Search Publications
The sunlit lunar atmosphere: A comprehensive study by CHACE on the Moon Impact Probe of Chandrayaan-1
Sridharan, R.; Ahmed, S. M.; Pratim Das, Tirtha +4 more
The altitudinal/latitudinal profile of the lunar atmospheric composition on the sunlit side was unraveled for the first time by the Chandra's Altitudinal Composition Explorer (CHACE) on the Moon Impact Probe, a standalone micro-satellite that impacted at the lunar south pole, as a part of the first Indian mission to Moon, Chandrayaan-1. Systematic…
Annealing a Follow-up Program: Improvement of the Dark Energy Figure of Merit for Optical Galaxy Cluster Surveys
Wu, Hao-Yi; Wechsler, Risa H.; Rozo, Eduardo
The precision of cosmological parameters derived from galaxy cluster surveys is limited by uncertainty in relating observable signals to cluster mass. We demonstrate that a small mass-calibration follow-up program can significantly reduce this uncertainty and improve parameter constraints, particularly when the follow-up targets are judiciously ch…
uvby-β photometry of solar twins . The solar colors, model atmospheres, and the Teff and metallicity scales
Casagrande, L.; Schuster, W. J.; Meléndez, J. +3 more
Aims: Solar colors have been determined on the uvby-β photometric system to test absolute solar fluxes, to examine colors predicted by model atmospheres as a function of stellar parameters (Teff, log g, [Fe/H]), and to probe zero-points of Teff and metallicity scales.
Methods: New uvby-β photometry is presented for …
Protons in the near-lunar wake observed by the Sub-keV Atom Reflection Analyzer on board Chandrayaan-1
Barabash, S.; Holmström, M.; Futaana, Y. +7 more
Significant proton fluxes were detected in the near-wake region of the Moon by an ion mass spectrometer on board Chandrayaan-1. The energy of these nightside protons is slightly higher than the energy of the solar wind protons. The protons are detected close to the lunar equatorial plane at a 140° solar zenith angle, that is, ∼50° behind the termi…
The Magnetic Field at the Inner Boundary of the Heliosphere Around Solar Minimum
Hoeksema, J. T.; Zhao, X. P.
STEREO A and B observations of the radial magnetic field between 1 January 2007 and 31 October 2008 show significant evidence that in the heliosphere, the ambient radial magnetic field component with any dynamic effects removed is uniformly distributed. Based on this monopolar nature of the ambient heliospheric field we find that the surface beyon…
C2D Spitzer-IRS spectra of disks around T Tauri stars. V. Spectral decomposition
Ménard, F.; Augereau, J. -C.; Grosso, N. +5 more
Context. Dust particles evolve in size and lattice structure in protoplanetary disks, due to coagulation, fragmentation and crystallization, and are radially and vertically mixed in disks due to turbulent diffusion and wind/radiation pressure forces.
Aims: This paper aims at determining the mineralogical composition and size distribution of t…
Short-Term Solar Flare Prediction Using Predictor Teams
Huang, Xin; Yu, Daren; Wang, Huaning +2 more
A short-term solar flare prediction model is built using predictor teams rather than an individual set of predictors. The information provided by the set of predictors could be redundant. So it is necessary to generate subsets of predictors which can keep the information constant. These subsets are called predictor teams. In the framework of rough…
Chandra localization and optical/near-infrared follow-up of Galactic X-ray sources
Miller-Jones, J. C. A.; Kuiper, L.; Torres, M. A. P. +3 more
We investigate a sample of 11 Galactic X-ray sources recently discovered with INTEGRAL or RXTE with the goal of identifying their optical and/or near-infrared (NIR) counterpart. For this purpose, new Chandra positions of nine objects are presented together with follow-up observations of all the targets in the optical and NIR. For the four sources …
Time Evolution of Coronal Magnetic Helicity in the Flaring Active Region NOAA 10930
Jing, Ju; Wang, Haimin; Chae, Jongchul +2 more
To study the three-dimensional (3D) magnetic field topology and its long-term evolution associated with the X3.4 flare of 2006 December 13, we investigate the coronal relative magnetic helicity in the flaring active region (AR) NOAA 10930 during the time period of December 8-14. The coronal helicity is calculated based on the 3D nonlinear force-fr…
Cluster-C1 observations on the geometrical structure of linear magnetic holes in the solar wind at 1 AU
Zhang, T. L.; Lucek, E.; Reme, H. +9 more
Interplanetary linear magnetic holes (LMHs) are structures in which the magnetic field magnitude decreases with little change in the field direction. They are a 10-30% subset of all interplanetary magnetic holes (MHs). Using magnetic field and plasma measurements obtained by Cluster-C1, we surveyed the LMHs in the solar wind at 1 AU. In total 567 …