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We present the early UV and optical light curve of Type IIP supernova (SN) 2010aq at z=0.0862, and compare it to analytical models for thermal emission following SN shock breakout in a red supergiant star. SN 2010aq was discovered in joint monitoring between the Galaxy Evolution Explorer (GALEX) Time Domain Survey (TDS) in the NUV and the Pan-STARRS1 Medium Deep Survey (PS1 MDS) in the g, r, i, and z bands. The GALEX and Pan-STARRS1 observations detect the SN less than 1 day after shock breakout, measure a diluted blackbody temperature of 31,000 +/- 6,000 K 1 day later, and follow the rise in the UV/optical light curve over the next 2 days caused by the expansion and cooling of the SN ejecta. The high signal-to-noise ratio of the simultaneous UV and optical photometry allows us to fit for a progenitor star radius of 700 +/- 200 R_sun, the size of a red supergiant star. An excess in UV emission two weeks after shock breakout compared to SNe well fitted by model atmosphere-code synthetic spectra with solar metallicity, is best explained by suppressed line blanketing due to a lower metallicity progenitor star in SN 2010aq. Continued monitoring of PS1 MDS fields by the GALEX TDS will increase the sample of early UV detections of Type II SNe by an order of magnitude, and probe the diversity of SN progenitor star properties., 4 pages, 3 color figures. Accepted for publication in ApJ Letters, corrections from proofs added

Growth of Hg1−xCdxTe by molecular beam epitaxy (MBE) has been under development since the early 1980s at Rockwell Scientific Company (RSC), formerly the Rockwell Science Center; and we have shown that high-performance and highly reproducible MBE HgCdTe double heterostructure planar p-on-n devices can be produced with high throughput for various single- and multiplecolor infrared applications. In this paper, we present data on Hg1−xCdxTe epitaxial layers grown in a ten-inch production MBE system. For growth of HgCdTe, standard effusion cells containing CdTe and Te were used, in addition to a Hg source. The system is equipped with reflection high energy electron diffraction (RHEED) and spectral ellipsometry in addition to other fully automated electrical and optical monitoring systems. The HgCdTe heterostructures grown in our large ten-inch Riber 49 MBE system have outstanding structural characteristics with etch-pit densities (EPDs) in the low 104 cm−2 range, Hall carrier concentration in low 1014 cm−3, and void density

We present a weak lensing and photometric study of six half by half degree fields observed at the CFHT using the UH8K CCD mosaic camera. The fields were observed for a total of 2 hours each in I and V, resulting in catalogs containing ~ 20 000 galaxies per passband per field. We use V-I color and I magnitude to select bright early type galaxies at redshifts 0.1 < z < 0.9. We measure the gravitational shear from faint galaxies in the range 21 < m_I < 25 from a composite catalog and find a strong correlation with that predicted from the early types if they trace the mass with mass-to-light ratio 300\pm75 h (in solar units) for a flat (Omega_m0 = 0.3, Omega_l0 = 0.7) lambda cosmology and 400\pm100 h for Einstein-de Sitter. We make two-dimensional reconstructions of the mass surface density. Cross-correlation of the measured mass surface density with that predicted from the early type galaxy distribution shows a strong peak at zero lag (significant at the 5.2-sigma level). We azimuthally average the cross- and auto-correlation functions. We conclude that the profiles are consistent with early type galaxies tracing mass on scales of > 45 arcsec (> 200 kpc at z = 0.5). We sub-divide our bright early type galaxies by redshift and obtain similar conclusions. These mass-to-light ratios imply ��_m0 = 0.10\pm0.02 (��_m0 = 0.13\pm0.03 for Einstein-de Sitter) of closure density., 27 pages, 19 figs (4 ps, 15 gif), 4 tables, accepted for publication in Ap.J. (email Gillian for better resolution ps versions of gif greyscale plots)

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, with a substantial sampling of E galaxies out to 4000 km/s. 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 find very good agreement with cold, dark matter cosmologies if the transfer function scale parameter $\Gamma$, and the power spectrum normalization $\sigma_8$ are related by $\sigma_8 \Gamma^{-0.5} \approx 2\pm0.5$. Derived directly from velocities, this result is independent of the distribution of galaxies or models for biasing. The modest bulk flow contradicts reports of large-scale, large-amplitude flows in the $\sim200$ Mpc diameter volume surrounding our Survey volume. (2) We present a distance-independent measure of absolute galaxy luminosity, \Nbar, 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., Comment: Accepted for publication in ApJ (10 January 2001); 23 pages

Using a new f/31 secondary on a tip-tilt platform, we have built an image-stabilization system which has been used regularly for astronomical imaging and spectroscopy on the University of Hawaii 2.2 m telescope. Diffraction-limited cores of stellar point-spread functions are achieved in near-infrared imaging, with Strehl ratios as high as 0.47. K-band images with 03 FWHM resolution (without deconvolution) are routinely obtained. The construction, operation, and capability of the current system are described, a summary of recent scientific findings is presented, and future improvements are outlined.

