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: http://www.atnf.csiro.au/research/pulsar/array/index.php?n=Main.Minutes2011
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Minutes2011 23rd Nov 2011The meeting summary as follows: 1. Please check the project page and, for each project that you are leading, please let George know a suitable date at which point you would be willing to give a talk at the PPTA meeting. George will use these "review dates" as a method for selecting talks at the meeting. 2. Dick discussed three documents that he had sent around by email that relate to the IPTA. Please read and comment (by sending Dick an email) on the documents by Dec 7th. The next IPTA steering committee meeting will be on Dec 8th. A few misleading statements in the documents were identified and Dick will update these. 3. Mike suggested the inclusion of three new HITRU pulsars into the PPTA. They have the following properties: - 3.5 ms period. s/n ~ 40 in 10 minutes, narrow width, sharp edge. Current timing at 1.5us. DM ~ 60 cm-3pc. Don't know what it looks like at other frequencies. 6-d orbit - white dwarf companion. Name: J1546-45. - J1446 - gamma ray, high Edot pulsar, black-widow mass companion. Timing may not be so good. 2.2ms. Narrow pulse. - 2.0ms, weaker. It was pointed out that choosing whether they should be included and other pulsars removed is a complex problem that needs careful thinking. For now, they will be added into the PPTA schedule and listed as "low priority". A review of the PPTA pulsars will be led by Mike and completed by April 2012 (before the next round of proposals). For the next proposal (in Dec) we will request a little extra time for the project. 9th Nov 2012During the PPTA meeting today we agreed/discussed: 1. Having a shorter meeting more regularly. The plan is to have a 45 minute meeting every Wednesday from 12:30. 2. We will continue to use the MeetingPlace telecon system (i.e., everybody phones in). At some stage in the future we will trial other web-based systems (we noted that 'google' doesn't work in China and 'skype' is having more dropouts) The following talks were given: Ryan Shannon: PPTA_limit_rms.pdf Described method to limit the GWB. Choice of weighting function needs discussion. 1909 is the best pulsar in the array for getting a limit. Followed by 1713 then 1857 then 1744 then 0437. The limit gets worse after a while and that's because of the weighting for each pulsar. 1857 includes the Kaspi data. A(95%) ~< 3x10^-15. Data sets includes the data release + Joris data. Dick Manchester: DRAO_psrs.pdf Devloped by Tom Landecker and Maik Wolleben. 300-900 MHz with stop-band 500-640MHz. Use PDFB3 as backend. Observations on 7 Nov and 8-9 Nov by JR/RNM/Aidan. Haven't processed the polarisation data yet. Observations with this system for a few pulsars are presented in Dick's talk Mike Keith: mkeith_dm_ppta_nov11.pdf Talk demonstrated new method for removing DM variations (without removing GW signals). A paper on this topic will use PPTA data release 1 data set. Will describe method. Show example plots to show that previous methods are not as good. WIll measure DMs and show structure functions - compare with Xiaopeng. Include discussion on how important ISM effects are for the PPTA in the future (and issues for wide-band systems etc.). Dick suggests looking at timing from the lowest frequency data set Bill also suggests including how to choose which pulsars actually get worse with the DM correction. Please send suggestions for the next meeting. With the reduced time we will probably have time for 1 news item and 1 science talk. 7th Sept 2011Unfortunately, it was quite hard to take minutes today as we had a few issues with skype, but here is my memory of the meeting (please feel free to add any extra comments if I've missed something). Observing: we agreed that everyone will look at the observing schedule and start to enter when they can observe into the observing roster. GH discussed future ideas for Parkes to be operated remotely and asked for volunteers to help test any proposed remote observing systems. Mike Keith, Willem van Straten and Sarah B-S are willing to help out. Note: in the foreseeable future there is no plan to lower the restriction for "two-people at Parkes". Testing the remote systems will therefore be an increased work-load for us -- we still need two people in Parkes and extra people to trial the remote observing. Sarah: Mentioned her discussions with Massimo Tinto. We suggested that he may like to present a talk on his ideas at a future PPTA meeting. Emily Petroff: Discussed her work in trying to detect/limit gravitational wave burst sources of arbitrary functional form. The main issue currently being determining a suitable detection statistic for a burst. Xiaopeng You: Discussed his work in measuring/modelling rotation measure variations caused by the Solar Wind. He also presented work on using pulsars as a space-craft navigational device. Daniel Yardley: Described his plans for implementing the Cholesky method into his detection scheme for a gravitational wave background. All their talks/figures are online. Papers: Everyone is requested to send me a brief outline of the papers that they're currently working on. I'll collate this list and make it available for the team. |