Search Publications
Theoretically Motivated Search and Detection of Non-thermal Pulsations from PSRs J1747-2958, J2021+3651, and J1826-1256
Rea, Nanda; Coti Zelati, Francesco; Torres, Diego F. +3 more
Based on a theoretical selection of pulsars as candidates for detection at X-ray energies, we present an analysis of archival X-ray observations performed with Chandra and XMM-Newton of PSR J1747-2958 (the pulsar in the “Mouse” nebula), PSR J2021+3651 (the pulsar in the “Dragonfly” nebula), and PSR J1826-1256. X-ray pulsations from PSR J1747-2958 …
On the Role of Ionospheric Ions in Sawtooth Events
Kistler, L. M.; Frey, H. U.; Lund, E. J. +2 more
Simulations have suggested that feedback of heavy ions originating in the ionosphere is an important mechanism for driving sawtooth injections. However, this feedback may only be necessary for events driven by coronal mass ejections (CMEs), whereas in events driven by streaming interaction regions (SIRs), solar wind variability may suffice to driv…
A modified CoRoT detrend algorithm and the discovery of a new planetary companion
Andrade, Laerte; Emilio, Marcelo; Janot-Pacheco, Eduardo +4 more
We present MCDA, a modification of the COnvection ROtation and planetary Transits (CoRoT) detrend algorithm (CDA) suitable to detrend chromatic light curves. By means of robust statistics and better handling of short-term variability, the implementation decreases the systematic light-curve variations and improves the detection of exoplanets when c…
Possible correlations between gamma-ray burst and its host galaxy offset
Liu, Yu; Wang, Fei-Fei; Zou, Yuan-Chuan +2 more
We collected the information of 304 gamma-ray bursts (GRBs) from the literature, and analyzed the correlations among the host galaxy offsets (the distance from the site of the GRB to the center of its host galaxy), T90,i (the duration T90 in rest-frame), TR45,i (the duration TR45 in rest-frame), Eγ,…
On the Radial Metallicity Gradient and Radial Migration Effect of the Galactic Disk
Zhao, Gang; Chen, Yuqin; Li, Chengdong +4 more
We study the radial metallicity gradient Δ[M/H]/ΔR g as a function of [Mg/Fe] and | Z| with the help of a guiding radius based on the Apache Point Observatory Galactic Evolution Experiment and Gaia and then analyze the radial migration effect on the radial metallicity gradient and metallicity-rotation gradient between the Galactic thi…
The VMC Survey. XXXII. Pre-main-sequence populations in the Large Magellanic Cloud
Sun, Ning-Chen; de Grijs, Richard; Marconi, Marcella +11 more
Context. Detailed studies of intermediate- and low-mass pre-main-sequence (PMS) stars outside the Galaxy have so far been conducted only for small targeted regions harbouring known star formation complexes. The VISTA Survey of the Magellanic Clouds (VMC) provides an opportunity to study PMS populations down to solar masses on a galaxy-wide scale. …
The transition region above sunspots
Tian, Hui; Zhang, Jingwen; Samanta, Tanmoy
Over decades, sunspots and their fine structures have been studied in detail at the photospheric level with different ground-based telescopes, as the surface of the Sun primarily emits light in the visible wavelengths. For a very long period, the upper atmosphere above the sunspot regions, especially the transition region (TR) above sunspots where…
Saturn's Planetary Period Oscillations During the Closest Approach of Cassini's Ring-Grazing Orbits
Dougherty, M. K.; Cowley, S. W. H.; Provan, G. +2 more
Saturn's planetary period oscillations (PPOs) are ubiquitous throughout its magnetosphere. We investigate the PPO's azimuthal magnetic field amplitude interior to the field-aligned currents, during the closest approaches of Cassini's ring-grazing orbits (October 2016 to April 2017), with periapses at 2.5 RS. The amplitudes of the northe…
Tripolar electric field Structure in guide field magnetic reconnection
Huang, Shiyong; Fu, Song; Ni, Binbin +2 more
It has been shown that the guide field substantially modifies the structure of the reconnection layer. For instance, the Hall magnetic and electric fields are distorted in guide field reconnection compared to reconnection without guide fields (i.e., anti-parallel reconnection). In this paper, we performed 2.5-D electromagnetic full particle simula…
A Study of the Hα Variability of Be Stars
Kjurkchieva, Diana P.; Dimitrov, Dinko P.; Ivanov, Emil I.
This paper presents the results of 4 years of high-resolution spectral observations of 69 emission-line stars, 54 of them being newly discovered sources. We classified the stars on the basis of their position in the two-color IR diagram and some additional criteria: shape and width of the Hα profile, presence of He lines, proper motion and paralla…