyber-physical systems continue to transform businesses and digital agility in transformative ways. Importantly, most investigations around focus on either cyber risk or the risk around physical systems but it does not encompass both. However, the immediate challenge is new opportunities occurring with emerging technologies. Examples include automobiles, the Internet of Things (IoT), medical devices, and building controls. In this study we will focus identifying risk as an optimization not a minimization problem and how to develop a practical approach for executives and boards to use in the oversight of cyber physical systems. Based on interviews with executive leadership teams and boards of directors we explored the over-arching research question: How can we apply a risk-based approach to cyber-physical security and what questions should business leaders be asking? The research methodology used a survey instrument and multiple qualitative methods involving business leaders from 60 companies and 80 business leaders from September 2018 – September 2019. Based on this analysis, we developed an extended framework for executives, as well as questions and process for boards to consider as part of their oversight. The Extended Risk-Based Approach equips boards and executives as they begin to develop their thinking around enterprise cyber physical risk.

Direct imaging studies have mainly used low-resolution spectroscopy ($R\sim20-100$) to study the atmospheres of giant exoplanets and brown dwarf companions, but the presence of clouds has often led to degeneracies in the retrieved atmospheric abundances (e.g. C/O, metallicity). This precludes clear insights into the formation mechanisms of these companions. The Keck Planet Imager and Characterizer (KPIC) uses adaptive optics and single-mode fibers to transport light into NIRSPEC ($R\sim35,000$ in $K$ band), and aims to address these challenges with high-resolution spectroscopy. Using an atmospheric retrieval framework based on petitRADTRANS, we analyze KPIC high-resolution spectrum ($2.29-2.49~\mu$m) and archival low-resolution spectrum ($1-2.2~\mu$m) of the benchmark brown dwarf HD 4747 B ($m=67.2\pm1.8~M_{\rm{Jup}}$, $a=10.0\pm0.2$ au, $T_{\rm eff}\approx1400$ K). We find that our measured C/O and metallicity for the companion from the KPIC high-resolution spectrum agree with that of its host star within $1-2\sigma$. The retrieved parameters from the $K$ band high-resolution spectrum are also independent of our choice of cloud model. In contrast, the retrieved parameters from the low-resolution spectrum are highly sensitive to our chosen cloud model. Finally, we detect CO, H$_2$O, and CH$_4$ (volume mixing ratio of log(CH$_4$)=$-4.82\pm0.23$) in this L/T transition companion with the KPIC data. The relative molecular abundances allow us to constrain the degree of chemical disequilibrium in the atmosphere of HD 4747 B, and infer a vertical diffusion coefficient that is at the upper limit predicted from mixing length theory., Comment: 33 pages, 16 figures, Accepted to ApJ

Emerging technologies such as artificial intelligence, the Internet of Things, and distributed ledger continue to transform businesses, enabling new value creation in transformative ways. Their potential social impacts create risks. These risks are not easily identified or evaluated making it difficult to address them. There are upside and downside risks. Business leaders from companies deploying these technologies are initially interviewed. Development and preliminary testing of three different risk optimization models using scenario analysis data are informed by this information. Using this analysis, we introduce the foundations for a risk model and potentially a dashboard that executives could use to consider these technologies.

Objective Rush University Medical Center nursing leadership undertook a process improvement project to revamp nursing handoff during unit transfer with the goal of improving patient throughput. The aim was to decrease assign-to-occupy time, the duration from bed assignment to bed occupancy. Background There was a lengthy lag time in admitting/transferring patients, leading to delays in patient throughput and potential threats to patient safety. In fiscal year 2016, assign-to-occupy time averaged 97 minutes. The goal was to decrease that time to 60 minutes or less. Methods Process improvement leaders held a rapid improvement event to determine viable solutions. A team then standardized handoff workflow; created an electronic tool, virtually eliminating verbal report; and implemented a new handoff process. Results Assign-to-occupy time at 1 year after go-live averaged 55 minutes, and it has been staying less than 60 minutes since the implementation. Conclusions Key success strategies included engaging stakeholders during the rapid improvement event, imploring frontline nurses to create and promote the revised process to facilitate staff engagement, and leveraging electronic health records.

