The next generation of giant-segmented mirror telescopes (> 20 m) will enable us to observe galactic nuclei at much higher angular resolution and sensitivity than ever before. These capabilities will introduce a revolutionary shift in our understanding of the origin and evolution of supermassive black holes by enabling more precise black hole mass measurements in a mass range that is unreachable today. We present simulations and predictions of the observations of nuclei that will be made with the Thirty Meter Telescope (TMT) and the adaptive optics assisted integral-field spectrograph IRIS, which is capable of diffraction-limited spectroscopy from Z band (0.9 µm) to K band (2.2 µm). These simulations, for the first time, use realistic values for the sky, telescope, adaptive optics system, and instrument, to determine the expected signal-to-noise ratio of a range of possible targets spanning intermediate mass black holes of ∼ 10 4 M ⊙ to the most massive black holes known today of > 10 10 M ⊙ . We find that IRIS will be able to observe Milky Way-mass black holes out the distance of the Virgo cluster, and will allow us to observe many more brightest cluster galaxies where the most massive black holes are thought to reside. We also evaluate how well the kinematic moments of the velocity distributions can be constrained at the different spectral resolutions and plate scales designed for IRIS. We find that a spectral resolution of ∼ 8000 will be necessary to measure the masses of intermediate mass black holes. By simulating the observations of galaxies found in SDSS DR7, we find that over 10 5 massive black holes will be observable at distances between 0.005 < z < 0.18 with the estimated sensitivity and angular resolution provided by access to Z-band (0.9 µm) spectroscopy from IRIS and the TMT adaptive optics system. These observations will provide the most accurate dynamical measurements of black hole masses to enable the study of the demography of massive black holes, address the origin of the M BH − σ and M BH − L relationships, and evolution of black holes through cosmic time.
The slope detection and ranging (SLODAR) method recovers atmospheric turbulence profiles from time averaged spatial cross correlations of wavefront slopes measured by Shack-Hartmann wavefront sensors. The Palomar multiple guide star unit (MGSU) was set up to test tomographic multiple guide star adaptive optics and provided an ideal test bed for SLODAR turbulence altitude profiling. We present the data reduction methods and SLODAR results from MGSU observations made in 2006. Wind profiling is also performed using delayed wavefront cross correlations along with SLODAR analysis. The wind profiling analysis is shown to improve the height resolution of the SLODAR method and in addition gives the wind velocities of the turbulent layers.
Bacterial resistance is one of the very severe factors that threaten human health. It is of great significance to construct a simple, highly effective, biocompatible, and cost-efficient therapeutic route. In this paper, a new method was constructed to prepare cationic nanoparticles, and fluorescent conjugated polymer coassembly nanoparticles CA-CPNs were designed and synthesized on the basis of the model conjugated polymers, PFVBT, and the model quarternary ammonium salts, cationic surfactant cetyltrimethylammonium bromide CTAB. PFVBTs were designed and synthesized in only three steps. CTAB is commercially available. By the reprecipitation method, the PFVBTs form the core and CTAB forms a shell on the surface of CA-CPNs by hydrophobic interaction. Importantly, when incubated with bacteria, the positively charged CA-CPNs can combine with bacteria, physically destroy the bacterial membrane, and kill bacteria without the requirement of light or chemical energy. When 0.80 μg/mL CA-CPNs were incubated for 30 min with Escherichia coli, more than 91% bacteria were killed. Also, more than 96% Staphylococcus aureus were dead when incubated with 1.0 μg/mL CA-CPNs. In virtue of the bright red fluorescence, CA-CPNs were also successfully applied to image MCF-7 cell with good biocompatibility. Overall, a simple, cost-effective, and universal method was provided to prepare cationic fluorescent nanoparticles that are a promising nanomaterial for biomedical applications.
NFIRAOS, the Thirty Meter Telescope's first adaptive optics system is an order 60x60 Multi-Conjugate AO system with two deformable mirrors. Although most observing will use 6 laser guide stars, it also has an NGS-only mode. Uniquely, NFIRAOS is cooled to -30 °C to reduce thermal background. NFIRAOS delivers a 2-arcminute beam to three client instruments, and relies on up to three IR WFSs in each instrument. We present recent work including: robust automated acquisition on these IR WFSs; trade-off studies for a common-size of deformable mirror; real-time computing architectures; simplified designs for high-order NGS-mode wavefront sensing; modest upgrade concepts for highcontrast imaging.
We describe a high fidelity simulation method for estimating the sky coverage of multiconjugate adaptive optics systems; this method is based upon the split tomography control architecture, and employs an AO simulation postprocessing technique to evaluate system performance with hundreds of randomly generated natural guide star (NGS) asterisms. A novel technique to model the impact of quadratic wavefront aberrations upon the NGS point spread functions is described; this is used to model the variations in system performance with different asterisms, and is crucial for obtaining accurate results with the postprocessing technique. Several design and algorithm improvements help to reduce the residual wavefront error in the tip/tilt and plate scale modes that are controlled using the NGS asterism. These improvements include choosing the right wavefront sensor (WFS) pixel size, optimal pixel weights, and type II control of the plate scale modes.
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