Search Publications
Properties of the Diffuse Emission around Warm Loops in Solar Active Regions
Brooks, David H.
Coronal loops in active regions are the subjects of intensive investigation, but the important diffuse unresolved emission in which they are embedded has received relatively little attention. Here I measure the densities and emission measure (EM) distributions of a sample of background-foreground regions surrounding warm (2 MK) coronal loops, and …
The Eruption of Outer Spine-like Loops Leading to a Double-stage Circular-ribbon Flare
Liu, Chang; Wang, Haimin; Lee, Jeongwoo
Circular-ribbon flares occur in a confined magnetic structure, but can also be associated with coronal mass ejections (CMEs) when a filament embedded under the fan erupts. Here we study an M8.7 circular-ribbon flare (SOL2014-12-17T04:51), which is accompanied by a CME yet without a clear indication of filament eruption. Using a nonlinear force-fre…
A particular carbon-chain-producing region: L1489 starless core
Kim, Kee-Tae; Liu, Tie; Yuan, Jinghua +14 more
We detected carbon-chain molecules (CCMs) HC2n+1N (n = 1-3) and C3S in Ku band as well as high-energy excitation lines including C4H N = 9-8, J = 17/2-15/2, 19/2-17/2, and CH3CCH J = 5-4, K = 2 in the 3 mm band toward a starless core called the eastern molecular core (EMC) of L1489 IRS. Maps o…
When Does the Onset of Multiple Stellar Populations in Star Clusters Occur. II. No Evidence of Multiple Stellar Populations in Lindsay 113
Milone, Antonino P.; Li, Chengyuan; Wang, Yue
The presence of multiple populations (MPs) in almost all globular clusters (GCs) older than ∼10 Gyr has drawn lots of attention. Recently, cumulative evidence has indicated that extragalactic GCs that are older than 2 Gyr seem to also harbor MPs; however, those that are younger than 2 Gyr do not. These observations seem to imply that age is a prim…
The G305 Star-forming Region. I. Newly Classified Hot Stars
Kounkel, Marina; Minniti, Dante; Stringfellow, Guy +12 more
The relatively nearby star-forming complex G305 is one of the most luminous H II regions in the Galaxy, and it contains several sites and epochs of star formation. Using a combination of near-infrared photometry from “Vista Variables in Via Lactea” ESO Large Public Survey, SDSS-IV APOGEE-2 spectra, and Gaia DR2 photometry and astrometry, we report…
Solar jet-like features rooted in flare ribbons
Hou, Yijun; Yang, Shuhong; Zhang, Jun +1 more
Employing the high spatio-temporal Interface Region Imaging Spectrograph 1330 Å observations, we investigated the jet-like features that occurred during the X8.2 class flare in NOAA active region (AR) 12673 on 2017 September 10. These jet-like features were rooted in the flare ribbons. We examined 15 features, and the mean values of the lifetimes,…
Estimation of singly transiting K2 planet periods with Gaia parallaxes
Jordán, Andrés; Espinoza, Néstor; Brahm, Rafael +1 more
When a planet is only observed to transit once, direct measurement of its period is impossible. It is possible, however, to constrain the periods of single transiters, and this is desirable as they are likely to represent the cold and far extremes of the planet population observed by any particular survey. Improving the accuracy with which the per…
Imaging Observations of Chromospheric Evaporation in a Circular-ribbon Flare
Huang, Y.; Li, D.; Zhang, Q. M.
In this paper, we report our multiwavelength imaging observations of chromospheric evaporation in a C5.5 circular-ribbon flare (CRF) on 2014 August 24. The flare was observed by the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory, the X-ray Telescope (XRT) on board the Hinode spacecraft, and the ground-based Nobeyama Rad…
BRITE photometry of the massive post-RLOF system HD149 404
Gosset, E.; Handler, G.; Wade, G. A. +12 more
Context. HD 149 404 is an evolved non-eclipsing O-star binary that has previously undergone a Roche lobe overflow interaction.
Aims: Understanding some key properties of the system requires a determination of the orbital inclination and of the dimensions of the components.
Methods: The BRITE-Heweliusz satellite was used to collect photom…
The Milky Way like galaxy NGC 6384 and its nuclear star cluster at high NIR spatial resolution using LBT/ARGOS commissioning data
Neumayer, Nadine; Georgiev, Iskren Y.; Baumgardt, Holger +11 more
We analyse high spatial resolution near infrared (NIR) imaging of NGC 6384, a Milky Way like galaxy, using ARGOS commissioning data at the Large Binocular Telescope (LBT). ARGOS provides a stable PSFFWHM = 0{^''.}2-0{^''.}3 AO correction of the ground layer across the LUCI 2 NIR camera 4 × 4 arcmin field by using s…