We present Advanced Camera for Surveys, NICMOS, and Keck adaptive-optics-assisted photometry of 20 Type Ia supernovae (SNe Ia) from the Hubble Space Telescope (HST) Cluster Supernova Survey. The SNe Ia were discovered over the redshift interval 0.623 1 SNe Ia. We describe how such a sample could be efficiently obtained by targeting cluster fields with WFC3 on board HST. The updated supernova Union2.1 compilation of 580 SNe is available at http://supernova.lbl.gov/Union.

/pdf/the-hubble-space-telescope-cluster-supernova-survey-v-2zmug8844k.pdf

The Hubble Space Telescope Cluster Supernova Survey. V. Improving the Dark-energy Constraints above z > 1 and Building an Early-type-hosted Supernova Sample

The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST's special design allows both a large aperture (effective aperture of 3.6 m–4.9 m) and a wide field of view (FOV) (5°). It has an innovative active reflecting Schmidt configuration which continuously changes the mirror's surface that adjusts during the observation process and combines thin deformable mirror active optics with segmented active optics. Its primary mirror (6.67 m × 6.05 m) and active Schmidt mirror (5.74m × 4.40m) are both segmented, and composed of 37 and 24 hexagonal sub-mirrors respectively. By using a parallel controllable fiber positioning technique, the focal surface of 1.75 m in diameter can accommodate 4000 optical fibers. Also, LAMOST has 16 spectrographs with 32 CCD cameras. LAMOST will be the telescope with the highest rate of spectral acquisition. As a national large scientific project, the LAMOST project was formally proposed in 1996, and approved by the Chinese government in 1997. The construction started in 2001, was completed in 2008 and passed the official acceptance in June 2009. The LAMOST pilot survey was started in October 2011 and the spectroscopic survey will launch in September 2012. Up to now, LAMOST has released more than 480000 spectra of objects. LAMOST will make an important contribution to the study of the large-scale structure of the Universe, structure and evolution of the Galaxy, and cross-identification of multi-waveband properties in celestial objects.

https://iopscience.iop.org/article/10.1088/1674-4527/12/9/003/pdf

The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST)

We report data for I-band surface brightness fluctuation (SBF) magnitudes, (V-I) colors, and distance moduli for 300 galaxies. The survey contains E, S0, and early-type spiral galaxies in the proportions of 49 : 42 : 9 and is essentially complete for E galaxies to Hubble velocities of 2000 km s-1, with a substantial sampling of E galaxies out to 4000 km s-1. The median error in distance modulus is 0.22 mag. We also present two new results from the survey. (1) We compare the mean peculiar flow velocity (bulk flow) implied by our distances with predictions of typical cold dark matter transfer functions as a function of scale, and we find very good agreement with cold, dark matter cosmologies if the transfer function scale parameter Γ and the power spectrum normalization σ8 are related by σ8Γ-0.5 ≈ 2 ± 0.5. Derived directly from velocities, this result is independent of the distribution of galaxies or models for biasing. This modest bulk flow contradicts reports of large-scale, large-amplitude flows in the ~200 Mpc diameter volume surrounding our survey volume. (2) We present a distance-independent measure of absolute galaxy luminosity, and show how it correlates with galaxy properties such as color and velocity dispersion, demonstrating its utility for measuring galaxy distances through large and unknown extinction.

https://iopscience.iop.org/article/10.1086/318301/pdf

The SBF Survey of Galaxy Distances. IV. SBF Magnitudes, Colors, and Distances

We present the photometric calibration of the Advanced Camera for Surveys (ACS). The ACS was installed in the Hubble Space Telescope (HST) in 2002 March. It comprises three cameras: the Wide Field Channel (WFC), optimized for deep near‐IR survey imaging programs; the High Resolution Channel (HRC), a high‐resolution imager that fully samples the HST point‐spread function (PSF) in the visible; and the Solar Blind Channel (SBC), a far‐UV imager. A significant amount of data has been collected to characterize the on‐orbit performance of the three channels. We give here an overview of the performance and calibration of the two CCD cameras (WFC and HRC) and a description of the best techniques for reducing ACS CCD data. The overall performance is as expected from prelaunch testing of the camera. Surprises were a better‐than‐predicted sensitivity in the visible and near‐IR for both the WFC and HRC and an unpredicted dip in the HRC UV response at ∼3200 A. On‐orbit observations of spectrophotometric stand...

