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Study of magnetic field geometry and extinction in Bok globule CB130
Das, H. S.; Chakraborty, A.
We trace the peripheral magnetic field structure of Bok globule CB130 by estimating the linear polarization of its field stars in the R band. The magnetic field orientation sampled by these stars, aligned on average among themselves, and the polarization produced within the cloud has a different direction from that of Galactic plane with an offset…
A Perturbative Analysis of Synchrotron Spectral Index Variation over the Microwave Sky
Aluri, Pavan K.; Saha, Rajib
In this paper, we implement a perturbative approach, first proposed by Bouchet & Gispert, to estimate the variation of the spectral index of galactic polarized synchrotron emission, using a linear combination of simulated Stokes Q polarization maps of selected frequency bands from WMAP and Planck observations on a region of sky dominated by th…
Morphological classification of local luminous infrared galaxies
Le Floc'h, E.; Armus, L.; Charmandaris, V. +6 more
We present analysis of the morphological classification of 89 luminous infrared galaxies (LIRGs) from the Great Observatories All-sky LIRG Survey (GOALS) sample, using non-parametric coefficients and compare their morphology as a function of wavelength. We rely on images that were obtained in the optical (B- and I-band) as well as in the infrared …
Isolating the Young Stellar Population in the Outer Disk of NGC 300
Dolphin, Andrew E.; Skillman, Evan D.; Williams, Benjamin F. +2 more
The recent star formation history (SFH) in the outer disk of NGC 300 is presented through the analysis of color-magnitude diagrams (CMDs). We analyze resolved stellar photometry by creating CMDs from four Hubble Space Telescope fields containing a combination of images from the Advanced Camera for Surveys and the UVIS imager aboard the Wide Field …
The particle carriers of field-aligned currents in the Earth's magnetotail during a substorm
Dandouras, I.; Kistler, L. M.; Dunlop, M. +4 more
Although the particle carriers of field-aligned currents (FACs) in the Earth's magnetotail play an important role in the transfer of momentum and energy between the solar wind, magnetosphere, and ionosphere, the characteristics of the FAC carriers have been poorly understood. Taking advantage of multiinstrument magnetic field and plasma data colle…
Weak, Quiet Magnetic Fields Seen in the Venus Atmosphere
Luhmann, J. G.; Russell, C. T.; Zhang, T. L. +2 more
The existence of a strong internal magnetic field allows probing of the interior through both long term changes of and short period fluctuations in that magnetic field. Venus, while Earth’s twin in many ways, lacks such a strong intrinsic magnetic field, but perhaps short period fluctuations can still be used to probe the electrical conductivity o…
Evolutionary status of isolated B[e] stars
Liu, Sheng-Yuan; Chen, Wen-Ping; Lee, Chien-De
Aims: We study a sample of eight B[e] stars with uncertain evolutionary status to shed light on the origin of their circumstellar dust.
Methods: We performed a diagnostic analysis on the spectral energy distribution beyond infrared wavelengths, and conducted a census of neighboring region of each target to ascertain its evolutionary stat…
Suprathermal electron penetration into the inner magnetosphere of Saturn
Lewis, G. R.; Coates, A. J.; Thomsen, M. F. +3 more
For most Cassini passes through the inner magnetosphere of Saturn, the hot electron population (> few hundred eVs) largely disappears inside of some cutoff L shell. Anode-and-actuation-angle averages of hot electron fluxes observed by the Cassini Electron Spectrometer are binned into 0.1 Rs bins in dipole L to explore the properties …
Dark matter fraction of low-mass cluster members probed by galaxy-scale strong lensing
Grillo, C.; Balestra, I.; Rosati, P. +8 more
We present a strong lensing system, composed of four multiple images of a source at z = 2.387, created by two lens galaxies, G1 and G2, belonging to the galaxy cluster MACS J1115.9+0129 at z = 0.353. We use observations taken as part of the Cluster Lensing and Supernova survey with Hubble, and its spectroscopic follow-up programme at the Very Larg…
Planning and implementation of the on-comet operations of the instrument SD2 onboard the lander Philae of Rosetta mission
Mottola, S.; Remetean, E.; Dolives, B. +4 more
The lander Philae of the Rosetta mission landed on the surface of the comet 67 P/Churyumov-Gerasimenko on November 12, 2014. Among the specific subsystems and instruments carried on Philae, the sampling, drilling and distribution (SD2) subsystem had the role of providing in-situ operations devoted to soil drilling, sample collection, and their dis…