Plans for near future of E@H ?


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astro-marwil
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Message 119870 - Posted 1 Nov 2012 11:24:38 UTC

    Hallo!
    FGRP1 is out of data and S6LV1 will end close to the end of this year.
    So I had a look into LSC-Virgo data analysis white paper - many thanks to joe areeda for posting this((:-))) -. But the only I found directly related to E@H was on page 131, in chaper 7 "LSC Computing and Software" the last block: "The LSC also developed the Einstein@Home project to leverage an alternative distributed computing paradigm for its most formidable computing challenge, the search for gravitational waves from isolated pulsars. The pulsar analysis puts reduced demand on quick turn-around and has low data flow, but requires PFlops of computing power. The ....". (We just reached 0.7PFLOPs.)
    On A@H are no following up projects for test now.
    For fresh data form the Advanced LIGO detectors we will have to wait for another year at minimum, according to the official time schedule.
    So what will be the near future of E@H? Will we crunch BRP1 tasks on our CPUs, which is much less effective?

    For a short answer we will be pleased.

    Kind regards and happy crunching
    Martin

    P.S.: I found the "LSC-Virgo data analysis white paper" still very much interesting.
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    Message 119874 - Posted 1 Nov 2012 14:57:38 UTC

      Last modified: 1 Nov 2012 15:12:40 UTC

      For fresh data form the Advanced LIGO detectors we will have to wait for another year at minimum


      Correct. But there may still something to be found in the existing data. For "continuous waves" searches the computing power is still what limits the sensitivity of a search, which roughly translates to the depth we could dig into space.

      We are already preparing the next GW search, which will focus fewer promising sky positions, allowing us to reach out further than ever before.


      Will we crunch BRP1 tasks on our CPUs, which is much less effective?


      You think? In contrast to the GW search the Radio-Pulsar search lead to a couple of really interesting new discoveries. In my very personal view this is more effective than the GW searches we did so far.

      We still haven't caught up with Arecibo data production, AFAIK we haven't yet processed any data from 2012. There are still a lot of Radio Pulsars out there waiting to be discovered!

      And finally the Gamma-Ray Pulsar search is suspended because we ran out of manpower, not of data. I hope we can resume that work soon.


      For a short answer we will be pleased.


      Short answer to a long question?


      BM

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      Message 119875 - Posted 1 Nov 2012 16:19:18 UTC - in response to Message 119874.

        Hallo BM!
        Thank you for quick answering.

        For "continuous waves" searches the computing power is still what limits the sensitivity of a search, which roughly translates to the depth we could dig into space.

        I believe so. I remember, in early days of EaH we where happy reaching 100GFLOPS, and one task lasted much more than a year to finish. Now we have 7000 times of this crunching power, which gives more freedome for more complex project tasks and longer averaging times, resulting in higher sensitivity.

        In contrast to the GW search the Radio-Pulsar search lead to a couple of really interesting new discoveries. In my very personal view this is more effective than the GW searches we did so far.

        Sorry, my sentence was incomplete. I compared crunching on CPU / GPU. If I remmber correctly the BRP tasks where running for about 10h on CPU instead of some 10min on GPU. Comparing the requiered electrical power to crunch 1 BRP task, I suggest the GPU is also in forehand. Did someone test this? The figure is highly dependend on the used hardware.

        We are already preparing the next GW search, which will focus fewer promising sky positions, allowing us to reach out further than ever before.

        ..... I hope we can resume that work soon.

        We´re happy to heare this and do wait.

        Kind regards and happy crunching
        Martin
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        Message 119876 - Posted 1 Nov 2012 16:45:11 UTC - in response to Message 119874.

          You think? In contrast to the GW search the Radio-Pulsar search lead to a couple of really interesting new discoveries. In my very personal view this is more effective than the GW searches we did so far.

          So, Einstein@Home can profit from the results of pulsar hunting?
          I always thought that this secondary project only diverts the resources.

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          Message 119879 - Posted 1 Nov 2012 19:46:33 UTC - in response to Message 119876.

            Last modified: 1 Nov 2012 20:12:21 UTC

            You think? In contrast to the GW search the Radio-Pulsar search lead to a couple of really interesting new discoveries. In my very personal view this is more effective than the GW searches we did so far.


