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We assemble a sample of 696 type 1 AGN up to a redshift of $z=2.5$, all of which have an SDSS spectrum containing at least one broad emission line (H $\alpha$, H $\beta$ or Mg II) and an XMM-Newton X-ray spectrum containing at least 250 counts in addition to simultaneous optical/ultraviolet photometry from the XMM Optical Monitor. Our sample includes quasars and narrow-line Seyfert 1s: thus our AGN span a wide range in luminosity, black hole mass and accretion rate. We determine single-epoch black hole mass relations for the three emission lines and find that they provide broadly consistent mass estimates whether the continuum or emission line luminosity is used as the proxy for the broad emission line region radius. We explore variations of the UV/X-ray energy index $\alpha_\mathrm{ox}$ with the UV continuum luminosity and with black hole mass and accretion rate, and make comparisons to the physical quasar spectral energy distribution (SED) model QSOSED. The majority of the AGN in our sample lie in a region of parameter space with $0.02, Comment: 23 pages, 24 figures and 10 tables. Accepted for publication in MNRAS

We present reverberation mapping measurements for the prominent ultraviolet broad emission lines of the active galactic nucleus Mrk817 using 165 spectra obtained with the Cosmic Origins Spectrograph on the Hubble Space Telescope. Our ultraviolet observations are accompanied by X-ray, optical, and near-infrared observations as part of the AGN Space Telescope and Optical Reverberation Mapping Program 2 (AGN STORM 2). Using the cross-correlation lag analysis method, we find significant correlated variations in the continuum and emission-line light curves. We measure rest-frame delayed responses between the far-ultraviolet continuum at 1180 A and Ly$\alpha$ $\lambda1215$ A ($10.4_{-1.4}^{+1.6}$ days), N V $\lambda1240$ A ($15.5_{-4.8}^{+1.0}$days), SiIV + OIV] $\lambda1397$ A ($8.2_{-1.4}^{+1.4}$ days), CIV $\lambda1549$ A ($11.8_{-2.8}^{+3.0}$ days), and HeII $\lambda1640$ A ($9.0_{-1.9}^{+4.5}$ days) using segments of the emission-line profile that are unaffected by absorption and blending, which results in sampling different velocity ranges for each line. However, we find that the emission-line responses to continuum variations are more complex than a simple smoothed, shifted, and scaled version of the continuum light curve. We also measure velocity-resolved lags for the Ly$\alpha$, and CIV emission lines. The lag profile in the blue wing of Ly$\alpha$ is consistent with virial motion, with longer lags dominating at lower velocities, and shorter lags at higher velocities. The CIV lag profile shows the signature of a thick rotating disk, with the shortest lags in the wings, local peaks at $\pm$ 1500 $\rm km\,s^{-1}$, and a local minimum at line center. The other emission lines are dominated by broad absorption lines and blending with adjacent emission lines. These require detailed models, and will be presented in future work., Comment: Submitted to ApJ. 25 pages, 8 figures, and 6 tables

The desire for thin-film silicon is motivated by the growing needs for flexible electronics, compact packaging, and advanced solar power. In previous work we have presented exfoliation as means to a cost effective way to achieve thin-film silicon and described an open loop prototype exfoliation tool that could be used to produce improved films compared to previous methods. However, controllable film thickness, film uniformity, and surface roughness were all challenges with the open loop setup. This paper describes the design, construction, and testing of an improved controlled exfoliation tool with load compensation and inline metrology for closed loop control of the exfoliation process. The exfoliation performance results are compared to those from the proof-of-concept tool and show 53% improvement in silicon uniformity and 67% improvement in average surface roughness. These improvements can be attributed to the addition of load compensation and the improvement in the precision motion of the stage, respectively.

We present the first intensive study of the variability of the near-infrared coronal lines in an active galactic nucleus (AGN). We use data from a one-year long spectroscopic monitoring campaign with roughly weekly cadence on NGC 5548 to study the variability in both emission line fluxes and profile shapes. We find that in common with many AGN coronal lines, those studied here are both broader than the low-ionisaton forbidden lines and blueshifted relative to them, with a stratification that implies an origin in an outflow interior to the standard narrow line region. We observe for the first time [S VIII] and [Si VI] coronal line profiles that exhibit broad wings in addition to narrow cores, features not seen in either [S IX] or [Si X]. These wings are highly variable, whereas the cores show negligible changes. The differences in both the profile shapes and variability properties of the different line components indicate that there are at least two coronal line regions in AGN. We associate the variable, broad wings with the base of an X-ray heated wind evaporated from the inner edge of the dusty torus. The coronal line cores may be formed at several locations interior to the narrow line region: either along this accelerating, clumpy wind or in the much more compact outflow identified with the obscurer and so emerging on scales similar to the outer accretion disc and broad line region., 20 pages, 16 figures and 6 tables. Accepted for publication in MNRAS

The direct exfoliation of thin films from silicon wafers has the potential to significantly lower the cost of flexible electronics while leveraging the performance benefits and established infrastructure of traditional wafer-based fabrication processes. However, controlling the thickness and uniformity of exfoliated silicon thin films has proven difficult due to a lack of understanding and control over the exfoliation process. This paper presents a new silicon exfoliation process and model which enables accurate prediction of the thickness and quality of the exfoliated thin-film based on the exfoliation process parameters. This model uses a parametric, finite element, linear elastic fracture mechanics study with nonlinear loading to determine how each process parameter affects the crack propagation depth. A metamodel is then constructed from the results of numerous simulations to inform the design and operation of a novel exfoliation tool and predict thickness of produced films. In order to manufacture uniform, high-quality films, the tool creates a controlled peeling load that is able to propagate a crack through the silicon in a controlled manner. Finally, exfoliated silicon samples produced with the prototype tool are evaluated and compared to metamodel projections, confirming the ability of the tool to steer crack trajectory within ± 3 microns of the crack depth predictions.

