The SBF Survey of Galaxy Distances. I. Sample Selection, Photometric Calibration, and the Hubble Constant

We describe a program of surface brightness fluctuation (SBF) measurements for determining galaxy distances. This paper presents the photometric calibration of our sample and of SBF in general. Basing our zero point on observations of Cepheid variable stars, we find that the absolute SBF magnitude in the Kron-Cousins I band correlates well with the mean (V-I)o color of a galaxy according to M_Ibar = (-1.74 +/- 0.07) + (4.5 +/- 0.25) [ (V-I)o - 1.15 ] for 1.0 < (V-I) < 1.3. This agrees well with theoretical estimates from stellar population models. Comparisons between SBF distances and a variety of other estimators, including Cepheid variable stars, the Planetary Nebula Luminosity Function (PNLF), Tully-Fisher (TF), Dn-sigma, SNII, and SNIa, demonstrate that the calibration of SBF is universally valid and that SBF error estimates are accurate. The zero point given by Cepheids, PNLF, TF (both calibrated using Cepheids), and SNII is in units of Mpc; the zero point given by TF (referenced to a distant frame), Dn-sigma and SNIa is in terms of a Hubble expansion velocity expressed in km/s. Tying together these two zero points yields a Hubble constant of H_0 = 81 +/- 6 km/s/Mpc. As part of this analysis, we present SBF distances to 12 nearby groups of galaxies where Cepheids, SNII, and SNIa have been observed.Comment: 29 pages plus 8 figures; LaTeX (AASTeX) uses aaspp4.sty (included); To appear in The Astrophysical Journal, 1997 February 1 issue; Compressed PostScript available from ftp://mars.tuc.noao.edu/sbf

Evidence for (and Against) Progenitor Bias in the Size Growth of Compact Red Galaxies

Most massive passive galaxies are compact at high redshifts, but similarly compact massive galaxies are rare in the local universe. The most common interpretation of this phenomenon is that massive galaxies have grown in size by a factor of about five since redshift z=2. An alternative explanation is that recently quenched massive galaxies are larger (a "progenitor bias"). In this paper we explore the importance of progenitor bias by looking for systematic differences in the stellar populations of compact early-type galaxies in the DEEP2 survey as a function of size. Our analysis is based on applying the statistical technique of bootstrap resampling to constrain differences in the median ages of our samples and to begin to characterize the distribution of stellar populations in our co-added spectra. The light-weighted ages of compact early-type galaxies at redshifts 0.5 < z < 1.4 are compared to those of a control sample of larger galaxies at similar redshifts. We find that massive compact early-type galaxies selected on the basis of red color and high bulge-to-total ratio are younger than similarly selected larger galaxies, suggesting that size growth in these objects is not driven mainly by progenitor bias, and that individual galaxies grow as their stellar populations age. However, compact early-type galaxies selected on the basis of image smoothness and high bulge-to-total ratio are older than a control sample of larger galaxies. Progenitor bias will play a significant role in defining the apparent size changes of early-type galaxies if they are selected on the basis of the smoothness of their light distributions.Comment: 39 pages, 10 figures. Astrophysical Journal (in press

A Hubble Space Telescope Snapshot Survey of Dynamically Close Galaxy Pairs in the CNOC2 Redshift Survey

We compare the structural properties of two classes of galaxies at intermediate redshift: those in dynamically close galaxy pairs, and those which are isolated. Both samples are selected from the CNOC2 Redshift Survey, and have redshifts in the range 0.1 < z <0.6. Hubble Space Telescope WFPC2 images were acquired as part of a snapshot survey, and were used to measure bulge fraction and asymmetry for these galaxies. We find that paired and isolated galaxies have identical distributions of bulge fractions. Conversely, we find that paired galaxies are much more likely to be asymmetric (R_T+R_A >= 0.13) than isolated galaxies. Assuming that half of these pairs are unlikely to be close enough to merge, we estimate that 40% +/- 11% of merging galaxies are asymmetric, compared with 9% +/- 3% of isolated galaxies. The difference is even more striking for strongly asymmetric (R_T+R_A >= 0.16) galaxies: 25% +/- 8% for merging galaxies versus 1% +/- 1% for isolated galaxies. We find that strongly asymmetric paired galaxies are very blue, with rest-frame B-R colors close to 0.80, compared with a mean (B-R)_0 of 1.24 for all paired galaxies. In addition, asymmetric galaxies in pairs have strong [OII]3727 emission lines. We conclude that close to half of the galaxy pairs in our sample are in the process of merging, and that most of these mergers are accompanied by triggered star formation.Comment: Accepted for publication in the Astronomical Journal. 40 pages, including 15 figures. For full resolution version, please see http://www.trentu.ca/physics/dpatton/hstpairs

