SUG Minutes – 10 Nov, 2015
In attendance
Jim T, B, S, Chuck, Shing, Francisco, Whit, Tom, Dave, Andy, Dick
Station Reports – New Info in RED
Whit – Still 200 Kk background
Tom – Still making great observations with the FSX-4 and a Jove dual-dipole array.
Jim B –New array of 4 LWA style antennas is on the air – testing underway. The FSX-2 and an RTL-SDR are operating. Jim has also started a new, fancy, nice-looking web site for HNRAO.
Dave – Now has an automatic calibrator system—a modification of the FS-200 calibrator system—running step calibrations once a day. All else pretty much the same at AJ4CO.
Chuck – Spectrograph FSX-6 has been installed on MTSU campus and was operated for the first time. A square Jove array will be used initially. A bowtie LWA-style antenna array (one or two crosses) will then be built with a design similar to Jim B’s array. We have borrowed the calibration system from Dave and are doing a calibration on the FSX-6 spectrograph in switching mode.
Francisco – Will operate narrow band (20 MHz) polarimeter and two Jove receivers at home. This system is nearing completion. Rosemary hill installation of FSX spectrograph and TFD dual pol antenna coming soon.
Andy – operating FSX-3 instrument from home using Jove dual dipoles and currently working to get high speed internet connectivity.
All observers are urged to keep an engineering log and update their system drawings for the SUG site. Dave, Jim Brown, and Dick have been working on a system drawing format which will serve as a guide for others preparing SUG system diagrams.
Discussion – New Info in RED
Start of the 2015-16 Season – Jupiter’s elongation will be 60° on 11 Nov 2015.
JUNO Ground-Based Observing Campaign – Dave will prepare – with everyone’s help – a document of SUG instrumentation capabilities which may be shared with Philippe Zarka who is coordinating ground based observations during the Juno mission. The draft SUG capabilities document is being prepared. AJ4CO documentation updated and work underway on HNRAO diagram. Document of instrumentation capabilities being prepared, and anticipated to be available before the next SUG telecon.
Speaking of JUNO – congratulations to Chuck and his LWA team in obtaining over 100 hours of observing time to support the JUNO mission.
SUG Science – At present, the following are thought to be achievable with data from participating SUG stations.
1) CML-Io phase plane probability distributions – what does the phase plane look like for different emission types and polarizations?
2) Modulation lane studies – do modulation lanes appear the same for spaced spectrographs?
3) Ionospheric scintillation comparison
4) Jovian DAM flux density calculation
5) Polarimetry – what is the RCP to LCP power ratio for a given Jovian DAM observation?
6) Spaced Spectrograph comparison – may be possible to get an idea of emission source beam shape or cone wall width by comparing spaced spectro records.
7) Fractal analysis – may be interesting to investigate what is actually required to attempt such analyses.
8) Shing suggested that Jupiter signals may be useful as a way to probe CMEs. Flagg commented that there was a study done years ago showing a correlation between the scintillation frequencies in Jovian L-bursts and Jupiter’s elongation from the sun. (with help from Francisco – looking for reference)
RSS Versions in Use – Tom 2.2.25; Wes 2.1.20; Jim B 2.6.0 & 2.6.1; Dave 2.1.19 (DPS) & 2.1.20 (FS-200) & 2.2.25 (data review). Jim Sky noted that the new switcher-modified FSX spectros should use RSS verion 2.5.3 or higher and that the most recent version of RSS is 2.6.1.
Techno problems – Dave and Jim are having problems with USB to Serial adapters. Whit brought up several ideas including purging old drivers and installing new drivers every time there is an OS upgrade. Whit sent around a couple of relevant links. Jim B shared with everyone a picture of an adapter available from Best Buy that has been working very well for him between a Win 7 computer and the FSX-2. Whit stressed the importance of using latest chipset adapters and updated drivers.
