Results 21 to 30 of about 12,062 (300)

Beyond Spectroscopy. II. Stellar Parameters for over 20 Million Stars in the Northern Sky from SAGES DR1 and Gaia DR3

The Astrophysical Journal, 2023
We present precise photometric estimates of stellar parameters, including effective temperature, metallicity, luminosity classification, distance, and stellar age, for nearly 26 million stars using the methodology developed in the first paper of this ...
Yang Huang, Timothy C. Beers, Haibo Yuan, Ke-Feng Tan, Wei Wang, Jie Zheng, Chun Li, Young Sun Lee, Hai-Ning Li, Jing-Kun Zhao, Xiang-Xiang Xue, Yujuan Liu, Huawei Zhang, Xue-Ang Sun, Ji Li, Hong-Rui Gu, Christian Wolf, Christopher A. Onken, Jifeng Liu, Zhou Fan, Gang Zhao   +20 more
doaj   +1 more source

Research on the Detection Method of Projection Stellar Target Simulator

Photonics, 2023
The projection stellar target simulator is a stellar target simulator in which star points are projected to be imaged on a fixed plane at a fixed distance.
Jianan Kang, Ru Zheng, Lingyun Wang, Chengwei Pang, Guangxi Li   +4 more
doaj   +1 more source

The Absolute Age of M92

The Astronomical Journal, 2023
The absolute age of a simple stellar population is of fundamental interest for a wide range of applications but is difficult to measure in practice, as it requires an understanding of the uncertainties in a variety of stellar evolution processes as well ...
Jiaqi (Martin) Ying, Brian Chaboyer, Emily M. Boudreaux, Catherine Slaughter, Michael Boylan-Kolchin, Daniel Weisz   +5 more
doaj   +1 more source

Estimating Distances from Parallaxes. VI. A Method for Inferring Distances and Transverse Velocities from Parallaxes and Proper Motions Demonstrated on Gaia Data Release 3

The Astronomical Journal, 2023
The accuracy of stellar distances inferred purely from parallaxes degrades rapidly with distance. Proper motion measurements, when combined with some idea of typical velocities, provide independent information on stellar distances.
C. A. L. Bailer-Jones
doaj   +1 more source

Comparative Analysis of TRGBs (CATs) from Unsupervised, Multi-halo-field Measurements: Contrast is Key

The Astrophysical Journal, 2023
The tip of the red giant branch (TRGB) is an apparent discontinuity of the luminosity function (LF) due to the end of the red giant evolutionary phase and is used to measure distances in the local universe.
J. Wu, D. Scolnic, A. G. Riess, G. S. Anand, R. Beaton, S. Casertano, X. Ke, S. Li   +7 more
doaj   +1 more source

A Catalog of Distance Determinations for the LAMOST DR8 K Giants in the Galactic Halo

The Astronomical Journal, 2023
We present a catalog of distances for 19,544 K giants drawn from Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) DR8. Most of them are located in the halo of the Milky Way up to ∼120 kpc.
Lan Zhang, Xiang-Xiang Xue, Chengqun Yang, Feilu Wang, Hans-Walter Rix, Gang Zhao, Chao Liu   +6 more
doaj   +1 more source

On the correlations between galaxy properties and supermassive black hole mass [PDF]

, 2011
We use a large sample of upper limits and accurate estimates of supermassive black hole (SMBH) masses coupled with libraries of host galaxy velocity dispersions, rotational velocities and photometric parameters extracted from Sloan Digital Sky Survey i ...
Beifiori, A., A. Beifiori, BEIFIORI A., Corsini, E., Courteau, S., CORSINI, ENRICO MARIA, Y. Zhu, E. M. Corsini, Zhu, Y., COURTEAU S., ZHU Y., S. Courteau   +11 more
core   +1 more source

Light-curve Recovery with the Vera Rubin Observatory’s LSST. I. Pulsating Stars in Local Group Dwarf Galaxies

The Astrophysical Journal Supplement Series, 2023
This investigation is mainly focused on the LSST Survey Strategy Optimization process, a bottom-up approach that turned out to be quite effective in involving the scientific community in the definition of the LSST observing strategy.
M. Di Criscienzo, S. Leccia, V. Braga, I. Musella, G. Bono, M. Dall’Ora, G. Fiorentino, M. Marconi, R. Molinaro, V. Ripepi, K. Carrell, Y. Choi, S. Savarese, L. Schreiber   +13 more
doaj   +1 more source

Early assembly of the most massive galaxies [PDF]

, 2009
The current consensus is that galaxies begin as small density fluctuations in the early Universe and grow by in situ star formation and hierarchical merging(1).
Chris A. Collins, Scott T Kay (16045382), Nicola Mehrtens (16047884), Ed Lloyd-Davies, Hoyle, Ben, Hosmer, Mark, Christopher J. Miller, Ben Hoyle, Mehrtens, Nicola, Robert G. Mann, Pedro T. P. Viana, Martin Sahlén (267044), S Adam Stanford (16061237), Mark Hosmer (16070585), Robert C Nichol (16067396), John P Stott (16070582), Martin Sahlén, Sahlen, Martin, John P. Stott, Kathy Romer (4460893), Matt Hilton (6956609), Viana, Pedro T. P., Mann, Robert G., Ben Hoyle (6914513), Stott, John P., Matt Hilton, Robert G Mann (7965452), Andrew Liddle, Stanford, S. Adam, Christopher J Miller (16070591), A. Kathy Romer, Davidson, Michael, Ed Lloyd-Davies (16075100), Romer, A. Kathy, Robert C. Nichol, Andrew Liddle (16042793), Pedro T P Viana (16045379), Nichol, Robert C., Kay, Scott T., Michael J. West, Chris A Collins (16061234), Scott T. Kay, Collins, Chris A., Michael Davidson, Mark Hosmer, West, Michael J., Michael Davidson (699678), S. Adam Stanford, Michael J West (5524436), Liddle, Andrew, Nicola Mehrtens, Miller, Christopher J., Hilton, Matt, Lloyd-Davies, Ed   +53 more
core   +1 more source

Modeling of Magnetospheres of Terrestrial Exoplanets in the Habitable Zone around G-Type Stars

Universe, 2022
Using a paraboloid model of an Earth-like exoplanetary magnetospheric magnetic field, developed from a model of the Earth, we investigate the magnetospheric structure of planets located in the habitable zone around G-type stars.
Elena S. Belenkaya, Igor I. Alexeev, Marina S. Blokhina   +2 more
doaj   +1 more source