In this paper, we present a simple strategy to identify Non-Terrestrial artefacts \citep[NTAs;][]{Kopparapu} in or near geosynchronous Earth orbits (GEOs). We show that even the small pieces of reflective debris in orbit around the Earth can be identified through searches for multiple transients in old photographic plate material exposed before the launch of first human satellite in 1957. In order to separate between possible false point-like sources on photographic plates from real reflections, we present calculations to quantify the associated probabilities of alignments. We show that in an image with nine "simultaneous transients" at least four or five point sources along a line within a $10 \ast 10$ arcmin$^{2}$ image box are a strong indicator of NTAs, corresponding to significance levels of $2.5$ to $3.9 \sigma$. This given methodology can then be applied to set an upper limit to the prevalence of NTAs with reflective surfaces in geosynchronous orbits., Comment: Accepted into Acta Astronautica

We mathematically model, fabricate, and test a counter-gravity heat pipe with a unique header and artery system. The header and artery system augments the capillary limit of traditional heat pipes with homogeneous wicks by incorporating a low resistance pathway for liquid return from the condenser to the evaporator. Unlike other composite wick designs for low resistance liquid return to the evaporator, the header and artery system enables priming of the wick structure for counter-gravity start-up. We tested a stainless steel-water heat pipe with the header and artery system. This header and artery heat pipe demonstrated reliable counter-gravity start-up with a capillary limit augmentation of over four times that of the same heat pipe with a conventional homogeneous wick. This result is in agreement with a theory developed by Chisholm (1978).

As the cost and complexity of equipment used in fields such as aerospace and defense has increased, so has the value of methods known as nondestructive evaluation (NDE), which can detect faults without damaging or disassembling the equipment. Air bearing spin-down testing is a form of NDE that detects minute amounts of damage by rotating the entire assembly and measuring energy dissipation as it decelerates. While this method is highly sensitive to determining the existence of damage, it cannot determine the location or type of the damage. The proposed method merges spin-down testing with vibro-acoustic modulation (VAM) to locate simulated damage in a test piece mounted on a test bed featuring conventional rolling bearings and an electric motor to control the spin-down rate. VAM utilizes a high-frequency probing signal modulated by a low-frequency pumping signal to excite non-linearities caused by damage. In this case, the pumping signal is provided by the rotation of the sample and the resulting gravitational and inertial forces. A piezoelectric actuator provides the probing signal and an acoustic emission sensor detects variations in the signal response. This work explores combining acoustic, angular velocity and position signal analysis to locate the source of the damage.

Research arguing that performance on a test of professional competency may reflect a teacher candidate's overall analytical and reading abilities has led many Colleges of Education (COEs) to require the assessment of reading competence for admission into a teacher preparation program. This is true in Texas where COEs are held accountable for the success rates of their program completers on the Texas Examination of Educator Standards and Pedagogy and Professional Responsibilities (TExES PPR). This study explores the relationship between performance scores on the reading portion of the Texas Higher Education Assessment and the professional qualifications of teachers as measured by TExES PPR. Findings suggest that reading scores may explain 30% to 35% of the variance in scores on the existing licensure exam in Texas.

A collaborative endeavor between Texas A&M University–Corpus Christi and Miller High School resulted in the Cyberways and Waterways Family Project, a unique partnership of educators, families and high school students. University and high school faculty engaged ninth grade biology students and their parents in water testing of Corpus Christi Bay, while the younger siblings participated in an on–site “writer's camp.” The families' shared learning experiences were recorded in PowerPoint presentations produced by the parents and students. The project created new school–university networks and will serve as a springboard for future collaborative action research.

The era of 8 meter class telescopes will naturally have a major impact on the study of AGN. In this review I focus on the promise of diffraction limited observations in the near and mid-infrared regions. An important pillar supporting the currently popular unified model for AGN, is the existence of a dusty molecular torus. The so-called AGN-starburst connection, is another area of intensive study. High spatial resolution observations with the VLT will observationally quantify the properties of these components.

I review the methods used to discover obscured AGN. These are; optical and near infrared spectroscopic searches for broad wings on permitted lines, analysis of the X‐ray continuum distribution, and optical spectropolarimetry which can reveal the scattered component of the BLR and non stellar continuum. New optical and X‐ray observations of the narrow‐line radio galaxy (NLRG) IC 5063, show it to be an obscured BLRG.

The continua of type 1 Seyferts from 0.3 to 100 microns have been examined. We focus on the modifying effects of dust, both in terms of absorption and re-radiation. After allowance is made for dust and the presence of extranuclear contributions to the IRAS fluxes, there remains a ubiquitous underlying distribution which we believe to be non-thermal. There is evidence that the thermal infrared components corresponding to hot and warm dust may be associated with the broad and narrow emission line regions.