A spectroscopic study of the globular Cluster NGC 4147

Indexación: Web of ScienceWe present the abundance analysis for a sample of 18 red giant branch stars in the metal-poor globular cluster NGC 4147 based on medium- and high-resolution spectra. This is the first extensive spectroscopic study of this cluster. We derive abundances of C, N, O, Na, Mg, Al, Si, Ca, Ti, Cr, Fe, Ni, Y, Ba, and Eu. We find a metallicity of [Fe/H] = -1.84 +/- 0.02 and an alpha-enhancement of +0.38 +/- 0.05 (errors on the mean), typical of halo globular clusters in this metallicity regime. A significant spread is observed in the abundances of light elements C, N, O, Na, and Al. In particular, we found an Na-O anticorrelation and Na-Al correlation. The cluster contains only similar to 15 per cent of stars that belong to the first generation (Na-poor and O-rich). This implies that it suffered a severe mass-loss during its lifetime. Its [Ca/Fe] and [Ti/Fe] mean values agree better with the Galactic halo trend than with the trend of extragalactic environments at the cluster metallicity. This possibly suggests that NGC 4147 is a genuine Galactic object at odd with what claimed by some author that proposed the cluster to be member of the Sagittarius dwarf galaxy. An antirelation between the light s-process element Y and Na may also be present.https://academic.oup.com/mnras/article-lookup/doi/10.1093/mnras/stw114

Abundance ratios of red giants in low mass ultra faint dwarf spheroidal galaxies

Low mass dwarf spheroidal galaxies are key objects for our understanding of the chemical evolution of the pristine Universe and the Local Group of galaxies. Abundance ratios in stars of these objects can be used to better understand their star formation and chemical evolution. We report on the analysis of a sample of 11 stars belonging to 5 different ultra faint dwarf spheroidal galaxies (UfDSph) based on X-Shooter spectra obtained at the VLT. Medium resolution spectra have been used to determine the detailed chemical composition of their atmosphere. We performed a standard 1D LTE analysis to compute the abundances. Considering all the stars as representative of the same population of low mass galaxies, we found that the [alpha/Fe] ratios vs [Fe/H] decreases as the metallicity of the star increases in a way similar to what is found for the population of stars belonging to dwarf spheroidal galaxies. The main difference is that the solar [alpha/Fe] is reached at a much lower metallicity for the UfDSph than the dwarf spheroidal galaxies. We report for the first time the abundance of strontium in CVnI. The star we analyzed in this galaxy has a very high [Sr/Fe] and a very low upper limit of barium which makes it a star with an exceptionally high [Sr/Ba] ratio. Our results seem to indicate that the galaxies which have produced the bulk of their stars before the reionization (fossil galaxies) have lower [X/Fe] ratios at a given metallicity than the galaxies that have experienced a discontinuity in their star formation rate (quenching).Comment: 22 pages, 12 figures, submitted to A&

Detailed abundances in stars belonging to ultra-faint dwarf spheroidal galaxies

We report preliminary results concerning the detailed chemical composition of metal poor stars belonging to close ultra-faint dwarf galaxies (hereafter UfDSphs). The abundances have been determined thanks to spectra obtained with X-Shooter, a high efficiency spectrograph installed on one of the ESO VLT units. The sample of ultra-faint dwarf spheroidal stars have abundance ratios slightly lower to what is measured in field halo star of the same metallicity.We did not find extreme abundances in our Hercules stars as the one found by Koch for his 2 Hercules stars. The synthesis of the neutron capture elements Ba and Sr seems to originate from the same nucleosynthetic process in operation during the early stages of the galactic evolution.Comment: 3 pages, 1 figure; OMEG11 conference (Tokyo, Nov 2011

Non-descent vaginal hysterectomy in previous cesarean section: a retrospective study of 30 cases

Background: Non-Descent Vaginal Hysterectomy (NDVH) is removal of uterus through vagina in non-prolapsed uterus. Objective of present study was to assess safety, feasibility of NDVH in patients with previous cesarean section.Methods: Retrospective study was conducted in department of Obstetrics and Gynecology of Shree Dharmasthala Manjunatheshwara (SDM) College of Medical Sciences, Dharwad, India from April 2008 to June 2016. Effort was made to perform hysterectomies vaginally in women with benign conditions with history of one, two or three caesarean sections. Information regarding age, parity, number of previous LSCS, uterine size, blood loss, duration of operation, difficulties in separating bladder, intra -operative, post-operative complications were recorded.Results: Total thirty cases were selected for NDVH with history of one, two and three cesarean sections. All successfully underwent NDVH, except one in which bladder injury occurred which was repaired at same time vaginally. Thirteen patients had previous one Lower Segment Cesarean Section (LSCS), sixteen had two LSCS and one had three LSCS. Commonest indication was abnormal uterine bleeding followed by leiomyoma of uterus. Mean duration of surgery was 97 min. Mean blood loss was 150 ml. Post-operative complications were minimal. Patient mobility, resumption of daily activities was fast. Mean hospital stay was 4-5 days.Conclusions: Vaginal hysterectomy is safe, cost effective method of hysterectomy in women with previous cesarean section scar requiring hysterectomy for benign conditions with fewer complications, shorter hospital stay and less morbidity

