B-R Colors of Globular Clusters in NGC 6166 (A2199)

We have analysed new R-band photometry of globular clusters in NGC 6166, the cD galaxy in the cooling flow cluster A2199. In combination with the earlier B photometry of Pritchet \& Harris (1990), we obtain B$-$R colours for $\sim$ 40 globular clusters in NGC 6166. The mean B$-$R is 1.26 $\pm$ 0.11, corresponding to a mean [Fe/H] = $-$1 $\pm$ 0.4. Given that NGC 6166 is one of the most luminous cD galaxies studied to date, our result implies significant scatter in the relationship between mean cluster [Fe/H] and parent galaxy luminosity. We obtain a globular cluster specific frequency of S$_N$ $\sim$ 9, with a possible range between 5 and 18. This value is inconsistent with the value of S$_N$ $\leq$ 4 determined earlier by Pritchet \& Harris (1990) from B-band photometry, and we discuss possible reasons for the discrepancy. Finally, we reassess whether or not cooling flows are an important mechanism for forming globular clusters in gE/cD galaxies.Comment: 8 pages, uuencoded, gzipped tar file with latex file, 6 figures (Fig 1 omitted because of size), and mn.sty file. Figures will be embedded into the postscript file. Accepted (March 1996) for publication in MNRA

Transverse instability and its long-term development for solitary waves of the (2+1)-Boussinesq equation

The stability properties of line solitary wave solutions of the (2+1)-dimensional Boussinesq equation with respect to transverse perturbations and their consequences are considered. A geometric condition arising from a multi-symplectic formulation of this equation gives an explicit relation between the parameters for transverse instability when the transverse wavenumber is small. The Evans function is then computed explicitly, giving the eigenvalues for transverse instability for all transverse wavenumbers. To determine the nonlinear and long time implications of transverse instability, numerical simulations are performed using pseudospectral discretization. The numerics confirm the analytic results, and in all cases studied, transverse instability leads to collapse.Comment: 16 pages, 8 figures; submitted to Phys. Rev.

A computer operated mass spectrometer system

Digital computer system for processing mass spectrometer output dat

Computer control of mass analyzers

Digital computer control of mass spectrometer

Forensic implications of the variation in morphology of marginal serrations on the teeth of the great white shark

The teeth of the Great White Shark have been examined to ascertain whether there is any commonality in the arrangement or number of the marginal serrations (peaks) or, indeed, whether individual sharks have a unique pattern of shapes or size of the peaks. The teeth of the White Shark are characteristic in size and shape with serrations along almost the entire mesial and distal margins. This study has revealed no consistent pattern of size or arrangement of the marginal serrations that was sufficiently characteristic within an individual shark to serve as a reliable index of identification of a tooth as originating from that particular shark. Nonetheless, the serrations are sufficiently distinctive to enable the potential identification of an individual tooth as having been the cause of a particular bitemark. This record was migrated from the OpenDepot repository service in June, 2017 before shutting down

Allometric relationships of the dentition of the great White Shark, Carcharodon carcharias, in forensic investigations of shark attacks

As a result of a systematic morphometric study of shark dentitions, a system of notation for describing the location of shark teeth has been developed and is proposed as a standard to be adopted for use in similar studies in the future. The macroscopic morphology of White Shark teeth has been characterised in order to gain quantitative data which might assist in identification of these sharks from bite marks on victims or objects or from shark carcasses. Using these data, a nomogram has been developed which can be used to estimate the body length of a White Shark from measurements of tooth or bite mark morphology. An example of the forensic application of such allometric data is provided as it applied to a recent fatal attack on a diver by a White Shark. This record was migrated from the OpenDepot repository service in June, 2017 before shutting down

Quantitative forensic evaluation of bite marks with the aid of a shape analysis computer program: Part 1; the development of 'SCIP' and the Similarity Index

Bite marks left on human tissue and bitten material have become an important aspect of scientific evidence used for the conviction or acquittal of a suspect. Expert opinion has often been based on subjective comparisons rather than any objective metrical analysis and many experts will agree that there is a need to employ additional comparative tests to achieve unbiased objectivity in their investigation. In this study, an interactive shape analysis computer program ('SCIP' - Shape Comparison Interactive Program) has been employed in an attempt to derive experimentally a quantitative comparison, in the form of a Similarity Index (S.I.), between the 'offender's' teeth and the bite marks produced on a standard flat wax form. The S.I. values obtained using 'SCIP' were evaluated in a variety of experimental bite mark situations. It was found that in no case could the S.I. values produced by comparison of the bite mark with the dental casts from non-perpetrators be confused with the much lower S.I. from comparison of the bite mark with the dental cast of the perpetrator. The use of the Similarity Index derived using the 'SCIP' program is recommended as a simple, accurate and objective means of comparing bite marks in suitable forensic cases. This record was migrated from the OpenDepot repository service in June, 2017 before shutting down

No Increase of the Red-Giant-Branch Tip Luminosity Toward the Center of M31

We present observations with the Hubble Space Telescope Wide Field Planetary Camera 2 of three fields centered on super-metal-rich globular clusters in the bulge of M31. Our (I,V-I) color-magnitude diagrams reach as faint as I ~ 26.5 mag and clearly reveal the magnitude of the first ascent red giant branch (RGB) tip. We find that the apparent I magnitude of the RGB tip does not become brighter near the center of M31 as concluded by previous investigators. Our observations and artificial star experiments presented in this study strongly support the idea that previous very bright stars were likely the result of spurious detections of blended stars due to crowding in lower resolution images. On the contrary, our observations indicate that, at a mean projected galactocentric distance of 1.1 kpc, the RGB tip is some 1.3 magnitudes fainter than it is at 7 kpc. An analysis of this difference in RGB tip magnitude suggests that the M31 bulge stellar population has a mean metallicity close to that of the Sun.Comment: Accepted for publication in ApJ, June 20, 1999 issu

The relationship between the surface pressure spectrum and transverse velocity spectrum in a Rapid-distortion theory model of trailing edge noise

Accurate jet-surface interaction noise prediction remains an important aspect of the aircraft design process. This is particularly true for the next generation aircraft configurations, one of which could see the exhaust system tightly integrated to the airframe. Use of Rapid- distortion theory of turbulence (RDT) to determine the radiated sound represents one such approach to model the sound generation/propagation process. Recent work on the application of RDT to the canonical problem of a jet flow interacting with a flat plate trailing edge gave accurate predictions across the frequency and acoustic Mach number range. In this paper we ascertain whether an RDT based model that uses the unsteady surface pressure spectrum as the source term can also be utilized to determine accurate edge noise predictions. Surface pressure based models have been widely used in the Amiet formulation of trailing edge noise. The upstream boundary condition in the RDT formulation enters via a streamwise convected quantity, ω ̃c(τ − y1/U(yT ), yT ), that is an arbitrary function of its arguments. But since the pressure fluctuation possesses an upstream asymptote that decays algebraically faster than curl of the out-of-plane vorticity fluctuation in the local hydrodynamic relation given by Eq. 3.9 in Goldstein, Leib & Afsar (J. Fluid Mech., vol. 824, pp. 477-512, 2017), this latter relation cannot be used to determine the surface pressure near the trailing edge. In this paper we show to obtain this relation using an inversion of Fourier transforms similar to that used in our earlier paper Goldstein, Afsar & Leib (J. Fluid Mech., vol. 736, pp. 532-569, 2013). The relation we obtain shows how the surface pressure spectrum can therefore be related to the velocity fluctuation correlation function