Surface brightness fluctuations (SBFs) are much brighter in the IR than they are at optical wavelengths, making it possible to measure greater distances using IR SBFs. We report new K' (2.1 micron) SBF measurements of 9 galaxies in the Fornax and Eridanus clusters using a 1024^2-pixel HgCdTe array. We used improved analysis techniques to remove contributions from globular clusters and background galaxies, and we assess the relative importance of other sources of residual variance. We applied the improved methodology to Fornax and Eridanus images and to previously published Virgo cluster data. Apparent fluctuation magnitudes were used in conjunction with Cepheid distances to M31 and the Virgo cluster to calibrate the K' SBF distance scale. We find the absolute fluctuation magnitude MK'= -5.61+/-0.12, with an intrinsic scatter to the calibration of 0.06 mag. No statistically significant change in MK' is detected as a function of (V-I). Our calibration is consistent with constant age and metallicity stellar population models. The lack of a correlation with (V-I) in the context of the stellar population models implies that elliptical galaxies bluer than (V-I)=1.2 have SBFs dominated by younger (5-8 Gyr) populations. K' SBFs prove to be a reliable distance indicator as long as the residual variance from globular clusters and background galaxies is properly removed. Also, it is important that a sufficiently high S/N ratio be achieved to allow reliable sky subtraction because residual spatial variance can bias the measurement of the SBF power spectrum. (abridged), Accepted for publication in ApJ, 44 pages, 10 Postscript figures

In this paper, we report on the morphologically segregated I- and K-band number counts at bright magnitudes from a wide-field deep survey. This survey has been carried out with the first large mosaic CCD camera (8192 × 8192) on the University of Hawaii 88 inch (2.24 m) telescope and the Canada-France-Hawaii Telescope (CFHT). This instrument allows us to take deep wide-field galaxy images efficiently. We have been able to obtain I-band number counts in a wide range from I = 12.5 to I = 22.5, and to classify the morphologies of galaxies down to I = 18.5. Morphologically segregated number counts for ellipticals, spirals, and irregulars are obtained for the first time with magnitudes brighter than I = 18.5. The morphological classifications correlate well with the galaxy colors. By modeling these number counts, we confirm that a no-evolution model can fit both K- and I-band number counts of ellipticals and spirals reasonably well, but the irregular/peculiar galaxies show a substantial excess at faint magnitudes over the no-evolution model. With the number counts at bright magnitudes, we further demonstrate that the rise in this excess begins by I = 20. This rise is consistent with a rapidly increasing star formation rate in low-luminosity galaxies at about z = 0.35.

Teledyne’s silicon hybrid CMOS focal plane array technology has matured into a viable, high performance and high- TRL alternative to scientific CCD sensors for space-based applications in the UV-visible-NIR wavelengths. This paper presents the latest results from Teledyne’s low noise silicon hybrid CMOS visible focal place array produced in 4K×4K format with 10 μm pixel pitch. The H4RG-10 readout circuit retains all of the CMOS functionality (windowing, guide mode, reference pixels) and heritage of its highly successful predecessor (H2RG) developed for JWST, with additional features for improved performance. Combined with a silicon PIN detector layer, this technology is termed HyViSI™ (Hybrid Visible Silicon Imager). H4RG-10 HyViSI™ arrays achieve high pixel interconnectivity (

In preparation for the large number of infrared pixels required in the era of Extremely Large Telescopes, Teledyne, in partnership with the University of Hawaii and GL Scientific, has been funded to develop the next generation of largeformat infrared focal plane array for ground-based astronomy; the 4096 × 4096 pixel (15 micron pitch) H4RG-15. Teledyne has successfully designed, produced, and tested the first generation H4RG-15 prototype arrays. This paper reports on the functionality and performance test results of the H4RG-15 prototypes and provides status of the 2012 pilot production effort.

Teledyne’s H2RG focal plane arrays have been widely used in scientific infrared and visible instruments for ground-based and space-based telescopes. The majority of applications use the H2RG with 2.5 micron cutoff HgCdTe detector pixel at an operating temperature of ~77 K (LN2). The exceptionally low dark current of the 2.5 micron H2RG allows for operation at higher temperatures which facilitates simplified instrument designs and therefore lower instrument cost. Performance data of 2.5 micron H2RG arrays at 77K, 100 K, and 120 K are presented and are discussed as a function of detector bias and pixel readout rate. This paper also presents performance data of 1.75 micron and 5.3 micron H2RG focal plane arrays and discusses some of the inherent performance differences compared to 2.5 micron cutoff arrays. A complete infrared camera system that uses the H2RG focal plane array and SIDECAR ASIC focal plane electronics is introduced.

The primary goal of the HAWAII 4RG-15 (H4RG-15) development is to provide a 16 megapixel 4096x4096 format at significantly reduced price per pixel while maintaining the superb low background performance of the HAWAII 2RG (H2RG). The H4RG-15 design incorporates several new features, notably clocked reference output and interleaved reference pixel readout, that promise to significantly improve noise performance while the reduction in pixel pitch from 18 to 15 microns should improve transimpedance gain although at the expense of some degradation in full well and crosstalk. During the Phase-1 development, Teledyne has produced and screen tested six hybrid arrays. In preparation for Phase-2, the most promising of these are being extensively characterized in the University of Hawaii’s (UH) ULBCam test facility originally developed for the JWST H2RG program. The end-to-end performance of the most promising array has been directly established through astronomical imaging observations at the UH 88-inch telescope on Mauna Kea. We report the performance of these Phase-1 H4RG-15s within the context of established H2RG performance for key parameters (primarily CDS read noise), also highlighting the improvements from the new readout modes.

