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Variations in 24-mu m morphologies among galaxies in the Spitzer Infrared Nearby Galaxies Survey: new insights into the Hubble sequence
ISM structure
2014/12/23
To study the distribution of star formation and dust emission within nearby galaxies, we measured five morphological parameters in the 3.6- and 24-μm wavebands for 65 galaxies in the Spitzer Infrared ...
We present a method for investigating variations in the upper end of the stellar initial mass function (IMF) by probing the production rate of ionizing photons in unresolved, compact star clusters wit...
THE "SWARM" MODEL FOR THE AZIMUTHAL BRIGHTNESS VARIATIONS IN SATURN'S RING A
Saturn's rings. Photometry observation ring system The image calibration
2014/12/10
A number of researchers have observed asymmetric azimuthal variations in Saturn's ring A not seen in any other portion of the rings. In order to explore this effect, photometric observations of the ri...
Future constraints on variations of the fine structure constant from combined CMB and weak lensing measurements
Future constraints variations fine structure constant combined CMB weak lensing measurements
2012/2/21
We forecast the ability of future CMB and galaxy lensing surveys to constrain variations of the fine structure constant. We found that lensing data, as those expected from satellite experiments as Euc...
Deriving the radial-velocity variations induced by stellar activity from high-precision photometry - Test on HD189733 with simultaneous MOST/SOPHIE data
late-type – stars: activity – stars: rotation – techniques: radial velocity – planetary systems – stars: individual
2011/10/19
Stellar activity induces apparent radial velocity (RV) variations in late-type main-sequence stars that may hamper the detection of low-mass planets and the measurement of their mass. We use simultane...
Searching for initial mass function variations in resolved stellar populations
Searching function variations resolved stellar populations
2011/10/13
The initial mass function (IMF) succinctly characterizes a stellar population, provides a statistical measure of the end result of the star-formation process, and informs our under- standing of the st...
Potential Biases in the Detection of Planetary Systems with Large Transit Timing Variations
methods: data analysis – planetary systems – planets and satellites: detection –techniques: photometric
2011/9/29
The Transit Timing Variations (TTVs) technique provides a powerful tool to detect additional planets in transiting exoplanetary systems. In this paper we show how transiting planets with significant T...
Revisiting the solar tachocline: Average properties and temporal variations
Revisiting solar tachocline:Average properties temporal variations
2011/9/28
The tachocline is believed to be the region where the solar dynamo operates. With over a solar cycle's worth of data available from the MDI and GONG instruments, we are in a position to investigate no...
Large Variations of the coefficient $J_2$ of geopotential, and the dynamical Love number $k_2^d$ from the analysis of laser ranging to LAGEOS~1 and LAGEOS~2
Earth’s satellites geopotential tides Love numbers
2011/8/24
Secular and seasonal variations of the coefficient $J_2$ of the geopotential are studied from the analysis of laser measurements of distances to the geodetic satellites LAGEOS~1 (1988--2003) and LAGEO...
Large Variations of the coefficient $J_2$ of geopotential, and the dynamical Love number $k_2^d$ from the analysis of laser ranging to LAGEOS~1 and LAGEOS~2
satellites geopotential tides Love numbers SLR ob- servations
2011/9/26
Secular and seasonal variations of the coefficient $J_2$ of the geopotential are studied from the analysis of laser measurements of distances to the geodetic satellites LAGEOS~1 (1988--2003) and LAGEO...
A Model for Thermal Phase Variations of Circular and Eccentric Exoplanets
methods data analysis planetary systems
2010/11/9
We present a semi-analytic model atmosphere for close-in exoplanets that captures the essential
physics of phase curves: orbital and viewing geometry, advection, and re-radiation. We calibrate the mo...
Search for Keplerian periods in light variations of T Tauri stars and Herbig Ae stars
Keplerian periods T Tauri stars Herbig Ae stars
2010/11/15
Long-term, uniform series of UBVR observations of T Tauri and Herbig Ae stars obtained
over 20 yr at the Maidanak Observatory as part of the ROTOR program are analyzed. We find
a linear relationship...
Quantifying the challenges of detecting unseen planetary companions with transit timing variations
celestial mechanics methods n-body simulations statistical stars planetary systems
2010/11/11
Both ground and space-based transit observatories are poised to signi cantly increase the number of known transiting planets and the number of precisely measured transit times.
Extreme Climate Variations from Milankovitch-like Eccentricity Oscillations in Extrasolar Planetary Systems
Earth and Planetary Astrophysics (astro-ph.EP)
2010/12/28
Although our solar system features predominantly circular orbits, the exoplanets discovered so far indicate that this is the exception rather than the rule.
Stellar Population Variations in the Milky Way's Stellar Halo
Cosmology and Extragalactic Astrophysics (astro-ph.CO) Galaxy Astrophysics (astro-ph.GA)
2010/12/29
If the stellar halos of disk galaxies are built up from the disruption of dwarf galaxies, models predict highly structured variations in the stellar populations within these halos.