TAMASIS is an ASTRONET funded project aiming at enhancing the science that can be produced from the submillimeter surveys currently in preparation in Europe with instruments such as Herschel, Alma and SCUBA2.

We aim to provide reliable, easy-to-use, and optimal map-making tools for Herschel and future generation of sub-mm instruments, so that the ambitious science objectives that are set for these facilities can be met. In order to do this, we will have to combine the existing expertise on map-making problems with the much more specific instrumental expertise on the Herschel instruments. Indeed, most of the hurdles that will be encountered on the route to optimal map-making will not come from the algorithmic part of the map-making problem (a large body of research exists here), but from all the particular instrumental effects present in the PACS and SPIRE data.

Besides producing better map-making tools, an important objective that will significantly aid the interpretation of future sub-mm datasets is the possibility to directly compare these datasets to theoretical predictions. A fair model-data comparison requires the theoretical predictions to be in a form that is comparable to the observed maps, which is best achieved by generating observation-like mock maps from the theoretical models. Here, significant interaction between the modelers, the instrument experts and the data reduction experts is required for the mock maps to make sense. These mock maps can also be used to test how well any quantity derived from observed maps links to the physical properties one tries to measure or constrain.

The development of optimal map-making techniques requires that we design methods to assess their merits. These will require specific data analysis tools that again go well beyond what will be proposed to the Herschel user. Therefore our project will also develop along the way the specific data analysis tools requested for map-making performance assessments. These include source detection algorithms and statistical analysis tools, and more importantly tools that exploit the multi-wavelength nature of the Herschel data (i.e. PACS and SPIRE produce simultaneous imaging at 2, respectively 3 wavelengths, and they are in fact often operated in parallel, automatically generating a 5-wavelength cube of the field of view). De-convolution and source-detection are two areas where the ability to take in multi-wavelength data will make a significant difference.

TAMASIS is a collaboration between french, dutch and austrian institutes: CEA/SAp and IAS in France, Leiden Observatory in the Netherlands, and European Southern observatory in Germany, with support from the FWF, the Austrian Science Fund.

The CEA team has been responsible for the complete development, characterization and calibration of the bolometer array camera of the PACS instrument. Therefore it is in this team that the most accurate knowledge on the particulars of this new breed of detectors can be found. It is clear that optimal data processing will require including this knowledge at the heart of the algorithms. It is also at CEA that the PACS instrument simulator was developed and this expertise will be heavily requested during the algorithm-testing part of the project. The CEA team has also a strong signal processing lab that will serve as consultant during the algorithmic development phase. Finally, through its large involvement in the PACS and SPIRE science programs, the CEA team will provide numerous case studies on which to perform the evaluation of the map-making methods' performances. The contact point for the CEA site is Marc Sauvage.

The IAS team has a long-standing experience for developing software dedicated to the extraction of the extended emission from long-wavelength data (ISO, IRAS, Spitzer, PRONAOS). A collaboration has also been engaged with the Laboratoire des Signaux et Systèmes (L2S, Supelec, Orsay) for the development of new pipelines using Bayesian methods. The L2S team will serve as consultant during our project. The IAS team has a strong expertise for SPIRE and Planck galactic and cosmological simulations. The team is also in charge of the SPIRE/Planck cross-calibration issue. The IAS team is also our agreed interface with B. Sibthorpe (UK ATC), the author of the SPIRE instrument simulator. The contact point for the IAS site is Alain Abergel.

The ESO team has extensive experience in modeling the sub-mm galaxy population, with specific contributions to various sub-mm projects over the last five years. Prediction made by the Innsbruck team have help significantly to define survey parameters and help assess feasibility of particular projects like SHADES and Herschel ATLAS. Currently the main aim of the team is to produce the best possible mocks for the upcoming surveys, taking into account survey design and mapping strategies. Furthermore, the team is updating or designing techniques to find specific structures like clusters of galaxies in these surveys, testing these techniques on mocks. The contact point for ESO is Eelco van Kampen.

The Leiden team has many years of expertise in surveys at infrared and submillimetre wavelengths with ISO and SCUBA, but also at other wavelengths (radio, near-IR, optical). In this context, the Leiden has already developed a number of prototypes for the software tools to be delivered. Most of these were developed in the context of submillimetre surveys with SCUBA, such as source detection and reliability analysis tools. These surveys will be taken to the next level with Herschel, and with the SCUBA-2 Cosmology Legacy Survey, of which Paul Van der Werf, the Leiden contact point, is one of the Principal Investigators.

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Contact points


Marc SauvageCEA/DSM/Irfu/Service d'Astrophysique
 CE Saclay
 91191 Gif sur Yvette CEDEX, France
 

Alain AbergelIAS, Centre universitaire d'Orsay
 Bât. 120-121
 91405 Orsay CEDEX, France
 

Eelco van KampemESO
 Karl-Schwarzschild-Str. 2
 D-85748 Garching bei München
 

Paul van der WerfLeiden Observatory
 P.O. Box 9513
 NL - 2300 RA Leiden
 

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Job offers

The following announcement has been submitted to the AAS Job Register and will appear in the December issue. The closing date for application has been set at January 31st, 2009.

CEA-Saclay, IAS-Orsay, Leiden Observatory and Innsbruck University invite applications for 4 postdoctoral positions in the framework of the TAMASIS project. TAMASIS is an Astronet-funded project dedicated to provide innovative tools for simulating, reconstructing and analyzing sub-millimeter mapping observations, with Herschel and Alma science as the primary drivers. The project is divided in three sites: Innsbruck, offering one 3-year position to produce realistic sky simulations to serve as controlled input, CEA-Saclay and IAS-Orsay where two 2-year positions will develop map-making tools using simulations and real data from the local Herschel key projects, and Leiden Observatory offering a 3-year position to work on advanced survey analysis tools exploiting the multi-wavelength capabilities of instruments such as SPIRE and PACS on Herschel.

The successful candidates are expected to dedicate 70% of their time to the TAMASIS project, with the remaining 30% used on personal science projects. This division of time is flexible depending on the overlap between the candidates' science projects and the TAMASIS science cases.

The interested applicants should have a PhD in astronomy or signal processing. Expertise in far-infrared and/or sub-millimeter science is highly desirable. Applications should include a curriculum vitae, a description of past science accomplishments and if applicable a summary of the proposed personal research program. Applicants should arrange for 3 letters of reference to be sent directly to TAMASIS. Applications can be sent to the PI institute (CEA-Saclay), or to the preferred TAMASIS site.

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