We report on the final design and current status of a 1-5 micron infrared test bench at the ETH Zurich Institute for Astronomy. This facility will enable us to characterize infrared optics, both reflective and transmissive, at cryogenic operating temperatures for both ground- and space-based applications. A focus of our lab is to facilitate the detection and characterization of extra-solar planets. The test bench is designed to characterize a range of spectrally dispersive and diffraction suppression optics such as filters, grisms, gratings, as well as both focal and pupil plane coronagraphs. The test bench is built around a 2048x2048 HAWAII-2RG detector from Teledyne Imaging Systems. The optical bench is envisioned to operate down to 30 K. “First light” is expected in the second half of 2012. We outline the status of the project, and describe the capabilities of the test bench in detail in order to alert potential collaborators to this new capability.

We present grism spectra of emission-line galaxies (ELGs) from 0.6-1.6 microns from the Wide Field Camera 3 on the Hubble Space Telescope. These new infrared grism data augment previous optical Advanced Camera for Surveys G800L 0.6-0.95 micron grism data in GOODS-South from the PEARS program, extending the wavelength covereage well past the G800L red cutoff. The ERS grism field was observed at a depth of 2 orbits per grism, yielding spectra of hundreds of faint objects, a subset of which are presented here. ELGs are studied via the Ha, [OIII], and [OII] emission lines detected in the redshift ranges 0.22., Comment: Accepted for publication in AJ. Updated to include referee comments. Updated sample using improved reduction contains 23 new galaxies (Table 1; Figures 2 & 3)

The Orthogonal Transfer Array (OTA) is a monolithic array of small CCDs that are 4-side buttable and can be mosaicked to make the 40K×40K focal plane required by Pan-STARRS. These devices have other interesting properties such as a 'Deep Depletion' structure which enables 75 µm thick devices to be fully depleted with modest charge diffusion, while offering 35 % QE at 1 µm. Pan-STARRS has evaluated OTAs from a test lot, and is now fabricating the first two production lots. We expect to deploy the first of four cameras in June 2006.

The Pan-STARRS project will undertake repeated surveys of the sky, finding "Killer Asteroids" and everything which moves or blinks, as well as building an unprecedentedly deep and accurate image of the sky. The key technology for this is the next generation of large format cameras, which will offer an order of magnitude improvement in size, speed, and cost relative to existing instruments. This is achieved in part by the integrated design of telescope, detectors, controllers, software, and scientific direction.

The orthogonal-transfer array (OTA) is a new charge-coupled device (CCD) concept for wide-field imaging in groundbased astronomy based on the orthogonal-transfer CCD (OTCCD). This device combines an 8×8 array of small OTCCDs, each about 600×600 pixels with on-chip logic to provide independent control and readout of each CCD. The device provides spatially varying electronic tip-tilt correction for wavefront aberrations, as well as compensation for telescope shake. Tests of prototype devices have verified correct functioning of the control logic and demonstrated good CCD charge-transfer efficiency and high quantum efficiency. Independent biasing of the substrate down to -40 V has enabled fully depleted operation of 75-μm-thick devices with good charge PSF. Spurious charge or "glow" due to impact ionization from high fields at the drains of some of the NMOS logic FETs has been observed, and reprocessing of some devices from the first lot has resolved this issue. Read noise levels have been 10 - 20 e-, higher than our goal of 5 e-, but we have identified the likely sources of the problem. A second design is currently in fabrication and uses a 10-μm pixel design resulting in a 22.6-Mpixel device measuring 50×50 mm. These devices will be deployed in the U. of Hawaii Pan-STARRS focal plane, which will comprise 60 OTAs with a total of nearly 1.4 Gpixels.

The University of Hawaii Wide-Field Imager (UHWFI) is a focal compressor system designed to project the full half-degree field of the UH 2.2 m telescope onto the refurbished UH 8Kx8K CCD camera. The optics use Ohara glasses and are mounted in an oil-filled cell to minimize light losses and ghost images from the large number of internal lens surfaces. The UHWFI is equipped with a six-position filter wheel and a rotating sector blade shutter,both driven by stepper motors. The instrument saw first light in 2004 in an engineering mode. After filling the lens cell with index matching oil, integration of all software components into the user interface, tuning of the CCD performance, and the purchase of the final filter set, UHWFI is now fully commissioned at the UH 2.2 m telescope., Comment: 13 pages of text, 2 tables, 8 figures

WIRCam (Wide-field InfraRed Camera) is a near-infrared (0.9-2.4 microns) camera developed for the prime focus of the Canada France Hawaii Telescope (CFHT), a 3.6-m telescope located on Mauna Kea, Hawaii. WIRCam is based on 4 x 2048x2048 HAWAII2RG arrays, developed by Rockwell. The camera provides a 0.3"/pixel sampling, and the close packaging of the detectors allows to cover an almost contiguous field-of-view of 20.5' x 20.5'. All optical elements are assembled in a cryovessel and cooled down to 85K by a He closed cycle cryogenerator. The two filter wheels have capacity for 8 filters (110 mm in diameter), cooled at low temperature together with the Lyot stop. These wheels are mounted on sapphire ball bearings and powered by external motors. Passive spring indexers define their positioning. A fused-silica tip/tilt plate powered by voice coil type motors provides image stabilization in front of the cryovessel. It compensates for flexures as well as for low frequency telescope oscillations from wind shake. This paper describes the overall architecture of the camera, giving the optical estimated performances and details some specific points of the design such as filter wheels, thermal connections, etc.

