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Jacoby G.H.,WIYN Observatory | Kronberger M.,Deepskyhunters Collaboration | Patchick D.,Deepskyhunters Collaboration | Teutsch P.,Deepskyhunters Collaboration | And 8 more authors.
Publications of the Astronomical Society of Australia | Year: 2010

Recent Hα surveys such as SHS and IPHAS have improved the completeness of the Galactic planetary nebula (PN) census. We now know of ∼3000 PNe in the Galaxy, but this is far short of most estimates, typically ∼25 000 or more for the total population. The size of the Galactic PN population is required to derive an accurate estimate of the chemical enrichment rates of nitrogen, carbon, and helium. In addition, a high PN count (>20 000) is strong evidence that most main-sequence stars of mass 1-8 M⊙ will go through a PN phase, while a low count (<10 000) argues that special conditions (e.g. close binary interactions) are required to form a PN. We describe a technique for finding hundreds more PNe using the existing data collections of the digital sky surveys, thereby improving the census of Galactic PNe. © Astronomical Society of Australia 2010. Source


Meixner M.,US Space Telescope Science Institute | Meixner M.,U.S. National Optical Astronomy Observatories | Smee S.,Johns Hopkins University | Doering R.L.,US Space Telescope Science Institute | And 13 more authors.
Publications of the Astronomical Society of the Pacific | Year: 2010

We present the design overview and on-telescope performance of the WIYN High Resolution Infrared Camera (WHIRC). As a dedicated near-infrared (0.8-2.5 μm) camera on the WIYN Tip-Tilt Module (WTTM) port, WHIRC can provide near-diffraction-limited imaging with an FWHM of ∼0.25″ at K s with active WTTM correction and does deliver typical imaging with an FWHM of ∼0.6″ without WTTM. WHIRC uses a 2048 × 2048 HgCdTe array from Raytheon's VIRGO line, which has been developed for the VISTA project. The WHIRC filter complement includes J, H, Ks, and 10 narrowband filters. WHIRC's compact design makes it the smallest near-infrared camera with this capability. We determine a gain of 3.3 ± 0.2 e -ADU-1 via a photon transfer analysis and a readout noise of ∼19 e- . A measured dark current of 0.13 e- s -1 indicates that the cryostat is extremely light tight. A. plate scale of 0.099″ × 0.10″ pixel-1 results in a field of view (FOV) of 3.3′ × 3.4′, which is a compromise between the highest angular resolution achievable and the largest FOV correctable by WTTM. Measured throughput values (∼0.27 ± 0.02 in H band) are consistent with those predicted for WHIRC based on an analysis of individual optical elements and detector quantum efficiency (QE). WHIRC's photometric quality is better than ∼0.02 magnitudes in all bands. WHIRC is a general use instrument at the WIYN telescope enabling high-definition near-infrared imaging studies of a wide range of astronomical phenomena including star formation regions, stellar populations, and interstellar medium in nearby galaxies, high-z galaxies, and transient phenomena. © 2010. The Astronomical Society of the Pacific. All rights reserved. Source


Young M.D.,Indiana University | Kotulla R.,University of Wisconsin - Milwaukee | Gopu A.,Indiana University | Liu W.,WIYN Observatory
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2014

As imaging systems improve, the size of astronomical data has continued to grow, making the transfer and processing of data a significant burden. To solve this problem for the WIYN Observatory One Degree Imager (ODI), we developed the ODI-Portal, Pipeline, and Archive (ODI-PPA) science gateway, integrating the data archive, data reduction pipelines, and a user portal. In this paper, we discuss the integration of the QuickReduce (QR) pipeline into PPA's Tier 2 processing framework. QR is a set of parallelized, stand-alone Python routines accessible to all users, and operators who can create master calibration products and produce standardized calibrated data, with a short turn-around time. Upon completion, the data are ingested into the archive and portal, and made available to authorized users. Quality metrics and diagnostic plots are generated and presented via the portal for operator approval and user perusal. Additionally, users can tailor the calibration process to their specific science objective(s) by selecting custom datasets, applying preferred master calibrations or generating their own, and selecting pipeline options. Submission of a QuickReduce job initiates data staging, pipeline execution, and ingestion of output data products all while allowing the user to monitor the process status, and to download or further process/analyze the output within the portal. User-generated data products are placed into a private user-space within the portal. ODI-PPA leverages cyberinfrastructure at Indiana University including the Big Red II supercomputer, the Scholarly Data Archive tape system and the Data Capacitor shared file system. © 2014 SPIE. Source


Harbeck D.,WIYN Observatory | Gallagher III J.,University of Wisconsin - Madison | Crnojevic D.,University of Edinburgh
Monthly Notices of the Royal Astronomical Society | Year: 2012

We investigate the star cluster population in the outer parts of the starburst galaxy NGC 5253 using archive images taken with the Hubble Space Telescope's Advanced Camera for Surveys. Based on the F415W, F555W and F814W photometry ages and masses are estimated for bona fide star cluster candidates. We find three potentially massive (≥10 5 M ⊙) star clusters at ages of the order of 1-2 Gyr, implying, if confirmed, a high global star formation rate in NGC 5253 during that epoch. This result underlines earlier findings that the current starburst is just one episode in a very active dwarf galaxy. © 2012 The Authors Monthly Notices of the Royal Astronomical Society © 2012 RAS. Source


Jacoby G.H.,NOAO | Howell S.B.,NOAO | Harbeck D.R.,WIYN Observatory | Sawyer D.G.,NOAO
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2010

QUOTA is an 8Kx8K (16'x16') optical imager using four 4Kx4K orthogonal transfer CCDs arrays (OTAs). Each OTA has 64 nearly independent CCDs having 480x494 12μm pixels. By reading out several of the CCDs rapidly (20 Hz), the centroids of the stars in those CCDs can be used to measure image motion due to atmospheric effects, telescope shake, and guide errors. Motions are fed back to the remaining 250 CCDs that continue to integrate normally, allowing a shift of the collecting charge packets so that they always fall under the moving star images, thereby effecting low order adaptive optics tip/tilt correction in the silicon to improve image quality. As a bonus, the stars that are read rapidly can be studied for high speed photometric variability. QUOTA was conceived to be a prototype for WIYN's 32Kx32K One Degree Imager (ODI), providing a means to test and advance the technical developments for the larger imager (e.g., detectors, controllers, optics, coatings, cooling, and software). QUOTA will have been to the WIYN 3.5-m telescope only twice in its current configuration, but it provided a wealth of information that has been useful to the engineering of ODI. We focus on the areas in which ODI has benefited from QUOTA in this report. © 2010 Copyright SPIE - The International Society for Optical Engineering. Source

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