Topology of the Galaxy Distribution in the Hubble Deep Fields

We have studied topology of the distribution of the high redshift galaxies identified in the Hubble Deep Field (HDF) North and South. The two-dimensional genus is measured from the projected distributions of the HDF galaxies at angular scales from $3.8''$ to $6.1''$. We have also divided the samples into three redshift slices with roughly equal number of galaxies using photometric redshifts to see possible evolutionary effects on the topology. The genus curve of the HDF North clearly indicates clustering of galaxies over the Poisson distribution while the clustering is somewhat weaker in the HDF South. This clustering is mainly due to the nearer galaxies in the samples. We have also found that the genus curve of galaxies in the HDF is consistent with the Gaussian random phase distribution with no significant redshift dependence.Comment: 14 pages, 4 figures, submitted to Ap

Effects of Foreground Contamination on the Cosmic Microwave Background Anisotropy Measured by MAP

We study the effects of diffuse Galactic, far-infrared extragalactic source, and radio point source emission on the cosmic microwave background (CMB) anisotropy data anticipated from the MAP experiment. We focus on the correlation function and genus statistics measured from mock MAP foreground-contaminated CMB anisotropy maps generated in a spatially-flat cosmological constant dominated cosmological model. Analyses of the simulated MAP data at 90 GHz (0.3 deg FWHM resolution smoothed) show that foreground effects on the correlation function are small compared with cosmic variance. However, the Galactic emission, even just from the region with |b| > 20 deg, significantly affects the topology of CMB anisotropy, causing a negative genus shift non-Gaussianity signal. Given the expected level of cosmic variance, this effect can be effectively reduced by subtracting existing Galactic foreground emission models from the observed data. IRAS and DIRBE far-infrared extragalactic sources have little effect on the CMB anisotropy. Radio point sources raise the amplitude of the correlation function considerably on scales below 0.5 deg. Removal of bright radio sources above a 5 \sigma detection limit effectively eliminates this effect. Radio sources also result in a positive genus curve asymmetry (significant at 2 \sigma) on 0.5 deg scales. Accurate radio point source data is essential for an unambiguous detection of CMB anisotropy non-Gaussianity on these scales. Non-Gaussianity of cosmological origin can be detected from the foreground-subtracted CMB anisotropy map at the 2 \sigma level if the measured genus shift parameter |\Delta\nu| >= 0.02 (0.04) or if the measured genus asymmetry parameter |\Delta g| >= 0.03 (0.08) on a 0.3 (1.0) deg FWHM scale.Comment: 26 pages, 7 figures, Accepted for Publication in Astrophysical Journal (Some sentences and figures modified

School Personnel Perceptions of Professional School Counselor Role and Function

The purpose of this research study was to examine the attitudes held by school-based administrators, teachers, and professional school counselors regarding ideal and actual roles of the professional school counselor. The survey instrument utilized in this research study, the PSCRFA, is grounded in the ASCA model and reflective of current school counseling ideology. This investigation determined if attitudes within and among the groups differed significantly along specific independent variables, such as age, gender, years of experience, school setting, student caseload, and educational level for school-based administrators, teachers, and professional school counselors working in an urban public school district in Hampton Roads, Virginia, as measured by the Professional School Counselor Role and Function Appraisal (PSCRFA). In addition, this study assisted in ascertaining the preferred level of engagement for professional school counselors within the school-wide counseling program. Quantitative statistical analyses were performed using SPSS ® Data Analysis System (IBM, 2012) to test for differences between and among groups of school-based administrators, teachers, and professional school counselors. Analysis of variance between ratings on degree of significance and degree of frequency revealed no statistically significant differences between administrators, teachers, and counselors along the three scales—except for significance ratings for Performance Standards. It was concluded that no significant association existed between the positions held by school personnel, their ratings on the importance of school counselor tasks, and ratings on how often tasks were performed. Overall, there was evidence of minimal agreement between participants\u27 beliefs of more significant performance standards being performed more frequently, as well as more significant counselor roles being performed more frequently. Within group differences were statistically significant for administrators and counselors with respect to degree of significance for work performed by professional school counselors. The results indicated that, overall, counselors most frequently reported higher ratings on the importance of program standards, performance standards, and counselor role. Overall scores for all three groups were lower for frequency than for importance, indicating that the school counselor\u27s level of functioning did not match the ideal performance levels preferred by school personnel

Assessing storage reliability of farm dams

This report provides information on a method to estimate the volume of water in a farm dam and to determine how long this water will last. During periods of low rainfall, dams with farmland catchments receive limited run-off. Alternative water sources or management strategies need to be considered before the water runs out. The methods provided in this report are intended to provide to the landholder an indication of water supply over short periods only (i.e. in the order of 4-20 weeks)

