scholarly journals Chemical history of isolated dwarf galaxies of the Local Group – I. dSphs: Cetus and Tucana

2016 ◽  
Vol 457 (4) ◽  
pp. 4012-4020 ◽  
Author(s):  
N. Avila-Vergara ◽  
L. Carigi ◽  
S. L. Hidalgo ◽  
R. Durazo
Keyword(s):  
Local Group ◽  
Dwarf Galaxies ◽  
Group I ◽  
History Of ◽  
Chemical History

scholarly journals Constraints on Interactions and Mergers from dSph Galaxies and Globular Clusters

1999 ◽  
Vol 186 ◽  
pp. 52-52
Author(s):  
E.K. Grebel
Keyword(s):  
Globular Clusters ◽  
Milky Way ◽  
Local Group ◽  
Galactic Halo ◽  
Dwarf Galaxies ◽  
Thick Disk ◽  
History Of

Observations at high redshifts are revealing numerous interactions and ongoing mergers. Our own Milky Way is currently merging with the Sagittarius dwarf spheroidal (dSph) galaxy. Past mergers with dwarf galaxies may have contributed significantly to the Galactic halo and possibly to the thick disk. The properties of Local Group dSphs and halo globular clusters impose constraints on the merger history of the Milky Way.

scholarly journals The distinct stellar metallicity populations of simulated Local Group dwarfs

2019 ◽  
Vol 488 (2) ◽  
pp. 2312-2331 ◽  
Author(s):  
Anna Genina ◽  
Carlos S Frenk ◽  
Alejandro Benítez-Llambay ◽  
Shaun Cole ◽  
Julio F Navarro ◽  
...  
Keyword(s):  
Star Formation ◽  
Local Group ◽  
Dwarf Galaxies ◽  
Mass Range ◽  
Spatial Segregation ◽  
Ram Pressure ◽  
History Of ◽  
Hydrodynamical Simulations ◽  
Two Populations ◽  
Poor Population

ABSTRACT A number of Local Group dwarf galaxies are known to have two spatially segregated stellar metallicity populations, a centrally concentrated metal-rich population, and a more extended metal-poor population. In this work we discuss mechanisms that lead to the formation of two spatially segregated metallicity populations. Using a set of high-resolution hydrodynamical simulations of Local Group-like environments, we select a sample of satellite and field galaxies, spanning the stellar mass range 106–109 M⊙, that exhibit bimodality in their metallicity distributions. Among those, we identify a subsample with a strong spatial segregation in the two populations. We find three distinct mechanisms for their formation. In field dwarfs and in a small fraction of satellites, a merger causes the metal-poor stars to migrate to larger radii and encourages the available gas to sink to the centre of the dwarf. Most of the gas is subsequently blown out of the halo through star formation feedback, but the remaining gas is consumed in the formation of a metal-rich population. In the exclusive case of satellites that have retained some of their gas at infall, it is the compression of this gas by ram pressure near pericentre that triggers the formation of metal-rich stars, whilst simultaneously preventing star formation at larger radii through stripping. Additionally, in a small number of field and satellite dwarfs, interactions with gaseous filaments and other galaxies can result in the formation of a metal-rich population. Regardless of the formation mechanism, a history of mergers typically enhances the spatial segregation.

scholarly journals The Faint Globular Cluster in the Dwarf Galaxy Andromeda I

2017 ◽  
Vol 34 ◽  
Author(s):  
Nelson Caldwell ◽  
Jay Strader ◽  
David J. Sand ◽  
Beth Willman ◽  
Anil C. Seth
Keyword(s):  
Dark Matter ◽  
Globular Cluster ◽  
Globular Clusters ◽  
Local Group ◽  
Dwarf Galaxies ◽  
Dwarf Galaxy ◽  
Dark Matter Halos ◽  
History Of ◽  
Low Mass ◽  
Growing Population

AbstractObservations of globular clusters in dwarf galaxies can be used to study a variety of topics, including the structure of dark matter halos and the history of vigorous star formation in low-mass galaxies. We report on the properties of the faint globular cluster (MV ~ −3.4) in the M31 dwarf galaxy Andromeda I. This object adds to the growing population of low-luminosity Local Group galaxies that host single globular clusters.

