Search Publications
Comparative Analysis of the 2020 November 29 Solar Energetic Particle Event Observed by Parker Solar Probe
Lario, D.; Palmerio, E.; Mitchell, D. G. +15 more
We analyze two specific features of the intense solar energetic particle (SEP) event observed by Parker Solar Probe (PSP) between 2020 November 29 and 2020 December 2. The interplanetary counterpart of the coronal mass ejection (CME) on 2020 November 29 that generated the SEP event (hereafter ICME-2) arrived at PSP (located at 0.8 au from the Sun)…
Earth Wind as a Possible Exogenous Source of Lunar Surface Hydration
Wei, Y.; Zhang, H.; Xia, L. D. +22 more
Understanding the sources of lunar water is crucial for studying the history of lunar evolution, as well as the interaction of solar wind with the Moon and other airless bodies. Recent orbital spectral observations revealed that the solar wind is a significant exogenous driver of lunar surficial hydration. However, the solar wind is shielded over …
Ultramassive Black Holes in the Most Massive Galaxies: MBH-σ versus MBH-Rb
Gil de Paz, Armando; Knapen, Johan H.; Dullo, Bililign T.
We investigate the nature of the relations between black hole (BH) mass (MBH) and the central velocity dispersion (σ) and, for core-Sérsic galaxies, the size of the depleted core (Rb). Our sample of 144 galaxies with dynamically determined MBH encompasses 24 core-Sérsic galaxies, thought to be products of gas-poor …
Fundamental properties of a selected sample of Ap stars: Inferences from interferometric and asteroseismic constraints
Keszthelyi, Z.; Cunha, M. S.; Holdsworth, D. L. +2 more
Context. Magnetic fields influence the formation and evolution of stars and impact the observed stellar properties. magnetic A-type stars (Ap stars) are a prime example of this. Access to precise and accurate determinations of their stellar fundamental properties, such as masses and ages, is crucial to understand the origin and evolution of fossil…
UOCS - III. UVIT catalogue of open clusters with machine learning-based membership using Gaia EDR3 astrometry
Jadhav, Vikrant V.; Subramaniam, Annapurni; Pennock, Clara M. +2 more
We present a study of six open clusters (Berkeley 67, King 2, NGC 2420, NGC 2477, NGC 2682, and NGC 6940), using the Ultra Violet Imaging Telescope (UVIT) aboard ASTROSAT and Gaia EDR3. We used combinations of astrometric, photometric, and systematic parameters to train and supervise a machine-learning algorithm along with a Gaussian mixture model…
TESS Discovery of a Super-Earth and Three Sub-Neptunes Hosted by the Bright, Sun-like Star HD 108236
Butler, R. Paul; Kristiansen, Martti H.; Terentev, Ivan A. +59 more
We report the discovery and validation of four extrasolar planets hosted by the nearby, bright, Sun-like (G3V) star HD 108236 using data from the Transiting Exoplanet Survey Satellite (TESS). We present transit photometry, reconnaissance, and precise Doppler spectroscopy, as well as high-resolution imaging, to validate the planetary nature of the …
Consistency testing for invariance of the speed of light at different redshifts: the newest results from strong lensing and Type Ia supernovae observations
Liu, Yuting; Cao, Shuo; Biesiada, Marek +3 more
The invariance of the speed of light in the distant Universe has profound significance for fundamental physics. In this paper, we propose a new model-independent method to test the invariance of the speed of light c at different redshifts by combining the strong gravitational lensing (SGL) systems and the observations of Type Ia supernovae (SNe Ia…
Classical Novae Masquerading as Dwarf Novae? Outburst Properties of Cataclysmic Variables with ASAS-SN
Mukai, K.; Kochanek, C. S.; Stanek, K. Z. +12 more
The unprecedented sky coverage and observing cadence of the All-Sky Automated Survey for SuperNovae (ASAS-SN) has resulted in the discovery and continued monitoring of a large sample of Galactic transients. The vast majority of these are accretion-powered dwarf nova outbursts in cataclysmic variable systems, but a small subset are thermonuclear-po…
Quasi-periodic Oscillations in the TESS Light Curve of TX Col, a Diskless Intermediate Polar on the Precipice of Forming an Accretion Disk
Garnavich, Peter; Littlefield, Colin; Szkody, Paula +4 more
One of the fundamental properties of an intermediate polar is the dynamical nature of the accretion flow as it encounters the white dwarf's (WD's) magnetosphere. Many works have presumed a dichotomy between disk-fed accretion, in which the WD accretes from a Keplerian disk, and stream-fed accretion, in which the matter stream from the donor star d…
Chandra and Magellan/FIRE follow-up observations of PSO167-13: An X-ray weak QSO at z = 6.515
Bauer, F. E.; Brandt, W. N.; Vignali, C. +19 more
Context. The discovery of hundreds of quasi-stellar objects (QSOs) in the first gigayear of the Universe powered by already grown supermassive black holes (SMBHs) challenges our knowledge of SMBH formation. In particular, investigations of z > 6 QSOs that present notable properties can provide unique information on the physics of fast SMBH grow…