            So, Einstein@Home can profit from the results of pulsar hunting?
            I always thought that this secondary project only diverts the resources.


            The ultimate goal of Einstein@Home is to contribute to a better understanding of our universe by studying neutron stars, objects with such extreme conditions that they drive our theories of matter and forces to the limits (and possibly beyond), allowing to test and refine these.

            The only way we can study these objects is through their emissions we could detect on (or near) earth - electromagnetic waves (like radio or gamma) or gravitational waves.

            In that sense every result, in particular every new discovery of a pulsar, helps a bit to understand - what is possible, and what not, which theories and models do match best what we observe. So all three searches currently running on Einstein@Home do help the general goal.

            As for the more narrow goal of detecting gravitational waves, the radio pulsar discoveries of Einstein@Home do help to form pulsar timing arrays that will help us to measure gravitational waves of a different wavelength than what the LIGO detectors and the GW search on Einstein@Home is sensitive for.

            Finally the radio pulsar search allows us to keep and even increase our user base and thus computing power, even during periods when there is no new data from the GW detectors available - like now.

            BM

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            Message 119881 - Posted 1 Nov 2012 20:17:03 UTC - in response to Message 119875.

              Last modified: 1 Nov 2012 20:17:31 UTC

              In contrast to the GW search the Radio-Pulsar search lead to a couple of really interesting new discoveries. In my very personal view this is more effective than the GW searches we did so far.

              Sorry, my sentence was incomplete. I compared crunching on CPU / GPU. If I remmber correctly the BRP tasks where running for about 10h on CPU instead of some 10min on GPU. Comparing the requiered electrical power to crunch 1 BRP task, I suggest the GPU is also in forehand. Did someone test this? The figure is highly dependend on the used hardware.


              So you meant 'efficient' instead of 'effective'.

              BM

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              Message 119882 - Posted 1 Nov 2012 21:48:56 UTC

                Last modified: 1 Nov 2012 23:24:18 UTC

                I remember the radio pulsar search as being initiated to solve several problems : an unavoidable hiatus in new data from the IFO's ie. keep the punters interested while we await GW detector upgrades, to help the PALFA consortium's need for processing their data, and to orthogonally study the same class of stars/systems as GW's will anyway. The gamma search is along the same lines.

                If that understanding is correct then : the radio and gamma work have done brilliantly. As for whether it is 'correct' for the E@H project to have solved such issues is a higher question. In any case the value of GW work has not been lost, indeed upper limits have now been placed on certain signal types ( of interest to observers and theorists alike ) not to mention an enormous slab of valuable experience in running the analysis 'pipeline' that E@H is a part of. For the first, or for that matter subsequent, GW detections then validation and confidence in the entire enterprise will be crucial.

                As a 'leading edge' activity I think it is quite reasonable & healthy to assess directions from time to time, to reflect upon progress or otherwise and try to make good guesses for the future. Else it wouldn't be called 'research' would it ?? :-)

                Cheers, Mike.
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                Message 120271 - Posted 21 Nov 2012 10:08:56 UTC - in response to Message 119874.

                  We are already preparing the next GW search, which will focus fewer promising sky positions, allowing us to reach out further than ever before.


                  Actually we will first extend the current S6 LineVeto search a bit to higher frequencies.

                  A number of recent publications and own results of pulsar searches (in radio and gamma-ray) lead us to think that there is a larger population of 'younger' (i.e. faster spinning) pulsars than we expected when we initially set up the search.

                  Note that this is another example of interaction between the different pulsar searches on Einstein@Home.

                  BM

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                  Message 120490 - Posted 27 Nov 2012 7:37:29 UTC - in response to Message 120271.

                    We are already preparing the next GW search, which will focus fewer promising sky positions, allowing us to reach out further than ever before.


                    Actually we will first extend the current S6 LineVeto search a bit to higher frequencies.

                    A number of recent publications and own results of pulsar searches (in radio and gamma-ray) lead us to think that there is a larger population of 'younger' (i.e. faster spinning) pulsars than we expected when we initially set up the search.

                    Note that this is another example of interaction between the different pulsar searches on Einstein@Home.

