2,745 research outputs found
Searching for Cooling Signatures in Strong Lensing Galaxy Clusters: Evidence Against Baryons Shaping the Matter Distribution in Cluster Cores
The process by which the mass density profile of certain galaxy clusters
becomes centrally concentrated enough to produce high strong lensing (SL)
cross-sections is not well understood. It has been suggested that the baryonic
condensation of the intra-cluster medium (ICM) due to cooling may drag dark
matter to the cores and thus steepen the profile. In this work, we search for
evidence of ongoing ICM cooling in the first large, well-defined sample of
strong lensing selected galaxy clusters in the range 0.1 < z < 0.6. Based on
known correlations between the ICM cooling rate and both optical emission line
luminosity and star formation, we measure, for a sample of 89 strong lensing
clusters, the fraction of clusters that have [OII]3727 emission in their
brightest cluster galaxy (BCG). We find that the fraction of line-emitting BCGs
is constant as a function of redshift for z > 0.2 and shows no statistically
significant deviation from the total cluster population. Specific star
formation rates, as traced by the strength of the 4000 angstrom break, D_4000,
are also consistent with the general cluster population. Finally, we use
optical imaging of the SL clusters to measure the angular separation, R_arc,
between the arc and the center of mass of each lensing cluster in our sample
and test for evidence of changing [OII] emission and D_4000 as a function of
R_arc, a proxy observable for SL cross-sections. D_4000 is constant with all
values of R_arc, and the [OII] emission fractions show no dependence on R_arc
for R_arc > 10" and only very marginal evidence of increased weak [OII]
emission for systems with R_arc < 10". These results argue against the ability
of baryonic cooling associated with cool core activity in the cores of galaxy
clusters to strongly modify the underlying dark matter potential, leading to an
increase in strong lensing cross-sections.Comment: 9 Pages, 5 Figures, 1 Tabl
Leading, educating, and inspiring LIS professionals to embrace accessibility for a resilient future
The COVID years (2020-2021) have put the issues of disability and accessibility in the spotlight. Social interactions, employment, studies, and day-to-day activities for some people with disabilities have become increasingly more challenging than before; and yet, others have found opportunity and even relief in working from home, having a chance to avoid the grueling commute and inaccessible physical environments, often associated with workplaces. The pandemic and remote engagements have thus highlighted disparities within the disabled community itself: those with comfortable living conditions, information literacy skills, and stable internet access fared exceedingly better than individuals lacking these conditions. People with disabilities in all LIS constituent groups have been affected: students, librarians, library users, faculty, and academic staff. This has shown the need for building resilience and intensifying discussion on the importance of accessibility. This session will bring together over a dozen educators from American and Canadian LIS programs and include five presentations accompanied by hands-on interactive activities. After a brief introduction (5 min), each group of presenters will introduce their topics (30-35 min) and then engage the audience in a series of activities that they have prepared (40 min). Participants will reconvene for the general discussion (10-15 min). Cahill, Adkins, and Bushman will review the ways in which LIS courses in youth services address programs for young children with disabilities. Following the talk, they will facilitate the collaborative scrutiny of syllabi from LIS youth services courses. They will encourage participants to collectively come up with solutions, changes, and improvements and show their alignments with ALA Core Competences and COA Standards for Accreditation. Copeland, Mallary, and Thompson will focus on the training of LIS professionals that helps them embrace accessibility by using scenarios for inclusive hiring practices. They will offer a lesson plan for preparing future LIS managers and leaders for the equitable handling of job interviews, inclusive job advertising, and onboarding after hiring. Participants will learn to design training scenarios related to teaching students about inclusive communicative practices. Focusing on the potential of libraries to provide “non-pharmacological interventions” that improve the lives of people living with dementia and their care partners, Dickey will help participants explore the ways to prepare LIS students for supporting