9 research outputs found
Models for the Magnitude-Distribution of Brightest Cluster Galaxies
The brightest, or first-ranked, galaxies (BCGs) in rich clusters show a very
small dispersion in luminosity, making them excellent standard candles. This
small dispersion has raised questions about the nature of BCGs. Are they simply
the extremes of normal galaxies formed via a stochastic process, or do they
belong to a special class of atypical objects? Arguments have been proposed on
both sides of the debate. Bhavsar (1989) suggested that the distribution in
magnitudes can only be explained by a two-population model. Thus, a new
controversy has arisen. Do first-ranked galaxies consist of one or two
populations of objects? We examine an older and newer data set and present our
results. Two-population models do better than do one-population models. A
simple model where a random boost in the magnitude of a fraction of bright
normal galaxies forms a class of atypical galaxies best describes the observed
distribution of BCG magnitudes. Moreover, the parameters that describe the
model and the parameters of the boost have a strong physical basis.Comment: Abstract submitted to AAS. Paper (6 pages, 4 figs.) to be published
in the MNRAS; uses mn.st
A Sense of Belonging
National Collegiate Honors Council President delivers his address at the NCHC’s 2021 conference, describing that, despite the privileges he has chosen and enjoyed, expressions of otherness have led to feelings of estrangement. Considering the question of how to face this challenge in honors, the author emphasizes the imperative of creating a sense of belonging for every student
A catalog of Nearby Poor Clusters of Galaxies
A catalog of 732 optically selected, nearby poor clusters of galaxies
covering the entire sky north of declination is presented. The
poor clusters, called WBL clusters, were identified as concentrations of 3 or
more galaxies with photographic magnitudes brighter than 15.7, possessing a
galaxy surface overdensity of . These criteria are consistent with
those used in the identification of the original Yerkes poor clusters, and this
new catalog substantially increases the sample size of such objects. These poor
clusters cover the entire range of galaxy associations up to and including
Abell clusters, systematically including poor and rich galaxy systems spanning
over three orders of magnitude in the cluster mass function. As a result, this
new catalog contains a greater diversity of richness and structures than other
group catalogs, such as the Hickson or Yerkes catalogs. The information on
individual galaxies includes redshifts and cross-references to other galaxy
catalogs. The entries for the clusters include redshift (where available) and
cross-references to other group and cluster catalogs.Comment: 27 pages, 7 figures, + one 20-page landscape table, accepted for
publication in A
Professional Transitions in Honors: Challenges, Opportunities, and Tips
Authors reflect on ways that honors practitioners have experienced various professional transitions and provide insights to help others successfully manage such changes.
Honors transitions are inevitable. Many of us in honors, for example, have relocated from other disciplines, moving from the prescribed boundaries of our academic areas to the diverse and challenging demands of honors, quickly learning new leadership skills and approaches to navigating challenges and prospects within and outside our institutions. Some of us have relocated to different institutions; some have negotiated growth from programs to colleges; some have advanced to positions in higher administration; some have witnessed changes in directors or deans; some have needed to adjust to the rapid succession of top administrators and their assorted agendas; some have retired. With creative approaches to change, such shifts to new faces, leadership styles, program ideas, and professional priorities can become opportunities rather than obstacles in our professional development in honors. The authors of this piece represent honors professionals who have experienced various transitions, and we offer our reflections and tips to help others in our field to manage such changes successfully
Teaching from the Heart
This essay is an invitation to consider a paradigm shift in the academy, one that allows and encourages us to bring our whole selves into our teaching and professional lives. I describe a set of values that permits and encourages the expression of a rigorously examined inner self in harmony with the traditional expression of our scholarly selves in our curricula and classrooms. Drawing from lessons that have defined my aspirations as a teacher, I challenge honors educators to lead the way in courageously examining our pedagogical approaches and to teach from our hearts