The NIRCam instrument will fly ten of Rockwell Scientific’s infrared molecular beam epitaxy HgCdTe 2048x2048 element detector arrays, each the largest available with current technology, for a total of 40 Megapixels. The instrument will have two varieties of MBE HgCdTe, a SWIR detector with λco = 2.5 μm, for the shortwave channel of NIRCam (0.6-2.3 μm); and a MWIR detector with λco = 5.3 μm, for the longwave channel of NIRCam (2.4-5.0 μm). Demonstrated mean detector dark currents less than 0.01 electrons per second per pixel at operating temperatures below 42 K for the MWIR and below 80 K for the SWIR, combined with quantum efficiency in excess of 80 percent and read noise below 6 electrons rms, make these detector arrays by far the most sensitive SWIR and MWIR devices in the world today. The unique advantages of molecular beam epitaxy as well as FPA data on noise, dark current, quantum efficiency, and other performance metrics will be discussed. In addition, the focal plane assembly package designs will be presented and discussed.

The orthogonal-transfer array (OTA) is a new CCD architecture designed to provide wide-field tip-tilt correction of astronomical images. The device consists of an 8x8 array of small (~500x500 pixels) orthogonal-transfer CCDs (OTCCD) with independent addressing and readout of each OTCCD. This approach enables an optimum tip-tilt correction to be applied independently to each OTCCD across the focal plane. The first design of this device has been carried out at MIT Lincoln Laboratory in support of the Pan-STARRS program with a collaborative parallel effort at Semiconductor Technology Associates (STA) for the WIYN Observatory. The two versions of this device are functionally compatible and share a common pinout and package. The first wafer lots are complete at Lincoln and at Dalsa and are undergoing wafer probing.

CFHT is planning to upgrade its adaptive optics system, PUEO, to a high order system with 104 elements, PUEO NUI. Currently PUEO uses a 19 element deformable mirror with the equivalent 19 avalanche photodiode (APD) detectors as its curvature wavefront sensor. PUEO NUI plans to implement the curvature wavefront sensor using back illuminated CCID-35 detectors developed by J. Beletic et al. instead of 104 APDs, which are prohibitively expensive under the present budget conditions. The CCID-35 detectors, developed at ESO and MIT/LL, were specifically designed to serve as direct replacements for APDs in curvature sensing. The first step in the upgrade is to build and test a system using two CCID-35 detectors, dubbed FlyEyes. These new detectors were successfully tested and integrated in the lab by R. Dorn at ESO but have yet to see sky time. FlyEyes will be their first opportunity. They will directly replace the 19 APDs in PUEO temporarily for a few engineering nights in January of 2005.

The PanSTARRS project has undertaken an ambitious effort to develop a completely new array controller architecture that is fundamentally driven by the large 1gigapixel, low noise, high speed OTCCD mosaic requirements as well as the size, power and weight restrictions of the PanSTARRS telescope. The result is a very small form factor next generation controller scalar building block with 1 Gigabit Ethernet interfaces that will be assembled into a system that will readout 512 outputs at ~1 Megapixel sample rates on each output. The paper will also discuss critical technology and fabrication techniques such as greater than 1MHz analog to digital converters (ADCs), multiple fast sampling and digital calculation of multiple correlated samples (DMCS), ball grid array (BGA) packaged circuits, LINUX running on embedded field programmable gate arrays (FPGAs) with hard core microprocessors for the prototype currently being developed.

We use weak lensing shear measurements of six z>0.5 clusters of galaxies to derive the mean lensing redshift of the background galaxies used to measure the shear. Five of these clusters are compared to X-ray mass models and verify a mean lensing redshift for a 23, Comment: 6 pages, 4 figures, accepted by A&A

The University of Hawaii Wide-Field Imager (UHWFI) is a focal compressor designed to project the full half-degree field of the UH 2.2m telescope onto the refurbished 8K×8K CCD camera. The optics use Ohara glasses and are mounted in an oil-filled cell to minimize light losses and ghost images from the large number of internal surfaces. The UHWFI is equipped with a six-position filter wheel and a rotating sector shutter, both driven by stepper motors. The instrument is currently in the design phase and will be commissioned early in 2003.

The Institute for Astronomy has developed and recently installed a high-resolution cross-dispersed echelle spectrograph for use at one of the coude foci of the AEOS 3.7-meter telescope, operated by the Air Force Space Command atop Mt. Haleakala on the island of Maui. The spectrograph features an optical arm for the wavelength range 0.5 - 1.0 μm and an infrared arm for the range 1.0 - 2.5 μm. We review the spectrograph design and present commissioning results obtained with both the visible and infrared arms. Both channels use a white-pupil collimator design to maximize grating efficiency and to limit the size of the camera optics. The visible arm of the spectrograph uses deep-depletion CCDs optimized for operation near 1.0 μm. The infrared detector is a 2048 x 2048 HgCdTe array (HAWAII-2) that has been developed by the Rockwell Science Center for this project. Both channels are equipped with slit-viewing cameras for object acquisition and control of a fast guiding tip-tilt mirror located at a pupil image in the spectrograph fore optics.

