Search Publications

Unveiling the Physical Conditions in NGC 6910
DOI: 10.3847/1538-4357/ab9122 Bibcode: 2020ApJ...896...29K

Sharma, Saurabh; Panwar, Neelam; Kaur, Harmeen +3 more

Deep and wide-field optical photometric observations along with multiwavelength archival data sets have been employed to study the physical properties of the cluster NGC 6910. The study also examines the impact of massive stars on their environment. The age, distance, and reddening of the cluster are estimated to be ∼4.5 Myr, 1.72 ± 0.08 kpc, and …

2020 The Astrophysical Journal
Gaia 17
Space Telescope and Optical Reverberation Mapping Project. XI. Disk-wind Characteristics and Contributions to the Very Broad Emission Lines of NGC 5548
DOI: 10.3847/1538-4357/ab9cb2 Bibcode: 2020ApJ...898..141D

Brandt, W. N.; Kriss, G. A.; Mehdipour, M. +22 more

In 2014 the NGC 5548 Space Telescope and Optical Reverberation Mapping campaign discovered a two-month anomaly when variations in the absorption and emission lines decorrelated from continuum variations. During this time the soft X-ray part of the intrinsic spectrum had been strongly absorbed by a line-of-sight (LOS) obscurer, which was interprete…

2020 The Astrophysical Journal
XMM-Newton eHST 17
The halo of M 105 and its group environment as traced by planetary nebula populations. I. Wide-field photometric survey of planetary nebulae in the Leo I group
DOI: 10.1051/0004-6361/202038009 Bibcode: 2020A&A...642A..46H

Freeman, K. C.; Gerhard, O.; Coccato, L. +6 more

Context. M 105 (NGC 3379) is an early-type galaxy in the Leo I group. The Leo I group is the nearest group that contains all main galaxy types and can thus be used as a benchmark to study the properties of the intra-group light (IGL) in low-mass groups.
Aims: We present a photometric survey of planetary nebulae (PNe) in the extended halo of t…

2020 Astronomy and Astrophysics
eHST 17
Jovian Auroral Ion Precipitation: X-Ray Production From Oxygen and Sulfur Precipitation
DOI: 10.1029/2019JA027007 Bibcode: 2020JGRA..12527007H

Cravens, T. E.; Mauk, B. H.; Dunn, W. R. +6 more

Many attempts have been made to model X-ray emission from both bremsstrahlung and ion precipitation into Jupiter's polar caps. Electron bremsstrahlung modeling has fallen short of producing the total overall power output observed by Earth-orbit-based X-ray observatories. Heavy ion precipitation was able to reproduce strong X-ray fluxes, but the pr…

2020 Journal of Geophysical Research (Space Physics)
XMM-Newton 17
Stellar atmospheric parameters of FGK-type stars from high-resolution optical and near-infrared CARMENES spectra
DOI: 10.1093/mnras/staa058 Bibcode: 2020MNRAS.492.5470M

Nagel, E.; Amado, P. J.; Caballero, J. A. +10 more

With the purpose of assessing classic spectroscopic methods on high-resolution and high signal-to-noise ratio spectra in the near-infrared wavelength region, we selected a sample of 65 F-, G-, and K-type stars observed with CARMENES, the new, ultra-stable, double-channel spectrograph at the 3.5 m Calar Alto telescope. We computed their stellar atm…

2020 Monthly Notices of the Royal Astronomical Society
Gaia 17
Peculiarities in the Horizontal Branch Stars of Globular Cluster NGC 1851: Discovery of a Blue Straggler Companion to an EHB Star
DOI: 10.3847/1538-4357/abc173 Bibcode: 2020ApJ...905...44S

Yadav, R. K. S.; Sahu, Snehalata; Subramaniam, Annapurni +1 more

We present a study of far-UV (FUV) bright horizontal branch (HB) stars to understand the peculiarities seen in the HB sequence of the globular cluster NGC 1851, using ground- and space-based multiwavelength data. Optical and UV color-magnitude diagrams are used to classify HB stars and their membership from Hubble Space Telescope and Gaia DR2 data…

2020 The Astrophysical Journal
Gaia eHST 17
ALMA Reveals the Molecular Gas Properties of Five Star-forming Galaxies across the Main Sequence at 3
DOI: 10.3847/1538-4357/ab7452 Bibcode: 2020ApJ...891...83C

Schinnerer, Eva; Tasca, Lidia; Liu, Daizhong +17 more

We present the detection of CO (5-4) with signal-to-noise ratio (S/N) > 7-13 and a lower CO transition with S/N > 3 (CO (4-3) for four galaxies, and CO (3-2) for one) with the Atacama Large Millimeter/submillimeter Array in bands 3 and 4 in five main-sequence (MS) star-forming galaxies with stellar masses (3-6) × 1010M

2020 The Astrophysical Journal
eHST 17
Orbital Modulation of Gamma Rays from PSR J2339-0533
DOI: 10.3847/1538-4357/ab93ba Bibcode: 2020ApJ...897...52A

An, Hongjun; Kerr, Matthew; Fermi-LAT Collaboration +1 more

We report on orbital modulation of the 100-600 MeV gamma-ray emission of the PB = 4.6 hr millisecond pulsar binary PSR J2339-0533 using 11 yr of Fermi Large Area Telescope data. The modulation has high significance (chance probability p ≈ 10-7), is approximately sinusoidal, peaks near pulsar superior conjunction, and is detec…

2020 The Astrophysical Journal
Gaia 17
Chemical abundances of open clusters from high-resolution infrared spectra - II. NGC 752
DOI: 10.1093/mnras/stz3008 Bibcode: 2020MNRAS.491..544B

Sneden, C.; Pilachowski, C. A.; Mace, G. N. +9 more

We present a detailed near-infrared chemical abundance analysis of 10 red giant members of the Galactic open cluster NGC 752. High-resolution (R ≃ 45000) near-infrared spectral data were gathered with the Immersion Grating Infrared Spectrograph, providing simultaneous coverage of the complete H and K bands. We derived the abundances of H-burning (…

2020 Monthly Notices of the Royal Astronomical Society
Gaia 17
The PDR structure and kinematics around the compact H II regions S235 A and S235 C with [C II], [13C II], [O I], and HCO+ line profiles
DOI: 10.1093/mnras/staa2142 Bibcode: 2020MNRAS.497.2651K

Schneider, N.; Samal, M. R.; Okada, Y. +11 more

The aim of this work is to study structure and gas kinematics in the photodissociation regions (PDRs) around the compact H II regions S235 A and S235 C. We observe the [C II], [13C II], and [O I] line emission, using SOFIA/upGREAT, and complement them by data of HCO+ and CO. We use the [13C II] line to measure the …

2020 Monthly Notices of the Royal Astronomical Society
Gaia 17