Young stars in the periphery of the Large Magellanic Cloud

Despite their close proximity, the complex interplay between the two Magellanic Clouds, the Milky Way, and the resulting tidal features, is still poorly understood. Recent studies have shown that the Large Magellanic Cloud (LMC) has a very extended disk strikingly perturbed in its outskirts. We search for recent star formation in the far outskirts of the LMC, out to ~30 degrees from its center. We have collected intermediate-resolution spectra of thirty-one young star candidates in the periphery of the LMC and measured their radial velocity, stellar parameters, distance and age. Our measurements confirm membership to the LMC of six targets, for which the radial velocity and distance values match well those of the Cloud. These objects are all young (10-50 Myr), main-sequence stars projected between 7 and 13 degrees from the center of the parent galaxy. We compare the velocities of our stars with those of a disk model, and find that our stars have low to moderate velocity differences with the disk model predictions, indicating that they were formed in situ. Our study demonstrates that recent star formation occurred in the far periphery of the LMC, where thus far only old objects were known. The spatial configuration of these newly-formed stars appears ring-like with a radius of 12 kpc, and a displacement of 2.6 kpc from the LMC's center. This structure, if real, would be suggestive of a star-formation episode triggered by an off-center collision between the Small Magellanic Cloud and the LMC's disk.Comment: Accepted for publication in MNRA

Anchors for the Cosmic Distance Scale: the Cepheids U Sgr, CF Cas and CEab Cas

New and existing X-ray, UBVJHKsW(1-4), and spectroscopic observations were analyzed to constrain fundamental parameters for M25, NGC 7790, and dust along their sight-lines. The star clusters are of particular importance given they host the classical Cepheids U Sgr, CF Cas, and the visual binary Cepheids CEa and CEb Cas. Precise results from the multiband analysis, in tandem with a comprehensive determination of the Cepheids' period evolution (dP/dt) from ~140 years of observations, helped resolve concerns raised regarding the clusters and their key Cepheid constituents. Specifically, distances derived for members of M25 and NGC 7790 are 630+-25 pc and 3.40+-0.15 kpc, respectively.Comment: To appear in Astronomy and Astrophysic

Ultra-deep GEMINI near-infrared observations of the bulge globular cluster NGC 6624

We used ultra-deep $J$ and $K_s$ images secured with the near-infrared GSAOI camera assisted by the multi-conjugate adaptive optics system GeMS at the GEMINI South Telescope in Chile, to obtain a ($K_s$, $J-K_s$) color-magnitude diagram (CMD) for the bulge globular cluster NGC 6624. We obtained the deepest and most accurate near-infrared CMD from the ground for this cluster, by reaching $K_s$ $\sim$ 21.5, approximately 8 magnitudes below the horizontal branch level. The entire extension of the Main Sequence (MS) is nicely sampled and at $K_s$ $\sim$ 20 we detected the so-called MS "knee" in a purely near-infrared CMD. By taking advantage of the exquisite quality of the data, we estimated the absolute age of NGC 6624 ($t_{age}$ = 12.0 $\pm$ 0.5 Gyr), which turns out to be in good agreement with previous studies in the literature. We also analyzed the luminosity and mass functions of MS stars down to M $\sim$ 0.45 M$_{\odot}$ finding evidence of a significant increase of low-mass stars at increasing distances from the cluster center. This is a clear signature of mass segregation, confirming that NGC 6624 is in an advanced stage of dynamical evolution.Comment: Accepted for publication by ApJ. 39 pages, 19 figures, 1 tabl

ACCOUNTING STANDARDS IN CHURCH FINANCIAL MANAGEMENT: “BRINGING FINANCIAL PRACTICE AND THEOLOGY MORE INTIMATELY INTERTWINED”

Purpose: This paper aims to assess accounting application in church financial reporting. Methodology: There were two main stages of this research methodology. Firstly, an extensive literature study was to develop the framework of the relationship between religion and accounting and to find the research gap to be fulfilled in theoretical based. Secondly, the technical research method included a case study approach to examine the current application of the church financial report and the PSAK 45 accounting application. Results: There are significant discrepancies between the Treasury Report made by the church and the financial statements made under PSAK 45. The information under PSAK 45 provides more relevant information to the stakeholders to assess how the church actualizes the theology values into its activities. Firstly, the PSAK 45 Activity Report reveals the information for the stakeholders, particularly the management, to evaluate the effect of money proportioned into church activity. Secondly, the reports show how the direct and indirect costs are allocated into services activities to assess, how much direct cost has been allocated to successfully implement the mission through the roles. Thirdly, the reports tell stakeholders how the church manages its activities effectively to serve not only the congregations but also the wider society in order to attain its vision. Finally, the balance sheet reveals the increasing or decreasing value of net assets and how the assets are effectively used – or not. Implications: The benefits of the implementation of the accounting standard to help the church to implement their sacred mission and criticizes the opponent's views that perceive accounting as profane, and irrelevant as well as irreverent. It provides significance that accounting standards should be mandatory in Indonesia for all non-profit groups