The Planetary Systems Imager (PSI) is a proposed instrument for the Thirty Meter Telescope (TMT) that provides an extreme adaptive optics (AO) correction to a multi-wavelength instrument suite optimized for high contrast science. PSI's broad range of capabilities, spanning imaging, polarimetry, integral field spectroscopy, and high resolution spectroscopy from 0.6-5 microns, with a potential channel at 10 microns, will enable breakthrough science in the areas of exoplanet formation and evolution. Here, we present a preliminary optical design and performance analysis toolset for the 2-5 microns component of the PSI AO system, which must deliver the wavefront quality necessary to support infrared high contrast science cases. PSI-AO is a two-stage system, with an initial deformable mirror and infrared wavefront sensor providing a common wavefront correction to all PSI science instruments followed by a dichroic that separates "PSI-Red" (2-5 microns) from "PSI-Blue" (0.5-1.8 microns). To meet the demands of visible-wavelength high contrast science, the PSI-Blue arm will include a second deformable mirror and a visible-wavelength wavefront sensor. In addition to an initial optical design of the PSI-Red AO system, we present a preliminary set of tools for an end-to-end AO simulation that in future work will be used to demonstrate the planet-to-star contrast ratios achievable with PSI-Red., 13 pages, 8 figures, submitted to SPIE Optical Engineering + Applications 2021, Techniques and Instrumentation for Detection of Exoplanets X

The Keck Planet Imager and Characterizer (KPIC) is a purpose-built instrument to demonstrate technological and instrumental concepts initially developed for the exoplanet direct imaging field. Located downstream of the current Keck II adaptive optic (AO) system, KPIC contains a fiber injection unit (FIU) capable of combining the high-contrast imaging capability of the AOs system with the high dispersion spectroscopy capability of the current Keck high resolution infrared spectrograph (NIRSPEC). Deployed at Keck in September 2018, this instrument has already been used to acquire high-resolution spectra (R > 30,000) of multiple targets of interest. In the near term, it will be used to spectrally characterize known directly imaged exoplanets and low-mass brown dwarf companions visible in the northern hemisphere with a spectral resolution high enough to enable spin and planetary radial velocity measurements as well as Doppler imaging of atmospheric weather phenomena. Here, we present the design of the FIU, the unique calibration procedures needed to operate a single-mode fiber instrument and the system performance.

Blockchain, or distributed ledger, continues to be deployed in the healthcare, energy, manufacturing, financial services sectors, and retail. Blockchain advocates argue that this technology constitutes a new architectural foundation for building trust based on its unique technological characteristics (Glaser 2017). However, cybersecurity is not a function of technological architecture but, in fact, is critically bound by human elements, processes, and actors. Therefore, all emerging technologies have cyber risk. Given the disruptive nature of this technology, there is a strong business need to understand cyber risk associated with blockchain. With this in mind, this investigation posed the following research questions: What are the risks associated with blockchain? Can a risk-based approach be validated or extended by exploring cases of blockchain deployment and highlighting risk? Multiple qualitative methods were used to analyze the data and to identify trends. This analysis identified cyber risk, in the context of blockchain, using the simple and generally accepted definition of cyber security as confidentiality, integrity, and availability (CIA). Based on the results, a cyber-physical risk-based approach was developed and blockchain deployment was examined in specific cases to identify and analyze the breaches according to this framework. The results demonstrate that beyond technological and data architecture there a strong need to further identify and analyze the cybercriminal actors and behavior in order to address cyber risk.

Emerging Technologies such as blockchain, continue to transform businesses. Blockchain, or distributed ledger, continues to be deployed in the healthcare, energy, manufacturing, and financial services sectors. Given the disruptive nature of this technology, there is a strong business need to understand the cyber risk associated with blockchain. With this in mind, this investigation posed the following research questions: What are the risks associated with blockchain? How can these risks be evaluated and integrated into corporate decision-making? Multiple quantitative and qualitative methods were used to analyze the data and to identify trends. This analysis identified cyber risk, in the context of blockchain, using the simple and generally accepted definition of cybersecurity as confidentiality, integrity, and availability (CIA). Based on the results, a cyber-physical risk-based approach is presented which equips executives as they develop their thinking around enterprise cyber risk, particularly with emerging technologies such as blockchain.

We present results from the Large Adaptive optics Survey for Substellar Objects (LASSO), where the goal is to directly image new substellar companions (11.8$), while only 23$^{+11}_{-6}$% of the remaining 22 stars with no detected companion have significant accelerations. The significance of the acceleration decreases with increasing companion separation. These young accelerating low-mass stars with companions will eventually yield dynamical masses with future orbit monitoring., 44 pages: 20 pages of text with 14 figures, 24 pages of tables in the appendix. Accepted for publication in the Astronomical Journal

