Telescope and Datataking status 2010 Visiting Committee Meeting

Telescope and Datataking status 2010 Visiting Committee Meeting Phil Perillat NAIC AUSAC Meeting – April 19 -20, 2010

Talk Outline • Telescope performance – – – • Datataking: – – • Backends Commensal observing Future – – • Pointing Gain/Sefd/Tsys: cband, lband, 800 Mhz New telescope observing limitations Backends 12 meter Summary Online: http: //www. naic. edu/~phil/talks. html apr 10 vc 10 NAIC AUSAC Meeting – April 19 -20, 2010

Pointing • Pointing model made dec 07/jan 08 after painting shutdown. Date Az Err (arcsec) Za Err (arcsec) Total Err (arcsec) 2003 mod 14 5. 38 3. 48 6. 41 2004 mod 15 4. 20 2. 41 4. 84 2007 mod 17 4. 39 2. 99 5. 31 Jul 08 -feb 09 6. 8 4. 6 8. 2 Mar 09 -jan 10 6. 3 4. 9 8. 0 Mar 10 -> 10. 6 9. 0 13. 9 NAIC AUSAC Meeting – April 19 -20, 2010

Pointing Errors: mar 09 -mar 10 • Mar 09 -jan 10 data before break – Errs vs za – Errs vs az (1 az term y 08 -09 removed in model) • Mar 10: after beam repair: – Errs vs za (limits: 3. 5 to 12 deg za) – Errs vs az (looks like 1 az term. . ) • Rms. Error: – Before break: 4. 9, 6. 3 (za, az). Tot: 8. 0 asecs – After break: 9. 0, 10. 6 (za, az). Tot: 13. 9 asecs NAIC AUSAC Meeting – April 19 -20, 2010

Gain, SEFD, Tsys: lband, cband • • Data mar 09 - mar 10 Lband @ 1400 Mhz Cband @ 5000 Mhz Gain K/Jy Gain Tsys K Tsys Sefd SEFD Beam width bm. Width NAIC AUSAC Meeting – April 19 -20, 2010 Lband Cband 1400 5000 11. 3 8. 2 28 K 27 K 2. 5 Jy 3. 3 Jy 202” 56”

700 -800 Mhz rcvr • Installed jul to dec 09. penn state feed – Cooled to 70 K, cavity filter in front of lna. – Gain, Tsys: Tsys high. . Cavity filter, over illuminates tertiary. – Sefd , Beam. Width – Rfi: Chn 67 (879 Mhz) LP tv. • Helped buy parts for lp dtv so they would go off the air • BYU single pol rcvr 5% smaller bm width – Still working on dual pol mode. • Running out of time for clean band: – Emg services: 763 -775, 793 -805 ready to go. NAIC AUSAC Meeting – April 19 -20, 2010

Alfa • Alfa tsys measured during survey runs: – 4048 measurements mar 09 thru mar 10. – Each color is a different project: • White: A 2010 (alfalfa), Red: A 2048(ages), Green: A 2433(auds), Blue: (A 2453) – Pol. A on left, pol. B on right. – Beams 0 -3 – Beams 4 -6 – Beam 2 a has unstable Tsys. NAIC AUSAC Meeting – April 19 -20, 2010

observing limitations • The weights and distances on az arm. – Za for dome center of mass: 1. 9 deg below optic axis za – Ratio Dome. Weight/Ch. Weight = 6. • For constant moment arm: dza. Ch = 6*dza. Dome. • How we observe: – Ch sits at 8. 8 degrees, dome moves in za. – Azarm imbalance changes with dome za. – Elevation rails shimmed high so imbalance tilts receiver in dome, onto the paraxial surface. – 3 tiedowns keep the average platform height fixed with temperature (no tilting of platform done by td’s) NAIC AUSAC Meeting – April 19 -20, 2010

The problem: • Max allowed imbalance: 15000 kip-ft – Various configs for ch, dome motion: • BUT: max allowed imbalance depends on td tension – Td tension relieves tension in beams. • Td tension used to keep avg platform height in focus. – This is a function of temperature since main cables change length with temp. • Examples showing za range vs temp: – Dome tracks: Ch at stow: normal astronomy – Dome tracks: Ch tracks dome above 8. 8 deg za – Dome tracks: Ch at 0 (aeronomy az swings). NAIC AUSAC Meeting – April 19 -20, 2010

