Supernovae from Red Supergiants with Extensive Mass Loss

We calculate multicolor light curves (LCs) of supernovae (SNe) from red supergiants (RSGs) exploded within dense circumstellar medium (CSM). Multicolor LCs are calculated by using a multi-group radiation hydrodynamics code STELLA. If CSM is dense enough, the shock breakout signal is delayed and smeared by CSM and kinetic energy of SN ejecta is efficiently converted to thermal energy which is eventually released as radiation. We find that explosions of RSGs are affected by CSM in early epochs when mass-loss rate just before the explosions is higher than 10^{-4} Msun/yr. Their characteristic features are that the LC has a luminous round peak followed by a flat LC, that multicolor LCs are simultaneously bright in ultraviolet and optical at the peak, and that photospheric velocity is very low at these epochs. We calculate LCs for various CSM conditions and explosion properties, i.e., mass-loss rates, radii of CSM, density slopes of CSM, explosion energies of SN ejecta, and SN progenitors inside, to see their influence on LCs. We compare our model LCs to those of ultraviolet-bright Type IIP SN 2009kf and show that the mass-loss rate of the progenitor of SN 2009kf just before the explosion is likely to be higher than 10^{-4} Msun/yr. Combined with the fact that SN 2009kf is likely to be an energetic explosion and has large 56Ni production, which implies that the progenitor of SN 2009kf is a massive RSG, our results indicate that there could be some mechanism to induce extensive mass loss in massive RSGs just before their explosions.Comment: 16 pages, 17 figures, 3 tables, accepted by Monthly Notices of the Royal Astronomical Society, the unit of Lbol in Table 3 corrected in v

Contour-map encoding of shape for early vision

Contour maps provide a general method for recognizing 2-D shapes. All but blank images give rise to such maps, and people are good at recognizing objects and shapes from them. The maps are encoded easily in long feature vectors that are suitable for recognition by an associative memory. These properties of contour maps suggest a role for them in early visual perception. The prevalence of direction sensitive neurons in the visual cortex of mammals supports this view

Inhomogeneous source uniformization using a shell mixer Köhler integrator

High flux and high CRI may be achieved by combining different chips and/or phosphors. This, however, results in inhomogeneous sources that, when combined with collimating optics, typically produce patterns with undesired artifacts. These may be a combination of spatial, angular or color non-uniformities. In order to avoid these effects, there is a need to mix the light source, both spatially and angularly. Diffusers can achieve this effect, but they also increase the etendue (and reduce the brightness) of the resulting source, leading to optical systems of increased size and wider emission angles. The shell mixer is an optic comprised of many lenses on a shell covering the source. These lenses perform Kohler integration to mix the emitted light, both spatially and angularly. Placing it on top of a multi-chip Lambertian light source, the result is a highly homogeneous virtual source (i.e, spatially and angularly mixed), also Lambertian, which is located in the same position with essentially the same size (so the average brightness is not increased). This virtual light source can then be collimated using another optic, resulting in a homogeneous pattern without color separation. Experimental measurements have shown optical efficiency of the shell of 94%, and highly homogeneous angular intensity distribution of collimated beams, in good agreement with the ray-tracing simulations

Twenty-Second Lunar and Planetary Science Conference

The papers in this collection were written for general presentation, avoiding jargon and unnecessarily complex terms. Some of the topics covered include: planetary evolution, planetary satellites, planetary composition, planetary surfaces, planetary geology, volcanology, meteorite impacts and composition, and cosmic dust. Particular emphasis is placed on Mars and the Moon

A Material Investigation of Color Film Technology through the Koshofer Collection

The Koshofer collection is an invaluable resource about the history of color film technology from the late nineteenth century until the 1980s, including film frames from early applied hand coloring, tinting and stencil coloring, to mimetic color processes such as Kinemacolor, Gasparcolor, and many other rare and popular color film stocks. Multispectral imaging in the visible range has been carried out to characterize the optical properties of the color processes, and an extensive microscopic examination allowed to reveal minute material features. These investigations highlight distinctive elements for the identification of some of the most significant historical color processes on film, and at the same time, offer crucial information for classical restoration techniques and for rigorous digitization strategies

Experimental and simulation study results for video landmark acquisition and tracking technology

A synopsis of related Earth observation technology is provided and includes surface-feature tracking, generic feature classification and landmark identification, and navigation by multicolor correlation. With the advent of the Space Shuttle era, the NASA role takes on new significance in that one can now conceive of dedicated Earth resources missions. Space Shuttle also provides a unique test bed for evaluating advanced sensor technology like that described in this report. As a result of this type of rationale, the FILE OSTA-1 Shuttle experiment, which grew out of the Video Landmark Acquisition and Tracking (VILAT) activity, was developed and is described in this report along with the relevant tradeoffs. In addition, a synopsis of FILE computer simulation activity is included. This synopsis relates to future required capabilities such as landmark registration, reacquisition, and tracking

