S3 analysis posted on homepage
29 Mar 2007 22:22:17 UTC
Topic 192558
(moderation:
In all shortness, these are the 2 paragraphs I found most interesting after some quick reading. The future seem promising, especially when the advanced LIGO comes up. Any comments?
"We therefore conclude that we have not seen any credible evidence for pulsar signals in the Einstein@Home search on S3 data. This is not surprising. The LIGO instruments were still undergoing commissioning to reach their design sensitivity at the time of the S3 science run. And even at design sensitivity, the level of noise in the instruments is high enough that it may obscure gravitational wave signals present in the data."
"After another planned long science run (S6), the LIGO Lab, the LIGO Scientific Collaboration, and international partners will start to install an Advanced LIGO upgrade [43], which will improve the strain sensitivity by a factor of 10. Since the volume of space that the instrument can see grows as the cube of the distance, this means that the number of sources that can be detected will be up to 1,000 times greater than for initial LIGO. New detector hardware will be installed in the existing LIGO vacuum systems at the LIGO Hanford and Livingston Observatories and will replace the present instruments. Advanced LIGO will transform gravitational wave science into a real observational tool. It is anticipated that these new instruments may discover new gravitational-wave sources as often as once per day, with excellent signal strength, allowing details of the waveforms to be read off and compared with theories of neutron stars, black holes, and other highly relativistic objects."
S3 analysis posted on homepage
)
As more observatories come on line (see also prof.Allen's post about VIRGO and GEO) I am wondering about a possible use of prof. Joseph Weber's idea of searching for coincident events, which dates back to the Sixties.
Tullio
RE: As more observatories
)
That's implicit in the whole shebang. The idea of separated detectors and the relative near co-incidence of arrival of signals allows for both confirmation of a particular wave's reception, and more hopefully a deduction of the direction of the source. Each detector separately is fairly 'omni-directional' in sensitivity. Having many spaced detectors ( and the more the better! ) gives you an extended array to base such analyses on. Hence the inclusion of GEO and VIRGO ( TAMA .... ) data when on-line. ( see here )
It's true that the expected performance of the advanced LIGO is quite a jump from now. I remember one figure being: what is currently collected in one week now, will take less than one hour on advanced LIGO then. So the issues of data analysis, economy, efficiency etc will then be more acute than now. Organization of the pipeline ( largely E@H ) will be crucial. The learning process currently being undergone will yield dividends even then.... :-)
Cheers, Mike.
I have made this letter longer than usual because I lack the time to make it shorter ...
... and my other CPU is a Ryzen 5950X :-) Blaise Pascal
I am glad to take even a
)
I am glad to take even a small part in this project. In 1970 I published an article by prof. Peter G. Bergmann of Syracuse University in the Mondadori Yearbook of Science@Technology, then other articles by profs. Remo Ruffini and Bruno Bertotti on GR and the search for GW. I also edited the Italian edition of prof. Bergmann's book "The Riddle of Gravitation". It makes me feel younger (I am 71) to crunch Einstein@home data on my PII running SuSE Linux 10.1.
Tullio
RE: I remember one figure
)
Mike, I think the figure you remember is that the "science reach" is about the same for a week of initial LIGO and advanced LIGO. For a fully coherent pulsar search, the strain you could see improves as the square root of observation time. Advanced LIGO's noise will be more than a factor 10 better, so an hour of that is worth more than 100 hours (4 days) of initial LIGO. That figure is different for different types of searches, including Einstein@Home which is not a fully coherent search, but the general idea that advanced LIGO will be a huge improvement is right. And although the data flow may not be (much) larger, we are indeed learning valuable lessons from Einstein@Home and our other analyses.
Ben