Results 51 to 60 of about 72 (61)

Multi-Observatory Research of Young Stellar Energetic Flares (MORYSEF): X-Ray-flare-related Phenomena and Multi-epoch Behavior

The Astrophysical Journal
The most powerful stellar flares driven by magnetic energy occur during the early pre-main-sequence (PMS) phase. The Orion Nebula represents the nearest region populated by young stars, showing the greatest number of flares accessible to a single ...
Konstantin V. Getman, Eric D. Feigelson, Abygail R. Waggoner, L. Ilsedore Cleeves, Jan Forbrich, Joe P. Ninan, Oleg Kochukhov, Vladimir S. Airapetian, Sergio A. Dzib, Charles J. Law, Christian Rab   +10 more
doaj   +1 more source

Probing the Stellar Populations and Star Formation History of Early-type Galaxies at 0 < z < 1.1 in the Rest-frame Ultraviolet

The Astrophysical Journal
We measure the evolution of the rest-frame near-ultraviolet (NUV)− V colors for early-type galaxies in clusters at 0 < z < 1.1 using data from the Hyper Suprime-Cam Subaru Strategic Program, CFHT Large Area U -band Deep Survey, and local Sloan Digital ...
Sadman S. Ali, Roberto De Propris, Chul Chung, Steven Phillipps, Malcolm N. Bremer, Masato Onodera, Marcin Sawicki, Guillaume Desprez, Stephen Gwyn   +8 more
doaj   +1 more source

The First Exploration of the Correlations Between WISE 12 μm and CO Emission in Early-type Galaxies

The Astrophysical Journal
We present the analysis of a comprehensive sample of 352 early-type galaxies using public data, to investigate the correlations between CO luminosities and mid-infrared luminosities observed by Wide-field Infrared Survey Explorer.
Yang Gao, Enci Wang, Qing-Hua Tan, Timothy A. Davis, Fu-Heng Liang, Xue-Jian Jiang, Ning Gai, Qian Jiao, DongDong Shi, Shuai Feng, Yanke Tang, Shijie Li, Yi-Fan Wang   +12 more
doaj   +1 more source

A Flare-related Decimetric Type-IV Radio Burst Induced by the X2 Radiation of Electron Cyclotron Maser Emission

The Astrophysical Journal Letters
The radiation mechanism of decimetric wideband and pulsating radio bursts from the Sun (in terms of decimetric type-IV (t-IVdm) burst) and other flaring stars is a long-standing problem.
Maoshui Lv, Ze Zhong, Xiangliang Kong, Hao Ning, Feiyu Yu, Bing Wang, Baolin Tan, Victor Melnikov, Alexey Kuznetsov, Hongqiang Song, Ruisheng Zheng, Yao Chen   +11 more
doaj   +1 more source

A Long-duration Superflare on the K Giant HD 251108

The Astrophysical Journal
Many giant stars are magnetically active, which causes rotational variability, chromospheric emission lines, and X-ray emission. Large outbursts in these emission features can set limits on the magnetic field strength and thus constrain the mechanism of ...
Hans Moritz Günther, Dheeraj Pasham, Alexander Binks, Stefan Czesla, Teruaki Enoto, Michael Fausnaugh, Franz-Josef Hambsch, Shun Inoue, Hiroyuki Maehara, Yuta Notsu, Jan Robrade, J. H. M. M. Schmitt, P. C. Schneider   +12 more
doaj   +1 more source

Do Young Suns Produce Frequent, Massive CMEs? Results from Five-year Dedicated Optical Observations of EK Draconis and V889 Hercules

The Astrophysical Journal
We report results from a five-year (132-night) dedicated observational campaign targeting two nearby young solar-type stars, EK Draconis (∼50–125 Myr age) and V889 Hercules (∼30 Myr age), using the 3.8 m Seimei Telescope and Transiting Exoplanet Survey ...
Kosuke Namekata, Hiroyuki Maehara, Yuta Notsu, Satoshi Honda, Kai Ikuta, Daisaku Nogami, Kazunari Shibata   +6 more
doaj   +1 more source

The Photometric Variability and Spectrum of the Hot Post-AGB Star IRAS 21546+4721

Galaxies
We present the results of photometric and spectroscopic observations of a poorly studied B-type supergiant with infrared excess, the hot post-AGB star IRAS 21546+4721.
Natalia Ikonnikova, Marina Burlak, Alexander Dodin   +2 more
doaj   +1 more source

Ionization Sources of the Local Interstellar Clouds: Two B Stars, Three White Dwarfs, and the Local Hot Bubble

The Astrophysical Journal
The dominant sources of photoionizing radiation in the extreme-ultraviolet (EUV) incident on the exterior of the local interstellar clouds include two nearby early B-type stars, ϵ CMa (124 ± 2 pc) and β CMa (151 ± 5 pc), three hot dwarfs, and the Local ...
J. Michael Shull, Rachel M. Curran, Michael W. Topping, Jonathan D. Slavin   +3 more
doaj   +1 more source

Ultraviolet Radiation and Neutrinos: Two Messengers from CCSNe in the CSM Scenario

The Astrophysical Journal
Massive stars (>8 M _⊙ ) often undergo intense mass loss through winds or eruptive events in the final stages of their evolution, leading to the formation of a dense circumstellar medium (CSM). This material, expelled months to years before core collapse,
Silvia Gagliardini, Simone Dall’Osso, Dafne Guetta, Angela Zegarelli, Silvia Celli, Antonio Capone, Irene Di Palma   +6 more
doaj   +1 more source

Asymmetries and Circumstellar Interaction in the Type II SN 2024bch

The Astrophysical Journal
We present a comprehensive multi-epoch photometric and spectroscopic study of SN 2024bch, a nearby (19.9 Mpc) Type II supernova (SN) with prominent early high-ionization emission lines.
Jennifer E. Andrews, Manisha Shrestha, K. Azalee Bostroem, Yize Dong, Jeniveve Pearson, M. M. Fausnaugh, David J. Sand, S. Valenti, Aravind P. Ravi, Emily Hoang, Griffin Hosseinzadeh, Ilya Ilyin, Daryl Janzen, M. J. Lundquist, Nicolás Meza, Nathan Smith, Saurabh W. Jha, Moira Andrews, Joseph Farah, Estefania Padilla Gonzalez, D. Andrew Howell, Curtis McCully, Megan Newsome, Craig Pellegrino, Giacomo Terreran, Patrick Wiggins, Brian Hsu, Collin T. Christy, Noah Franz, Xiaofeng Wang, Jialian Liu, Liyang Chen   +31 more
doaj   +1 more source