Wesley N. Colley

Wesley N. Colley
University of Alabama in Huntsville | UAH · Information Technology and Systems Center

Doctor of Philosophy

About

40
Publications
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872
Citations

Publications

Publications (40)
Article
A joint analysis of data collected by the Planck and BICEP2+Keck teams has previously given $r = 0.09^{+0.06}_{-0.04}$ for BICEP2 and $r = 0.02^{+0.04}_{-0.02}$ for Keck. Analyzing BICEP2 using its published noise estimate, we had earlier (Colley & Gott 2015) found $r = 0.09 \pm 0.04$, agreeing with the final joint results for BICEP2. With the Keck...
Article
We have analysed the genus topology of the BICEP2 B-modes and found them to be Gaussian random phase as expected if they have a cosmological origin. These BICEP2 B-modes can be produced by gravity waves in the early Universe, but question has arisen as to whether these B-modes (for 50 < l < 120) may instead be produced by foreground-polarized dust...
Conference Paper
Full-text available
Making use of the concepts of the activity diagrams of the Unified Modeling Language, this paper defines an important class of workflows, called flow independent workflows, which are deterministic in the sense that if a flow independent workflow is given the same multi-set of resources as input over and over again, it will produce the same output e...
Article
In this paper we outline statistical methods used to analyze the behavior signatures that are hidden deep within data on terrorist attacks. These methods have the potential to allow military commanders to identify trends in attacks and to make informed decisions about how best to prevent future attacks. While this work focuses primarily on terroris...
Chapter
System Class Modeling and Simulation (M&S) Strategy Modeling Approach Model Examples Simulating Continuous Systems Simulation Implementation Conclusion References
Article
Full-text available
CCD photometry of the gravitational lens system 0957+561A, B in the g and r bands was obtained on alternate nights, weather permitting, from 1994 December through 1995 May using the Double Imaging Spectrograph (DIS) on the Apache Point Observatory (APO) 3.5 m telescope. The remote observing and fast instrument change capabilities of this facility a...
Article
Full-text available
Continued photometric monitoring of the gravitational lens system 0957+561A, B in the g and r bands with the Apache Point Observatory (APO) 3.5 m telescope during 1996 shows a sharp g-band event in the trailing (B) image light curve at the precise time predicted in an earlier paper. The prediction was based on the observation of the event during 19...
Article
We have simulated cosmic microwave background (CMB) anisotropy maps for several COBE-Differential Microwave Radiometer experiment normalized cold dark matter (CDM) cosmogonies, to make predictions for the MAP experiment, an upcoming whole-sky CMB anisotropy space mission. We have studied the sensitivity of the simulated MAP data to cosmology, sky c...
Article
We address the following question: How does one reliably distinguish rapid microlensing events from atmospheric or instrumental effects on observed brightness fluctuations of distant objects? Our approach was to do a controlled, albeit limited, experiment, the first of its kind: observe Q0957+561A,B simultaneously through filters of the same charac...
Article
Full-text available
An observing campaign with 10 participating observatories has undertaken to monitor the optical brightness of the Q0957 gravitationally lensed quasar for 10 consecutive nights in 2000 January. The resulting A image brightness curve has significant brightness fluctuations and makes a photometric prediction for the B image light curve for a second ca...
Article
In 2004, we used a very simple, but surprisingly effective method to successfully predict the outcome of the U.S. Presidential election. Using the median poll in the last month for each state, we correctly predicted the results in all states but one (Hawaii). Just as we had originally hoped, the method made it possible to predict successfully the r...
Article
We have independently measured the genus topology of the temperature fluctuations in the cosmic microwave background seen in the Wilkinson Microwave Anisotropy Probe (WMAP) 3-year data. A genus analysis of the WMAP data indicates consistency with Gaussian random-phase initial conditions, as predicted by standard inflation. We set 95% confidence lim...
Article
It is useful to have mathematical criteria for evaluating errors in map projections. The Chebyshev criterion for minimizing rms (root mean square) local scale factor errors for conformal maps has been useful in developing conformal map projections of continents. Any local error criterion will be minimized ultimately by map projections with multiple...
Article
