Zobrazeno 1 - 10
of 51
pro vyhledávání: '"Bacham E. Reddy"'
Publikováno v:
The Astrophysical Journal Letters, Vol 971, Iss 1, p L3 (2024)
This Letter presents results from Kepler photometric light curves and a high-resolution spectroscopic study of a super-Li-rich giant KIC11087027. Using the light-curve analysis, we measured the star’s rotational period P _rot = 30.4 ± 0.1 days, wh
Externí odkaz:
https://doaj.org/article/fe33aac9429741e7865022c8ebefb1ee
Publikováno v:
The Astrophysical Journal, Vol 966, Iss 1, p 109 (2024)
The presence of a large amount of Li in giants is still a mystery. Most of the super Li-rich (SLR) giants reported in recent studies are in the solar metallicity regime. Here, we study the five metal-poor SLRs from the Galactic Archeology with HERMES
Externí odkaz:
https://doaj.org/article/b7fd012f1a914df7a7b4cbce4de54635
Publikováno v:
The Astrophysical Journal Letters, Vol 944, Iss 1, p L5 (2023)
In this work, we studied the distribution of lithium abundances in giants as a function of stellar mass. We used a sample of 1240 giants common among Kepler photometric and LAMOST medium-resolution ( R ≈ 7500) spectroscopic survey fields. The aster
Externí odkaz:
https://doaj.org/article/bc69997b7b3848eeb4a0ac1df3741327
Publikováno v:
The Astrophysical Journal, Vol 957, Iss 1, p 18 (2023)
Carbon-deficient red giants (CDGs) are a peculiar class of stars that have eluded explanation for decades. We aim to better characterize CDGs by using asteroseismology (Kepler, TESS) combined with spectroscopy (APOGEE, LAMOST), and astrometry (Gaia).
Externí odkaz:
https://doaj.org/article/0f5947dd290649ecacd14f4cfc616d7a
Publikováno v:
Monthly Notices of the Royal Astronomical Society. 511:3741-3750
We have performed a search among low mass red giants for finding evidence for merger scenario for triggering He-flash and subsequent Li enhancement. We chose a sample of red giants from GALAH survey with well-measured Li abundances, and near and mid-
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::b4a8b4a6ae11f94dde9816224ef05ce4
https://doi.org/10.1093/mnras/stac224
https://doi.org/10.1093/mnras/stac224
In this work, we studied the distribution of lithium abundances in giants as a function of stellar mass. We used a sample of 1240 giants common among Kepler photometric and LAMOST medium resolution (R $\approx$ 7500) spectroscopic survey fields. The
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::ab0dd7e6f518d3cb22aab4b18bd04f12
http://arxiv.org/abs/2301.10436
http://arxiv.org/abs/2301.10436
Autor:
Christopher Sneden, Melike Afşar, Zeynep Bozkurt, Monika Adamów, Anohita Mallick, Bacham E. Reddy, Steven Janowiecki, Suvrath Mahadevan, Brendan P. Bowler, Keith Hawkins, Karin Lind, Andrea K. Dupree, Joe P. Ninan, Neel Nagarajan, Gamze Böcek Topcu, Cynthia S. Froning, Chad F. Bender, Ryan Terrien, Lawrence W. Ramsey, Gregory N. Mace
We have gathered near-infrared zyJ-band high-resolution spectra of nearly 300 field red giant stars with known lithium abundances in order to survey their He i lambda 10830 absorption strengths. This transition is an indicator of chromospheric activi
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::ca1ded79d3d78e92626cc017d76f0f06
We report novel observational evidence on the evolutionary status of lithium-rich giant stars by combining asteroseismic and lithium abundance data. Comparing observations and models of the asteroseismic gravity-mode period spacing $����_{1}$
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::2512ff223b7992f6ac6f6ae1d3912255
http://arxiv.org/abs/2104.12070
http://arxiv.org/abs/2104.12070
Autor:
Bacham E. Reddy, Yerra Bharat Kumar
Publikováno v:
Journal of Astrophysics and Astronomy. 41
The overabundance of lithium in low-mass red giants has been a topic of interest for over four decades. Low-mass stars are expected to destroy lithium gradually throughout their lifetimes. Against this expectation, about $$1\%$$ of red giants in the
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::0796d08ebae1aa97d29bf0f4000bd866
https://doi.org/10.1007/s12036-020-09660-9
https://doi.org/10.1007/s12036-020-09660-9
Publikováno v:
Monthly Notices of the Royal Astronomical Society.
Compositions of lithium-enriched and normal giants among the GALAH survey are compared. Except for Li, the only detectable abundance difference between lithium-enriched and normal giants among the investigated elements from carbon to europium occurs
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::f08c8ab712dc95d6a20978254b33f617
https://doi.org/10.1093/mnras/staa729
https://doi.org/10.1093/mnras/staa729