Persistent Challenges of Quantum Chromodynamics

Unlike some models whose relevance to Nature is still a big question mark, Quantum Chromodynamics will stay with us forever. Quantum Chromodynamics (QCD), born in 1973, is a very rich theory supposed to describe the widest range of strong interaction phenomena: from nuclear physics to Regge behavior at large E, from color confinement to quark-gluon matter at high densities/temperatures (neutron stars); the vast horizons of the hadronic world: chiral dynamics, glueballs, exotics, light and heavy quarkonia and mixtures thereof, exclusive and inclusive phenomena, interplay between strong forces and weak interactions, etc. Efforts aimed at solving the underlying theory, QCD, continue. In a remarkable entanglement, theoretical constructions of the 1970s and 1990s combine with today's ideas based on holographic description and strong-weak coupling duality, to provide new insights and a deeper understanding.Comment: Julius Edgar Lilienfeld Prize Lecture at the April Meeting of APS, Dallas, TX, April 22-25, 2006; v.2: reference added; v.3: reference adde

The First-Ever Asteroid Fly-By Performed by a CubeSat: Outcomes of the LICIACube Mission

Transported onboard NASA Double Asteroid Redirection Test (in short, DART) spacecraft developed by Johns Hopkins Applied Physics Laboratory (APL), the Italian Space Agency (ASI) Light Italian CubeSat for Imaging of Asteroids (in short, LICIACube) played a crucial role in the homonymous mission that took place in September 2022. Its main purpose has been to document the effects of the intentional impact of DART probe with Dimorphos, the minor-planet moon of the 65803 Didymos asteroid system. Along this first-ever planetary defense mission against Near-Earth Objects (NEOs), LICIACube successfully completed the first-ever asteroid fly-by performed by a CubeSat. With a maximum Earth distance of approximately 14 million km during its operative phase, LICIACube is currently one of the nanosatellites that operated the farthest from our planet in a robotic exploration mission. Once separated from DART, the micro-satellite followed its mothercraft along its approach trajectory: its optical system, composed by two digital cameras, is the core of the Autonomous Attitude Control System which allowed to gather images of the two asteroids during a very fast fly-by. This paper discusses how LICIACube behaved in flight, with a focus on the embedded real-time hardware-accelerated imaging capabilities and the Autonomous Attitude Control System as a whole. These technologies allowed the CubeSat to simultaneously operate its two optical payloads both for tracking and science purposes. During the approximately 5-minute-long fly-by, tracking has been performed using the primary telescopic grayscale camera (LICIACube Explorer Imaging for Asteroid, LEIA) to provide rapid feedback to the satellite Autonomous Attitude Control System controlling its attitude, thus maintaining the pointing towards the target. The telescope was exploited to track the main body (Didymos) during the initial phases of the fly-by, switching then to Dimorphos in the vicinity of the closest approach, which occurred with a distance of about 50km and a relative speed of approximately 7 km/s. On the other hand, the secondary payload allowed to capture and store wide-angle images of DART impact with the asteroid, by means of the secondary RGB camera (LICIACube Unit Key Explorer, LUKE) and with a maximum image acquisition rate of 3 pictures per second. In the first section of this paper, the LICIACube CubeSat System is introduced in the DART mission context. In second place, Argotec\u27s all-in-house HAWK-6 platform upon which LICIACube was built is discussed in detail. Followingly, LICIACube in-flight performances are examined with a focus on the Autonomous Attitude Control System. Mission results are included, with real-time telemetry data collected during operations and images of DART captured before and after the impact with Dimorphos

Bioluminescence imaging on-chip platforms for non-invasive high-content bioimaging

Incorporating non-invasive biosensing features in organ-on-chip models is of paramount importance for a wider implementation of these advanced in vitro microfluidic platforms. Optical biosensors, based on Bioluminescence Imaging (BLI), enable continuous, non-invasive, and in-situ imaging of cells, tissues or miniaturized organs without the drawbacks of conventional fluorescence imaging. Here, we report the first-of-its-kind integration and optimization of BLI in microfluidic chips, for non-invasive imaging of multiple biological readouts. The cell line HEK293T-GFP was engineered to express NanoLuc® luciferase under the control of a constitutive promoter and were cultured on-chip in 3D, in standard ECM-like hydrogels, to assess optimal cell detection conditions. Using real-time in-vitro dual-color microscopy, Bioluminescence (BL) and fluorescence (FL) were detectable using distinct imaging setups. Detection of the bioluminescent signals were observed at single cell resolution on-chip 20 min post-addition of Furimazine substrate and under perfusion. All hydrogels enabled BLI with higher signal-to-noise ratios as compared to fluorescence. For instance, agarose gels showed a ∼5-fold greater BL signal over background after injection of the substrate as compared to the FL signal. The use of BLI with microfluidic chip technologies opens up the potential for simultaneous in situ detection with continuous monitoring of multicolor cell reporters. Moreover, this can be achieved in a non-invasive manner. BL has great promise as a highly desirable biosensor for studying organ-on-chip platforms.</p