Search Publications
Relative pointing offset analysis of calibration targets with repeated observations with Herschel-SPIRE Fourier-transform spectrometer
Valtchanov, Ivan; Hopwood, Rosalind; Lu, Nanyao +9 more
We present a method to derive the relative pointing offsets for SPIRE Fourier-Transform Spectrometer (FTS) solar system object (SSO) calibration targets, which were observed regularly throughout the Herschel mission. We construct ratios R obs( ν) of the spectra for all observations of a given source with respect to a reference. The refe…
The effect of sideband ratio on line intensity for Herschel/HIFI
Braine, Jonathan; Ossenkopf, Volker; Higgins, Ronan +8 more
The Heterodyne Instrument for the Far Infrared (HIFI) on board the Herschel Space Observatory is composed of a set of fourteen double sideband mixers. We discuss the general problem of the sideband ratio (SBR) determination and the impact of an imbalanced sideband ratio on the line calibration in double sideband heterodyne receivers. The HIFI SBR …
PACS photometer calibration block analysis
Balog, Z.; Marton, G.; Müller, T. G. +3 more
The absolute stability of the PACS bolometer response over the entire mission lifetime without applying any corrections is about 0.5 % (standard deviation) or about 8 % peak-to-peak. This fantastic stability allows us to calibrate all scientific measurements by a fixed and time-independent response file, without using any information from the PACS…
Herschel SPIRE FTS spectral mapping calibration
Valtchanov, Ivan; Hopwood, Rosalind; Lu, Nanyao +12 more
The Herschel SPIRE Fourier transform spectrometer (FTS) performs spectral imaging in the 447-1546 GHz band. It can observe in three spatial sampling modes: sparse mode, with a single pointing on sky, or intermediate or full modes with 1 and 1/2 beam spacing, respectively. In this paper, we investigate the uncertainty and repeatability for fully sa…
Operations and performance of the PACS instrument 3He sorption cooler on board of the Herschel space observatory
Poglitsch, A.; Okumura, K.; Sauvage, M. +5 more
A 3He sorption cooler produced the operational temperature of 285 mK for the bolometer arrays of the Photodetector Array Camera and Spectrometer (PACS) instrument of the Herschel Space Observatory. This cooler provided a stable hold time between 60 and 73 h, depending on the operational conditions of the instrument. The respective hold …
First results with the boloSource() algorithm: photometry of faint standard stars observed by Herschel/PACS
Marton, G.; Müller, T. G.; Kiss, C. +1 more
The boloSource() algorithm is a tool to separate the signal of compact sources from that of the diffuse background in the timeline of far-infrared measurements performed by the PACS camera of the Herschel Space Observatory. An important characteristic and quality indicator of this method is that how well it can reproduce the flux of faint standard…
Herschel out-of-field stray-light characterization
Altieri, B.; Sanchez-Portal, M.; Pilbratt, G. L. +5 more
Out-of-field stray-light spots of the Herschel telescope optics relative to the PACS and SPIRE instrument apertures were modeled by ray tracing simulations with the Advanced Systems Analysis Program (ASAP, by Breault Research Organization) prior to launch. The predicted stray-light behaviour was verified by dedicated stray-light calibration observ…
In-flight calibration of the HIFI diplexers
Mueller, Michael; Teyssier, David; Delforge, Bertrand +4 more
HIFI is a heterodyne spectrometer aboard the Herschel Space Observatory, providing high-spectral-resolution capabilities. Of its seven frequency bands, four (bands 3, 4, 6, and 7) employ Martin-Puplett diplexers to combine sky signal and local oscillator at the two linear polarizations H and V, prior to feeding them into the mixers (receivers). Th…
Publisher's Erratum to: The Herschel PACS photometer calibration. A time dependent flux calibration for the PACS chopped point-source photometry AOT mode
Sauvage, Marc; Okumura, Koryo; Linz, Hendrik +7 more
The Herschel PACS photometer calibration. A time dependent flux calibration for the PACS chopped point-source photometry AOT mode
Sauvage, Marc; Okumura, Koryo; Linz, Hendrik +7 more
We present a flux calibration scheme for the PACS chopped point-source photometry observing mode based on the photometry of five stellar standard sources. This mode was used for science observations only early in the mission. Later, it was only used for pointing and flux calibration measurements. Its calibration turns this type of observation into…