Search Publications

Space Telescope and Optical Reverberation Mapping Project. X. Understanding the Absorption-line Holiday in NGC 5548
DOI: 10.3847/1538-4357/ab1b48 Bibcode: 2019ApJ...877..119D

Brandt, W. N.; Knigge, C.; Kriss, G. A. +27 more

The Space Telescope and Optical Reverberation Mapping Project (AGN STORM) on NGC 5548 in 2014 is one of the most intensive multiwavelength AGN monitoring campaigns ever. For most of the campaign, the emission-line variations followed changes in the continuum with a time lag, as expected. However, the lines varied independently of the observed UV-o…

2019 The Astrophysical Journal
eHST 41
The Relationship between Galaxy ISM and Circumgalactic Gas Metallicities
DOI: 10.3847/1538-4357/ab4c3c Bibcode: 2019ApJ...886...91K

Charlton, Jane C.; Kacprzak, Glenn G.; Churchill, Christopher W. +3 more

We present interstellar matter (ISM) and circumgalactic medium (CGM) metallicities for 25 absorption systems associated with isolated star-forming galaxies (≤ft< z\right> =0.28) with 9.4 ≤ log(M */M ) ≤ 10.9 and with absorption detected within (200 kpc). Galaxy ISM metallicities were measured using Hα/[N II] emission l…

2019 The Astrophysical Journal
eHST 41
Complex Rotational Modulation of Rapidly Rotating M Stars Observed with TESS
DOI: 10.3847/1538-4357/ab158c Bibcode: 2019ApJ...876..127Z

Dai, F.; Rowden, P.; Seager, S. +23 more

We have searched for short periodicities in the light curves of stars with T eff cooler than 4000 K made from 2-minute cadence data obtained in Transiting Exoplanet Survey Satellite sectors 1 and 2. Herein we report the discovery of 10 rapidly rotating M dwarfs with highly structured rotational modulation patterns among 371 M dwarfs fou…

2019 The Astrophysical Journal
Gaia 41
Demonstration of Magnetic Field Tomography with Starlight Polarization toward a Diffuse Sightline of the ISM
DOI: 10.3847/1538-4357/aafdb2 Bibcode: 2019ApJ...872...56P

Tassis, Konstantinos; Potter, Stephen B.; Liodakis, Ioannis +7 more

The availability of large data sets with stellar distance and polarization information will enable a tomographic reconstruction of the (plane-of-the-sky-projected) interstellar magnetic field in the near future. We demonstrate the feasibility of such a decomposition within a small region of the diffuse interstellar medium (ISM). We combine measure…

2019 The Astrophysical Journal
Gaia 41
New Millimeter CO Observations of the Gas-rich Debris Disks 49 Cet and HD 32297
DOI: 10.3847/1538-4357/ab4272 Bibcode: 2019ApJ...884..108M

Pascucci, Ilaria; Hughes, A. Meredith; Moór, Attila +7 more

Previous observations revealed the existence of CO gas at nearly protoplanetary level in several dust-rich debris disks around young A-type stars. Here we used the Atacama Large Millimeter/submillimeter Array (ALMA) 7 m Array to measure 13CO and C18O emission toward two debris disks, 49 Cet and HD 32297, and detected similarl…

2019 The Astrophysical Journal
Gaia 41
Properties of Slow Magnetoacoustic Oscillations of Solar Coronal Loops by Multi-instrumental Observations
DOI: 10.3847/2041-8213/ab0c9f Bibcode: 2019ApJ...874L...1N

Moon, Y. -J.; Nakariakov, V. M.; Kumar, P. +3 more

Rapidly decaying oscillations of the thermal emission detected in the decay phase of solar and stellar flares are usually interpreted as standing or sloshing (reflecting) slow magnetoacoustic oscillations. We determine the scalings of the oscillation periods, damping times, and amplitudes with the temperature, considering both standing and sloshin…

2019 The Astrophysical Journal
Hinode SOHO 41
UVIT Open Cluster Study. II. Detection of Extremely Low Mass White Dwarfs and Post-Mass Transfer Binaries in M67
DOI: 10.3847/1538-4357/ab4b43 Bibcode: 2019ApJ...886...13J

Jadhav, Vikrant V.; Subramaniam, Annapurni; Sindhu, N.

A detailed study of the UV-bright stars in the old open star cluster M67 is presented based on the far-UV observations using the Ultra Violet Imaging Telescope (UVIT) on ASTROSAT. The UV and UV-optical color-magnitude diagrams (CMDs), along with overlaid isochrones, are presented for the member stars, which include blue straggler stars (BSSs), tri…

2019 The Astrophysical Journal
Gaia 41
Chemical Abundances along the 1G Sequence of the Chromosome Maps: The Globular Cluster NGC 3201
DOI: 10.3847/1538-4357/ab53d9 Bibcode: 2019ApJ...887...91M

Milone, A. P.; Cordoni, G.; Marino, A. F. +10 more

The Hubble Space Telescope (HST) UV Legacy Survey of Galactic Globular Clusters (GCs) has investigated multiple stellar populations by means of the “chromosome map” (ChM) diagnostic tool that maximizes the separation between stars with different chemical compositions. One of the most challenging features revealed by ChM analysis is the apparent in…

2019 The Astrophysical Journal
eHST 40
Neutral Gas Properties and Lyα Escape in Extreme Green Pea Galaxies
DOI: 10.3847/1538-4357/ab08eb Bibcode: 2019ApJ...874...52M

Jaskot, Anne E.; Yun, Min S.; Dowd, Tara +3 more

Mechanisms regulating the escape of Lyα photons and ionizing radiation remain poorly understood. To study these processes, we analyze Very Large Array 21 cm observations of one Green Pea (GP), J160810+352809 (hereafter J1608), and Hubble Space Telescope Cosmic Origins Spectrograph (COS) spectra of 17 GP galaxies at z< 0.2. All are highly ionize…

2019 The Astrophysical Journal
eHST 40
Tensile Strength of Porous Dust Aggregates
DOI: 10.3847/1538-4357/ab09f7 Bibcode: 2019ApJ...874..159T

Kataoka, Akimasa; Tatsuuma, Misako; Tanaka, Hidekazu

Comets are thought to have information about the formation process of our solar system. Recently, detailed information about comet 67P/Churyumov-Gerasimenko was found by Rosetta. It is remarkable that its tensile strength was estimated. In this paper, we measure and formulate the tensile strength of porous dust aggregates using numerical simulatio…

2019 The Astrophysical Journal
Rosetta 40