                    BM

                    Bernd what frequencies are we going out to ? Do we still have the WU count per frequency going like quadratic to frequency ?

                    Cheers, Mike.
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                    Message 120493 - Posted 27 Nov 2012 10:56:38 UTC - in response to Message 120490.

                      Last modified: 27 Nov 2012 10:56:59 UTC

                      Bernd what frequencies are we going out to ?


                      This is still being discussed. Most likely an additional 50Hz or so. The higher we get, the more we would need to include a possible 2nd order frequency derivative. Our current code should be able to do that, but that hasn't been (sufficiently) validated yet.

                      Do we still have the WU count per frequency going like quadratic to frequency ?


                      Yes, as long as we stick to only first frequency derivative ("spindown").

                      We are currently working on the Application. It will be only slightly different, returning two result files, one containing the older "2F" statistics, the other containing the newer "LV". In principle we are extending both previous runs (S6LV1 and S6Bucket) at once.

                      BM

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                      Message 120522 - Posted 27 Nov 2012 22:41:06 UTC

                        Ah I see. Not only faster spinning, but faster evolving too.

                        Cheers, Mike
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                        Message 121658 - Posted 28 Dec 2012 14:36:40 UTC

                          We'll continue with the BRP4 search indefinitely. First we need to catch up with the data backlog of about 13,000 beams (this will take a couple of months at the current rates) then we'll continue in the steady-state. PALFA is taking about 50 new beams of data per day, on the average, so this search will be running for some years, at least for as long as PALFA is collecting new data.


                          Since we are processing an average of 150beams/day, does that mean that we are going to have a shortage of BRP4 tasks to feed all the GPU´s?
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                          Message 121664 - Posted 29 Dec 2012 13:26:12 UTC - in response to Message 121658.

                            Last modified: 29 Dec 2012 13:45:44 UTC

                            We'll continue with the BRP4 search indefinitely. First we need to catch up with the data backlog of about 13,000 beams (this will take a couple of months at the current rates) then we'll continue in the steady-state. PALFA is taking about 50 new beams of data per day, on the average, so this search will be running for some years, at least for as long as PALFA is collecting new data.


                            Since we are processing an average of 150beams/day, does that mean that we are going to have a shortage of BRP4 tasks to feed all the GPU´s?


                            Not necessarily.

                            - The 13,000 beams (now rather 10,000) refer to the data that has been so far copied to the AEI. There is a bit more data to fetch from Cornell (~6000 beams IIRC).

                            - We could widen the parameter space that the data is searched for. This will give us more workunits per data.

                            - There is an OpenCL version of the Gamma-Ray pulsar search being actively worked on, I think it should be ready before the BRP search catches up with the Arecibo data.

                            - There is also (yet) another attempt to make use of the GPUs for the GW search, but this will take a little longer. Certainly not for the planned "extension" run, but possibly for the next; if not ready for the run's start, then we still might issue it when the run's in progress.

                            - While at it, the GW "extension" run will be named "S6BucketLVE". It has been successfully tested over on Albert and the launch on Einstein is projected for Jan 9.

                            BM

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                            Message 121666 - Posted 29 Dec 2012 14:13:19 UTC

                              Thanks for the detalhed answer Bernd.

                              It's good to have a project who comunicate this well with the crunchers.

                              Filipe
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                              Message 123188 - Posted 2 Mar 2013 12:17:58 UTC

                                Last modified: 2 Mar 2013 12:18:09 UTC

                                - Are you catching up wit the the Arecibo data?

                                - Is there any news about the open cl app for the Gamma Ray shearch?
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                                Message 123193 - Posted 2 Mar 2013 16:21:46 UTC - in response to Message 123188.

                                  - Are you catching up wit the the Arecibo data?

                                  - Is there any news about the open cl app for the Gamma Ray shearch?


                                  Hi!

                                  As for the Gamma Ray search, I think we can expect to start a full test of an app on Albert@Home in the next 7- 10 days or so.

                                  Cheers
                                  HB

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                                  Message 123400 - Posted 11 Mar 2013 16:25:51 UTC - in response to Message 123188.

                                    - Are you catching up wit the the Arecibo data?