International audience; Abstract Adaptive optics systems require a calibration procedure to operate, whether in closed loop or even more importantly in forward control. This calibration usually takes the form of an interaction matrix and is a measure of the response on the wavefront sensor to wavefront corrector stimulus. If this matrix is sufficiently well conditioned, it can be inverted to produce a control matrix, which allows to compute the optimal commands to apply to the wavefront corrector for a given wavefront sensor measurement vector. Interaction matrices are usually measured by means of an artificial source at the entrance focus of the adaptive optics system; however, adaptive secondary mirrors on Cassegrain telescopes offer no such focus and the measurement of their interaction matrices becomes more challenging and needs to be done on-sky using a natural star. The most common method is to generate a theoretical or simulated interaction matrix and adjust it parametrically (for example, decenter, magnification, rotation) using on-sky measurements. We propose a novel method of measuring on-sky interaction matrices ab initio from the telemetry stream of the AO system using random patterns on the deformable mirror with diagonal commands covariance matrices. The approach, being developed for the adaptive secondary mirror upgrade for the imaka wide-field AO system on the UH2.2m telescope project, is shown to work on-sky using the current imaka testbed.

An Adaptive secondary mirror (ASM) allows for the integration of adaptive optics (AO) into the telescope itself. Adaptive secondary mirrors, based on hybrid variable reluctance (HVR) actuator technology, developed by TNO, provide a promising path to telescope-integrated AO. HVR actuators have the advantage of allowing mirrors that are stiffer, more power efficient, and potentially less complex than similar, voice-coil based ASM's. We are exploring the application of this technology via a laboratory testbed that will validate the technical approach. In parallel, we are developing conceptual designs for ASMs at several telescopes including the Automated Planet Finder Telescope (APF) and for Keck Observatory. An ASM for APF has the potential to double the light through the slit for radial velocity measurements, and dramatically improved the image stability. An ASM for WMKO enables ground layer AO correction and lower background infrared AO observations, and provides for more flexible deployment of instruments via the ability to adjust the location of the Cassegrain focus., Comment: 16 pages, Proceedings of SPIE

The Keck Planet Imager and Characterizer (KPIC) is a purpose-built instrument to demonstrate new tech- nological and instrumental concepts initially developed for the exoplanet direct imaging field. Located downstream of the current Keck II adaptive optic system, KPIC contains a fiber injection unit (FIU) capable of combining the high-contrast imaging capability of the adaptive optic system with the high dispersion spectroscopy capability of the current Keck high resolution infrared spectrograph (NIRSPEC). Deployed at Keck in September 2018, this instrument has already been used to acquire high resolution spectra (R < 35, 000) of multiple targets of interest. In the near term, it will be used to spectrally characterize known directly imaged exoplanets and low-mass brown dwarf companions visible in the northern hemisphere with a spectral resolution high enough to enable spin and planetary radial velocity measurements as well as Doppler imaging of atmospheric weather phenomena. Here we present the design of the FIU, the unique calibration procedures needed to operate a single-mode fiber instrument and the system performance.

In this report, we present an optical design for a 3-sided reflective pyramid wavefront sensor which allows for the imaging of the pupils onto a single detector. A general approach for this reflective design is demonstrated; however, in effort to implement the optical system into the Shane Telescope’s adaptive optics module, this reflective pyramid wavefront sensor design is constrained by the module’s current specifications. Due to the physical constraints in the AO module, the developed optical design shares an undeviated optical axis with a transmissive wedge solution for discrete modulation. Pupil images were created using a lab test bench that demonstrates the design’s proof of concept. We will discuss the details of the optical design and its motivating parameters using the Shane Telescope’s adaptive optics module.

International audience; We are developing a new adaptive secondary mirror (ASM) for the University of Hawaii 2.2-meter telescope based on a novel and very efficient hybrid variable reluctance actuator developed by TNO. The actuator technology has broad implications on the ASM design and results in an ASM with a thicker facesheet, lower power dissipation, and simple controls. We report here preparations and plans for lab testing as well as on-sky demonstration of the ASM. The lab calibrations of the ASM influence functions will use a phase measuring deflectometry setup. The on-sky tests will include the evaluation of the use of the ASM for narrow field AO observations at visible through near infrared wavelengths, for very wide fields of view ground-layer adaptive optics, and for seeing limited non-adaptive optics observations.

An adaptive secondary mirror (ASM) is currently being developed for the UH2.2 telescope, consisting of a slumped 620mm convex aspherical facesheet, manipulated by 210 variable-reluctance actuators and supported on a silicon aluminium alloy support structure. The total power dissipation of the actuators is expected to be under 3 Watts. The ASM will weigh around 55kg, which is about 15kg lighter than the original passive secondary mirror (M2). We present the design, breadboarding activities and manufacturing status of this adaptive mirror. The project is on track for delivery of the ASM in Hawaii in the middle of 2021.

