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Atmospheric parameter retrievals over land from AMSU measurements, such as atmospheric temperature and moisture profiles, could be possible using a reliable estimate of the land emissivity. The land surface emissivities have been calculated using 6 months of data, for 30 beam positions (observation zenith angles from –58° to +58°) and the 23.8, 31.4, 50.3,(More)
—To retrieve temperature and humidity profiles from special sensor microwave/temperature (SSM/T) and advanced microwave sounding units (AMSU), it is important to quantify the contribution of the Earth surface emission. So far, no global estimates of the land surface emissivities are available at SSM/T and AMSU frequencies and scanning conditions. The land(More)
We have developed a niobium titanium nitride (NbTiN) based superconductor-insulator-superconductor (SIS) receiver to cover the 350 micron atmospheric window. This frequency band lies entirely above the energy gap of niobium (700 GHz), a commonly used SIS superconductor. The instrument uses an open structure twin-slot SIS mixer that consists of two(More)
The abundance ratio of consecutive members of the cyanopolyynes family has been explored in CRL618 using data acquired in a complete line survey covering the frequency range 81-356 GHz. The J up range explored for the different molecules is the following: 1 to 4 for HCN and HNC, 9 to 39 for HC 3 N, 31 to 133 for HC 5 N, and 72 to 85 for HC 7 N (not detected(More)
[1] We study the potential of millimeter and sub-millimeter wavelengths for precipitation retrieval from geostationary sensors based on mesoscale cloud modeling and radiative transfer computation. Hydrometeor profiles simulated with the Meso-NH cloud resolving model for five European midlatitude situations are used to compute the brightness temperatures at(More)
We present accurately calibrated submillimeter atmospheric transmission spectra obtained with a Fourier-transform spectrometer at the Caltech Submillimeter Observatory on Mauna Kea, Hawaii. These measurements cover the 0.9-0.3-mm wavelength range and are the first in a series aimed at defining the terrestrial long-wave atmospheric transmission curve. The(More)
We present observations of the 5 1,5 →4 2,2 transition of water vapor at 325.15 GHz taken with the CSO telescope towards Orion IRc2. The emission is more extended than that of other molecular species such as CH 3 OH. However, it is much less extended than the emission of water vapor at 183.31 GHz reported by Cernicharo et al (1994). A comparison of the line(More)
Using a balloon-borne 60 cm telescope equipped with an SIS receiver we have searched for the 425 GHz molecular oxygen line in the NGC7538 and the W51 regions. The experiment was technically successful (confirmed by the detection of the 13 CO (4–3) line at 440 GHz), but we failed to detect emission from molecular oxygen. The inferred upper limits of the O 2(More)
The success of any ALMA phase-calibration strategy, which incorporates phase transfer , depends on a good understanding of how the atmospheric path delay changes with frequency (e.g. Holdaway & Pardo 2001). We explore how the wet dispersive path delay varies for realistic atmospheric conditions at the ALMA site using the ATM transmission code. We find the(More)