these user groups. Participants will brainstorm practical suggestions for fostering accessibility when people with dementia are concerned and discover resources for leadership and advocacy. Hill and Wong will zero in on everyday choices made by LIS educators in their course design that can improve accessibility in learning, including policies, learning materials, and considerations of diversity in establishing “norms.” Participants will leave with a checklist of practices for accessibility audit in their courses. Farmer will take up the topic of collaboration with disability support service providers (DSSP). Building off the lived experiences of individuals with Autism Spectrum Disorder (ASD), participants will learn several strategies for successful collaboration with DSSP. The SIG session will end with the general discussion of how the aforementioned aspects are affected during world health emergencies and what it means for the future of accessibility
Analisis Perkembangan Kemampuan Keuangan Daerah pada Pemerintah Provinsi Sulawesi Utara Tahun Anggaran 2014-2018
This study aims to determine how the development of regional financial capability in the North Sulawesi provincial government from its level of independence, level of dependency, decentralization ratio, and financial growth. The main characteristic of the region's ability to organize its government is the ability in its finances to finance the administration of the regional government. This type of research is qualitative research. Descriptive method is an analytical method used in this thesis research, that is every data - data obtained, analyzed based on theories relevant to the problem to be discussed to obtain the results of the analysis which is then concluded and provides advice. The results of descriptive analysis of the North Cellebes Province LRA APBD data show that from 2014 to 2018, the Regional Original Revenue development is still lacking, has not experienced a significant increase because Transfer Funds still dominate the Regional Revenue of North Cellebes Province. The conclusion is that there has been an improvement even though it is lacking, but based on the calculation of the financial ratios the Financial Ability is still in the near-able valuation
The Mass Distribution of the Strong Lensing Cluster SDSS J1531+3414
We present the mass distribution at the core of SDSS J1531+3414, a
strong-lensing cluster at z=0.335. We find that the mass distribution is well
described by two cluster-scale halos with a contribution from cluster-member
galaxies. New HST observations of SDSS J1531+3414 reveal a signature of ongoing
star formation associated with the two central galaxies at the core of the
cluster, in the form of a chain of star forming regions at the center of the
cluster. Using the lens model presented here, we place upper limits on the
contribution of a possible lensed image to the flux at the center region, and
rule out that this emission is coming from a background source.Comment: 8 pages, 5 figures; Submitted to Ap
Hydrodynamics and the Detection of the QCD Axial Anomaly in Heavy Ion Collisions
We consider the experimental implications of the axial current triangle
diagram anomaly in a hydrodynamic description of high density QCD. We propose a
signal of an enhanced production of spin-excited hadrons in the direction of
the rotation axis in off-central heavy ion collisions.Comment: 15 pages, 19 figures; v2: refs added, minor changes to the plots; v3,
comments adde
Asymmetric Surface Brightness Structure of Caustic Crossing Arc in SDSS J1226+2152: A Case for Dark Matter Substructure
We study the highly magnified arc SGAS J122651.3+215220 caused by a
star-forming galaxy at crossing the lensing caustic cast by the
galaxy cluster SDSS J1226+2152 (), using Hubble Space Telescope
observations. We report in the arc several asymmetric surface brightness
features whose angular separations are a fraction of an arcsecond from the
lensing critical curve and appear to be highly but unequally magnified image
pairs of underlying compact sources, with one brightest pair having clear
asymmetry consistently across four filters. One explanation of unequal
magnification is microlensing by intracluster stars, which induces independent
flux variations in the images of individual or groups of source stars in the
lensed galaxy. For a second possibility, intracluster dark matter subhalos
invisible to telescopes effectively perturb lensing magnifications near the
critical curve and give rise to persistently unequal image pairs. Our modeling
suggests, at least for the most prominent identified image pair, that the
microlensing hypothesis is in tension with the absence of notable asymmetry