Extreme events and event size fluctuations in biased random walks on networks

Random walk on discrete lattice models is important to understand various types of transport processes. The extreme events, defined as exceedences of the flux of walkers above a prescribed threshold, have been studied recently in the context of complex networks. This was motivated by the occurrence of rare events such as traffic jams, floods, and power black-outs which take place on networks. In this work, we study extreme events in a generalized random walk model in which the walk is preferentially biased by the network topology. The walkers preferentially choose to hop toward the hubs or small degree nodes. In this setting, we show that extremely large fluctuations in event-sizes are possible on small degree nodes when the walkers are biased toward the hubs. In particular, we obtain the distribution of event-sizes on the network. Further, the probability for the occurrence of extreme events on any node in the network depends on its 'generalized strength', a measure of the ability of a node to attract walkers. The 'generalized strength' is a function of the degree of the node and that of its nearest neighbors. We obtain analytical and simulation results for the probability of occurrence of extreme events on the nodes of a network using a generalized random walk model. The result reveals that the nodes with a larger value of 'generalized strength', on average, display lower probability for the occurrence of extreme events compared to the nodes with lower values of 'generalized strength'

A low CMB variance in the WMAP data

We have estimated the CMB variance from the three-year WMAP data, finding a value which is significantly lower than the one expected from Gaussian simulations using the WMAP best-fit cosmological model, at a significance level of 98.7 per cent. This result is even more prominent if we consider only the north ecliptic hemisphere (99.8 per cent). Different analyses have been performed in order to identify a possible origin for this anomaly. In particular we have studied the behaviour of single radiometers and single year data as well as the effect of residual foregrounds and 1/f noise, finding that none of these possibilities can explain the low value of the variance. We have also tested the effect of varying the cosmological parameters, finding that the estimated CMB variance tends to favour higher values of $n_s$ than the one of the WMAP best-fit model. In addition, we have also tested the consistency between the estimated CMB variance and the actual measured CMB power spectrum of the WMAP data, finding a strong discrepancy. A possible interpretation of this result could be a deviation from Gaussianity and/or isotropy of the CMB.Comment: 13 pages, 5 figures. Some new tests added. Section 5 largely modified. Accepted for publication in MNRA

The time-evolution of bias

We study the evolution of the bias factor b and the mass-galaxy correlation coefficient r in a simple analytic model for galaxy formation and the gravitational growth of clustering. The model shows that b and r can be strongly time-dependent, but tend to approach unity even if galaxy formation never ends as the gravitational growth of clustering debiases the older galaxies. The presence of random fluctuations in the sites of galaxy formation relative to the mass distribution can cause large and rapidly falling bias values at high redshift.Comment: 4 pages, with 2 figures included. Typos corrected to match published ApJL version. Color figure and links at http://www.sns.ias.edu/~max/bias.html or from [email protected]

Gravitational Stability of Vortices in Bose-Einstein Condensate Dark Matter

We investigate a simple model for a galactic halo under the assumption that it is dominated by a dark matter component in the form of a Bose-Einstein condensate involving an ultra-light scalar particle. In particular we discuss the possibility if the dark matter is in superfluid state then a rotating galactic halo might contain quantised vortices which would be low-energy analogues of cosmic strings. Using known solutions for the density profiles of such vortices we compute the self-gravitational interactions in such halos and place bounds on the parameters describing such models, such as the mass of the particles involved.Comment: 17 pages, 4 figures, submitted to CQ

Wetland basins for saline drainage water disposal Bodallin and Elachbutting Catchments, eastern wheatbelt, Western Australia

This report provides an assessment of two large deep drainage schemes within the lower reaches of the Bodallin and Elachbutting Catchments nearby Merredin in Western Australia, wherein groups of isolated wetland basins have been utilised for evaporative saline drainage water disposal. In both cases, the storage capacity of the basins has been exceeded, leading to flooding and death of the surrounding native vegetation

Testing Gaussian random hypothesis with the cosmic microwave background temperature anisotropies in the three-year WMAP data

We test the hypothesis that the temperature of the cosmic microwave background is consistent with a Gaussian random field defined on the celestial sphere, using de-biased internal linear combination (DILC) map produced from the 3-year WMAP data. We test the phases for spherical harmonic modes with l <= 10 (which should be the cleanest) for their uniformity, randomness, and correlation with those of the foreground templates. The phases themselves are consistent with a uniform distribution, but not for l <= 5, and the differences between phases are not consistent with uniformity. For l=3 and l=6, the phases of the CMB maps cross-correlate with the foregrounds, suggestion the presence of residual contamination in the DLC map even on these large scales. We also use a one-dimensional Fourier representation to assemble a_lm into the \Delta T_l(\phi) for each l mode, and test the positions of the resulting maxima and minima for consistency with uniformity randomness on the unit circle. The results show significant departures at the 0.5% level, with the one-dimensional peaks being concentrated around \phi=180 degs. This strongly significant alignment with the Galactic meridian, together with the cross-correlation of DILC phases with the foreground maps, strongly suggests that even the lowest spherical harmonic modes in the map are significantly contaminated with foreground radiation.Comment: submitted to ApJL, one paragraph is added in Section 3 and some more in the Referenc