                                    The time until we catch up with the backlog of Arecibo data is roughly shown by the "Days to process remaining data" on the Server status page.

                                    We're currently gathering more data to keep our analysis pipeline fed, e.g. from another survey of the Parkes telescope.

                                    BM

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                                    Message 123515 - Posted 18 Mar 2013 10:20:35 UTC - in response to Message 123193.

                                      As for the Gamma Ray search, I think we can expect to start a full test of an app on Albert@Home in the next 7- 10 days or so.


                                      FGRP2 OpneCL App launched on Albert.

                                      BM

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                                      Message 123516 - Posted 18 Mar 2013 10:49:27 UTC - in response to Message 123515.



                                        FGRP2 OpneCL App launched on Albert.

                                        BM


                                        Thank you to inform us. However I have a question.
                                        Is this new application for ati only? Certainly, we'd like to have something similar for Nvidia.

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                                        Message 123517 - Posted 18 Mar 2013 11:09:39 UTC

                                          See the related thread on Albert@Home.

                                          BM

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                                          Message 123577 - Posted 21 Mar 2013 11:43:08 UTC - in response to Message 123400.

                                            We're currently gathering more data to keep our analysis pipeline fed, e.g. from another survey of the Parkes telescope.


                                            This is done as a new "application" (in BOINC terms) that will get the new label "BRP5". It is currently being tested on Albert, too ("Binary Radio Pulsar Search (Perseus Arm Survey)").

                                            BM

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                                            Message 123642 - Posted 25 Mar 2013 15:31:21 UTC - in response to Message 123577.

                                              We're currently gathering more data to keep our analysis pipeline fed, e.g. from another survey of the Parkes telescope.


                                              This is done as a new "application" (in BOINC terms) that will get the new label "BRP5". It is currently being tested on Albert, too ("Binary Radio Pulsar Search (Perseus Arm Survey)").


                                              There's some more info over here.

                                              BM

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                                              Message 125872 - Posted 19 Jul 2013 15:37:31 UTC - in response to Message 119879.

                                                You think? In contrast to the GW search the Radio-Pulsar search lead to a couple of really interesting new discoveries. In my very personal view this is more effective than the GW searches we did so far.


                                                So, Einstein@Home can profit from the results of pulsar hunting?
                                                I always thought that this secondary project only diverts the resources.


                                                The ultimate goal of Einstein@Home is to contribute to a better understanding of our universe by studying neutron stars, objects with such extreme conditions that they drive our theories of matter and forces to the limits (and possibly beyond), allowing to test and refine these.

                                                The only way we can study these objects is through their emissions we could detect on (or near) earth - electromagnetic waves (like radio or gamma) or gravitational waves.

                                                In that sense every result, in particular every new discovery of a pulsar, helps a bit to understand - what is possible, and what not, which theories and models do match best what we observe. So all three searches currently running on Einstein@Home do help the general goal.

                                                As for the more narrow goal of detecting gravitational waves, the radio pulsar discoveries of Einstein@Home do help to form pulsar timing arrays that will help us to measure gravitational waves of a different wavelength than what the LIGO detectors and the GW search on Einstein@Home is sensitive for.

                                                Finally the radio pulsar search allows us to keep and even increase our user base and thus computing power, even during periods when there is no new data from the GW detectors available - like now.

                                                BM


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                                                Message 125873 - Posted 19 Jul 2013 15:48:55 UTC - in response to Message 119874.

                                                  The ultimate goal of Einstein@Home is to contribute to a better understanding of our universe by studying neutron stars, objects with such extreme conditions that they drive our theories of matter and forces to the limits (and possibly beyond), allowing to test and refine these.


                                                  Boy am I in the wrong place. I thought we were trying to find and contact ET's...come to think of it, I think this has already been done..



                                                  No reply needed. It would only start trouble :)

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                                                  Message 131535 - Posted 16 Jun 2014 10:41:41 UTC

                                                    Any update?

                                                    What is coming after S6 casa and FGRP3?
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                                                    Message 131537 - Posted 16 Jun 2014 11:40:12 UTC - in response to Message 131535.

