Internship contract for a period of 6 months within the EGO Interferometer Technology Department, funded by the EGO Consortium. Applicants should be in their last years of study in physics, astrophysics or geophysics. The work will be at a level of Master thesis (equivalent to thesis for “laurea specialistica” in Italian).
Type of contract
Internship contract for a period of 6 months within the EGO Interferometer Technology Department, funded by the EGO Consortium.
Description
Virgo is a 3km laser interferometer for the detection of Gravitational Waves (GW), located near Pisa, Italy. The European Gravitational Observatory (EGO, www.ego-gw.it) is the laboratory hosting and operating Virgo. Since the first GW detection in 2015, Virgo and the two LIGO interferometers in the USA have jointly detected several GW signals, opening the new era of GW astronomy.
A 1-year-long observation run (“O3”) was concluded in March 2020. The next observation run should start mid-2022: in the meantime, all detectors are being upgraded and work is ongoing to improve their performance, building on experience gained during the O3 run. The present internship proposal falls under the latter category.
Earthquake waves typically excite the seismic attenuation systems that suspend the Virgo detector optics and, if no action is taken, can make the interferometer lose the controlled operation condition, a mode that is mandatory to be sensitive to GWs coming from the cosmos.
The time to recover from one such control loss can be long, up to a few hours depending on the shake intensity, and sensibly reduce the detector duty cycle. Therefore, knowing ahead of time that potentially strong seismic waves are coming from far away on Earth is a crucial information as one could then anticipate the quake and take actions to potentially mitigate it.
A first version of an earthquake early warning system has been in use during the O3 observation run. It relies on information provided by the US-centric USGS seismic network to perform an estimate of the arrival time and intensity of S, P and Rayleigh waves. When a warning was received and processed in time (that is before the arrival of the seismic waves), the Virgo interferometer was manually set in a more robust configuration (the so-called “EQ-mode”) that increases its chance to survive the quake.
We plan to improve this alert system in view of future observing runs and for application in next generation GW detectors, like the Einstein Telescope. Our goals are to improve the efficiency of the alerts, the precision of the seismic wave timing and intensity estimates, and eventually to automate the switch to the EQ-mode.
On this topic, Virgo is collaborating with the Istituto Nazionale di Geofisica e Vulcanologia (INGV). To improve the warning efficiency, we are considering the addition of information provided by Italy-centric systems specifically designed for earthquake early warning. In particular, one such Earthquake Early Warning system (EEWS) based on a machine-learning based algorithm is under study at INGV and has been preliminary tested for Virgo.
We are looking for a motivated student to work on the definition, tuning and finalization of this EEWS for Virgo. At this stage, the project includes a deep analysis of the relevant seismicity recorded during the “O2” (August 2017) and O3 observing runs to define magnitude and distance thresholds and compare the recorded ground shaking (amplitude and frequency) at Virgo with predictions. Then, we expect to use the results from the above analysis to implement the new monitoring system that includes rapid scenarios for the ground shaking caused by any forthcoming large teleseismic and regional earthquake.
Requirements
Applicants should be in their last years of study in physics, astrophysics or geophysics. The work will be at a level of Master thesis (equivalent to thesis for “laurea specialistica” in Italian).
English required. Knowledge in geophysics, experience in programing (python, Matlab, etc.) will be assets.
European citizenship, no criminal convictions.
Place of work
EGO – European Gravitational Observatory – via E. Amaldi n.5 cap 56021 Loc. S. Stefano a Macerata – Cascina (Pisa) ITALY.
This internship will be carried out in the Interferometer Technology Department.
Considering the lack of public means of transport to reach the site, it is preferable having a car. Depending on how the covid-19 pandemic evolves in the coming months, the present internship may have to be done partly or totally from remote.
How to apply?
Interested candidates are invited to fill in the Internship Application Form and send it, together with the CV, to internships@ego-gw.it
Further information
For the whole duration of the internship, EGO will pay a gross monthly wage of 500,00 euro and the lunch at its canteen during working days.
Closing date for applications
Until position is filled.
Contact
Irene Fiori, PhD
Email: irene.fiori@ego-gw.it
Phone: +39 050 752 355
Nicolas Arnaud, PhD
Email: narnaud@lal.in2p3.fr
Phone: +39 050 752 314