International audience; The study of cold or obscured, red astrophysical sources can significantly benefit from adaptive optics (AO) systems employing infrared (IR) wavefront sensors. One particular area is the study of exoplanets around M-dwarf stars and planet formation within protoplanetary disks in star-forming regions. Such objects are faint at visible wavelengths but bright enough in the IR to be used as a natural guide star for the AO system. Doing the wavefront sensing at IR wavelengths enables high-resolution AO correction for such science cases, with the potential to reach the contrasts required for direct imaging of exoplanets. To this end, a new near-infrared pyramid wavefront sensor (PyWFS) has been added to the Keck II AO system, extending the performance of the facility AO system for the study of faint red objects. We present the Keck II PyWFS, which represents a number of firsts, including the first PyWFS installed on a segmented telescope and the first use of an IR PyWFS on a 10-m class telescope. We discuss the scientific and technological advantages offered by IR wavefront sensing and present the design and commissioning of the Keck PyWFS. In particular, we report on the performance of the Selex Avalanche Photodiode for HgCdTe InfraRed Array detector used for the PyWFS and highlight the novelty of this wavefront sensor in terms of the performance for faint red objects and the improvement in contrast. The system has been commissioned for science with the vortex coronagraph in the NIRC2 IR science instrument and is being commissioned alongside a new fiber injection unit for NIRSPEC. We present the first science verification of the system-to facilitate the study of exoplanets around M-type stars.

We present $L$'-band imaging of the PDS 70 planetary system with Keck/NIRC2 using the new infrared pyramid wavefront sensor. We detected both PDS 70 b and c in our images, as well as the front rim of the circumstellar disk. After subtracting off a model of the disk, we measured the astrometry and photometry of both planets. Placing priors based on the dynamics of the system, we estimated PDS 70 b to have a semi-major axis of $20^{+3}_{-4}$~au and PDS 70 c to have a semi-major axis of $34^{+12}_{-6}$~au (95\% credible interval). We fit the spectral energy distribution (SED) of both planets. For PDS 70 b, we were able to place better constraints on the red half of its SED than previous studies and inferred the radius of the photosphere to be 2-3~$R_{Jup}$. The SED of PDS 70 c is less well constrained, with a range of total luminosities spanning an order of magnitude. With our inferred radii and luminosities, we used evolutionary models of accreting protoplanets to derive a mass of PDS 70 b between 2 and 4 $M_{\textrm{Jup}}$ and a mean mass accretion rate between $3 \times 10^{-7}$ and $8 \times 10^{-7}~M_{\textrm{Jup}}/\textrm{yr}$. For PDS 70 c, we computed a mass between 1 and 3 $M_{\textrm{Jup}}$ and mean mass accretion rate between $1 \times 10^{-7}$ and $5 \times~10^{-7} M_{\textrm{Jup}}/\textrm{yr}$. The mass accretion rates imply dust accretion timescales short enough to hide strong molecular absorption features in both planets' SEDs., Comment: 20 pages, 5 figures, Accepted to AJ. Updated author list from original version. Fixed equation typo

We have developed a turbulence sensor to study image degradation in domes of astronomical observatories. A prototype has already been deployed at sites such as CFHT, UH88” and LBT, revealing the effects of minute temperature differences, dome venting and the amplification of non-Kolmogorov turbulence by adaptive optics.

Background Early implant placement combined with simultaneous contour augmentation was able to rebuild stable facial hard-tissue and soft-tissue contours that were esthetically pleasing. The purpose of this study was to evaluate the clinical esthetic outcome, when two different bone grafting materials were used. Methods Forty-eight patients were randomly assigned into two groups. In the control group, autogenous bone was used to cover the exposed implant surface then a layer of deproteinized bovine bone mineral (DBBM) was added. This graft combination was then combined with a collagen membrane. In the test group, the exposed implant surface was covered with a layer of freeze-dried bone allograft (FDBA) in combination with the collagen membrane. Modified plaque index (mPI), modified sulcular bleeding index (mSBI), probing depth (PD), keratinized mucosa (KM), implant crown length (IC), distance from the implant shoulder radiographic bone-to-implant contact (DIB), pink esthetic score (PES), and white esthetic score (WES) were measured at 12-months post implant loading. Results All 48 implants were clinically successful, and no significant differences were observed in mPI, mSBI, PD, KM, IC, DIB, PES, and WES at 1-year implant loading. The mean mucosal recessions of test and control group were unchanged, 0 and -0.02 mm, respectively. The mean DIB were -0.32 and -0.21 mm in test and control implants, respectively. The mean totals of PES/WES were 15.29 and 15.33 for the test and control groups, respectively, with no significant difference between groups. Conclusion This study demonstrated that autogenous bone plus DBBM and FDBA each combined with a collagen membrane both resulted in stable clinical and esthetic outcomes in early implant placement with contour augmentation after 1 year.

