Search Publications

Broad-velocity-width Molecular Features in the Galactic Plane
DOI: 10.3847/1538-4357/abd556 Bibcode: 2021ApJ...908..246Y

Oka, Tomoharu; Tsujimoto, Shiho; Iwata, Yuhei +2 more

We performed a systematic search for broad-velocity-width molecular features (BVFs) in the disk part of our Galaxy by using the CO J = 1-0 survey data obtained with the Nobeyama Radio Observatory 45 m telescope. From this search, 58 BVFs were identified. In comparisons with the infrared and radio continuum images, 36 BVFs appeared to have both inf…

2021 The Astrophysical Journal
AKARI 2
Say Hello to Algol's New Companion Candidates
DOI: 10.3847/1538-4357/ac1351 Bibcode: 2021ApJ...920..137J

Jetsu, Lauri

Constant orbital period ephemerides of eclipsing binaries give the computed eclipse epochs (C). These ephemerides based on the old data cannot accurately predict the observed future eclipse epochs (O). Predictability can be improved by removing linear or quadratic trends from the O - C data. Additional companions in an eclipsing binary system caus…

2021 The Astrophysical Journal
Gaia 2
Numerical Study of Two Injection Methods for the 2007 November 15 Coronal Mass Ejection in the Inner Heliosphere
DOI: 10.3847/1538-4357/ac0b3f Bibcode: 2021ApJ...918...35Z

Shen, Fang; Feng, Xueshang; Zhang, Man +1 more

In this paper, we use two injection methods, i.e., coronal mass ejection (CME) with and without radial compression, to investigate the propagation of the 2007 November 15 CME in the inner heliosphere with a three-dimensional, time-dependent, numerical magnetohydrodynamic model. In order to reproduce the large-scale interplanetary magnetic field as…

2021 The Astrophysical Journal
SOHO 2
Spatially Highly Resolved Solar-wind-induced Magnetic Field on Venus
DOI: 10.3847/1538-4357/ac2836 Bibcode: 2021ApJ...923...73H

He, Maosheng; Vogt, Joachim; Zhang, Tielong +2 more

The current work investigates the Venusian solar-wind-induced magnetosphere at a high spatial resolution using all Venus Express (VEX) magnetic observations through an unbiased statistical method. We first evaluate the predictability of the interplanetary magnetic field (IMF) during VEX's Venusian magnetospheric transits and then map the induced f…

2021 The Astrophysical Journal
VenusExpress 2
Detection of H2 in the TWA 7 System: A Probable Circumstellar Origin
DOI: 10.3847/1538-4357/ac1d4c Bibcode: 2021ApJ...921...86F

France, Kevin; Johns-Krull, Christopher M.; Carpenter, John M. +4 more

Using HST-COS far-UV spectra, we have discovered warm molecular hydrogen in the TWA 7 system. TWA 7, a ~9 Myr old M2.5 star, has a cold debris disk and has previously shown no signs of accretion. Molecular hydrogen is expected to be extremely rare in a debris disk. While molecular hydrogen can be produced in starspots or the lower chromospheres of…

2021 The Astrophysical Journal
Gaia eHST 2
Spitzer Mid-infrared Study of Sh 2-208: Evolution of Protoplanetary Disks in Low-metallicity Environments
DOI: 10.3847/1538-4357/abf8b7 Bibcode: 2021ApJ...914..115Y

Yasui, Chikako

This study presents sensitive mid-infrared (MIR) photometry obtained with the Spitzer/IRAC for a young cluster in Sh 2-208 (S208) located in one of the lowest-metallicity H II regions in the Galaxy, $[{\rm{O}}/{\rm{H}}]=-0.8$ dex. Previous studies suggested that the cluster is ~0.5 Myr old and has a distance of D = 4 kpc, which is consistent with …

2021 The Astrophysical Journal
Gaia 2
Implications of the Low-frequency Turnover in the Spectrum of Radio Knot C in DG Tau
DOI: 10.3847/1538-4357/ac2b26 Bibcode: 2021ApJ...923...61B

Björnsson, C. -I.

The synchrotron spectrum of radio knot C in the protostellar object DG Tau has a low-frequency turnover. This is used to show that its magnetic field strength is likely to be at least 10 mG, which is roughly two orders of magnitude larger than previously estimated. The earlier, lower value is due to an overestimate of the emission volume together …

2021 The Astrophysical Journal
Gaia 2
Chandra X-Ray Observations of V830 Tau: A T Tauri Star Hosting an Evanescent Planet
DOI: 10.3847/1538-4357/ac111a Bibcode: 2021ApJ...920...22S

Skinner, Stephen L.; Güdel, Manuel

The radial velocity study by Donati et al. (2016) reported the detection of a close-in giant planet in a 4.93 day orbit around the ~2 Myr old weak-lined T Tauri star V830 Tau. Because of the stringent timescale constraints that a very young host star like V830 Tau would place on hot-Jupiter formation models and inward-migration mechanisms, indepen…

2021 The Astrophysical Journal
Gaia 2
XMM Observation of the Supernova Remnant J0454-6713 and the Adjacent N9 Superbubble
DOI: 10.3847/1538-4357/abd561 Bibcode: 2021ApJ...909...13S

Foster, Adam R.; Smith, Randall K.; Points, Sean D. +1 more

The Large Magellanic Cloud supernova remnant J0454-6713 abutting the H II region N9 has been observed with XMM-Newton. Two groups of lines from Fe XVII account for half the emission and lines from Fe XVIII, O VII, and O VIII are also clearly detected with the XMM RGS. Isothermal equilibrium fits of the EPIC spectra reproduce the basic spectral for…

2021 The Astrophysical Journal
XMM-Newton 2
The Effects of Magnetic Boundary on the Uniform Distribution of Energetic Particle Intensities Observed by Multiple Spacecraft
DOI: 10.3847/1538-4357/abf9a4 Bibcode: 2021ApJ...913...66W

Wang, Yang; Lyu, Dan; Xiao, Boxi +1 more

In the decay phase of solar energetic particle (SEP) events, particle intensities observed by widely separated spacecraft usually present comparable intensities (within a factor of 2-3) that evolve similarly in time. The phenomenon of SEP events is called a reservoir, which could be observed frequently in intensive gradual SEP events. In this work…

2021 The Astrophysical Journal
Ulysses 2