scholarly journals Pulsating Variable Stars in Local Group Dwarf Galaxies

2000 ◽  
Vol 176 ◽  
pp. 187-192
Author(s):  
Mario Mateo
Keyword(s):  
Local Group ◽  
Dwarf Galaxies ◽  
Current Knowledge ◽  
Physical Nature ◽  
Variable Stars ◽  
Group I ◽  
Pulsating Variable Stars ◽  
Nearby Galaxies ◽  
Observational Techniques ◽  
Distance Indicators

AbstractPulsating variables stars have had a long and prominent history in helping to map out the local Universe. Current observational techniques now make it possible to identify examples of all non-degenerate radial pulsating variables throughout much of the Local Group. I review our current knowledge of such variables in the dwarf galaxies of the Local Group. This summary tries to highlight some recent results that help underscore the use of these stars as important tools to study the physical nature of their parent galaxies as well as their continued use as important distance indicators of nearby galaxies.

ROLE OF LIPID PROFILE IN OVARIAN CARCINOMA PATIENTS

2019 ◽  
Vol 3 (8) ◽  
Author(s):  
Dr. Manisha ◽  
Dr. Ruchi Jindal
Keyword(s):  
Ovarian Cancer ◽  
Lipid Profile ◽  
Cancer Patients ◽  
Ovarian Tumor ◽  
Ovarian Cancer Risk ◽  
Low Level ◽  
Medical College ◽  
Group I ◽  
History Of

Background: The term "ovarian cancer" includes several different types of cancer that  arise from cells of the ovary, most commonly, tumors arise from the epithelium or lining cells of the ovary.  Ovarian cancer risk is positively associated with higher consumption of dietary cholesterol and eggs, and inversely associated with a higher intake of vegetables. High consumption of fats may increase circulating estrogen levels, thus increasing the possibility of cell damage and proliferation that is responsible for cancerous growth. Material & Methods: The present study was conducted at Geetanjali Medical College and Hospital, Udaipur (Rajasthan). Total  100 cases (females) attending the obstetrics and gynecology department for some gynecological and other problem  were selected for this study between the age of 40-60 years, who were attending cancer centre at GEETANJALI MEDICAL COLLEGE AND  HOSPITAL, Udaipur (Rajasthan).                GROUP I: - It consisted of healthy females control subjects (n=50) .By routine examination and tests, we ensured that all the subjects were healthy and there were no signs and symptoms or history of ovarian tumor and diseases GROUP II: - It consisted of ovarian cancer females subjects (n=50) with a history of ovarian tumor. Results:   Higher level of cholesterol, LDL, VLDL and low level of HDL are found in ovarian cancer patients. Conclusion: The present study we highlights the importance and role of serum lipid profile in diagnosis, prognosis and recurrence of the disease. The study shows that serum level of cholesterol, LDL, VLDL was elevated in  patients of ovarian cancer while low level of HDL are found in ovarian cancer patients. Key words: lipid profile, ovarian cancer.

The Star Formation History of the Local Group Dwarf Galaxy Leo I

1999 ◽  
Vol 118 (5) ◽  
pp. 2245-2261 ◽  
Author(s):  
Carme Gallart ◽  
Wendy L. Freedman ◽  
Antonio Aparicio ◽  
Giampaolo Bertelli ◽  
Cesare Chiosi
Keyword(s):  
Star Formation ◽  
Local Group ◽  
Dwarf Galaxy ◽  
Star Formation History ◽  
Formation History ◽  
History Of

Subaru Hyper Suprime-Cam Survey for the Local Group Dwarf Galaxies: Ursa Minor

2018 ◽  
Vol 14 (S344) ◽  
pp. 94-95
Author(s):  
Yutaka Komiyama
Keyword(s):  
Binary Systems ◽  
Main Sequence ◽  
Local Group ◽  
Dwarf Galaxies ◽  
Structural Parameters ◽  
Deep Imaging ◽  
Ursa Minor ◽  
Red Giant

AbstractWe have carried out a wide and deep imaging survey for the Local Group dwarf spheroidal galaxy Ursa Minor (UMi) using Hyper Suprime-Cam (HSC). The data cover out beyond the nominal tidal radius down to ~25 mag in i band, which is ~2 mag below the main sequence turn-off point. The structural parameters of UMi are derived using red giant branch (RGB) stars and sub-giant branch (SGB) stars, and the tidal radius is suggested to be larger than those estimated by the previous studies. It is also found that the distribution of bluer RGB/SGB stars is more extended than that of redder RGB/SGB stars. The fraction of binary systems is estimated to be ~0.4 from the morphology of the main sequences.

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