Using the Keck Planet Imager and Characterizer (KPIC), we obtained high-resolution (R$\sim$35,000) $K$-band spectra of the four planets orbiting HR 8799. We clearly detected \water{} and CO in the atmospheres of HR 8799 c, d, and e, and tentatively detected a combination of CO and \water{} in b. These are the most challenging directly imaged exoplanets that have been observed at high spectral resolution to date when considering both their angular separations and flux ratios. We developed a forward modeling framework that allows us to jointly fit the spectra of the planets and the diffracted starlight simultaneously in a likelihood-based approach and obtained posterior probabilities on their effective temperatures, surface gravities, radial velocities, and spins. We measured $v\sin(i)$ values of $10.1^{+2.8}_{-2.7}$~km/s for HR 8799 d and $15.0^{+2.3}_{-2.6}$~km/s for HR 8799 e, and placed an upper limit of $< 14$~km/s of HR 8799 c. Under two different assumptions of their obliquities, we found tentative evidence that rotation velocity is anti-correlated with companion mass, which could indicate that magnetic braking with a circumplanetary disk at early times is less efficient at spinning down lower mass planets., 31 pages, 12 figures, Accepted to AJ

The Keck Planet Imager and Characterizer (KPIC) is an upgrade to the Keck II adaptive optics system enabling high contrast imaging and high-resolution spectroscopic characterization of giant exoplanets in the mid-infrared (2-5 microns). The KPIC instrument will be developed in phases. Phase I entails the installation of an infrared pyramid wavefront sensor (PyWFS) based on a fast, low-noise SAPHIRA IR-APD array. The ultra-sensitive infrared PyWFS will enable high contrast studies of infant exoplanets around cool, red, and/or obscured targets in star forming regions. In addition, the light downstream of the PyWFS will be coupled into an array of single-mode fibers with the aid of an active fiber injection unit (FIU). In turn, these fibers route light to Keck's high-resolution infrared spectrograph NIRSPEC, so that high dispersion coronagraphy (HDC) can be implemented for the first time. HDC optimally pairs high contrast imaging and high-resolution spectroscopy allowing detailed characterization of exoplanet atmospheres, including molecular composition, spin measurements, and Doppler imaging. We will provide an overview of the instrument, its science scope, and report on recent results from on-sky commissioning of Phase I. We will discuss plans for optimizing the instrument to seed designs for similar modes on extremely large telescopes.

We present individual dynamical masses for the nearby M9.5+T5.5 binary WISE J072003.20$-$084651.2AB, a.k.a. Scholz's star. Combining high-precision CFHT/WIRCam photocenter astrometry and Keck adaptive optics resolved imaging, we measure the first high-quality parallactic distance ($6.80_{-0.06}^{+0.05}$ pc) and orbit ($8.06_{-0.25}^{+0.24}$ yr period) for this system composed of a low-mass star and brown dwarf. We find a moderately eccentric orbit ($e = 0.240_{-0.010}^{+0.009}$), incompatible with previous work based on less data, and dynamical masses of $99\pm6$ $M_{\rm Jup}$ and $66\pm4$ $M_{\rm Jup}$ for the two components. The primary mass is marginally inconsistent (2.1$\sigma$) with the empirical mass$-$magnitude$-$metallicity relation and models of main-sequence stars. The relatively high mass of the cold ($T_{\rm eff} = 1250\pm40$ K) brown dwarf companion indicates an age older than a few Gyr, in accord with age estimates for the primary star, and is consistent with our recent estimate of $\approx$70 $M_{\rm Jup}$ for the stellar/substellar boundary among the field population. Our improved parallax and proper motion, as well as an orbit-corrected system velocity, improve the accuracy of the system's close encounter with the solar system by an order of magnitude. WISE J0720$-$0846AB passed within $68.7\pm2.0$ kAU of the Sun $80.5\pm0.7$ kyr ago, passing through the outer Oort cloud where comets can have stable orbits., Comment: accepted to AJ

International audience; Gemini Observatory plans to revitalize its AO facility at Gemini North for the benefit of the US and international user community, including a funded MCAO system now in development. Our Strategic Plan calls for the development of a GLAO system enabled by an Adaptive Secondary Mirror. We discuss our plans, progress, and funding outlook.

