h25

Despite the difficult tasks facing us, Advanced Virgo is showing progress as witnessed by the end of civil engineering works and the delivery of many components to the site. The External Injection Bench and its new seismic isolating support have been installed in the laser lab together with the laser bench (although it still has the old legs). The four 2 m diameter cylinders to transform the Signal Recycling Tower into a full sized tower are stored in the Central Building. The new Input Mode Cleaner mirror is ready in its payload. The first large cryotrap is in the West Terminal building, ready to be installed and the other three cryotraps are being tested in the factory (as can be seen in the cover picture). In comparison the cover of h23 represented a cryotrap only as a technical drawing.
The effort to achieve an operating Advanced Virgo is boosted by the recent discovery of the imprint of primordial gravitational waves on the cosmic microwave background (http://www.cfa.harvard.edu/news/2014-05). This is the second indirect evidence of the existence of gravitational waves, after the Hulse and Taylor binary. Only the direct detection is missing, which is the Virgo-LIGO duty.
The editorial team of h wishes all the best to Advanced Virgo and to all the readers.

C.Bradaschia
Chief Editor