Applying dissipative dynamical systems to pseudorandom number generation: Equidistribution property and statistical independence of bits at distances up to logarithm of mesh size

The behavior of a family of dissipative dynamical systems representing transformations of two-dimensional torus is studied on a discrete lattice and compared with that of conservative hyperbolic automorphisms of the torus. Applying dissipative dynamical systems to generation of pseudorandom numbers is shown to be advantageous and equidistribution of probabilities for the sequences of bits can be achieved. A new algorithm for generating uniform pseudorandom numbers is proposed. The theory of the generator, which includes proofs of periodic properties and of statistical independence of bits at distances up to logarithm of mesh size, is presented. Extensive statistical testing using available test packages demonstrates excellent results, while the speed of the generator is comparable to other modern generators.Comment: 6 pages, 3 figures, 3 table

The Weiss conjecture on admissibility of observation operators for contraction semigroups

We prove the conjecture of George Weiss for contraction semigroups on Hilbert spaces, giving a characterization of infinite-time admissible observation functionals for a contraction semigroup, namely that such a functional C is infinite-time admissible if and only if there is an M > 0 such that parallel to IC(sI - A)(-1)parallel to less than or equal to M/root Re s for all s in the open right half-plane. Here A denotes the infinitesimal generator of the semigroup. The result provides a simultaneous generalization of several celebrated results from the theory of Hardy spaces involving Carleson measures and Hankel operators

Особистісні трансформації складових поведінкового компонента професійної діяльності правоохоронців

The author of the article has provided the results of the study of the features of personal transformations of the elements of behavioral component of law enforcement officers’ professional activity at the stage of training in higher educational institutions with specific learning conditions. The interdependent elements of behavioral component of a law enforcement officer’s professional activity have been singled out, namely: the adaptive potential of an individual, skills and behavioral self-regulation styles, individual and business qualities, mechanisms of psychological protection and coping-behavior strategies. The author has diagnosed the features of strategies and models of coping behavior of law enforcement officers at different stages of professional training. So, in difficult life situations it is typical for freshmen to come into contact with others for decision-making. Despite this, they are able to take responsibility and solve problems independently, although they still need support from others. Second-year students tend to work together to achieve mutual goals that coincide and to avoid the risk of failure due to long-term analysis of solution options and possible consequences, they are prone to re-insurance and cautious actions. Third-year students seek support from others (family, friends, colleagues), have the ability to solve problematic, difficult situations with other people, are able to cooperate and behave combining inner strength and politeness to the environment. MA students use practically the same with third-year students a set of models of coping behavior, search for social support and interaction with people. However, they are more prone to cautious actions and weighed decisions than third-year students. It has been determined that law enforcement officers at the stage of professional training are least of all inclined to use passive and asocial coping strategies. Thus, freshmen in difficult situations will not demonstrate caution and aggression, second-year students will not avoid difficulties and behave in asocial way, third-year students are also less likely to engage in antisocial and aggressive actions, and MA students are less likely to act aggressively and avoid solving problems.Представлены результаты исследования особенностей личностных трансформаций составляющих поведенческого компонента профессиональной деятельности правоохранителей на этапе обучения в учреждениях высшего образования со специфическими условиями обучения. Выделены взаимосвязанные составляющие поведенческого компонента профессиональной деятельности правоохранителя. Диагностировано, что в сложных ситуациях курсанты 1 и 3 курсов обучения используют достаточно широкий спектр просоциальных и активных стратегий копинг-поведения. Выяснено, что курсанты 2 курса обучения и слушатели магистратуры наряду с просоциальными действиями склонны к пассивному копинг-поведению.Подано результати дослідження особливостей особистісних трансформацій складових поведінкового компонента професійної діяльності правоохоронців на етапі навчання у закладах вищої освіти зі специфічними умовами навчання. Виокремлено взаємозалежні складові поведінкового компонента професійної діяльності правоохоронця. Діагностовано, що у складних ситуаціях курсанти 1 та 3 курсів навчання використовують досить широкий спектр просоціальних та активних стратегій копінг-поведінки. З’ясовано, що курсанти 2 курсу навчання та слухачі магістратури разом із просоціальними діями схильні до пасивної копінг-поведінки