Intensity Interferometry in Astronomy

Intensity Working Group of the IAU Commission 54 on Optical/Infrared Interferometry

First call for establishment of the work group and preliminary mandate:

From: Guy Perrin <guy.perrin@obspm.fr>
Subject: Creation of a working group on intensity interferometry
Date: Fri, 18 Apr 2008 19:01:08 +0200
To: olbin@obs.ujf-grenoble.fr

Dear Olbiners,

We call for expression of interest to participate to a working group on intensity interferometry in the IAU Commission on optical infrared interferometry # 54.

Intensity interferometry was successfully introduced by Robert Hanbury Brown and colleagues in the 60s-70s. It was used to measure the diameter of bright stars and the orbit of binaries and was the first to measure the limb-darkening of a star. The intensity correlation technique has some advantages with respect to its amplitude equivalent but has the drawback to require a large number of photons hence a stronger limitation in sensitivity. However, recent developments of detectors and electronics have increased the band pass of detectors and consequently the potential sensitivity of intensity interferometry. Also, various gamma ray detection observatories, based on collection of Cerenkov radiation produced in the atmosphere, are potentially making available large collecting area mirrors.

We believe that it is therefore important to the interferometry community to understand the interest and potential of the technique in the light of these new developments. We propose to create a working group with this preliminary mandate. As a first goal, we would propose preparation of a white paper for the purpose of briefing our commission and community. Creation of the working group will be decided upon reception of expressions of interest.

Guy Perrin and Steve Ridgway for the Commission.

As a result of this call, a first version of white paper was drafted: Revival of Intensity Interferometry. Here is the next working version of the white paper. Suggestions for improvement are most welcome.

A list of astrophysical objects, which are difficult or impossible to observe without intensity interferometry, was submitted to the Decadal Survey committee in February 2009.

We have prepared of list of references, historical and new, which describes the past and current development of (mainly astronomical) intensity interferometry.

Two meetings were already held:

June 2008: first meeting in Marseilles

January 2009: workshop in Salt Lake City

Maintenance: Erez Ribak, accessible at eribak ҩ physics.technion.ac.il.