Adaptive optics (AO) systems deliver high-resolution images that may be ideal for precisely measuring positions of stars (i.e. astrometry) if the system has stable and well-calibrated geometric optical distortions. A calibration unit, equipped with back-illuminated pinhole mask, can be utilized to measure instrumental optical distortions. AO systems on the largest ground-based telescopes, such as the W. M. Keck Observatory and the Thirty Meter Telescope require pinhole positions known to 20 nm to achieve an astrometric precision of 0.001 of a resolution element. We characterize a photo-lithographic pinhole mask and explore the systematic errors that result from different experimental setups. We characterized the nonlinear geometric distortion of a simple imaging system using the mask; and we measured 857 nm RMS of optical distortion with a final residual of 39 nm (equivalent to 20 ��as for TMT). We use a sixth order bivariate Legendre polynomial to model the optical distortion and allow the reference positions of the individual pinholes to vary. The nonlinear deviations in the pinhole pattern with respect to the manufacturing design of a square pattern are 47.2 nm +/- 4.5 nm (random) +/- 10.8 nm (systematic) over an area of 1788 mm$^2$. These deviations reflect the additional error induced when assuming the pinhole mask is manufactured perfectly square. We also find that ordered mask distortions are significantly more difficult to characterize than random mask distortions as the ordered distortions can alias into optical camera distortion. Future design simulations for astrometric calibration units should include ordered mask distortions. We conclude that photo-lithographic pinhole masks are >10 times better than the pinhole masks deployed in first generation AO systems and are sufficient to meet the distortion calibration requirements for the upcoming thirty meter class telescopes., 20 pages, 13 figures

International audience; Gemini Observatory has been awarded from the National Science Foundation a major fund to build a new state-of-the-art Multi Conjugate Adaptive Optics facility for Gemini North on Maunakea called GNAO. The current Telephone: 1+56 51 2205 642 baseline system will use two lasers each split in two to create an artificial constellation of four laser guide star to measure the distortions caused by the atmosphere. At least two deformable mirror conjugated to 0km and the main altitude layer above Maunakea will be used to correct these distortions. The facility will be designed to feed future instrumentation, initially a near infrared imager and potentially a visiting 4-arm multi object adaptive optics IFU spectrograph. 1 In this paper I will present the main characteristics of this exciting facility, its promises and its challenges. I will also present its conceptual design and results of trade studies conducted within the team and the Gemini Adaptive Optics Working Group. The expected first light is for October 2024.

Emerging Technologies such as artificial intelligence, the Internet of Things (IoT), and distributed ledger continue to transform businesses, enabling new value creation in transformative ways. Importantly, most investigations and the broader scholarly discourse is around applications. In addition to the potential impacts on society, these technologies create risks, which even in the corporate context are not easily identified or evaluated and therefore cannot be easily addressed. The risks are both upside risks (opportunities or rewards) and downside risks (exposures that jeopardize the company). Can these risks be identified and evaluated? If so, what models might work for evaluating and perhaps even optimizing risk? In this study, we will first explore what technologies are being deployed and where the organizational risk is being considered or evaluated from a governance perspective within the organization. Based on interviews with executives facing these new environments, we developed the over-arching research questions: What theories guide our thinking best in terms of developing risk optimization models? What might these risk models look like? The research involved an exploration using a survey instrument and multiple qualitative methods involving business leaders from companies deploying these technologies as well as the development and preliminary testing of three different risk optimization models using scenario analysis data. Based on this analysis, we developed the foundations for a risk model executives could use to consider these technologies.

Cloud computing and the Internet of Things (IoT) have transformed businesses, enabling agile and costeffective IT infrastructure. The challenge is that these new opportunities create a co-mingled architecture which is difficult to secure. The complexity of this architecture is magnified with the IoT. Based on interviews with executive leadership teams and boards of directors facing these new environments, we developed the over-arching research question: How do we secure increasingly dynamic architecture in an environment while supporting and creating agile business growth? We then narrowed this down to more specific questions dealt with in this study. The research involved an in-depth exploration of this problem using a survey instrument and multiple qualitative methods involving business leaders from 59 companies between 2017 – 2018. Based on this analysis, we developed an information security framework for executives in this new environment that builds on previous work. This framework is called the Extended Risk-Based Approach and provides businesses with an approach for securing an enterprise amidst the IoT and agile architecture. Importantly, the data analyzed suggests that this approach is critically needed to address the rapidly growing complexity of enterprise architecture and the digital world we live and work.

