Search Publications
Missions
Journals
Publication Years
TOPCAT and Gaia
Taylor, M. B.
TOPCAT, and its command line counterpart STILTS, are powerful tools for working with large source catalogs. ESA's Gaia mission, most recently with its second data release, is producing source catalogs of unprecedented quality for more than a billion sources. This paper presents some examples of how TOPCAT and STILTS can be used for analysis of Gai…
Study of Sunspot Penumbra to Umbra Area Ratio Using Kodaikanal White-light Digitised Data
Banerjee, Dipankar; Jha, Bibhuti Kumar; Mandal, Sudip
We study the long-term behaviour of the sunspot penumbra to umbra area ratio by analysing recently digitised Kodaikanal white-light data (1923 - 2011). We implement an automatic umbra extraction method and compute the ratio over eight solar cycles (Cycles 16 - 23). Although the average ratio does not show any variation with spot latitudes, cycle p…
IMF By Influence on Magnetospheric Convection in Earth's Magnetotail Plasma Sheet
Hamrin, M.; Tenfjord, P.; Laundal, K. M. +7 more
We use Geotail, Cluster, and Time History of Events and Macroscale Interactions during Substorms data over 15 years (1995-2009) to statistically investigate convective ion flows (V⊥xy<200 km/s) in the magnetotail plasma sheet under the influence of a clearly nonzero dawn-dusk interplanetary magnetic field (IMF By). We find…
A nitrogen-enhanced metal-poor star discovered in the globular cluster ESO280-SC06
Martell, Sarah L.; Simpson, Jeffrey D.
We report the discovery of the only very nitrogen-enhanced metal-poor star known in a Galactic globular cluster. This star, in the very metal-poor cluster ESO280-SC06 , has [N/Fe] > +2.5, while the other stars in the cluster show no obvious enhancement in nitrogen. Around 80 NEMP stars are known in the field, and their abundance patterns are be…
Recent Advancements and Remaining Challenges Associated With Inner Magnetosphere Cross-Energy/Population Interactions (IMCEPI)
Jordanova, Vania K.; Yu, Yiqun; Liemohn, Mike W. +2 more
The geospace inner magnetosphere, within about 10 Earth radii, contains various plasma populations with energy from a few electron volts to megaelectron volts and plays important roles in regulating the energy density of the magnetosphere, the magnetic field configuration, and wave dynamics. As an integrated part of the magnetosphere, the inner ma…
Discovery of a transient ultraluminous X-ray source in the elliptical galaxy M86
Kundu, Arunav; Zepf, Stephen E.; Maccarone, Thomas J. +2 more
We report the discovery of the transient ultraluminous X-ray source (ULX) CXOU J122602.3+125951 (hereafter M86 tULX-1), located 3'52″ (19 kpc) north-west of the centre of the giant elliptical galaxy M86 (NGC 4406) in the Virgo Cluster. The spectrum of M86 tULX-1 can be fit by a power law plus multicolour disc model with a 1.0^{+0.8}_{-2.6} index a…
Kinematics of Open Star Clusters Based on the Data of the New Version of the "Homogeneous Catalog of Open Cluster Parameters"
Loktin, A. V.; Popova, M. E.
We investigate some aspects of Galactic disc kinematics based on the data on open clusters from the current version of "The Homogeneous Catalog of the Main Parameters of Open Star Clusters" and from Gaia DR2. Based on the radial velocity and proper motion data for the clusters we determine the angular velocity of the Sun in the Galaxy as Ω0
The Trans-Neptunian Object (84922) 2003 VS2 through Stellar Occultations
Bérard, D.; Brosch, N.; Maury, A. +50 more
We present results from three world-wide campaigns that resulted in the detections of two single-chord and one multi-chord stellar occultations by the plutino object (84922) 2003 VS2. From the single-chord occultations in 2013 and 2014 we obtained accurate astrometric positions for the object, while from the multi-chord occultation on 2…
A Catalog of Galaxies in the Direction of the Perseus Cluster
Wittmann, Carolin; Kotulla, Ralf; Lisker, Thorsten +4 more
We present a catalog of 5437 morphologically classified sources in the direction of the Perseus galaxy cluster core, among them 496 early-type low-mass galaxy candidates. The catalog is primarily based on V-band imaging data acquired with the William Herschel Telescope, which we used to conduct automated source detection and derive photometry. We …
A Near-infrared View of Nearby Galaxies: The Case of NGC 6300
Díaz, R. J.; Agüero, M. P.; Gaspar, G. +3 more
We present a near-infrared study of the Seyfert 2 galaxy NGC 6300, based on subarcsecond images and long slit spectroscopy obtained with Flamingos-2 at Gemini South. We have found that the peak of the nuclear continuum emission in the K s band and the surrounding nuclear disk are 25 pc off-center with respect to the center of symmetry…