                                                      FGRP3 was originally meant to process the new data published by FERMI last November. However at the launch of FGRP3, we couldn't finish the preparation of this data for our search, so we launched FGRP3 first to finish the analysis of the older data set that was left over from the previous run FGRP2. When the current FGRP3 runs out of that data, we intend to have the new data prepared. Work on that is well underway. Also we are working on improvements on the analysis code that will give us an increase in sensitivity of ~25% without additional computing cost.

                                                      S6CasA is actually part of a larger effort that we internally call "S6Directed", i.e. an analysis of "S6" data targeting single positions (hopefully GW sources) in the sky. We started with the most promising "Cassiopeia A", and will then simply move on to the next target (there are about a dozen on our list). We are also working on improving the analysis code for this, trying to make it more efficient and sensitive.

                                                      BM

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                                                      Message 131538 - Posted 16 Jun 2014 13:06:05 UTC

                                                        (there are about a dozen on our list)


                                                        12 targets. Uau! This is going to take some serious computing power.

                                                        S6 casa is running for more than a year now.
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                                                        Message 131542 - Posted 16 Jun 2014 19:25:00 UTC - in response to Message 131538.

                                                          Last modified: 16 Jun 2014 19:25:56 UTC

                                                          Well, we intend to spend less time on the other targets than we did on CasA, and we hope that the more efficient search code will help to not lose too much sensitivity. We also probably won't cover all possible sources; we will probably cut the run short when more sensitive data from the advanced detectors becomes available for analysis, which is currently planned to happen end of next year.

                                                          BM

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                                                          Message 131543 - Posted 16 Jun 2014 21:24:58 UTC - in response to Message 131537.

                                                            Last modified: 16 Jun 2014 21:31:22 UTC

                                                            Hallo!

                                                            We started with the most promising "Cassiopeia A", and will then simply move on to the next target (there are about a dozen on our list).

                                                            I would like to know, what is so promissing on Cassiopeia A. It´s not sure whether it´s a black hole or a pulsar, whose magnetic axis is never directed to earth, as the radition activity doesn´t show a measurable periodicity. Where as the Crab-Pulsar is just 57% as far away as Cas A and so giving 3 times stronger GW signal, Further the Crab-Pulsar is also a young pulsar, just about 1000 years old, and does show glitches in the rotation periode, which are interpreted as reorientation of his material. This should result in GWs, ok? Furthermore the Crab-Pulsar is realy very well controlled by the Jodrell Bank Observatory. So one do know the exact period at that time and when such glitches happend and how strong they are. So the Crab-Pulsar would have been on the top of my list.
                                                            Kind regards an happy crunching
                                                            Martin
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                                                            Message 131621 - Posted 20 Jun 2014 14:51:10 UTC - in response to Message 131543.

                                                              Hallo!
                                                              We started with the most promising "Cassiopeia A", and will then simply move on to the next target (there are about a dozen on our list).

                                                              I would like to know, what is so promissing on Cassiopeia A. It´s not sure whether it´s a black hole or a pulsar, whose magnetic axis is never directed to earth, as the radition activity doesn´t show a measurable periodicity. Where as the Crab-Pulsar is just 57% as far away as Cas A and so giving 3 times stronger GW signal, Further the Crab-Pulsar is also a young pulsar, just about 1000 years old, and does show glitches in the rotation periode, which are interpreted as reorientation of his material. This should result in GWs, ok? Furthermore the Crab-Pulsar is realy very well controlled by the Jodrell Bank Observatory. So one do know the exact period at that time and when such glitches happend and how strong they are. So the Crab-Pulsar would have been on the top of my list.
                                                              Kind regards an happy crunching
                                                              Martin


                                                              That is exactly the point: Because the rotation of the Crab-pulsar is so well understood, it doesn't take a massive network of computers like Einstein@home to search for GWs from it (at least as long as you assume that the GW frequency is related to the EM pulse frequency in a known way (like the first being twice the latter for a certain emission mechanism), which is a reasonable assumption, but by no means certain). So most searches involving the Crab-pulsar are "targeted" or "narrow band" searches, where the search frequency and frequency derivatives of the GW signal are very tightly constrained by EM observations. So this kind of search is not that computationally expensive.

