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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

The Telescopio San Pedro Mártir project

Richer, Michael G., Lee, William H., González, Jesús, Jannuzi, Buell T., Sánchez, Beatriz, Rosales Ortega, Fabián, Alcock, Charles, Carramiñana Alonso, Alberto, García Díaz, Ma. Teresa, Gutiérrez, Leonel, Herrera, Joel, Hill, Derek, Norton, Timothy J., Pedrayes, Maria H., Pérez-Calpena, Ana, Reyes-Ruíz, Mauricio, Serrano Guerrero, Hazael, Sierra, Gerardo, Teran, Jose, Urdaibay, David, Uribe, Jorge A., Watson, Alan M., Zaritsky, Dennis, García Vargas, Marisa 27 July 2016 (has links)
The Telescopio San Pedro Martir project intends to construct a 6.5m telescope to be installed at the Observatorio Astronomico Nacional in the Sierra San Pedro Martir in northern Baja California, Mexico. The project is an association of Mexican institutions, lead by the Instituto Nacional de Astrofisica, Optica y Electronica and the Instituto de Astronomia at the Universidad Nacional Autonoma de Mexico, in partnership with the Smithsonian Astrophysical Observatory and the University of Arizona's Department of Astronomy and Steward Observatory. The project is currently in the planning and design stage. Once completed, the partners plan to operate the MMT and TSPM as a binational astrophysical observatory.
42

Automation and control of the MMT thermal system

Gibson, J. D., Porter, Dallan, Goble, William 26 July 2016 (has links)
This study investigates the software automation and control framework for the MMT thermal system. Thermal-related effects on observing and telescope behavior have been considered during the entire software development process. Regression analysis of telescope and observatory subsystem data is used to characterize and model these thermal-related effects. The regression models help predict expected changes in focus and overall astronomical seeing that result from temperature variations within the telescope structure, within the primary mirror glass, and between the primary mirror glass and adjacent air (i.e., mirror seeing). This discussion is followed by a description of ongoing upgrades to the heating, ventilation and air conditioning (HVAC) system and the associated software controls. The improvements of the MMT thermal system have two objectives: 1) to provide air conditioning capabilities for the MMT facilities, and 2) to modernize and enhance the primary mirror (M1) ventilation system. The HVAC upgrade necessitates changes to the automation and control of the M1 ventilation system. The revised control system must factor in the additional requirements of the HVAC system, while still optimizing performance of the M1 ventilation system and the M1's optical behavior. An industry-standard HVAC communication and networking protocol, BACnet (Building Automation and Control network), has been adopted. Integration of the BACnet protocol into the existing software framework at the MMT is discussed. Performance of the existing automated system is evaluated and a preliminary upgraded automated control system is presented. Finally, user interfaces to the new HVAC system are discussed.
43

SOUL: the Single conjugated adaptive Optics Upgrade for LBT

Pinna, E., Esposito, S., Hinz, P., Agapito, G., Bonaglia, M., Puglisi, A., Xompero, M., Riccardi, A., Briguglio, R., Arcidiacono, C., Carbonaro, L., Fini, L., Montoya, M., Durney, O. 27 July 2016 (has links)
We present here SOUL: the Single conjugated adaptive Optics Upgrade for LBT. Soul will upgrade the wavefront sensors replacing the existing CCD detector with an EMCCD camera and the rest of the system in order to enable the closed loop operations at a faster cycle rate and with higher number of slopes. Thanks to reduced noise, higher number of pixel and framerate, we expect a gain (for a given SR) around 1.5-2 magnitudes at all wavelengths in the range 7.5 <mR <18. The correction at short wavelength will be greatly improved (SR>70% in I-band and 0.6asec seeing) and the sky coverage will be multiplied by a factor 5 at all galactic latitudes. Upgrading the SCAO systems at all the 4 focal stations, SOUL will provide these benefits in 2017 to the LBTI interferometer and in 2018 to the 2 LUCI NIR spectro-imagers. In the same year the SOUL correction will be exploited also by the new generation of LBT instruments: V-SHARK, SHARK-NIR and iLocater.
44

Cloudy with a chance of water : investigating hot Jupiter exoplanet atmospheres through observation and analysis