https://iopscience.iop.org/article/10.1086/444553/pdf

The photometric performance and calibration of the Hubble Space Telescope advanced camera for surveys

A Three Dimensional Structure (3DS) Memory (100) allows for physical separation of the memory circuits (103) and the control logic circuit (101) onto different layers (103) such that each layer may be separately optimized. One control logic circuit (101) suffices for several memory circuits (103), reducing cost. Fabrication of 3DS memory (100) involves thinning of the memory circuit (103) to less than 50 microns in thickness and bonding the circuit to a circuit stack while still in wafer substrate form. Fine-grain high density inter-layer vertical bus connections (105) are used. The 3DS memory (100) manufacturing method enables several performance and physical size efficiencies, and is implemented with established semiconductor processing techniques.

Three dimensional structure memory

This article explores the phenomenon of dark current random telegraph signal (DC-RTS) noise in commercial off-the-shelf CMOS image sensors. Five sensors were irradiated with high-energy photons to a variety of doses and analyzed with a wavelet-based signal reconstruction algorithm. The algorithm is explained in detail and the radiation effects on individual pixels are discussed. Finally, the production rate of RTS pixels as a function of dose is explored, providing information on the underlying defect structure responsible for this noise source.

Wavelet Analysis of RTS Noise in CMOS Image Sensors Irradiated With High-Energy Photons

In earlier work, a model of the back illuminated CCD was presented and used to predict optical quantum efficiency. In this work we expand on the model and find an analytical solution for the probability of collection of a carrier generated at a given depth. We apply our solution to find the theoretical quantum efficiencies for both electron bombardment and optical illumination and compare them to measurements taken on thinned, backside-enhanced, non- AR coated devices. A single set of parameters is found which shows a reasonable fit to both sets of data. Earlier models of electron-bombarded CCDs have failed to explain the measured nonzero gain at low energies, however our model shows nonzero gain at all energies.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Simple model of electron-bombarded CCD gain

of EP0314334An intergrated circuit formed in a semiconductor die which has at least two distinct functional regions is treated by mounting the die by way of its front face on a support member, and subsequently removing die material by way of its back face so as to physically separate the functional regions of the die from each other. The optically opaque dielectric material (66) is optional.

Isolation of a charge coupled device

Within a pixel in a digital imager, generally either a charge- coupled device or complementary metal oxide semiconductor device, doping of the semiconductor substrate and application of gate vol- tages create a region free of mobile carriers called the depletion region. This region fills with charge after incoming photons or thermal energy raise the charges from the valence to the conduction energy band. As the signal charge fills the depletion region, the electric field generating the region is altered, and the size of the region is reduced. We present a model that describes how this dynamic depletion region, along with the location of impurities, will result in pixels that produce less dark current after being exposed to light and additionally show nonlinear production rates with respect to exposure time. These types of effects have been observed in digital imagers, allowing us to compare empirical data with the modeled data. © 2012 SPIE and IS&T. (DOI: 10.1117/1.JEI.21.4.043011)

/pdf/dark-current-modeling-with-a-moving-depletion-edge-53ntm3itu5.pdf

Dark current modeling with a moving depletion edge

The dark current that arises due to diffusion from the bulk is assuming a more important role now that
CCD and CMOS image sensors have found their way into consumer electronics which must be capable
of operating at elevated temperatures. Historically this component has been estimated from the
diffusion related current of a diode with an infinite substrate. This paper explores the effect of a
substrate of finite extent beneath the collecting volume of the pixel for a front-illuminated device and
develops a corrected expression for the diffusion related dark current. The models show that the
diffusion dark current can be much less than that predicted by the standard model.

Diffusion dark current in front-illuminated CCDs and CMOS image sensors

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