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Last NEWS 17/09/2009 - First Light Survey

First light survey

Here find a preview of the excellent results of the First Light Survey

Official ESA Press release

ESA Planck portal

Planck Science Team Webpage

What is Planck

The Planck satellite of the European Space Agency has been launched on May 14, 2009, and is now operating from the Lagrangian point L2 of the sun-earth system. The satellite is devoted to the measurement of the Cosmic Microwave Background anisotropy and polarization, with unprecedented sensitivity and angular resolution. The Low Frequency Instrument (LFI) is described here.

The High Frequency Instrument (HFI) covers the spectral range 80-1000 GHz in 6 bands. This range includes the peak of emission of the CMB, the emission of diffuse interstellar dust, the negative, positive and null Sunyaev-Zeldovich effect of the CMB in the direction of clusters of Galaxies. Covering high frequencies, HFI features high angular resolution (ranging from 10 to 5 arcminutes) and can explore the power spectrum of CMB anisotropy and polarization up to multipoles of the order of 2500. HFI has been developed based on the experiences acquired with the stratospheric balloon missions BOOMERanG and Archeops, and uses cryogenic bolometers as detectors, cooled at 0.1K by means of a newly devloped dilution refrigerator. The instrument uses both spider-web and polarization-sensitive bolometers, whose sensitivity is limited only by the radiative background.

Planck will produce "definitive" maps of the microwave sky, observing all the details of the radiation coming from the primeval fireball. This is the hot opaque initial phase of the evolution of the universe, started about 14 billion years ago, and lasting for the first 400000 years. Analyzig the polarization properties of the CMB it will be possible to learn more about the hypotetic process of cosmic inflation, happening a split-second after the Big Bang.

Our contribution to Planck

The G31 group has contributed to the High Frequency Instrument on Planck providing:

1) a key hardware component: the cryogenic preamplifiers for all the detectors. These units process the very low level (nV) high impedance (MOhm) signal from the bolometers, as close as possible to the source of the signal, and convert it in a low-impedance signal to avoid electromangetic interference. In order to be mounted close to the detectors, these units operate on the 50K stage of the satellite, with a very low power dissipation (less than 200 mW for 72 differential channels). The units have been designed and prototipized at the physics Department (link a paper Brienza). The qualification and flight models have been built in collaboration with Galileo Avionica.

Picture of one of the 12 cryogenic preamplifiers modules box modules.

Picture of the complete system mounted on the satellite.

2) support in the definition of the instrument, of the measurement and calibration strategy, and in the definition of various phases of the data analysis.

Laboratory calibration of HFI.

Five members of the group (Paolo de Bernardis (Co-Investigator), Silvia Masi, Alessandro Melchiorri, Francesco Piacentini, Gianluca Polenta) are members of the core team of Planck. In addition, F. Nati is an associate member of the Planck collaboration.

After the successfull launch on May 14th, 2009, Planck is working nominally in L2, at 1.5 million km from the earth. In the second half of August Planck has carried out a first light survey, with excellent results.

Launch event 14/05/2009

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