Horizontal Branch stars | COSMOS
Horizontal Branch stars. This is a phase of stellar evolution undergone by intermediate- mass stars, i.e. those with masses 0.8 M⊙ < < 8 M⊙, a range which encompasses the majority of stars in the Galaxy, including our Sun. After departing the Main Sequence, these stars spend time on the Red Giant Branch, a phase characterised by hydrogen ...
Horizontal gene transfer in evolution: facts and challenges
2. How important is horizontal gene transfer in evolution of earth's biota? Since the emergence of horizontal gene transfer as a way of explaining phylogenetic incongruence using different gene trees, a considerable number of studies have been published about genes that have been acquired by horizontal gene transfer (Gogarten …
The ages of stars: The horizontal branch
The ages of stars: The horizontal branch M. Catelan†‡ Pontificia Universidad ´olica de Chile, Departamento de Astronom´ıa y Astrof´ısica, Av. Vicu˜na Mackenna 4860, 782-0436 Macul, Santiago, Chile email: [email protected] Abstract.Horizontal branch (HB) stars play a particularly important role in the "age debate,"
Blue Horizontal Branch Stars in Four Globular Clusters
Several globular clusters with the same values of the primary parameters (age and chemical composition) show different horizontal branch (HB) morphologies, which may also be characterized by gaps or bimodal stellar distributions. Several parameters have been...
Hot HB stars in globular clusters: physical …
Hot HB stars in globular clusters: physical parameters and consequences for theory. I. M 15 and its blue faint horizontal branch with gap. Moehler, S. ; Heber, U. ; de Boer, K. S. …
On the Horizontal Branch morphology: a new …
Aims. To investigate the variation of the horizontal branch morphology in Galactic globular clusters, we define a new photometric horizontal branch morphology index, overcoming …
Lecture 16: Low-Mass Stellar Evolution
Horizontal Branch Phase Structure: He-burning core H-burning shell The Triple-alpha Process is very inefficient at producing energy, so it can only last for about 100 Myr. ... Consequences: Small changes in T lead to Large changes in fusion energy output Star experiences huge Thermal Pulses that destabilize the outer envelope.
[1212.4419] The Horizontal Branch in the UV Colour Magnitude Diagrams
These systems represents a classical example of clusters in the intermediate metallicity regime that, even sharing similar metal content and age, show remarkably different Horizontal Branch morphologies. As a consequence, the observed differences in the colour distributions of Horizontal Branch stars cannot be interpreted in terms of …
The environmental and economic consequences of …
1. Introduction. Decentralized governance is anticipated to transfer authority, resources, and responsibility from central to sub-national governments, encouraging local economic growth and public welfare provision while enhancing democracy (Faguet, 2014).In the case of China, a country in transition, the decentralization in the economic and …
Horizontal Branch | USA Plumbing
Horizontal Branch. A horizontal branch is a lateral drain pipe which runs from the plumbing fixtures to the waste stack in a building or into the soil. 1222 reads.
Horizontal-Branch Stars | Request PDF
High-resolution spectroscopic measurements of blue horizontal-branch stars in six metal-poor globular clusters -- M3, M13, M15, M68, M92, and NGC 288 -- reveal remarkable variations in ...
Abundance Anomalies in Horizontal Branch Stars and
Extreme horizontal branch stars, which can have surface gravities comparable to the lowest gravity WDs, have longer ∼10 6 yr diffusion timescales (Michaud et al. 2008). These diffusion ...
Identification of Blue Horizontal Branch Stars with …
Blue horizontal branch stars (BHBs) are metal-poor (Santucci et al. 2015) A or B-type stars that burn helium in their cores (Barbosa et al. 2022).The inadequate understanding of the Galactic haloes' aggregate masses, dimensions, and formation history is primarily due to the inadequacy of extensive dynamic tracer sets at sufficiently …
HORIZONTAL GENE TRANSFER: Evidence and Possible Consequences
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Horizontal Branch Stellar Evolution
Ben Dorman1,2. 1Laboratory for Astronomy & Solar Physics, NASA/GSFC, Greenbelt, Maryland 20771, USA 2NAS/NRC Resident Research Associate. Abstract: I review aspects of the evolution of horizontal branch (HB) stars. The defining characteristic of this, the core He-burning phase of evolution for M < Mflash ∼ 2.2 M⊙, is a spread in observed ...
The Final Stages of the Evolution of a Sun-like Star
This has important consequences in stellar evolution, so I will briefly describe what this means. The gas inside stars is a soup of atomic nuclei and free electrons. If you compress a gas of this type to a high enough density, you have to use two of the laws of quantum mechanics to describe its behavior. ... Horizontal branch: 10 8 years ~4500 ...