The Galactic Exoplanet Survey Telescope (GEST) will observe a 2 square degree field in the Galactic bulge to search for extra-solar planets using a gravitational lensing technique. This gravitational lensing technique is the only method employing currently available technology that can detect Earth-mass planets at high signal-to-noise, and can measure the frequency of terrestrial planets as a function of Galactic position. GEST's sensitivity extends down to the mass of Mars, and it can detect hundreds of terrestrial planets with semi-major axes ranging from 0.7 AU to infinity. GEST will be the first truly comprehensive survey of the Galaxy for planets like those in our own Solar System., 17 pages with 13 figures, to be published in Proc. SPIE vol 4854, "Future EUV-UV and Visible Space Astrophysics Missions and Instrumentation"

Until now, only avalanche photodiodes (APD) have been used as the detectors in curvature wavefront sensors in astronomy. This is due to the strict requirements of very short integration time and very low readout noise. In 1999, Beletic et al. invented a new CCD design which should achieve the same performance as APDs but with higher reliability and lower cost. In addition, this CCD has higher quantum efficiency than APD modules and larger dynamic range, eliminating the need for neutral density filters on bright objects. The CCD was designed and fabricated by MIT Lincoln Laboratory in collaboration with ESO and IfA. R. Dorn extensively tested the CCD in laboratory at ESO and proved that it achieves the predicted performance. CFHT is currently implementing this CCD on PUEO, CFHT’s Adaptive Optics system, to assess its performance for the first time in real conditions on the sky for a direct comparison with the current 19 APD detector system. In this article we present the current implementation scheme and discuss the upgrade we foresee for PUEO NUI, a 104-element high-order curvature AO system envisaged to replace the current AO system at Canada-France-Hawaii Telescope.

The WIYN One Degree Imager (ODI) will be a well-sampled (0.11” per pixel) imager that provides a full one degree square field of view (32K×32K pixels). ODI will utilize high resistivity, red sensitive, orthogonal transfer (OT) CCDs to provide rapid correction for image motion arising from telescope shake, guider errors, and atmospheric effects. ODI will correct the full field of view by deploying 64 array packages having a total of 4096 independently controllable OTCCDs that can correct individually for local (2 arcmin) image motion. Each array package is an orthogonal transfer array (OTA) of 64 CCDs arranged in an 8×8 grid. Each CCD has 512×512 pixels. We expect the median image quality at the WIYN 3.5m telescope in RIZ to be 0.52”, 0.43”, and 0.35” FWHM. ODI makes optimal use of the WIYN telescope, which has superb optics, excellent seeing characteristics, a natural 1.4 degree field of view (with a new corrector), and can serve as a pathfinder for LSST in terms of detectors, data pipelines, operations strategies, and scientific motivation.

The IFA and collaborators are embarking on a project to develop a 4-telescope synoptic survey instrument. While somewhat smaller than the 6.5m class telescope envisaged by the decadal review in their proposal for a LSST, this facility will nonetheless be able to accomplish many of the LSST science goals. In this paper we will describe the motivation for a 'distributed aperture' approach for the LSST, the current concept for Pan-STARRS -- a pilot project for the LSST proper -- and its performance goals and science reach. We will also discuss how the facility may be expanded.

The DEIMOS spectrograph has now been installed on the Keck-II telescope and commissioning is nearly complete. The DEEP2 Redshift Survey, which will take approximately 120 nights at the Keck Observatory over a three year period and has been designed to utilize the power of DEIMOS, began in the summer of 2002. The multiplexing power and high efficiency of DEIMOS enables us to target 1000 faint galaxies per clear night. Our goal is to gather high-quality spectra of \~60,000 galaxies with z>0.75 in order to study the properties and large scale clustering of galaxies at z ~ 1. The survey will be executed at high spectral resolution, $R=\lambda/\Delta \lambda \approx 5000$, allowing us to work between the bright OH sky emission lines and to infer linewidths for many of the target galaxies (for several thousand objects, we will obtain rotation curves as well). The linewidth data will facilitate the execution of the classical redshift-volume cosmological test, which can provide a precision measurement of the equation of state of the Universe. This talk reviews the project, summarizes our science goals and presents some early DEIMOS data., Comment: 12 pages, 5 figures, talk presented at SPIE conference, Aug. 2002

We describe progress in removing image motion over large fields of view. A camera using a new type of CCD has been commissioned and we report first results which are very promising for wide field imaging. We are embarking on a project to build a new type of astronomical CCD which should provide image motion compensation over arbitrarily large fields of view, very fast readout, autoguiding capability, good red sensitivity, and should be significantly less expensive than the present generation of CCDs.

