Science: Virgo back on-line

[bystander]

European gravitational wave detector back in action
Science Insider | 2017 Aug 01

[img3="Virgo stretches its 3-kilometer arms across the Tuscan plain near Pisa, Italy.
Credit: Virgo Collaboration/N. Baldocchi "]http://www.sciencemag.org/sites/default ... Aerial.jpg[/img3][hr][/hr]

Virgo, Europe’s premier gravitational wave detector, today joined forces with the two detectors of its U.S. counterpart, the Laser Interferometer Gravitational-Wave Observatory (LIGO), in the hunt for ripples in space-time following a €24 million upgrade. In March, the two observatories were meant to begin joint observations—which allow researchers to pinpoint the locations of sources of cosmic waves, such as merging black holes, more accurately. But problems with fragile glass-fiber suspensions for Virgo’s mirrors delayed its startup. Engineers were forced to temporarily install wire suspensions, reducing Virgo’s sensitivity; it will now take a supporting role during the last few weeks of LIGO’s current observing run. ...

The upgraded Virgo was due to join LIGO during its second observing run, which began in November 2016 but problems with the suspensions holding up the mirrors (these bounce the laser beam back and forth along the arms) led to delays. The run was due to finish in May, but the LIGO team, hoping for at least a brief period of joint observation, has stretched out the timeline as the Virgo upgrade neared completion. Because of Virgo’s loss of sensitivity with the wire suspensions, it will not be able to detect gravitational waves independently, but it will be able to help confirm a potential detection made by LIGO and locate sources in the sky with greater accuracy. LIGO’s run will finally finish on 25 August.

Both observatories will then carry out further upgrades, including restoration of Virgo’s glass-fiber suspensions, before the next run starts in the second half of 2018.

[MargaritaMc]

VIRGO's own press release
http://public.virgo-gw.eu/virgo-joins-l ... ng-period/

This is a useful looking web page with news updates about the LIGO-VIRGO collaboration.
http://www.virgo-gw.eu/#news

[neufer]

<<Cascina is a comune (municipality) in the Province of Pisa in the Italian region Tuscany, located about 60 kilometres west of Florence and about 13 kilometres southeast of Pisa. Cascina is located on the left shore of the Arno River, on a markedly plain terrain. The comune borders the following municipalities: Calcinaia, Collesalvetti, Crespina, Lari, Pisa, Pontedera, San Giuliano Terme, Vicopisano. Cascina is home to the European Gravitational Observatory and the Virgo interferometer, one of the few facilities in the World for the search for gravitational waves.

The first mention of Cascina is from a document of 750 AD. The origin of the name is uncertain, but it could derive from Casina ("Small House"), or from the creek that crossed it (now disappeared), or from an Etruscan personal name, Latinized as Cassenius.

On 26 July 1364, the eponymous battle between the armies of Pisa and Florence was fought here. The event was later reproduced by Michelangelo in painting of which now preparatory drawings and a copy by Aristotile da Sangallo (also known as Bastiano da Sangallo) exist. The city had in fact a strategical importance as a fortified stronghold on the main road connecting the two cities.>>

[MargaritaMc]

There's something rather satisfying about a gravitational wave detector being in the province of Pisa, where Galileo "is said to have" done his experiment about gravity.
https://en.m.wikipedia.org/wiki/Galileo ... experiment