Wavefront sensing and control are important for enabling one of the key advantages of using large apertures, namely higher angular resolutions. Pyramid wavefront sensors are becoming commonplace in new instrument designs owing to their superior sensitivity. However, one remaining roadblock to their widespread use is the fabrication of the pyramidal optic. This complex optic is challenging to fabricate due to the pyramid tip, where four planes need to intersect in a single point. Thus far, only a handful of these have been produced due to the low yields and long lead times. To address this, we present an alternative implementation of the pyramid wavefront sensor that relies on two roof prisms instead. Such prisms are easy and inexpensive to source. We demonstrate the successful operation of the roof prism pyramid wavefront sensor on a 8-m class telescope, at visible and near infrared wavelengths ---for the first time using a SAPHIRA HgCdTe detector without modulation for a laboratory demonstration---, and elucidate how this sensor can be used more widely on wavefront control test benches and instruments., Comment: Accepted for publication in PASP, 7 pages, 9 figures, 1 table

International audience

High-contrast imaging of exoplanets and protoplanetary disks depends on wavefront sensing and correction made by adaptive optics instruments. Classically, wavefront sensing has been conducted at optical wavelengths, which made high-contrast imaging of red targets such as M-type stars or extincted T Tauri stars challenging. Keck/NIRC2 has combined near-infrared (NIR) detector technology with the pyramid wavefront sensor (PWFS). With this new module we observed SR~21, a young star that is brighter at NIR wavelengths than at optical wavelengths. Compared with the archival data of SR~21 taken with the optical wavefront sensing we achieved $\sim$20\% better Strehl ratio in similar natural seeing conditions. Further post-processing utilizing angular differential imaging and reference-star differential imaging confirmed the spiral feature reported by the VLT/SPHERE polarimetric observation, which is the first detection of the SR~21 spiral in total intensity at $L^\prime$ band. We also compared the contrast limit of our result ($10^{-4}$ at $0\farcs4$ and $2\times10^{-5}$ at $1\farcs0$) with the archival data that were taken with optical wavefront sensing and confirmed the improvement, particularly at $\leq0\farcs5$. Our observation demonstrates that the NIR PWFS improves AO performance and will provide more opportunities for red targets in the future., accepted for publication in AJ, 8 pages, 7 figures

The TIKI instrument is a next generation 10-micron cryogenic extreme adaptive optics (ExAO) imager being designed for the Gemini South telescope. Its goal is to detect the thermal emission of Earth-like planets in orbit around Alpha Centauri A or B. TIKI is also a prototype for future TMT instruments capable of imaging Earth- like planets around a larger star sample, and performing low spectral resolution characterization to search for biomarkers on detected planets. The science module will operate at cryogenic temperature in order to minimize thermal background, dominant in the 10-micron wavelength range. The instrument will use Adaptive Optics, a vortex coronagraph, focal plane wavefront sensing, and advanced post-processing techniques to reach a 1E-7 contrast in less than 200 hours of observing time. It aims to be background-limited in the 2-5λ/D zone, which corresponds to the habitable zone around the two Sun-like stars of the Alpha Centauri system. In this paper, we give an overview of the project goals, present TIKI's conceptual optical design, and summarize preliminary simulation results.

With the imminent launch of the JWST, the field of thermal-infrared (TIR) astronomy will enjoy a revolution. It is easy to imagine that all areas of infrared (IR) astronomy will be greatly advanced, but perhaps impossible to conceive of the new vistas that will be opened. To allow both follow-up JWST observations and a continuance of work started on the ground-based 8m’s, we continue to plan the science cases and instrument design for a TIR imager and spectrometer for early operation on the TMT. We present the current status of our science cases and the instrumentation plans, harnessing expertise across the TMT partnership. This instrument will be proposed by the MICHI team as a second-generation instrument in any upcoming calls for proposals., Ground-based and Airborne Instrumentation for Astronomy VII, June 10-15, 2018, Austin, USA, Series: Proceedings of SPIE; no. 10702

A near-infrared, high order pyramid wavefront sensor will be implemented on the Keck telescope, with the aim of providing high resolution adaptive optics correction for the study of exoplanets around M-type stars and planet formation in obscured star forming regions. The pyramid wavefront sensor is designed to support adaptive optics correction of the light to an imaging vortex coronagraph and to a fiber injection unit that will feed a spectrograph. We present the opto-mechanical design of the near-infrared pyramid wavefront sensor, the optical performance, and the alignment strategy. The challenges of designing the assembly, as well as a fiber injection unit, to fit into the limited available space on the Keck adaptive optics bench, will also be discussed., Adaptive Optics Systems VI, June 10-15, 2018, Austin, TX, USA, Series: Proceedings of SPIE; no. 10703

A new real-time control system will be implemented within the Keck II adaptive optics system to support the new near-infrared pyramid wavefront sensor. The new real-time computer has to interface with an existing, very productive adaptive optics system. We discuss our solution to install it in an operational environment without impacting science. This solution is based on an independent SCExAO-based pyramid wavefront sensor realtime processor solution using the hardware interfaces provided by the existing Keck II real-time controller. We introduce the new pyramid real-time controller system design, its expected performance, and the modification of the operational real-time controller to support the pyramid system including interfacing with the existing deformable and tip-tilt mirrors. We describe the integration of the Saphira detector-based camera and the Boston Micromachines kilo-DM in this new architecture. We explain the software architecture and philosophy, the shared memory concept and how the real-time computer uses the power of GPUs for adaptive optics control. We discuss the strengths and weaknesses of this architecture and how it can benefit other projects. The motion control of the devices deployed on the Keck II adaptive optics bench to support the alignment of the light on the sensors is also described. The interfaces, developed to deal with the rest of the Keck telescope systems in the observatory distributed system, are reviewed. Based on this experience, we present which design ideas could have helped us integrate the new system with the previous one and the resultant performance gains.