We have independently measured the genus topology of the temperature fluctuations in the cosmic microwave background seen by the Wilkinson Microwave Anisotropy Probe (WMAP). A genus analysis of the WMAP data indicates consistency with Gaussian random-phase initial conditions, as predicted by standard inflation.
Article
We reanalyze brightness data sampled intensively over five nights at two epochs separated by the quasar lens time delay to examine the nature of the observed microlensing. We find strong evidence for a microlensing event with an amplitude of 1% and a timescale of 12 hr. The existence of such rapid microlensing, albeit at low amplitude, imposes cons...
Article
Full-text available
We report on an observing campaign in March 2001 to monitor the brightness of the later arriving Q0957+561 B image in order to compare with the previously published brightness observations of the (first arriving) A image. The 12 participating observatories provided 3543 image frames which we have analyzed for brightness fluctuations. From our class...
Article
Full-text available
We present a data set of images of the gravitationally lensed quasar Q2237+0305, that was obtained at the Apache Point Observatory (APO) between June 1995 and January 1998. Although the images were taken under variable, often poor seeing conditions and with coarse pixel sampling, photometry is possible for the two brighter quasar images A and B wit...
Article
The field of the z=0.4 galaxy cluster ZwCl0024+1654 includes a more distant z=1.7 galaxy that has been gravitationally lensed into several magnified and amplified images. Reconstruction of the lensed galaxy reveals a striking ring morphology in the restframe ultraviolet, prompting the ``Pretzel Galaxy'' nickname. To determine whether this primeval...
Article
Full-text available
We have re-reduced 1600 CCD images of the Twin Quasar Q0957+561, taken over 25 nights with 4 minute time resolution. The new reduction uses HST imaging to subtract the lens galaxy accurately. This refined photometry shows variations of order a percent during the typical night. Two runs, separated by the now widely accepted 417 day time delay allow...
Article
If the halo of the lensing galaxy 0957+561 is made of massive compact objects (MACHOs), they must affect the lightcurves of the quasar images Q0957+561 A and B differently. We search for this microlensing effect in the double quasar by comparing monitoring data for the two images A and B - obtained with the 3.5m Apache Point Observatory from 1995 t...
Article
Full-text available
Since 1997, a program of observations of gravitational lens systems (GLS) with the 1.5-m telescope of the high-altitude Maidanak Observatory has been carried out by joint efforts of seven institutions from five countries. The Q2237+0305, Q0957+561, SBS 1520+530, and other GLS were observed in VRI spectral bands using the TI 800×800, Pictor 416 and...
Article
Full-text available
We have continued our effort to re-reduce archival Q0957+561 brightness monitoring data and present results for 1629 R-band images using the methods for galaxy subtraction and seeing correction reported previously. The new dataset comes from 4 observing runs, several nights apiece, with sampling of typically 5 minutes, which allows the first measur...
Article
We measure the topology (genus curve) of the galaxy distribution in a mock redshift catalog designed to resemble the upcoming Sloan Digital Sky Survey (SDSS). The catalog, drawn from a large N-body simulation of a Lambda-CDM cos- mological model, mimics the anticipated spectroscopic selection procedures of the SDSS in some detail. Sky maps, redshif...
Article
Full-text available
Since the persuasive determination of the time-delay in Q0957+561, much interest has centered around shifting and subtracting the A and B light-curves to look for residuals due to microlensing. Solar mass objects in the lens galaxy produce variations on timescales of decades, with amplitudes of a few tenths of a magnitude, but MACHO's (with masses...
Article
We have previously found in the Hubble Deep Field a significant angular correlation of faint, high color-redshift objects on scales below one arcsecond, or several kiloparsecs in metric size. A correlation at this scale is most likely due to physical associations. We examine the correlation and nearest neighbor statistics to conclude that 38% of th...
Article
We consider the feasibility of directly observing gravitational microlensing in extra-galactic sources, whose stars are not generally resolved. This precludes use of the simple optical depth to microlensing formulation, which is applicable only to resolved stars. We, instead, extend this method to consider observational constraints, such as seeing,...
Article