We present measurements of the extended dark halo profiles of bright early type galaxies at redshifts 0.1 to 0.9 obtained via galaxy-galaxy lensing analysis of images taken at the CFHT using the UH8K CCD mosaic camera. Six half degree fields were observed for a total of 2 hours each in I and V, resulting in catalogs containing ~20 000 galaxies per field. We used V-I color and I magnitude to select bright early type galaxies as the lens galaxies, yielding a sample of massive lenses with fairly well determined redshifts and absolute magnitudes M ~ M_* pm 1. We paired these with faint galaxies lying at angular distances 20" to 60", corresponding to physical radii of 26 to 77 kpc (z = 0.1) and 105 to 315 kpc (z = 0.9), and computed the mean tangential shear of the faint galaxies. The shear falls off with radius roughly as expected for flat rotation curve halos. The shear values were weighted in proportion to the square root of the luminosity of the lens galaxy. Our results give a value for the average mean rotation velocity of an L_* galaxy halo at r~50-200 kpc of v_* = 238^{+27}_{-30} km per sec for a flat lambda (Omega_m0 = 0.3, Omega_l0 = 0.7) cosmology (v_* = 269^{+34}_{-39} km per sec for Einstein-de Sitter), and with little evidence for evolution with redshift. We find a mass-to-light ratio of \~121\pm28h(r/100 kpc) and these halos constitute Omega ~0.04 pm 0.01 (r/100 kpc) of closure density., Comment: 4 pages, to appear in Proceedings of the Workshop "The Shapes of Galaxies and their Halos", Yale, May 2001

Membership identification is the first step to determine the properties of a star cluster. Low-mass members in particular could be used to trace the dynamical history, such as mass segregation, stellar evaporation, or tidal stripping, of a star cluster in its Galactic environment. We identified member candidates with stellar masses $\sim$0.11--2.4 Msun of the intermediate-age Praesepe cluster (M44), by using Pan-STARRS and 2MASS photometry, and PPMXL proper motions. Within a sky area of 3 deg radius, 1040 candidates are identified, of which 96 are new inclusions. Using the same set of selection criteria on field stars led to an estimate of a false positive rate 16%, suggesting 872 of the candidates being true members. This most complete and reliable membership list allows us to favor the BT-Settl model in comparison with other stellar models. The cluster shows a distinct binary track above the main sequence, with a binary frequency of 20--40%, and a high occurrence rate of similar mass pairs. The mass function is consistent with that of the disk population but shows a deficit of members below 0.3 solar masses. A clear mass segregation is evidenced, with the lowest-mass members in our sample being evaporated from this disintegrating cluster., Comment: ApJ accepted

CFH12K is a 12,228 by 8,192 pixel wide-field imaging camera in operation at the 3.6m Canada-France-Hawaii Telescope (CFHT) since January 1999. It still remains the largest close-packed array in use in astronomy today. The mosaic consists of twelve MIT Lincoln laboratories 2K by 4K thinned backside illuminated CCID-20 devices. The camera is used in broad-band and narrow-band filter direct imaging mode which constrains the devices' operating parameters to ensure the best data quality. Adaptation to the 20-year old CFHT prime focus environment included modifications to reduce the scattered light seen by the camera. Computer facilities have been upgraded and new software has been developed to handle the large amount of data generated. The two terabytes of scientific data taken by the camera in 1999 has proven the success of CFHT's new capability for 42 by 28 square arcminute imaging with high resolution subarcsecond seeing.

The CFH12K is a 12K by 8K CCD mosaic camera for the Canada- France-Hawaii Telescope (CFHT), a 3.6 m telescope located on Mauna Kea, Hawaii. The CFH12K is comprised of twelve 4K by 2K thinned backside-illuminated CCDs, arrange din a close- packed array of two rows each containing six CCDs. Located at the CFHT Prime Focus, the CFH12K provides a 42 by 28 arcminute field-of-view, 0.206 arcsecond per pixel sampling, with a resulting data file of more than 200Mbytes per image. The camera has been designed to exploit the exceptional wide-field imaging capability provided by the CFHT. At the time of its commissioning in January 1999, the CFH12K is the largest thinned close-packed CCD mosaic in astronomy. This paper describes the system architecture, and some of the relevant issues associated with the construction, evaluation, and operation of very large mosaic cameras. Emphasis is given to system design issues, illustrating the CFHT12K as part of a larger system: the CFHT.

In June 1997, NASA made the decision to extend the end of the Hubble Space Telescope (HST) mission from 2005 until 2010. As a result, the age of the instruments on board the HST became a consideration. After careful study, NASA decided to ensure the imaging capabilities of the HST by replacing the Wide Field Planetary Camera 2 with a low-cost facility instrument, the Wide Field Camera 3. This paper provides an overview of the scientific goals and capabilities of the instrument.

The CFH12K is a 12K×8K CCD mosaic camera for the Canada-France-Hawaii Telescope (CFHT), a 3.6m telescope located on Mauna Kea, Hawaii. Positioned at the CFHT Prime Focus (f/4.2), the CFH12K provides a 42 by 28 arcminute field-of-view, 0.206 arcsecond per pixel sampling, with a resulting data file of more than 200 Mbytes per image. At the time of commissioning in January 1999, the CFH12K is the largest thinned close-packed CCD mosaic in astronomy. This paper describes the system architecture and some of the relevant issues associated with the construction, evaluation, and operation of very large mosaic cameras. Emphasis is given to system design issues, illustrating the CFH12K as part of a larger system: the CFHT.

