2014: An Exciting Year for CTA
17 April 2018
The Cherenkov Telescope Array (CTA) is the planned next generation ground-based very-high-energy gamma ray observatory; an open infrastructure, it will serve a wide particle astrophysics community for many years to come. The CTA will be composed of two arrays, one in the northern hemisphere and one in the south, and aims to push the sensitivity to gamma-ray fluxes down by more than an order of magnitude compared to current instruments. In addition, by using a combination of different-sized telescopes (large (LST), medium (MST) and small (SST) size telescopes), a wide energy range, from about 20 GeV to about 300 TeV, will be covered. Finally, the use of many telescopes will provide unprecedented angular resolution. In the baseline design, the CTA southern array, which will be larger in order to take advantage of its favorable exposure to the Galactic plane, will be composed of up to 70 SSTs, 25 MSTs and 4 LSTs. The northern array will concentrate on extragalactic objects and is not expected to contain SSTs.
2014 will be a crucial one for the CTA Collaboration
The first piece of news is the change of the Project Manager. After 3 years of dedicated work for CTA, John Carr stepped down at the end of 2013. A new Project Manager, Christopher Townsley, has now been appointed. Christopher earned his PhD in Physics in 2003 and since then has worked as project manager for big commercial projects, such as the London Railway Network, and for science projects such as FAIR, the Facility for Antiproton and Ion Research. Christopher was welcomed to CTA by the Project Committee in January, and started his new adventure in CTA. Let’s wish him good luck for his new challenge in this fascinating project, and John all the best for the future.
This year’s real cornerstone will be choice of the site; this will make it possible to start the project substantively.. After years of study of the site characteristics and of simulation of the array, a site ranking , endorsed by the Project Committee and the Collaboration Board, has been proposed to the Resource Board. CTA is now in the next phase, in which negotiation with the host countries has started, and a study of the relative costs of the different options is on-going. All of CTA’s work packages will soon know for which particular site simulations and hardware will have to be fine-tuned and finalized.
Another achievement expected this year is the completion of many telescope prototypes. One MST and three SST designs, one employing a single mirror (SST-1M) and two using a dual-mirror design (SST-2M), will be completed. Prototypes of the MST and the SST-1M structures have already been deployed in Berlin (Fig. 1.a) and Krakow (Fig1.b) respectively, and in the second half of 2014 the ASTRI SST-2M prototype will be deployed on Mount Etna in Italy and the SST-GATE dual-mirror telescope will be deployed in Paris. Prototypes of the different camera solutions, using both the traditional photomultiplier tubes and newer silicon-based detectors, will be tested on the telescope structures. These prototypes will be of fundamental importance for assessing the design performance and applying improvements before the pre-production phase. All these activities will culminate in the Critical Design Review of the whole project, which is scheduled for late 2014.
CTA’s project organization also sees a turning point in 2014. The present preparatory phase, funded by FP7, is ending. For the next phase, during which talks about site deployment will start, it would be useful to establish an interim legal entity to bridge the present organization towards the final open observatory. Different options are under discussion for both this intermediate phase and also for the long-term organization of CTA. At present it seems that a German GmbH is the most straightforward option for the interim entity. A final word on this should arrive soon, but the discussion about the evolution of the whole organization towards the final observatory, which involves many different organizations, including the funding agencies, is unlikely to stop any time soon.
Many fundamental things are going to happen in 2014 for the CTA project at every level – technical, scientific and managerial. Let’s wish this challenging and interesting project bon voyage – and please stay tuned to hear further exciting news!!