We describe high resolution V and I band images obtained with the HST Planetary Camera of the center of the prototype starburst galaxy M82. The deconvolved images reveal a remarkable complex of over 100 compact, luminous "super" star clusters, concentrated to the inner few 100 pcs of the galaxy. These clusters typically have half-peak intensity siz...
Article
We have simulated cosmic microwave background (CMB) anisotropy maps for several COBE-DMR-normalized cold dark matter (CDM) cosmogonies, to make predictions for the upcoming MAP experiment. We have studied the sensitivity of the simulated MAP data to cosmology, sky coverage, and instrumental noise. With accurate knowledge of instrumental noise, MAP...
Article
We have previously found in the Hubble Deep Field a significant angular correlation of faint, high color-redshift objects on scales below one arcsecond, or several kiloparsecs in metric size. A correlation at this scale is most likely due to physical associations. We examine the correlation and nearest neighbor statistics to conclude that 38% of th...
Article
We have measured the topology (genus) of the density distribution of large-scale structure observed in the Las Campanas Redshift Survey (LCRS). The LCRS is complete to magnitude 17.5, and contains nearly 24000 galaxies with median redshift of 30000 km/s. The large volume and large number of galaxies allows sampling of nearly 100 independent structu...
Article
I shall discuss recent work on the Hubble Deep Field. We have measured the two-point angular correlation function of sources detected in the field. We find a correlation peaked between 0.25 and 0.4 arcseconds with an amplitude of 2 or greater. This angular size corresponds to physical scales of a few kiloparsecs, nearly independent of redshift (bey...
Article
Continued photometric monitoring of the gravitational lens system 0957+561A,B in the g and r bands with the Apache Point Observatory (APO) 3.5 m telescope during 1996 shows a sharp g band event in the trailing (B) image light curve at the precise time predicted in an earlier paper. The prediction was 1 Supported by the Fannie and John Hertz Foundat...
Article
The Hubble Deep Field 2 (HDF) offers the best view to date of the optical sky at faint magnitudes and small angular scales. Early reports suggested that faint source counts continue to rise to the completeness limit of the data. In this letter, we investigate the possibility that some of these sources are in fact giant HII regions or merger fragmen...
Article
The Hubble Deep Field (HDF) offers the best view to date of the optical sky at faint magnitudes and small angular scales. Early reports suggested that faint source counts continue to rise to the completeness limit of the data, which implies a very large number of galaxies. In this Letter, we use the two-point angular correlation function and number...
Article
We have measured the topology (genus) of the fluctuations in the cosmic microwave background seen in the recently completed (four-year) data set produced by the COBE satellite. We find that the genus is consistent with that expected from a random-phase Gaussian distribution, as might be produced naturally in inflationary models.
Article
We have used a set of equations developed by Pringle to follow the evolution of a viscous twisted disk in a galaxy-like potential that is stationary or tumbling relative to inertial space. In an axisymmetric potential, the disk settles to the equatorial plane at a rate largely determined by the coefficient v2, associated with shear perpendicular to...
Article
A unique reconstruction of the image of a high redshift source galaxy responsible for multiple long arcs in the z = 0.4 cluster 0024+1654 is obtained by inverse lensing. Deep B and I imaging with the Hubble Space Telescope 5 enables high resolution of the arcs due to strong gravitational lensing of the background source. The gravitational lens in t...
Article
We describe high resolution V and I band images obtained with the HST Planetary Camera of the center of the prototype starburst galaxy M82. The deconvolved images reveal a remarkable complex of over 100 compact, luminous "super" star clusters, concentrated to the inner few 100 pcs of the galaxy. These clusters typically have half-peak intensity siz...
Article
We study the naked-eye observability of microlensing events for both known stars and possible massive compact halo objects (MACHOs). We find that if both the dark matter disc and halo are composed of MACHOs in the Jupiter-mass range, microlensing events of naked-eye stars, undergoing at least one magnitude of magnification occur at the rate of 1 pe...
Article
We consider the feasibility of directly observing gravitational microlensing in extragalactic sources, whose stars are not generally resolved. This precludes use of the simple optical depth to microlensing formulation, which is applicable only to resolved stars. We, instead, extend this method to consider observational constraints, such as seeing,...