Search Publications
Near-infrared polarimetric study of near-Earth object 252P/LINEAR: an implication of scattered light from the evolved dust particles
Kwon, Jungmi; Tamura, Motohide; Im, Myungshin +7 more
Context. Comets undergo resurfacing due to solar radiation, while their primordial interiors remain unchanged. Multi-epoch observations of comets enable us to characterize a change in sublimation pattern as a function of heliocentric distance, which in turn provides information on the dust environments of comets.
Aims: We aim to constrain the…
Approximation for attraction field of irregular celestial bodies using four massive points
Burov, Alexander A.; Guerman, Anna D.; Nikonova, Ekaterina A. +1 more
Approximation of the gravitational field of an irregular celestial body by the gravitational attraction field of four massive points is studied here in the framework of K-means method, known from the theory of pattern recognition. Using this approach, the simplified models for gravitational fields of asteroid (1620) Geographos and comet (67P) Chur…
Investigating the origin of the spectral line profiles of the Hot Wolf-Rayet Star WR 2
Crowther, P. A.; Wade, G. A.; Chené, A. -N. +12 more
The hot WN star WR 2 (HD 6327) has been claimed to have many singular characteristics. To explain its unusually rounded and relatively weak emission line profiles, it has been proposed that WR 2 is rotating close to break-up with a magnetically confined wind. Alternatively, the line profiles could be explained by the dilution of WR 2's spectrum by…
The Arches cluster revisited. III. An addendum to the stellar census
Najarro, F.; Clark, J. S.; Patrick, L. R. +1 more
The Arches is one of the youngest, densest and most massive clusters in the Galaxy. As such it provides a unique insight into the lifecycle of the most massive stars known and the formation and survival of such stellar aggregates in the extreme conditions of the Galactic Centre. In a previous study we presented an initial stellar census for the Ar…
Arbitrariness of potentials in interacting quintessence models
Bamba, Kazuharu; Roy, Nandan
Though we have entered an era of high precision cosmology the form of the quintessence potentials still remain arbitrary. In this work we explore the interacting quintessence models considering a parametrization of the quintessence potentials and tried to constrain the form of potentials using the recent cosmological observations. The particular p…
HD 96446: a long-period binary with a strongly magnetic He-rich primary with β Cephei pulsations
Järvinen, S.; González, J. F.; Butler, K. +14 more
Aims: HD 96446 is a magnetic B2p He-strong star that has been reported to be a β Cep pulsator. We present a detailed spectroscopic analysis of this object based on an intensive observational data set obtained in a multisite campaign with the spectrographs CORALIE, FEROS, and HARPS (La Silla); UVES (Paranal); HERCULES (Mt. John Observatory); a…
Extended star-forming regions within galaxies in a dense proto-cluster core at z = 2.53
Suzuki, Tomoko L.; Minowa, Yosuke; Koyama, Yusei +5 more
At z ∼ 2, star formation activity is thought to be high even in high-density environments such as galaxy clusters and proto-clusters. One of the critical but outstanding issues is if the structural growth of star-forming galaxies can differ depending on their surrounding environments. In order to investigate how galaxies grow their structures and …
Evidence of Hubble Flow-like Motion of Young Stellar Populations away from the Perseus Arm
Hernández, Jesús; Roman-Lopes, Alexandre; Tapia, Mauricio +2 more
In this Letter we present evidence of the coherent outward motion of a sample of young stars (t < 30 Myr) in the Perseus Arm, whose apparent origin is located in the vicinity of the W3/W4/W5 complex. Using astrometric and photometric data from the Gaia Data Release 2 catalog of an 8◦ radius field centered near W4, we selected a sampl…
A Search for Variable Stars in the Globular Cluster M4 with K2
Wallace, Joshua J.; Hartman, Joel D.; Bakos, Gáspár Á. +1 more
We extract light curves for 4554 objects with 9 < G < 19 in the K2 superstamp observations of the globular cluster M4, including 3784 cluster members, and search for variability. Among cluster-member objects, we detect 66 variables, of which 52 are new discoveries. Among objects not belonging to the cluster, we detect 24 variables, of which …
The 3D shape of Type IIb SN 2011hs
Spyromilio, J.; Wang, L.; Wheeler, J. C. +10 more
We observed seven epochs of spectropolarimetry in optical wavelengths for the Type IIb SN 2011hs, ranging from -3 to +40 d with respect to V-band maximum. A high degree of interstellar polarization was detected (up to ∼3 per cent), with a peak lying blueward of 4500 Å. Similar behaviours have been seen in some Type Ia supernovae (SNe), but had nev…