Search Publications
Strongly pulsed thermal X-rays from a single extended hot spot on PSR J2021+4026
Mereghetti, Sandro; Turolla, Roberto; Rigoselli, Michela +2 more
The radio-quiet pulsar PSR J2021+4026 is mostly known because it is the only rotation-powered pulsar that shows variability in its γ-ray emission. Using XMM-Newton archival data, we first confirmed that its flux is steady in the X-ray band, and then we showed that both the spectral and timing X-ray properties, that is to say the narrow pulse profi…
Observations of Closed Magnetic Flux Embedded in the Lobes During Periods of Northward IMF
Fear, R. C.; Coxon, J. C.; Fryer, L. J. +1 more
The high latitude, lobe regions of the magnetosphere are often assumed to contain cool, low energy plasma populations. However, during periods of northward Interplanetary Magnetic Field, energetic plasma populations have occasionally been observed. We present three cases when Cluster observed uncharacteristically "hot" plasma populations in the lo…
Magnetic Reconnection in the Near-Earth Magnetotail
Nagai, Tsugunobu
Non-equilibrium in the solar neighbourhood using dynamical modelling with Gaia DR2
Kipper, Rain; Tenjes, Peeter; Tempel, Elmo +1 more
Matter distribution models of the Milky Way galaxy are usually stationary, although there are known to be wave-like perturbations in the disc at ~10 per cent level of the total density. Modelling of the overall acceleration field by allowing non-equilibrium is a complicated task. We must learn to distinguish whether density enhancements are persis…
Rapid CO gas dispersal from NO Lup's class III circumstellar disc
Testi, L.; Tazzari, M.; Williams, J. P. +9 more
We observed the K7 class III star NO Lup in an ALMA survey of the 1-3 Myr Lupus association and detected circumstellar dust and CO gas. Here we show that the J = 3-2 CO emission is both spectrally and spatially resolved, with a broad velocity width ~19 km s-1 for its resolved size ~1 arcsec (~130 au). We model the gas emission as a Kepl…
BVRI Photometric Observations, Light Curve Solutions and Orbital Period Analysis of BF Pav
Davoudi, Fatemeh; Poro, Atila; Blackford, Mark G. +7 more
A new ephemeris, period change analysis and light curve modeling of the W UMa-type eclipsing binary BF Pav are presented in this study. Light curves of the system taken in BVRI filters from two observatories, in Australia and Argentina, were modeled using the Wilson-Devinney code. The results of this analysis demonstrate that BF Pav is a contact b…
A survey for variable young stars with small telescopes - IV. Rotation periods of YSOs in IC 5070
Scholz, Aleks; Eislöffel, Jochen; Price, Mark C. +50 more
Studying rotational variability of young stars is enabling us to investigate a multitude of properties of young star-disc systems. We utilize high cadence, multiwavelength optical time series data from the Hunting Outbursting Young Stars citizen science project to identify periodic variables in the Pelican Nebula (IC 5070). A double blind study us…
Core Mass Estimates in Strong Lensing Galaxy Clusters: A Comparison between Masses Obtained from Detailed Lens Models, Single-halo Lens Models, and Einstein Radii
Sharon, K.; Gladders, M. D.; Bleem, L. E. +7 more
The core mass of galaxy clusters is both an important anchor of the radial mass distribution profile and a probe of structure formation. With thousands of strong lensing galaxy clusters being discovered by current and upcoming surveys, timely, efficient, and accurate core mass estimates are needed. We assess the results of two efficient methods to…
Two-Stage Evolution of an Extended C-Class Eruptive Flaring Activity from Sigmoid Active Region NOAA 12734: SDO and Udaipur-CALLISTO Observations
Monstein, Christian; Joshi, Bhuwan; Mitra, Prabir K. +4 more
In this article, we present a multi-wavelength investigation of a C-class flaring activity that occurred in the active region NOAA 12734 on 8 March 2019. The investigation utilizes data from the Atmospheric Imaging Assembly (AIA) and the Helioseismic Magnetic Imager (HMI) on board the Solar Dynamics Observatory (SDO) and the Udaipur-CALLISTO solar…
Searching for Extragalactic Exoplanetary Systems: The Curious Case of BD+20 2457
Limberg, Guilherme; Rossi, Silvia; Borbolato, Lais +4 more
Planets and their host stars carry a long-term memory of their origin in their chemical compositions. Thus, identifying planets formed in different environments improves our understating of planetary formation. Although restricted to detecting exoplanets within the solar vicinity, we might be able to detect planetary systems that formed in small e…