The X-ray Power Spectral Density Function and Black Hole Mass Estimate for the Seyfert AGN IC 4329a

We present the X-ray broadband power spectral density function (PSD) of the X-ray-luminous Seyfert IC 4329a, constructed from light curves obtained via Rossi X-ray Timing Explorer monitoring and an XMM-Newton observation. Modeling the 3-10 keV PSD using a broken power-law PSD shape, a break in power-law slope is significantly detected at a temporal frequency of 2.5(+2.5,-1.7) * 10^-6 Hz, which corresponds to a PSD break time scale T_b of 4.6(+10.1,-2.3) days. Using the relation between T_b, black hole mass M_BH, and bolometric luminosity as quantified by McHardy and coworkers, we infer a black hole mass estimate of M_BH = 1.3(+1.0,-0.3) * 10^8 solar masses and an accretion rate relative to Eddington of 0.21(+0.06,-0.10) for this source. Our estimate of M_BH is consistent with other estimates, including that derived by the relation between M_BH and stellar velocity dispersion. We also present PSDs for the 10-20 and 20-40 keV bands; they lack sufficient temporal frequency coverage to reveal a significant break, but are consistent with the same PSD shape and break frequency as in the 3-10 keV band.Comment: Accepted for publication in ApJ. 11 pages, 6 figures (5 color

The Price of Alcohol, Wife Abuse, and Husband Abuse

Alcohol consumption has been frequently linked to family violence. The purpose of this paper is to examine the direct relationship between the price of alcohol, which determines consumption, and violence towards spouses. The data come from the 1985 cross section and the 1985-1987 panel of the National Family Violence Survey. The 1985 data are a nationally representative sample while the panel oversamples violent individuals. Dichotomous indicators of severe violence towards wives and husbands are used. A reduced for violence equation is estimated, and individual-level fixed effects are used to control for unobserved characteristics in the panel. A consistent result that emerges from this paper is that an increase in the pure price of alcohol, as measured by a weighted average of the price of alcohol from beer, wine, and liquor, will serve to reduce severe violence aimed at wives. By contrast, the evidence on the propensity of an increase in the price of alcohol to lower violence towards husbands is mixed. When individual level characteristics are not controlled for, the price is not a predictor of violence towards men. However, once the individual traits are controlled for, a negative relationship between the price and violence emerges.

Circuit increases capability of hysteresis synchronous motor

Frequency and phase detector circuit enables a hysteresis synchronous motor to drive a load of given torque value at a precise speed determined by a stable reference. This technique permits driving larger torque loads with smaller motors and lower power drain

Barriers to Representation for Detained Immigrants Facing Deportation: Varick Street Detention Facility, A Case Study

There is an evolving crisis in the immigration courts and federal courts of appeals caused by the lack of quality representation for immigrants facing deportation. The problem is particularly acute for immigrants who are detained during their removal proceedings. As part of the Study Group on Immigrant Representation (Katzmann study group), the Subcommittee on Enhancing Mechanisms for Service Delivery undertook a case study of the institutional and legal barriers to quality legal representation for immigrants held at the Varick Street Detention Facility in New York City. Through this lens we hope to offer some useful insights into the core factors contributing to the immigration representation crisis, the institutional barriers that aggravate the crisis, and, finally, to propose a series of reforms to address the crisis

On time, frequency, and polar motion Quarterly reports, 1 Jan. - 30 Jun. 1969

Sudden changes in earth rotational acceleration and polar secular motio

Parameter Estimation and Confidence Regions in the Method of Light Curve Simulations for the Analysis of Power Density Spectra

The Method of Light Curve Simulations is a tool that has been applied to X-ray monitoring observations of Active Galactic Nuclei (AGN) for the characterization of the Power Density Spectrum (PDS) of temporal variability and measurement of associated break frequencies (which appear to be an important diagnostic for the mass of the black hole in these systems as well as their accretion state). It relies on a model for the PDS that is fit to the observed data. The determination of confidence regions on the fitted model parameters is of particular importance, and we show how the Neyman construction based on distributions of estimates may be implemented in the context of light curve simulations. We believe that this procedure offers advantages over the method used in earlier reports on PDS model fits, not least with respect to the correspondence between the size of the confidence region and the precision with which the data constrain the values of the model parameters. We plan to apply the new procedure to existing RXTE and XMM observations of Seyfert I galaxies as well as RXTE observations of the Seyfert II galaxy NGC 4945.Comment: 9 pages, 2 figures, accepted for publication in Ap

I Did What Last Night? Adolescent Risky Sexual Behaviors and Substance Abuse

Risky sexual behaviors by teenagers have shown to be strongly correlated with drug and alcohol consumption. The purpose of this study is to examine the question of whether alcohol and drug use increases the likelihood that teenagers will engage in four risky sexual behaviors: having sex, sex with multiple partners, sex without a condom, and sex without birth control. Two-stage least squares and a reduced form model are used to account for the potential endogeneity of substance use. The finding that alcohol consumption (as defined by either heavy drinking or drinking any amount) is unrelated to the probability of having sex is consistent with the findings of previous studies that also account for the potential endogeneity of alcohol consumption. The findings imply that the risky behaviors of sexually active teens, who may have made the decision long ago to become sexually active, might be altered through policies designed to reduce alcohol consumption.