Search Publications
Oxygen Ion Butterfly Distributions Observed in a Magnetotail Dipolarizing Flux Bundle
Zhang, H.; Sun, W. J.; Fu, S. Y. +8 more
Cluster observed two intermittent oxygen ion (O+) flux enhancements with energy dispersions in a dipolarizing flux bundle, which is known as a region of enhanced northward magnetic field (Bz) embedded in the earthward high-speed flow. The flux enhancements of O+ show clear pitch angle dependences, which are termed …
DECam survey for low-mass stars and substellar objects in the UCL and LCC subgroups of the Sco-Cen OB Association (SCOCENSUS)
Mamajek, Eric E.; James, David J.; Bell, Cameron P. M. +5 more
Using images taken with the Dark Energy Camera (DECam), the first extensive survey of low mass and substellar objects is made in the ∼15-20 Myr Upper Centaurus Lupus (UCL) and Lower Centaurus Crux (LCC) subgroups of the Scorpius-Centaurus OB Association (Sco-Cen). Due to the size of our data set (>2Tb), we developed an extensive open source set…
Origin and Status of Low-Mass Candidate Hypervelocity Stars
Koo, Jae-Rim; Beers, Timothy C.; Lee, Young Sun +2 more
We present an analysis of the chemical abundances and kinematics of six low-mass dwarf stars, previously claimed to be candidate hypervelocity stars (HVSs). We obtained moderate-resolution (R=6000) spectra of these stars to estimate the abundances of several chemical elements (Mg, Si, Ca, Ti, Cr, Fe, and Ni), and derived their space velocities and…
OT UMa and GU leo: Two middle-contact w UMa binaries with similar stellar components
Michel, Raul; Kjurkchieva, Diana; Guerrero, Carlos
We present photometric observations of the W UMa binaries OT UMa and UG Leo. Our results from the light curve solutions are: (i) The two targets show partial eclipses; (ii) The components OT UMa and UG Leo are of G spectral type; (iii) Detailed q-search analysis was carried out for determination of the mass ratios; (iv) The two binaries are of W s…
Variable binaries and variables in binaries in the Binary star DataBase
Malkov, Oleg; Kovaleva, Dana; Kaygorodov, Pavel
The Binary star DataBase (BDB, http://bdb.inasan.ru) combines data from catalogs of binary and multiple stars of all observational types. There is a number of ways for variable stars to form or to be a part of binary or multiple systems. We describe how such stars are represented in the database.
Continuum emission enhancements and penumbral changes observed during flares by IRIS, ROSA, and Hinode
Fletcher, L.; Mathioudakis, M.; Guglielmino, S. L. +6 more
In this paper we describe observations acquired by satellite instruments ( Hinode/SOT and IRIS) and ground-based telescopes (ROSA@DST) during two consecutive C7.0 and X1.6 flares occurred in active region NOAA 12205 on 2014 November 7. The analysis of these data show the presence of continuum enhancements during the evolution of the events, observ…
X-Rays from e ± Pair Halos
Ruffolo, D.; Luangtip, W.; Eungwanichayapant, A. +1 more
It was previously suggested that e ± pair halos could be observed in γ-rays. Searching for pair halos is a challenging topic in γ-ray astronomy that has not yet yielded a convincing detection for an individual object. Here we propose that X-ray observations could reveal the existence of e ± pair halos. To support our suggesti…
The influence of Hinode/SOT NFI instrumental effects on the visibility of simulated prominence fine structures in Hα
Gunár, S.; Ichimoto, K.; Jurčák, J.
Context. Models of entire prominences with their numerous fine structures distributed within the prominence magnetic field use approximate radiative transfer techniques to visualize the simulated prominences. However, to accurately compare synthetic images of prominences obtained in this way with observations and to precisely analyze the visibilit…
Effect of Dust Storm and GCR Impact on the Production Rate of O3+ in MY 28 and MY 29: Modeling and SPICAM Observation
Haider, S. A.; Masoom, J.; Bougher, S. +1 more
We have developed a seasonally dependent energy loss model to calculate the zonally averaged production rates of O3+ due to impact of galactic cosmic rays in the dayside troposphere of Mars between solar longitudes (Ls) 0° and 360° at low latitudes (2°N, 2°S, 25°N, and 25°S), midlatitudes (45°N and 45°S), and high …
A robotic pipeline for fast GRB followup with the Las Cumbrés observatory network
Cucchiara, A.; Steele, I. A.; Marongiu, M. +9 more
In the era of multi-messenger astronomy the exploration of the early emission from transients is key for understanding the encoded physics. At the same time, current generation networks of fully-robotic telescopes provide new opportunities in terms of fast followup and sky coverage. This work describes our pipeline designed for robotic optical fol…