We review the state-of-the-art in large area mosaic CCD camera designs and discuss the technical challenges and future evolution of these instruments. Many of these mosaic cameras are being used as wide-field optical imagers, and toward this end we present a new approach for achieving enhanced resolution (FWHM ≈ O”.12) deep images over large fields of view (l°×l°) using an array of modest telescopes (D ∼ 1.5-1.8m) equipped with mosaics of independently-addressable orthogoral transfer CCD (OTCCD) arrays.

CFH12K is a 12Kx8K wide field imaging camera for the CFHT prime focus. The mosaic consists of twelve MIT Lincoln Laboratory 2Kx4k thinned backside illuminated CCID-20 devices. The devices’ operating parameters have been optimised to ensure the best data quality for use in broad and narrow band filter imaging mode. Adaptation to the CFHT prime focus environment included modifications to reduce the scattered light seen by the CFH12K. Science data taken by the camera has proven the success of CFHT’s new capability for 42×28 square arcminute imaging with high-resolution subarcsecond seeing.

We present measurements of the extended dark halo profiles of bright early type galaxies at redshifts 0.1 to 0.9 obtained via galaxy-galaxy lensing analysis of images taken at the CFHT using the UH8K CCD mosaic camera. Six half degree fields were observed for a total of 2 hours each in I and V, resulting in catalogs containing ~20 000 galaxies per field. We used V-I color and I magnitude to select bright early type galaxies as the lens galaxies, yielding a sample of massive lenses with fairly well determined redshifts and absolute magnitudes M ~ M_* \pm 1. We paired these with faint galaxies lying at angular distances 20" to 60", corresponding to physical radii of 26 to 77 kpc (z = 0.1) and 105 to 315 kpc (z = 0.9), and computed the mean tangential shear of the faint galaxies. The shear falls off with radius roughly as expected for flat rotation curve halos. The shear values were weighted in proportion to the square root of the luminosity of the lens galaxy. Our results give a value for the average mean rotation velocity of an L_* galaxy halo at r~50-200 kpc of v_* = 238^{+27}_{-30} km per sec for a flat lambda (Omega_m0 = 0.3, Omega_l0 = 0.7) cosmology (v_* = 269^{+34}_{-39} km per sec for Einstein-de Sitter), and with little evidence for evolution with redshift. We compare to halo masses measured by other groups/techniques. We find a mass-to-light ratio of ~121\pm28h(r/100 kpc) and these halos constitute Omega ~0.04 \pm 0.01(r/100 kpc) of closure density. (abridged), Comment: Accepted for publication in ApJ (minor modifications) - 32 pages, 11 figs, 5 tables

We propose a new strategy for obtaining enhanced resolution (FWHM = 0.12 arcsec) deep optical images over a wide field of view. As is well known, this type of image quality can be obtained in principle simply by fast guiding on a small (D = 1.5m) telescope at a good site, but only for target objects which lie within a limited angular distance of a suitably bright guide star. For high altitude turbulence this 'isokinetic angle' is approximately 1 arcminute. With a 1 degree field say one would need to track and correct the motions of thousands of isokinetic patches, yet there are typically too few sufficiently bright guide stars to provide the necessary guiding information. Our proposed solution to these problems has two novel features. The first is to use orthogonal transfer charge-coupled device (OTCCD) technology to effectively implement a wide field 'rubber focal plane' detector composed of an array of cells which can be guided independently. The second is to combine measured motions of a set of guide stars made with an array of telescopes to provide the extra information needed to fully determine the deflection field. We discuss the performance, feasibility and design constraints on a system which would provide the collecting area equivalent to a single 9m telescope, a 1 degree square field and 0.12 arcsec FWHM image quality., 46 pages, 22 figures, submitted to PASP, a version with higher resolution images and other supplementary material can be found at http://www.ifa.hawaii.edu/~kaiser/wfhri

We are developing a high-resolution cross-dispersed echelle spectrograph for installation at one of the coude foci of the new AEOS 3.67 meter telescope, operated by the Air Force Space Command on Haleakala, Maui, Hawaii. The spectrograph will consist of two major subsystems, an optical arm for the wavelength range 0.5-1.0 microns and a SWIR arm for the range 1.0-2.5 microns. The optical arm will include a mosaic 4096 by 4096 thinned CCD array, providing coverage of the wavelength range in two settings at a resolving power of 50,000. The CCD camera will be operated in frame-transfer mode. The IR arm will consist of a compact, folded cross- dispersed cryogenic echelle spectrography. The SWIR detector will be a 2048 by 2048 HgCdTe array, based on the existing HAWAII 1024 by 1024 devices. The large-format detector will permit coverage of the entire J or H band in a single grating setting with a resolving power of 60,000, and the K band in two settings. The high resolution, coupled with careful attention to scattering and stray light in the optical system, will permit exploitation of the low sky background between the strong OH airflow lines. Adequate order separation will be maintained to permit work on moderately extended objects while still retaining sky subtraction capability. The spectrography is expected to be available for use in early 2000.

We have entered an era of large CCD mosaic camera construction with many observatories developing large mosaic focal planes for wide field cameras and spectrographs. In this review, we outline the history of CCD mosaic development, describe the current state of the art while illustrating the many projects underway, and attempt to peer into the future.

The Institute for Astronomy at the University of Hawaii has an active program in detector development, both in optical CCDs and Infrared Arrays. Below, I briefly describe the optical detector program and the existing scientific CCD cameras in place on UH facilities on Mauna Kea. I also list present and future development efforts.