                                                              For Cas A however, as you mentioned, this is not the case. So we need to do a much more expensive "directed" search here. The sky position of the source is known from EM observations, but for the frequency and frequency derivative(s), we need to try an awful lot of independent templates, and that's what Einstein@home can do really well.

                                                              HB

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                                                              Message 131721 - Posted 24 Jun 2014 20:59:56 UTC - in response to Message 131621.

                                                                Last modified: 24 Jun 2014 21:01:16 UTC

                                                                Hallo Bikeman!

                                                                Hallo!

                                                                We started with the most promising "Cassiopeia A", and will then simply move on to the next target (there are about a dozen on our list).


                                                                I would like to know, what is so promissing on Cassiopeia A. It´s not sure whether it´s a black hole or a pulsar, whose magnetic axis is never directed to earth, as the radition activity doesn´t show a measurable periodicity. Where as the Crab-Pulsar is just 57% as far away as Cas A and so giving 3 times stronger GW signal, Further the Crab-Pulsar is also a young pulsar, just about 1000 years old, and does show glitches in the rotation periode, which are interpreted as reorientation of his material. This should result in GWs, ok? Furthermore the Crab-Pulsar is realy very well controlled by the Jodrell Bank Observatory. So one do know the exact period at that time and when such glitches happend and how strong they are. So the Crab-Pulsar would have been on the top of my list. Furthermore, doesn´t these glitches - abrupt changes in rotational speed - emit GW-power?
                                                                Kind regards an happy crunching
                                                                Martin

                                                                ..... So most searches involving the Crab-pulsar are "targeted" or "narrow band" searches, where the search frequency and frequency derivatives of the GW signal are very tightly constrained by EM observations. So this kind of search is not that computationally expensive. ....

                                                                From this I conclude, that it was already for a limited range of parameters done without success. So, will it be repeated here with a much wider field of parameters? Furthermore, doesn´t these glitches - abrupt changes in rotational speed likely due to material reorientation inside the pulsar - emit GW-power?

                                                                Kind regards and happy crunching
                                                                Martin
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                                                                Profile Bikeman (Heinz-Bernd Eggenstein)
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                                                                Message 131732 - Posted 25 Jun 2014 9:51:50 UTC - in response to Message 131721.


                                                                  From this I conclude, that it was already for a limited range of parameters done without success. So, will it be repeated here with a much wider field of parameters? Furthermore, doesn´t these glitches - abrupt changes in rotational speed likely due to material reorientation inside the pulsar - emit GW-power?

                                                                  Kind regards and happy crunching
                                                                  Martin


                                                                  At this point I have to caution that I'm not a physicist, but hey, I can point you to what physicists have done:

                                                                  GW searches for the Crab pulsar:

                                                                  A presentation with a birds-eye view of observational results,

                                                                  http://gr20-amaldi10.edu.pl/userfiles/12-01_Marie Anne Bizouard - Observational Results from Ground-based___.pdf

                                                                  A pointer to results for Crab pulsar and Vela pulsar (another well studied young pulsar and a real champion when it comes to glitching) is on page 44:

                                                                  Vela: Astrophys. J. 737 (2011) 93 : http://iopscience.iop.org/0004-637X/737/2/93/
                                                                  Crab and others: Astrophys. J. 713 (2010) 671 : http://iopscience.iop.org/0004-637X/713/1/671/

                                                                  There might be newer studies but you will get an idea from those papers.

                                                                  You will also easily find papers that discuss how/if pulsar glitches (and whatever happens before or after the glitch) might cause detectable GWs:


                                                                  PhysRevD.84.023007, also on http://arxiv.org/pdf/1104.1704.pdf


                                                                  http://www.phys.ufl.edu/ireu/IREU2013/pdf_reports/Corey_Bathurst_Final_Report.pdf


                                                                  I'm not aware of any plans to do narrow-band or even targeted searches for Einstein@Home. That's simply not the kind of search we are specializing in, E@H is better at all-sky searches or directed searches if you are looking for continuous gravitational waves.