HORIZONTAL GENE TRANSFER: Evidence and Possible …
entered the chicken by a horizontal transfer, possibly by a viral mediated retrotransposition (because it is an intronless gene). The case for a migratory chicken calmodulin was inferred from the minimal replacement tree based on the half dozen available sequences. Today, there are over 60 different sequences (66).
Helium variation due to self–pollution among Globular …
Consequences on the horizontal branch morphology. F. D'Antona 1, V. Caloi 2, ... However, the difference in the evolving mass may play a role in the morphology of the horizontal branch, and in particular in the formation of blue tails, in those globular clusters which show strong CNO abundance variations, such as M13 and NGC 6752. ...
Lecture 40: The Once and Future Sun
The Sun descends quickly onto the Horizontal Branch in about 1 Myr as it rearranges its internal structure to accomodate this new source of energy. The Horizontal Branch With a new source of energy (He fusion), the Sun settles onto the Horizontal Branch for a brief "retirement" period of Hydrostatic and Thermal Equilibrium:
Zero-age horizontal branch structures: pseudo versus fully …
L. Piersanti, A. Tornambé, V. Castellani, Zero-age horizontal branch structures: pseudo versus fully evolutionary models, Monthly Notices of the Royal Astronomical Society, Volume 353, Issue 1, ... but with an increased abundance of carbon in the He core by about 5 per cent by mass as a consequence of the He-burning flashes. …
Can Planets Influence the Horizontal Branch …
The planets deposit angular momentum and energy into the red giant stars' envelopes, both of which are likely to enhance mass loss on the red giant branch. The enhanced mass loss causes the star to become bluer as it turns to the horizontal branch.
Gaps in the blue horizontal branch (Journal Article)
@article{osti_7194974, title = {Gaps in the blue horizontal branch}, author = {Newell, B and Graham, J A}, abstractNote = {Data leads to the conclusion that several distinct groups of stars exist on the field stars horizontal branch sequence. Consideration of current understanding of the advanced evolution of Population II stars indicates that, if …
Horizontal Standpipes and Lateral Piping | SpringerLink
Abstract. There are a couple of reasons that horizontal piping will be used in a standpipe other than the feed mains that interconnect vertical standpipes. The first type of horizontal pipe is a branch line that connects a single hose connection to a standpipe. The second type of horizontal pipe is a horizontal standpipe, which is defined as ...
The Fate of the Sun
The horizontal branch of the giants. In a time between 1 and 10 million years, the transition from the red-giant branch to the horizontal branch of the giants ends. As for the internal structure ...
Horizontal branch
The horizontal branch (HB) is a stage of stellar evolution that immediately follows the red giant branch in stars whose masses are similar to the Sun's. Horizontal-branch stars are powered by helium fusion in the core (via the triple-alpha process) and by hydrogen fusion (via the CNO cycle) in a shell surrounding the core. ...
The Horizontal Branch
The Horizontal Branch. Evolution on the horizontal branch (HB) is similar to main sequence evolution since it is a period of stable core burning (but of helium, rather than hydrogen). For this reason, it is sometimes called the "helium main sequence". However, the time of stable helium core burning is much shorter than the time of stable ...
Mechanisms and consequences of horizontal gene transfer …
Syvanen, M. (1994) Horizontal gene transfer: Evidence and possible consequences. Annu. Rev. Genet 28: 237–261. Article PubMed CAS Google Scholar Thoms, B. and Wackernagel, W. (1984) Genetic control of damage-inducible restriction alleviation in Escherichia coli K12: An SOS function not repressed by lexA.
[astro-ph/0209331] Helium variation due to self-pollution …
Download a PDF of the paper titled Helium variation due to self-pollution among Globular Cluster stars: consequences on the horizontal branch morphology, by F. D'Antona (1) and 11 other authors. Download PDF
Can Planets Influence the Horizontal Branch Morphology?
This dependence may explain some of the anomalies and variations in the horizontal branch morphologies between different globular clusters. The proposed scenario predicts that surviving massive planets or brown dwarfs orbit some of the extreme blue horizontal branch stars, at orbital periods of ∼10 days. Export citation and abstract …
Exam 3 Flashcards | Quizlet
Low mass stars move _____ and to the _____ on the HR diagram as they climb the Red Giant Branch. up; right. A Type Ia supernova occurs when a white dwarf reaches a mass of _____. ... Which point on the figure below represents the location on the H-R diagram where the star is on the "horizontal branch"? (Note: this appears without the "highlight ...
