Search Publications

Characterization of Low-mass K2 Planet Hosts Using Near-infrared Spectroscopy
DOI: 10.3847/1538-3881/ab3347 Bibcode: 2019AJ....158..135R

Vanderburg, Andrew; Montet, Benjamin T.; Christiansen, Jessie L. +3 more

We present moderate resolution near-infrared spectra in the H, J, and K band of M-dwarf hosts to candidate transiting exoplanets discovered by NASA’s K2 mission. We employ known empirical relationships between spectral features and physical stellar properties to measure the effective temperature, radius, metallicity, and luminosity of our sample. …

2019 The Astronomical Journal
Gaia 6
Deuterated methanol toward NGC 7538-IRS1
DOI: 10.1051/0004-6361/201834948 Bibcode: 2019A&A...627A..80O

Fedele, D.; Favre, C.; Lefloch, B. +7 more

We investigate the deuteration of methanol towards the high-mass star-forming region NGC 7538-IRS1. We carried out a multi-transition study of CH3OH, 13CH3OH, and the deuterated flavors, CH2DOH and CH3OD, between 1.0 and 1.4 mm with the IRAM-30 m antenna. In total, 34 13CH3

2019 Astronomy and Astrophysics
Herschel 6
Variability of Precipitating Ion Fluxes During the September 2017 Event at Mars
DOI: 10.1029/2018JA026123 Bibcode: 2019JGRA..124..420M

Holmström, M.; Leblanc, F.; Luhmann, J. +15 more

In this work, we study the influence of the September 2017 solar event on the precipitating heavy ion fluxes toward Mars' atmosphere as seen by Mars Atmosphere and Volatile EvolutioN/Solar Wind Ion Analyzer, an energy and angular ion spectrometer and by Mars Atmosphere and Volatile EvolutioN/Suprathermal and Thermal Ion Composition instrument, an …

2019 Journal of Geophysical Research (Space Physics)
MEx 6
Awakening of the Fast-spinning Accreting Be/X-Ray Pulsar A0538-66
DOI: 10.3847/2041-8213/ab32f0 Bibcode: 2019ApJ...881L..17D

Mereghetti, Sandro; Santangelo, Andrea; Ducci, Lorenzo

A0538-66 is a Be/X-ray binary (Be/XRB) hosting a 69 ms pulsar It emitted bright X-ray outbursts with peak luminosity up to ∼1039 erg s-1 during the first years after its discovery in 1977. Since then, it was always seen in quiescence or during outbursts with L x ≲ 4 × 1037 erg s-1. In 2018 we …

2019 The Astrophysical Journal
XMM-Newton 6
A Multi-epoch X-Ray Study of the Spiral Galaxy NGC 7331
DOI: 10.3847/1538-4357/ab2461 Bibcode: 2019ApJ...879..112J

Kong, Albert K. H.; Jin, Ruolan

X-ray point sources in galaxies are dominated by X-ray binaries (XRBs) that are variables or transients, and whether their variability would alter the X-ray luminosity functions (XLFs) is still in debate. Here we report on NGC 7331 as an example to test this with seven Chandra observations. Their detection limit is 7 × 1037 erg s-1…

2019 The Astrophysical Journal
XMM-Newton eHST 6
Runaway O-star Bow Shocks as Particle Accelerators? The Case of AE Aur Revisited
DOI: 10.3847/1538-4357/ab43e5 Bibcode: 2019ApJ...885..105R

Rangelov, Blagoy; Federman, S. R.; Montmerle, Thierry +2 more

We present results of our Chandra/ACIS observations of the field centered on the fast, runaway O star AE Aur and its bow shock. Previous XMM-Newton observations revealed an X-ray “blob” near the IR arc tracing the bow shock, possibly a nonthermal source consistent with models of Inverse Compton scattering of dust IR photons by electrons accelerate…

2019 The Astrophysical Journal
XMM-Newton 6
Spectroscopy of NGC 4258 Globular Cluster Candidates: Membership Confirmation and Kinematics
DOI: 10.3847/1538-4357/ab113a Bibcode: 2019ApJ...876...39G

González-Lópezlira, Rosa A.; Georgiev, Iskren Y.; Loinard, Laurent +9 more

We present multiobject spectroscopic observations of 23 globular cluster candidates (GCCs) in the prototypical megamaser galaxy NGC 4258, carried out with the Optical System for Imaging and low-Intermediate-Resolution Integrated Spectroscopy instrument at the 10.4 m Gran Telescopio Canarias. The candidates have been selected based on the (u* - i‧)…

2019 The Astrophysical Journal
eHST 6
Cassini UVIS Detection of Saturn's North Polar Hexagon in the Grand Finale Orbits
DOI: 10.1029/2019JE005922 Bibcode: 2019JGRE..124.1979P

Lamy, L.; West, R. A.; Esposito, L. W. +6 more

Cassini's final orbits in 2016 and 2017 provided unprecedented spatial resolution of Saturn's polar regions from near-polar spacecraft viewing geometries. Long-wavelength channels of Cassini's Ultraviolet Imaging Spectrograph instrument detected Saturn's UV-dark north polar hexagon near 180 nm at planetocentric latitudes near 75°N. The dark polar …

2019 Journal of Geophysical Research (Planets)
Cassini 6
X-ray and radio studies of SNR CTB 37B hosting the magnetar CXOU J171405.7-381031
DOI: 10.1093/mnras/stz1656 Bibcode: 2019MNRAS.487.5019B

Safi-Harb, Samar; Kothes, Roland; Gotthelf, Eric V. +2 more

We present a Chandra and XMM-Newton study of the supernova remnant (SNR) CTB 37B, along with archival radio observations. In radio wavelengths, the SNR CTB 37B is an incomplete shell showing bright emission from the eastern side, while the X-ray morphology shows diffuse emission from regions surrounding the magnetar CXOU J171405.7-381031. We used …

2019 Monthly Notices of the Royal Astronomical Society
XMM-Newton 6
Multifractal detrended moving average analysis of Kepler stars with surface differential rotation traces
DOI: 10.1093/mnras/stz1791 Bibcode: 2019MNRAS.488.3274D

De Medeiros, J. R.; de Freitas, D. B.; Das Chagas, M. L. +2 more

A multifractal formalism is employed to analyse high-precision time-series data of Kepler stars with surface differential rotation (DR) traces. The multifractal detrended moving average (MFDMA) algorithm has been explored to characterize the multiscale behaviour of the observed time series from a sample of 662 stars selected with parameters close …

2019 Monthly Notices of the Royal Astronomical Society
SOHO 6