Wakeford, Hannah Ruth January 2015 (has links)
Since the discovery of the first exoplanet orbiting a sun-like star in 1995, the fundamental questions as to the formation of our Solar System have met a paradigm shift. The presence of hot Jupiter exoplanets, Jupiter sized worlds rapidly orbiting their host stars, was unlike anything previously seen or predicted. The later discovery of these strange new worlds transiting their stars opened up a new realm of studies into their atmospheres using transit spectroscopy to separate the signals between the star and planetary atmosphere. This thesis investigates the transmission spectral properties of hot Jupiter exoplanets through observations and theoretical analysis from the search for H2O in the near-IR to the signatures of cloud condensates in the IR. Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) observations of transiting hot Jupiters were used to investigate the atmospheric composition over water bands in the near infrared. We put forward a new analysis method to treat the varying systematics seen across transit datasets in a consistent and robust way, in which we marginalise over a grid of possible systematic models used to correct the lightcurves, with each model contributing to the extracted spectrum based on its statistical likelihood. We apply this new method to five previously studied hot Jupiter exoplanet transmission spectra and make direct comparisons between the planetary atmospheres. An apparent dichotomy emerges between two possible sub-classes of hot Jupiter atmospheres with clouds and hazes playing a key role. WFC3 appears to cover a critical wavelength range in exoplanet atmospheres where clouds and hazes potentially obscure the expected molecular signatures in systems where they are found to be obscured in the optical. Using analytical models following Mie theory, we explore the potential atmospheric transmission spectral signatures that would be caused by a variety of cloud condensates in hot Jupiter atmospheres. We find that the observed optical slope representing Rayleigh scattering at high altitudes can constrain the cloud condensate particle size and can be used as a diagnostic for potential condensate features in the IR where almost all condensate absorption features occur. We find that the major transmission spectral absorption features are generated by the vibrational modes of the major diatomic bond pair in each condensate species, which is often seen in the IR at 5-25 microns, and explore the potential for future JWST investigations using MIRI.
45

Using a two-scintillator paddle telescope for cosmic ray flux measurements

Camp, David L 20 December 2012 (has links)
A two-scintillator paddle muon telescope with variable angular acceptance at the earth's surface was used to study correlations between flux distribution and barometric pressure. The detector was placed in 2 different locations around Georgia State University with varying paddle separations of 0, 7, and 14 inches. Correlation and anti-correlation analyses were conducted by using the muon count from the detector along with the barometric pressure, surface temperature, stratospheric temperature and solar activity. It was observed that there was a short and long-term variation relationship between cosmic ray counts and barometric pressure and also cosmic ray counts and temperature. No significant relationship was found between cosmic ray flux and solar activity. A new two-scintillator paddle telescope with larger detecting area was constructed in order to observe a stronger correlation between cosmic ray flux and pressure.
46

A Practical Alignment Algorithm For Cassegrain Type Telescopes

Benli Ozturk, Esra 01 August 2012 (has links) (PDF)
Focal plane corrected Cassegrain type optical systems have been widely used in various fields. The axial alignment of complex optical systems is not easy and a practical alignment method is needed for such systems. Tilts, decenters and axial motion of elements or group of elements in the system are the typical alignment parameters. Interferometric measurement is an effective way to see the errors caused by the misalignment of each element in an optical system. In this thesis, alignment of a Cassegrain type telescope will be examined by using interferometric measurements and modulation transfer function simulations.
47

Scales of Seeing

Douglass, A.E. 08 April 1898 (has links)
No description available.
48

The Effects of Mountains On the Quality of the Atmosphere

Douglass, A.E. January 1899 (has links)
No description available.
49

Kaluza Klein Dark Matter Analysis with the AMANDA Neutrino Telescope

Han, Kahae January 2010 (has links)
In this work the search for the dark matter arising from a model of extra dimensions, otherwise known as Kaluza Klein WIMPs, on the data taken with the AMANDA neutrino telescope in the South Pole is presented. The limit on the dark matter from the Kaluza Klein Solar WIMPs analysis on the data taken from year 2001 to 2003 is derived.
50

Optimizing the Optical Calibration Performance of a Multi-Object Adaptive Optics Instrument

Pham, Laurie Nhu An 17 December 2013 (has links)
Multi-Object Adaptive Optics (MOAO) is an adaptive optics technique being developed for Extremely Large Telescopes that will allow simultaneous observation of approximately 20 targets in a several arc-minute field of regard. Raven is an MOAO pathfinder developed by the Adaptive Optics Laboratory of the University of Victoria, in collaboration with the National Research Council of Canada and the Subaru Telescope. It will be the first MOAO instrument on a 8-m class telescope, will demonstrate that MOAO technical challenges such as open-loop control and calibration are achievable on-sky and will deliver science results using three natural guide stars and two science arms on ∼ 3.5′ field-of-regard. The open-loop approach makes the need for calibration even more crucial. An important part of the calibration process resides in the misregistration of the wavefront sensors (WFSs) with the deformable mirrors (DMs) because the sensing elements are located before the correcting ones. This problem is solved using a cal- ibration DM seen by all WFSs in the system that permits the open-loop WFS to be registered to the science DMs. The method developed in this thesis registers the position of the DM actuators to the WFSs and gives misregistration values. These results are then used to better align the instrument, to have a better knowledge of the positions of the different optical components and generate new ways to perform the AO correction. Using the registration parameters results, synthetic interaction matrices are created in order to improve the AO correction. Calibration tests are also presented in this thesis. They show complementary tests to the expected requirements to expand the knowledge of the calibration unit behaviour. / Graduate / 0548 / 0752 / lpham@uvic.ca

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