Spectrograph Network – GOOD NEWS – The education proposal submitted by Shing, et al. includes money for 5 years for development of clusters of radio spectrographs. This proposal has been approved however the exact details of funding related to the Jove/SUG portion are not yet available. Funds for equipment, which may be as high as $100k, will be managed by Chuck at MTSU.
1) There are 27 teams competing to receive funds from this grant – results expected early 2016 – with funding start possibly by summer 2016 (Chuck has Oct 1, 2016 as a potential start date).
2) Discussion related to ideal frequency coverage – possible goal is 15-88 MHz but perhaps higher? Shing and Chuck will advise – this will drive much of hardware development. Perhaps include some e-Callisto equipment. Note - lowest amplitude calibrated frequency for solar flux is 245 MHz
3) Discussion of TFD antenna vs LWA type. Suggestion that it would be good to have an LWA antenna and TFD antenna at the same site for comparison.. Dave suggested ways to make less expensive LWA type antennas than Jim B is building.
Noted that log-periodic antennas can be used in VHF and low UHF frequency range and Whit commented on e-Callisto use of such antennas. LWA antenna is good up to 100 MHz.
4) Shing and Chuck will create a development plan with some levels of detail for such things as educational program aspects, desirable system specifications (such as frequency range to be covered), optimum cluster station locations and spacings, and perhaps a scheduling guideline for planning how to implement the project and get an experimental beta cluster on the air in 2016. Some of these ideas began to come together during our recent wide ranging group discussion. We are currently at the “what we would ideally like to have” part of the discussion as relates to measurement capability. Funding will of course ultimately drive what is possible in terms of the hardware available to meet the science and educational goals of the project. The SUG Instrumentation Capabilities Document that Dave is working on may serve as the basis for planning what we are able to accomplish for Juno support and as a starting point for analyzing what may be possible with the new Shing funding.
5) Tom suggested looking at available and archived data from existing SUG stations to determine what science can be done with these observations. This is an important point and should probably be at the top level of current program planning.
6) Shing mentioned an August 2017 eclipse that will be visible over eastern USA - what should we plan for in this regard? It seems obvious that this event is worth observing with as many spectrographs as possible. Not sure what may be seen, but I sort of recall that Chuck promised to buy a beer for all SUG observers who capture a solar burst during the eclipse.
7) Shing has previously suggested that the JOVE/SUG join the ISWI. Shing explained a bit of background of ISWI program and UN sponsorship. Applying to be included as part of this program (an ISWI instrument) may benefit SUG in terms of future funding and collaboration with other instrument and science groups.
8) Discussion of different types of spectrograph instruments (SDR and swept frequency). Shing suggested ideal goal is to measure dual polarization with coherent instruments capable of recording both phase and amplitude. Currently Dave at AJ4CO obs is the only SUG station capable of simultaneous polarization measurements using the DPS. This is a dual polarization spectrograph with a common local oscillator and dual ADCs. The ADCs simultaneously sample their respective detected RCP and LCP signals. Other spectrographs (HNRAO, MTSU, Alachua, RHO) are (or soon will be) of the polarization switching type. This means that the instrument selects one polarization, makes a sweep (over nominally 200 channels in 0.1 seconds), switches to the other polarization, repeats the sweep, then switches back to the first polarization and sweeps again – and so on, switching back and forth for all eternity. RSS software (rev 2.5.3 and above) offers a dual display, with one panel for RCP and one for LCP.
9) Shing described an ideal cluster as having stations aligned along magnetic latitude and longitude with spacings on the order of 10s of km (up to perhaps 100km).
10) Jim S commented that we may not need a full blown computer at each cluster station. Perhaps something like a Raspberry Pi or a shiny new WTF 2016 might work. Shing suggested that data storage on site and recovery once a week might be acceptable.