We present the results of a CCD imaging survey for gravitational lensing in a sample of 38 X-ray-selected clusters of galaxies. Our sample consists of the most X-ray luminous (Lx>= 2x10^{44} erg s^{-1}) clusters selected from the Einstein Observatory Extended Medium Sensitivity Survey (EMSS) that are observable from Mauna Kea (dec > -40deg). The sample spans a redshift range of 0.15 < z < 0.823 and includes 5 clusters with z > 0.5. CCD images of the clusters were obtained in excellent seeing. There is evidence of strong gravitational lensing in the form of giant arcs (length l > 8'', axis ratio l/w > 10) in 8 of the 38 clusters. Two additional clusters contain shorter arclets, and 6 more clusters contain candidate arcs that require follow-up observations to confirm their lensing origin. Since the survey does not have a uniform surface brightness limit we do not draw any conclusion based on the statistics of the arcs found. We note, however, that 60% (3 of 5) of the clusters with Lx > 10^{45} erg s^{-1}, and none of the 15 clusters with Lx < 4x10^{44} erg s^{-1} contain giant arcs, thereby confirming that high X-ray luminosity does identify the most massive systems, and thus X-ray selection is the preferred method for finding true, rich clusters at intermediate and high redshifts. The observed geometry of the arcs, most of which are thin, have large axis ratios (l/w > 10), and are aligned orthogonal to the optical major axes of the clusters, indicate the cluster core mass density profiles must be compact (steeper than isothermal). In several cases, however, there is also some evidence, in the form of possible radial arcs, for density profiles with finite core radii., Latex file, 17 pages, 7 jpeg figures, to be published in Astronomy and Astrophysics Supplements

We describe recent work in the area of large, back-illuminated CCD imagers at M.I.T. Lincoln Laboratory as well as new technology applicable to astronomy. We completed in 1995 the development of a 2560 x 1960-pixel frame-transfer imager that filled a 100-mm wafer and several back-illuminated versions of this device were completed. More recently we have begun the development, in collaboration with the U. of Hawaii, of a three-side abuttable 2k x 4k CCD for a multi-chip focal plane. In the unused chord area of the wafer layout, we added test imagers as development vehicles for blooming control and for the demonstration of a CCD that is capable of charge transfer in all four directions. We expect the latter to find application as an electronic means of performing tip-tilt correction to compensate for atmospheric turbulence.

We present IR surface brightness fluctuation (SBF) distance measurements to NGC 4889 in the Coma cluster and to NGC 3309 and NGC 3311 in the Hydra cluster. We explicitly corrected for the contributions to the fluctuations from globular clusters, background galaxies, and residual background variance. We measured a distance of 85 +/- 10 Mpc to NGC 4889 and a distance of 46 +/- 5 Mpc to the Hydra cluster. Adopting recession velocities of 7186 +/- 428 km/s for Coma and 4054 +/- 296 km/s for Hydra gives a mean Hubble constant of H_0 = 87 +/- 11 km/s/Mpc. Corrections for residual variances were a significant fraction of the SBF signal measured, and, if underestimated, would bias our measurement towards smaller distances and larger values of H_0. Both NICMOS on the Hubble Space Telescope and large-aperture ground-based telescopes with new IR detectors will make accurate SBF distance measurements possible to 100 Mpc and beyond., Comment: 24 pages, 4 PostScript figures, 2 JPEG images; accepted for publication in ApJ

We describe the design and data sample from the DEEP2 Galaxy Redshift Survey, the densest and largest precision-redshift survey of galaxies at z ~ 1 completed to date. The survey has conducted a comprehensive census of massive galaxies, their properties, environments, and large-scale structure down to absolute magnitude M_B = -20 at z ~ 1 via ~90 nights of observation on the DEIMOS spectrograph at Keck Observatory. DEEP2 covers an area of 2.8 deg^2 divided into four separate fields, observed to a limiting apparent magnitude of R_AB=24.1. Objects with z < 0.7 are rejected based on BRI photometry in three of the four DEEP2 fields, allowing galaxies with z > 0.7 to be targeted ~2.5 times more efficiently than in a purely magnitude-limited sample. Approximately sixty percent of eligible targets are chosen for spectroscopy, yielding nearly 53,000 spectra and more than 38,000 reliable redshift measurements. Most of the targets which fail to yield secure redshifts are blue objects that lie beyond z ~ 1.45. The DEIMOS 1200-line/mm grating used for the survey delivers high spectral resolution (R~6000), accurate and secure redshifts, and unique internal kinematic information. Extensive ancillary data are available in the DEEP2 fields, particularly in the Extended Groth Strip, which has evolved into one of the richest multiwavelength regions on the sky. DEEP2 surpasses other deep precision-redshift surveys at z ~ 1 in terms of galaxy numbers, redshift accuracy, sample number density, and amount of spectral information. We also provide an overview of the scientific highlights of the DEEP2 survey thus far. This paper is intended as a handbook for users of the DEEP2 Data Release 4, which includes all DEEP2 spectra and redshifts, as well as for the publicly-available DEEP2 DEIMOS data reduction pipelines. [Abridged], submitted to ApJS; data products available for download at http://deep.berkeley.edu/DR4/