What we can do: • Removing weight from the dome – decreases the unbalanced moment arm • Removing weight from the platform – Allows more tension in the tiedowns • Installing the tertiary motor drives. – Lets you make the optical axis longer – This lets you increase the td tension (pull down on platform) to get back in focus. • 1 platform inch is 2 -3 kips per corner • 1 deg F is. 75 kips per corner. NAIC AUSAC Meeting – April 19 -20, 2010

Datataking: Backends Device Interim cor Type/bits # device Cor: 3/9 lvl 4 Bw MHz Pols 50 4 Wapps Cor: 3/9 lvl 8 100 4 Gal. Spect Pfb/fft: 8 8 2 Mock Pfb/fft: 12 2*7*2=28 172 4 Daeron Smp: 14 1 or 2 10, 5 1 Pfs smp: 2 -4 1 20 1 RI Smp: 1 -12 2 10 2 2 NAIC AUSAC Meeting – April 19 -20, 2010

Datataking: new functionality • Mock single pixel observing – 7 x 172 Mhz covers 1 Ghz IF with 20 Khz res. • 1 Ghz, 10 Khz res. Possible with 2 nd 7 x 172 set – Different settings allowed for 7 bands: • Center freq, channels, bw, config: sum. Pols, 2 pol, stokes. • Mock file server upgrade: – 3. 2 -> 5. 5 Tb/server. Total. Disk: 14*5. 5=70 Tb online. • Mock aeronomy sampling system – 6 bands: 32 Mhz widest, samples @160 Mhz – Example: 10 sec clp spectra (ch) NAIC AUSAC Meeting – April 19 -20, 2010

Datataking: Commensal • Survey names: • Alfalfa extragalactic search, short • Routine survey commensal observing: integrations, large area • Ages • Example: – extragalactic search, median integration Primary Com 1 Com 2 • Auds – extra galactic search: long integration • Igalfa/galfacts/zoa, rrl: may 09 -sep 09 56 3 hour sessions alfalfa/wapp Togs/galspect Palfa/mock 1* • • Zoa : zone of avoidance Igalfa- galactic survey galspect, Ages/mock 1 Togs/galspect • • Galfacts: mock, full stokes, 300 survey Galfacts: galactic polarization Mhz Bw. Palfa/mock 1 Zoa, rrl/mock 2 • Rrl: recombination line survey 4 Tb/night • 65 Mb/sec =455 Mb/sec, Galfacts/mock 1 *7 Zoa/mock 2 • • Togs- galactic survey Zoa/rrl: mock 2, Galfacts/mock 1 Zoa/rrl/mock 2 Igalfa/galspect 300 Mhz Bw, . 1 sec integrations. • Palfa: pulsar search. Meeting – April 19 -20, 2010 NAIC AUSAC

Future: Backends • Vlbi: Digital Back. End: dbe – 2: 1 for 305 meter, 1 for 12 meter – Has mode to run 500 Mhz bw spectra • Aeronomy – Integrate mock device with datataking. • Planetary radar with mock: – Needs fgpa programming (or use regular baseband sampling with pdev). NAIC AUSAC Meeting – April 19 -20, 2010

Future: Backends • Mock single pixel Baseband sampling: – – Need to add functionality to cima Work on pdev headers. 7 or 14 boxes. . Bits Bandwith per box: 4 8 16 NAIC AUSAC Meeting – April 19 -20, 2010 1 pol Mhz 70 35 17. 5 2 pol Mhz 35 17. 5 8. 75

Future: 12 meter • 12 meter telescope – Integrate with vlbi station observing using dbe – Allow non vlbi usage of telescope with 305 m • Needs pointing program • IF signal needs to be piped into standard backends. • Software to support it. NAIC AUSAC Meeting – April 19 -20, 2010

Summary • Telescope performance: – Pointing: • rms. Error: za: 9. 0 az: 10. 6 tot: 13. 9 asecs • Need to fix 1 az term from tilted platform – Gain, Tsys, sefd, Tsys • Sefd: 800: 13. Jy, lbw: 2. 5 Jy, Cband : 3. 3 Jy – Get 800 antenna replaced • Tsys alfa 26 -35 K (vs za). fix bm 2 a. – Limitations: • Za 3. 5 ->12, daytime fixed position. • Future: – 12 meter integration. – Backends: • Integrate aeronomy, do planetary radar, mock baseband sampling. NAIC AUSAC Meeting – April 19 -20, 2010