Zobrazeno 1 - 10
of 126
pro vyhledávání: '"Lian, Jianhui"'
Both simulations and observations suggest that the disk assembly of galaxies is governed by the interplay between coplanar gas inflow, ex-planar gas outflow and in-situ star formation on the disk, known as the leaky accretion disk. This scenario pred
Externí odkaz:
http://arxiv.org/abs/2406.11394
Autor:
Lian, Jianhui, Zasowski, Gail, Chen, Bingqiu, Imig, Julie, Wang, Tao, Boardman, Nicholas, Liu, Xiaowei
The size of a galaxy is one of the fundamental parameters that reflects its growth and assembly history. Traditionally, the size of the Milky Way has been characterized by the scale length of the disk, based on the assumption of an exponential densit
Externí odkaz:
http://arxiv.org/abs/2406.05604
Autor:
Rix, Hans-Walter, Chandra, Vedant, Zasowski, Gail, Pillepich, Annalisa, Khoperskov, Sergey, Feltzing, Sofia, Wyse, Rosemary F., Frankel, Neige, Horta, Danny, Kollmeier, Juna, Stassun, Keivan G., Ness, Melissa, Bird, Jonathan C., Nidever, David L., Fernandez, Jose G., Amarante, João A., Laporte, Chervin F., Lian, Jianhui
We show with Gaia XP spectroscopy that extremely metal-rich stars in the Milky Way (EMR; $[M/H]_{XP} > 0.5$) - but only those - are largely confined to a tight "knot" at the center of the Galaxy. This EMR knot is round in projection, has a fairly abr
Externí odkaz:
http://arxiv.org/abs/2406.01706
Autor:
Chen, Xinlei, Kumar, Brajesh, Er, Xinzhong, Guo, Helong, Yang, Yuan-Pei, Lin, Weikang, Fang, Yuan, Du, Guowang, Liu, Chenxu, Zhao, Jiewei, Zhang, Tianyu, Bao, Yuxi, Zou, Xingzhu, Pan, Yu, Wang, Yu, Zhu, Xufeng, Chatterjee, Kaushik, Liu, Xiangkun, Liu, Dezi, Lagioia, Edoardo P., Rangwal, Geeta, Zhong, Shiyan, Zhang, Jinghua, Lian, Jianhui, Cai, Yongzhi, Zhang, Yangwei, Liu, Xiaowei
We present early-phase good cadence simultaneous multi-band ($ugi$, $vrz$--bands) imaging of nearby supernova SN 2024ggi, which exploded in the nearby galaxy, NGC~3621. A quick follow-up was conducted within less than a day after the explosion and co
Externí odkaz:
http://arxiv.org/abs/2405.07964
Autor:
Lian, Jianhui, Luo, Li
Although thick disk is a structure prevalent in local disk galaxies and also present in our home Galaxy, its formation and evolution is still unclear. Whether the thick disk is born thick and/or gradually heated to be thick after formation is under d
Externí odkaz:
http://arxiv.org/abs/2312.07070
In the epoch of deep photometric surveys, a large number of substructures, e.g., over-densities, streams, were identified. With the help of astrometry and spectroscopy, the community revealed a complex picture of our Milky Way (MW) after investigatin
Externí odkaz:
http://arxiv.org/abs/2311.15519
Autor:
Lian, Jianhui, Storm, Nicholas, Guiglion, Guillaume, Serenelli, Aldo, Cote, Benoit, Karakas, Amanda I., Boardman, Nick, Bergemann, Maria
Most heavy elements beyond the iron peak are synthesized via neutron capture processes. The nature of the astrophysical sites of neutron capture processes is still very unclear. In this work we explore the observational constraints of the chemical ab
Externí odkaz:
http://arxiv.org/abs/2308.01111
Autor:
Imig, Julie, Price, Cathryn, Holtzman, Jon A., Stone-Martinez, Alexander, Majewski, Steven R., Weinberg, David H., Johnson, Jennifer A., Prieto, Carlos Allende, Beaton, Rachael L., Beers, Timothy C., Bizyaev, Dmitry, Blanton, Michael R., Brownstein, Joel R., Cunha, Katia, Fernández-Trincado, José G., Feuillet, Diane K., Hasselquist, Sten, Hayes, Christian R., Jönsson, Henrik, Lane, Richard R., Lian, Jianhui, Mészáros, Szabolcs, Nidever, David L., Robin, Annie C., Shetrone, Matthew, Smith, Verne, Wilson, John C.
Publikováno v:
ApJ 954 124 (2023)
We present new maps of the Milky Way disk showing the distribution of metallicity ([Fe/H]), $\alpha$-element abundances ([Mg/Fe]), and stellar age, using a sample of 66,496 red giant stars from the final data release (DR17) of the Apache Point Observ
Externí odkaz:
http://arxiv.org/abs/2307.13887
The heavy element abundance profiles in galaxies place stringent constraint on galaxy growth and assembly history. Low-redshift galaxies generally have a negative metallicity gradient in their gas and stars. Such gradients are thought to be a natural
Externí odkaz:
http://arxiv.org/abs/2306.14100
Autor:
Pagliaro, Gianluca, Papa, Maria Alessandra, Ming, Jing, Lian, Jianhui, Tsuna, Daichi, Maraston, Claudia, Thomas, Daniel
We study the prospects for detection of continuous gravitational signals from "normal" Galactic neutron stars, i.e. non-recycled ones. We use a synthetic population generated by evolving stellar remnants in time, according to several models. We consi
Externí odkaz:
http://arxiv.org/abs/2303.04714