                                                                  Cheers
                                                                  HB

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                                                                  Message 131753 - Posted 26 Jun 2014 3:28:14 UTC

                                                                    Last modified: 26 Jun 2014 3:36:39 UTC

                                                                    Well, I'm game ! :-0

                                                                    My reading of Prix et al seems to indicate that glitching can have a detectable GW signature(s), under the curious title of 'transient continuous waves'. These are further subdivided into 'repeating' and 'non-repeating' transient continuous waves. :-)

                                                                    This appears to mean that processes either causative to, or consequent upon, the glitching events generate GW emission regularities that decay in amplitude over far shorter time periods ( eg. weeks ) than the typical winding down behaviour of the spinning neutron star. That in turn depends upon the physics, or model thereof, applied to the problem.

                                                                    As for all the Bayesian stuff : aarggh .... I've never really grasped Bayes .... :-(

                                                                    However for us simple souls there is ( my emphasis ) :

                                                                    In addition to the fully coherent search method, we have derived the necessary formalism for a semi-coherent transient search, which could be used to perform an all-sky, all-frequency wide parameter-space transient search, for example running on Einstein@Home. More work is required to fully develop and implement this approach.

                                                                    Cheers, Mike.

                                                                    ( edit ) As far as I can tell : one takes the 'standard' continuous wave model and looks at detection within shorter 'windows'. This necessarily affects the detection statistics, or if you like, the confidence that one can place upon a positive result from a given template actually being evidence for a real phenomenon in the sky. That is : what likelihood may be assigned to us being fooled by random/uncorrelated noise.
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                                                                    Profile Bernd Machenschalk
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                                                                    Message 132072 - Posted 9 Jul 2014 9:10:57 UTC - in response to Message 131732.

                                                                      Last modified: 9 Jul 2014 9:11:29 UTC

                                                                      I'm not aware of any plans to do narrow-band or even targeted searches for Einstein@Home. That's simply not the kind of search we are specializing in, E@H is better at all-sky searches or directed searches if you are looking for continuous gravitational waves.


                                                                      The main argument here is that these searches have a computing time / data volume ratio that make these infeasible for volunteer computing. Your computers will spend more time on downloading data for a task than on computing it.

                                                                      BM

                                                                      Profile Bernd Machenschalk
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                                                                      Message 132073 - Posted 9 Jul 2014 9:19:45 UTC - in response to Message 131537.

                                                                        Last modified: 10 Jul 2014 7:34:23 UTC

                                                                        S6CasA is actually part of a larger effort that we internally call "S6Directed", i.e. an analysis of "S6" data targeting single positions (hopefully GW sources) in the sky. We started with the most promising "Cassiopeia A", and will then simply move on to the next target (there are about a dozen on our list). We are also working on improving the analysis code for this, trying to make it more efficient and sensitive.


                                                                        Update on that: At present it looks like there will be numerous and substantial changes to the analysis application code which effect e.g. on the runtime behavior are difficult to foresee. We will probably have a series of short "engineering runs" to get a better understanding of the new code in the heterogeneous environment of Einstein@Home before we will continue with actual searches.

                                                                        BM

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                                                                        Message 132094 - Posted 10 Jul 2014 6:35:23 UTC - in response to Message 132073.

                                                                          Last modified: 10 Jul 2014 6:35:59 UTC

                                                                          .... to get a better understanding of the new code in the heterogeneous environment of Einstein@Home ....

                                                                          Yes. Experience has shown the ability of the E@H milieu to step upon the mines in the field. :-)

                                                                          Cheers, Mike.
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                                                                          Message 132402 - Posted 23 Jul 2014 9:47:40 UTC - in response to Message 132073.

                                                                            Another update: still under heavy discussion and thus quite preliminary, but it currently looks like after the current S6CasA "directed" run we will squeeze in a short (1-2 month) run where we will follow-up a few (million) candidates from the S6Bucket runs. The remaining ~45d S6CasA look a bit tight to set one up, but essentially we would just need a new workunit generator - data, application, validator etc. are still there from the original run. At least a follow-up run would fit much better in now than interrupting or having to wait for the end of the next "science run".

                                                                            BM

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                                                                            This material is based upon work supported by the National Science Foundation (NSF) under Grants PHY-1104902, PHY-1104617 and PHY-1105572 and by the Max Planck Gesellschaft (MPG). Any opinions, findings, and conclusions or recommendations expressed in this material are those of the investigators and do not necessarily reflect the views of the NSF or the MPG.

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