Spectrograph and SkyPipe Data Archiving – Efforts to make the spectrograph data compliant with the PDS standards continue. Current archiving/listing opportunities exist with the VESPA, VWO, and PDS. Discussion of what pieces of metadata are scientifically desirable took place. Jim Sky sent an email to the SUG participants on 9/15 listing the metadata planned for the SPS files. The only addition to Jim’s list put forward (by Shing) is that one time stamp per sweep would be a good idea, when feasible. This may be interpolated from the starting and ending time stamps currently in use; or, they may be inserted in real time when the GPS-based sweep-start-control system becomes a reality. No subtractions from Jim’s list were put forward.
Shing mentioned that the UN’s ISWI program is trying to cope with the difficulty of asking remote observers to submit data in real time. Shing noted that ISWI is also faced with the issue of how to handle data transfer and archiving.
Calibration – nothing new
Polarization Switching – the campaign to modify the FSX series of spectrographs to switch alternate sweeps between RCP and LCP inputs is in progress with Wes’s FSX-1 spectro presently under the soldering iron.
Time Synchronized Spectrographs – Whit is preparing a paper on timing accuracy and has sent around a paper on an arduino/GPS based high accuracy timing system. Considerable discussion on Whit’s work with time synchronization and a GPS disciplined network time server he has built. Dave is testing one of these units, and reports that he is pleased with the results so far. Andy continues to experiment with GPS timing and mentioned an atomic clock on a chip.
New SDR Developments – Andy is running both an SDR receiver and the FSX machine – comparisons of spectra obtained with the two will be available soon. Jim Brown has comparative data also. Jim Sky now has the AirSpy unit and will try to make it compatible with RSS.
Phase Plane – No news.
Summary Thoughts
The following section is an addition to the minutes of the SUG telecon. I have tried to summarize status of several near term and long range opportunities. Hopefully this will aid in bringing these activities and some outstanding issues into sharper focus.
1. In the relatively near term we have an opportunity to share data thru the French VESPA data archive. This project has been active since the SARA meeting of June 2014. Baptiste has developed file conversion routines to convert RSS data into CDF files so that they can be viewed by the wider scientific community. He has also expressed a willingness to host our data on the VESPA archive machines. Many details remain to be resolved. Is that where our spectro data should be archived? What about the Jove archive – will sending our spectro files to VESPA have a negative impact on the Jove archive? As far as I know we currently have no plans as to how data will be made available from participating SUG stations and transferred to VESPA. Who will participate? Is there a file conversion utility to convert CDF back into RSS so we can view our own archived files?
2. In addition to the data archiving opportunity in VESPA – there is the possibility of actually being recognized as a contributing entity to the network of ground stations being managed by Phillipe Zarka that is supporting JUNO. Our strategy in this regard is to complete the SUG Instrumentation Capabilities Document. If this document is shared with Zarka the result may be that some SUG stations will participate as official JUNO support stations. (AJ4CO with its advanced capabilities has already been so recognized). If we are, or are not, recognized as part of the ground based JUNO network our spectro data can still be made available thru VESPA.
3. Jim Sky is working with the Planetary Data System (PDS) to provide Jove/SUG data to that archive which has strict standards of acceptance. Peer review of the data at some level is required which may mean that this process will not be in place in time for JUNO support – at least in the early months of the mission. These two archiving opportunities (VESPA and PDS) appear to have different standards of acceptance and may in fact have different software requirements. Is the software work Jim Sky is doing for PDS applicable to VESPA? How do we interface with these two archives with the minimum amount of work for individual SUG stations?
4. Shing has delivered a most important opportunity to SUG in the form of grant money that may result in the development of a network of up to 5 clusters of spectrograph stations with 5 stations in each cluster developed over 5 years. We anticipate that we will know how much funding will be available early next year and consequently how much of this concept can become reality.
During the last few SUG telecons we have begun discussing some tentative hardware goals – such as coverage up to 100 (or more practically 88) MHz and dual polarization spectral data. Station clusters may extend over 100 km ideally located along magnetic NS and EW lines. Existing FSX stations may become the core stations of these clusters but it is likely that SDR radios with extended frequency coverage such as the AirSpy will be used to augment our 15-30 MHz coverage.