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Four Fundamental Foreground Power Spectrum Shapes for 21 cm Cosmology Observations
Four Fundamental Foreground Power Spectrum Shapes Cosmology Observations
2012/2/24
Contamination from instrumental effects interacting with bright astrophysical sources is the primary impediment to measuring Epoch of Reionization and BAO 21 cm power spectra-an effect called mode-mix...
TNOs are Cool: A survey of the trans-Neptunian region V. Physical characterization of 18 Plutinos using Herschel PACS observations
Kuiper belt objects Plutinos planetary systems observational photometric
2012/2/23
We present Herschel PACS photometry of 18 Plutinos and determine sizes and albedos for these objects using thermal modeling. We analyze our results for correlations, draw conclusions on the Plutino si...
Using Kepler transit observations to measure stellar spot belt migration rates
Activity Spots Planetary Systems Planet Satellites Sunspots
2012/2/23
Planetary transits provide a unique opportunity to investigate the surface distributions of star spots. Our aim is to determine if, with continuous observation (such as the data that will be provided ...
Precision simulation of ground-based lensing data using observations from space
methods: data analysis – techniques: image processing – gravitational lensing: weak – galaxies: structure
2011/10/13
Current and upcoming wide-field, ground-based, broad-band imaging surveys promise to address a wide range of outstanding problems in galaxy formation and cosmology. Several such uses of ground-based d...
Graviton mass bounds from space-based gravitational-wave observations of massive black hole populations
Graviton mass bounds space-based gravitational-wave observations massive black hole populations
2011/10/17
Space-based gravitational-wave detectors, such as LISA or a similar ESA-led mission, will offer unique opportunities to test general relativity. We study the bounds that space-based detectors could pl...
Do Fermi-LAT observations really imply very large Lorentz factors in GRB outflows ?
gamma-ray burst: general gamma-ray burst: individual: GRB 080916C radiative transfer radiation mechanisms: non-thermal
2011/10/20
Recent detections of GeV photons in a few GRBs by Fermi-LAT imply huge bulk Lorentz factors to avoid a large gamma gamma optical depth at high energy. Estimates can be as high as Gamma ~ 1000 in the m...
Observations of Mg II Absorption Near z ~ 1 Galaxies Selected From The DEEP2 Redshift Survey
Observations Absorption Galaxies Selected Redshift Survey
2011/10/13
We study the frequency of Mg II absorption in the outer haloes of galaxies at z = 0.6 - 1.4 (with median z = 0.87), using new spectra obtained of ten background quasars with galaxy impact parameters o...
Radio continuum observations of new radio halos and relics from the NVSS and WENSS surveys
Radio Continuum: galaxies – Galaxies: Clusters: general, intracluster medium – Cosmology: large-scale structure of Universe
2011/10/20
Radio halos and relics are diffuse radio sources found in galaxy clusters showing significant substructure at X-ray wavelengths. These sources provide important information about non-thermal processes...
Measuring a cosmological distance-redshift relationship using only gravitational wave observations of binary neutron star coalescences
neutron stars gravitational waves cosmology
2011/10/14
Detection of gravitational waves from the inspiral phase of binary neutron star coalescence will allow us to measure the effects of the tidal coupling in such systems. These effects will be measurable...
Blazars as Ultra-High-Energy Cosmic-Ray Sources: Implications for TeV Gamma-Ray Observations
Ultra-High-Energy Cosmic-Ray Sources Implications TeV Gamma-Ray Observations
2011/10/20
Spectral fitting of correlated multiwavelength data of BL Lac objects and Fanaroff-Riley I radio galaxies gives the mean comoving magnetic field strength B', the bulk outflow Doppler factor Gamma, and...
Multi-wavelength observations of the young binary system Haro 6-10: The case of misaligned discs
Binary stars - Star Formation - Haro 6-10
2011/10/17
Context. We present a multi-wavelength, high-resolution observational survey of the young binary system Haro 6-10 (GV Tau, IRAS 04263+2426), which is harbouring one of the few known infrared companion...
X-ray Observations of Radio Transients without Optical Hosts
X-ray Observations Radio Transients without Optical Hosts
2011/10/19
We present a 50 ks Chandra ACIS-I X-ray observation of the Bower et al. VLA archival field. The observations reach a limiting sensitivity of ~1E-4 counts/s, corresponding to a flux of a few times 1E-1...
The mass function of black holes at 1rison of models with observations
mass function black holes comparison models observations
2011/10/19
In this paper, we compare the observationally derived black hole mass function (BHMF) of luminous broad-line quasars (BLQSOs) at 1rawn from the Sloan Digital Sky Survey (SDSS) presented in Kel...
Observations of the December 13 and 14, 2006, Solar Particle Events in the 80 MeV/n - 3 GeV/n range from space with PAMELA detector
Observations Solar Particle Events detector
2011/10/13
We present the space spectrometer PAMELA observations of proton and helium fluxes during the December 13 and 14, 2006 solar particle events. This is the first direct measurement of the solar energetic...
PSR J0007+7303 in the CTA1 SNR: New Gamma-ray Results from Two Years of Fermi-LAT Observations
CTA1 SNR:Gamma-ray Results Fermi-LAT Observations
2011/10/12
One of the main results of the Fermi Gamma-Ray Space Telescope is the discovery of {\gamma}-ray selected pulsars. The high magnetic field pulsar, PSR J0007+7303 in CTA1, was the first ever to be disco...