variation over a six-year baseline, while subhalos of -- anticipated from structure formation with Cold Dark
Matter typically produce stationary and sizable asymmetries. We judge that
observations at additional times and more precise lens models are necessary to
stringently constrain temporal variability and robustly distinguish between the
two explanations. The arc under this study is a scheduled target of a
Director's Discretionary Early Release Science program of the James Webb Space
Telescope, which will provide deep images and a high-resolution view with
integral field spectroscopy.Comment: New version accepted by MNRAS; 18 pages including references and
appendices, 13 figures and 4 tables; major revision of Sec. 3.2 and Figure 4
presenting improved data analysis; original conclusion strengthened
Manado Christian Community Center. Arsitektur Simbolisme
Kota Manado adalah sebuah kota yang sedang mengalami pertumbuhan dan perkembangan yang cukup pesat. Kota Manado kini berkembang menjadi sebuah kota maju dan semakin berkembang. Hal ini ditandai dengan makin banyaknya investor menanam modalnya di wilayah Kota Manado. Dengan demikian tentu saja hal tersebut memacu roda industri didaerah ini yang ujungnya bermuara kepada pembukuan lapangan pekerjaan baik sektor formal maupun informal. Hal ini tentu saja mengundang banyak kaum urbanis yang berbondong-bondong tiap tahunnya untuk datang ke Kota Manado. Jumlah penduduk yang meningkat tiap tahunnya tentu saja membutuhkan fasilitas umum, antara lain adalah fasilitas kesehatan, fasilitas olahraga, pusat perbelanjaan, fasilitas transportasi dan fasilitas institusi Pendidikan (TK, SD, SLTP, SLTA, Perguruan Tinggi). Namum belum adanya suatu fasilitas umum yang berkaitan dengan aspek sosial-spiritual. Manado Christian Community Center merupakan sebuah tempat/wadah yang menampung aktifitas masyarakat Kristen dalam aspek sosial, rohani-edukatif, dan juga rekreatif. Sebuah community center didalamnya terdiri dari perpustakaan umum, museum rohani mini, studio music, internet caffe, convention hall, amphitheater dan mungkin beberapa fasilitas publik lainnya yang terangkum dalam suatu kawasan yang dilengkapi oleh penataan ruang luar yang baik. Dengan mengambil tema Arsitektur Simbolisme, akan dibuat Christian Community Center yang cukup berbeda dengan Christian Community Center yang lainnya, dimana bangunan ini akan mengacuh pada simbol-simbol kekristenan dengan estetika interior dan strukturnya akan sangat menarik dan memperjelas fungsi dari bangunan tersebut. Begitu pula dengan karya-karya arsitektural yang juga merupakan kumpulan dari elemen-elemen pembentuk yang memiliki suatu makna/arti dapat menjadikan Manado Christian Community Center sebagai tempat yang mewadahi aktifitas pertemuan, berkomunikasi, dan bertukar pikiran, saling memberikan informasi dan pengetahuan kekristenan, serta saling menunjang dengan fungsi lainnya untuk menjadikan Manado Christian Community Center sebagai sarana yang menunjang ifrastruktur perkembangan Kota Manado
An Accurate Determination of the Exchange Constant in Sr_2CuO_3 from Recent Theoretical Results
Data from susceptibility measurements on Sr_2CuO_3 are compared with recent
theoretical predictions for the magnetic susceptibility of the
antiferromagnetic spin-1/2 Heisenberg chain. The experimental data fully
confirms the theoretical predictions and in turn we establish that Sr_2CuO_3
behaves almost perfectly like a one-dimensional antiferromagnet with an
exchange coupling of J = 1700^{+150}_{-100}K.Comment: revised and reformatted paper with new title to appear in Phys. Rev B
(Feb.1996). 3 pages (revtex) with 3 embedded figures (macro included). A
complete postscript file is available from
http://fy.chalmers.se/~eggert/expsusc.ps or by request from
[email protected]
Gravitational lensing reveals ionizing ultraviolet photons escaping from a distant galaxy
During the epoch of reionisation, neutral gas in the early Universe was
ionized by hard ultraviolet radiation emitted by young stars in the first
galaxies. To do so, ionizing ultraviolet photons must escape from the host
galaxy. We present Hubble Space Telescope observations of the gravitationally
lensed galaxy PSZ1-ARC G311.6602-18.4624, revealing bright, multiply-imaged
ionizing photon escape from a compact star-forming region through a narrow
channel in an optically thick gas. The gravitational lensing magnification
shows how ionizing photons escape this galaxy, contributing to the
re-ionization of the Universe. The multiple sight lines to the source probe
absorption by intergalactic neutral hydrogen on scales of no more than a few
hundred, perhaps even less than ten, parsec.Comment: 17 pages, 9 figures. Published in Scienc
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