We report on initial results from the largest infrared AO direct imaging survey searching for wide orbit (>100 AU) massive exoplanets and brown dwarfs as companions around young nearby stars using Robo-AO at the 2.1-m telescope on Kitt Peak, Arizona. The occurrence rates of these rare substellar companions are critical to furthering our understanding of the origin of planetary-mass companions on wide orbits. The observing efficiency of Robo-AO allows us to conduct a survey an order of magnitude larger than previously possible. We commissioned a low-noise high-speed SAPHIRA near-infrared camera to conduct this survey and report on its sensitivity, performance, and data reduction process., 10 pages, 7 figures, SPIE conference proceedings

We are building a next-generation laser adaptive optics system, Robo-AO-2, for the UH 2.2-m telescope that will deliver robotic, diffraction-limited observations at visible and near-infrared wavelengths in unprecedented numbers. The superior Maunakea observing site, expanded spectral range and rapid response to high-priority events represent a significant advance over the prototype. Robo-AO-2 will include a new reconfigurable natural guide star sensor for exquisite wavefront correction on bright targets and the demonstration of potentially transformative hybrid AO techniques that promise to extend the faintness limit on current and future exoplanet adaptive optics systems., Comment: 15 pages

Since the start of operations in 1993, the twin 10 meter W. M. Keck Observatory telescopes have continued to maximize their scientific impact and to produce transformative discoveries that keep the observing community on the frontiers of astronomical research. Upgraded capabilities and new instrumentation are provided though collaborative partnerships with Caltech and UC instrument development teams. The observatory adapts and responds to the observers’ evolving needs as defined in the observatory’s strategic plan, periodically refreshed in collaboration with the science community. This paper summarizes the performance of recently commissioned infrastructure projects, technology upgrades, and new additions to the suite of instrumentation at the observatory. We will also provide a status of projects currently in the design or development phase, and since we need to keep our eye on the future, we mention projects in exploratory phases that originate from our strategic plan. Recently commissioned projects include telescope control system upgrades, OSIRIS spectrometer and imager upgrades, and deployments of the Keck Cosmic Web Imager (KCWI), the Near-Infrared Echellette Spectrometer (NIRES), and the Keck I Deployable Tertiary Mirror (KIDM3). Under development are upgrades to the NIRSPEC instrument and adaptive optics (AO) system. Major instrumentation in design phases include the Keck Cosmic Reionization Mapper and the Keck Planet Finder. Future instrumentation studies and proposals underway include a Ground Layer Adaptive Optics system, NIRC2 upgrades, the energy sensitive instrument KRAKENS, an integral field spectrograph LIGER, and a laser tomography AO upgrade. Last, we briefly discuss recovering MOSFIRE and its return to science operations.

Ground-layer adaptive optics (GLAO) systems offer the possibility of improving the "seeing" of large ground-based telescopes and increasing the efficiency and sensitivity of observations over a wide field-of-view. We explore the utility and feasibility of deploying a GLAO system at the W. M. Keck Observatory in order to feed existing and future multi-object spectrographs and wide-field imagers. We also briefly summarize science cases spanning exoplanets to high-redshift galaxy evolution that would benefit from a Keck GLAO system. Initial simulations indicate that a Keck GLAO system would deliver a 1.5x and 2x improvement in FWHM at optical (500 nm) and infrared (1.5 micron), respectively. The infrared instrument, MOSFIRE, is ideally suited for a Keck GLAO feed in that it has excellent image quality and is on the telescope's optical axis. However, it lacks an atmospheric dispersion compensator, which would limit the minimum usable slit size for long-exposure science cases. Similarly, while LRIS and DEIMOS may be able to accept a GLAO feed based on their internal image quality, they lack either an atmospheric dispersion compensator (DEIMOS) or flexure compensation (LRIS) to utilize narrower slits matched to the GLAO image quality. However, some science cases needing shorter exposures may still benefit from Keck GLAO and we will investigate the possibility of installing an ADC., Comment: 2018 Proceedings of the SPIE; published