UNLV Contemporary Jazz Ensemble

list of performers and performances

UNLV Jazz Ensemble II and III

Program listing performers and works performe

The UNLV Jazz Ensemble II and III

Program listing performers and works performe

Smooth critical points of planar harmonic mappings

In a work in 1992, Lyzzaik studies local properties of light harmonic mappings. More precisely, he classifies their critical points and accordingly studies their topological and geometrical behaviours. We will focus our study on smooth critical points of light harmonic maps. We will establish several relationships between miscellaneous local invariants, and show how to connect them to Lyzzaik's models. With a crucial use of Milnor fibration theory, we get a fundamental and yet quite unexpected relation between three of the numerical invariants, namely the complex multiplicity, the local order of the map and the Puiseux pair of the critical value curve. We also derive similar results for a real and complex analytic planar germ at a regular point of its Jacobian level-0 curve. Inspired by Whitney's work on cusps and folds, we develop an iterative algorithm computing the invariants. Examples are presented in order to compare the harmonic situation to the real analytic one.Comment: 36 pages, 5 figure

Stability of an Ultra-Relativistic Blast Wave in an External Medium with a Steep Power-Law Density Profile

We examine the stability of self-similar solutions for an accelerating relativistic blast wave which is generated by a point explosion in an external medium with a steep radial density profile of a power-law index > 4.134. These accelerating solutions apply, for example, to the breakout of a gamma-ray burst outflow from the boundary of a massive star, as assumed in the popular collapsar model. We show that short wavelength perturbations may grow but only by a modest factor <~ 10.Comment: 12 pages, 3 figures, submitted to Physical Review

Las Vegas Academy Jazz Band III: A Celebration of Black History Month

Program listing performers and works performed

Measuring the 3D Clustering of Undetected Galaxies Through Cross Correlation of their Cumulative Flux Fluctuations from Multiple Spectral Lines

We discuss a method for detecting the emission from high redshift galaxies by cross correlating flux fluctuations from multiple spectral lines. If one can fit and subtract away the continuum emission with a smooth function of frequency, the remaining signal contains fluctuations of flux with frequency and angle from line emitting galaxies. Over a particular small range of observed frequencies, these fluctuations will originate from sources corresponding to a series of different redshifts, one for each emission line. It is possible to statistically isolate the fluctuations at a particular redshift by cross correlating emission originating from the same redshift, but in different emission lines. This technique will allow detection of clustering fluctuations from the faintest galaxies which individually cannot be detected, but which contribute substantially to the total signal due to their large numbers. We describe these fluctuations quantitatively through the line cross power spectrum. As an example of a particular application of this technique, we calculate the signal-to-noise ratio for a measurement of the cross power spectrum of the OI(63 micron) and OIII(52 micron) fine structure lines with the proposed Space Infrared Telescope for Cosmology and Astrophysics. We find that the cross power spectrum can be measured beyond a redshift of z=8. Such observations could constrain the evolution of the metallicity, bias, and duty cycle of faint galaxies at high redshifts and may also be sensitive to the reionization history through its effect on the minimum mass of galaxies. As another example, we consider the cross power spectrum of CO line emission measured with a large ground based telescope like CCAT and 21-cm radiation originating from hydrogen in galaxies after reionization with an interferometer similar in scale to MWA, but optimized for post-reionization redshifts.Comment: 21 pages, 6 figures; Replaced with version accepted by JCAP; Added an example of cross correlating CO line emission and 21cm line emission from galaxies after reionizatio

Event-Horizon-Telescope Evidence for Alignment of the Black Hole in the Center of the Milky Way with the Inner Stellar Disk

Observations of the black hole in the center of the Milky Way with the Event Horizon Telescope at 1.3 mm have revealed a size of the emitting region that is smaller than the size of the black-hole shadow. This can be reconciled with the spectral properties of the source, if the accretion flow is seen at a relatively high inclination (50-60 degrees). Such an inclination makes the angular momentum of the flow, and perhaps of the black hole, nearly aligned with the angular momenta of the orbits of stars that lie within 3 arcsec from the black hole. We discuss the implications of such an alignment for the properties of the black hole and of its accretion flow. We argue that future Event-Horizon-Telescope observations will not only refine the inclination of Sgr A* but also measure precisely its orientation on the plane of the sky.Comment: To appear in the Astrophysical Journa