Topics

• BYU images, plots
• beam patterns
• sensitivity maps
• yfactor plots
  
• 25-29aug13: x102 calibration runs:
  
• 30jul13: scans across the moon using ao19 and lbw. Shows Tsys ao19.
  
• 03aug13. yfactor, sefd, and ratios on J0603+219 for 1400 and 1665 MHz
  
• 01,03aug13: yfactors on moon with and without the tertiary skirt.
• 02,03,04aug13: yfactors, SEFD vs frequency.
  

• plot sefd vs Ae/Tsys (.ps) (.pdf)
  
• ip addresses
• arduino cal ctrl
• Equipment,receiver weights
• byu documentation
• What we did:
  
• summary of each day
• Details for each day
• previous phased array run: byu19 jun/aug 2010
• Places to look on disc for info
  

• x101/ao19/  .. has memos notes from prior to aug13 observation.
  
• x101/projects/ao19/    copied by projects/byu/..
• has byuazza, and some idl code.
• /share/obs4/usr/x101/src/*ao19*  .. has command files and program logs.
• /share/olcor/corfile.xxx   has interim cor data when connected to ao port. also has time, az,za for some patterns when byu system connected.
• log files for byuazza.log  was in /tmp/byuazza.log on megs3.. but it got rebooted before i moved the file so we lost this.
  

Pre installation:

• 27jun13: system layout on floor (.pdf)
  
• 20jun13: weight being added to the turret floor
  
• 05jun13: draft schedule for jul13 (.pdf)
  
• 05jun13: gant chart for jul13 tests (.pdf)
• 20mar13: ao19 mount on turret floor (.pdf)
  

Sources:  (top)

• Sources Table of some stronger sources
  
• Complete source list. ra,dec, flux as well as rise, set times

• catalog codes:
• N nvss.
•  flux is at 1400 MHz,
  
• coordinates are J2000
• maj,min are major minor axis in asecs
  
• C
•  ao calibrator file .
  
• flux is at 1600 MHz
• The source name links are nvss images of the source at 1405 MHz.
• The images are +/- 7.5 amin, ra increases to left , dec increases up
  

at least a double...
16 51 11.70 +04 59 19.0 23Jy
16 51  3.85 +04 59 41.9 11.1 Jy
16 51  4.94 +04 59 42.3  8.5 Jy

Source ra,dec, flux and AST rise times  (top)

• ra,dec for sources
• Shows the ra,dec JcoordinateSystem  flux(Jy) and comments for sources to use. The is normally at 1400MHz unless otherwise specified in the comments
• AST rise times for source (jul13 run) (.txt)
• Shows the AST (local arecibo) rise time ,and tracking time (minutes)  for the sources (using za=19.69 degrees.)
• The moon is at the bottom of the list. It has a rise,set time for each day (since it changes.)
• jpl horizons output for the when the moon is up at arecibo for the 26jul13->03aug13 (.txt)
• This was used to create the moon rise,set times. The time accuracy is 2 minutes.
• Note: the moon does not rise above el=70deg on 25jul13.
  
• Arecibo tracking time by declination (.pdf)
  

Ip addresses  (top)

The ip addresses, gateways to use:

• 192.65.176.1. observer computer in wapp room.Online Gateway for all byu/ao19  devices to use.
• Will enable them to talk to the cor online datatking computer
• 192.160.174.7  cor online datataking computer (in wapp room)
• This sends command to byuhost and the ao19 cal control.
  
• 192.65.176.160: byu host in transmitter room in dome
  
• listens on port 5010. cor computer will talk to it
  
• Will take to cor computer at : 192.160.174.7
• It is connected via a 1 gigabit link to doJ1331+305 133108.29  303032.96  j  14.5                3C286
  wnstairs.
  
• will the observer gateway be a problem for the high speed data xfer?
• 192.65.176.161: ao19gpib . this is the gpib computer in Cornell rack on rotary floor.
• It is used for monitoring of dewar info. Not needed for data acquistion.
  
• 192.65.176.162: ao19cal    . controls which dipole cal is enabled.
• Receives commands from cor.

arduino cal ctrl  (top)

    There is a cal multiplexor in the Cornell rack on the rotary floor. It selects which dipole will receiver the cal rf signal (from the noise diode)

• Luis's instructions on using the arduino cal (.pdf)
• Mapping digital outputs to caldipoles (.jpeg)
  
• 0 is the input
• 1-19 are the dipoles, 20 is spare

byu documentation

• richard's byu documentation (.pdf)
  

20jun13 weight on rotary floor  (top)

    The weights on the turret floor for the jul13 experiment are:

    So we will be adding 102 lbs extra to the floor.

Other:

•  byu rack in transmitter room: 683  lbs  (no cables included). weighed in transmitter room
  
•  maybe 50lbs for cables
• 57" high (with castors), 21" wide, 35.75" deep
  
• 30amp circuit into box,. single phase.
  

Results: 

BYU plots/images (top)

• Updated to 30oct13 version of images.
  
• Beam patterns:
• 15x15 grids:
• 26jul13 J2123+250 @ 1400.0977
• polA (.pdf)
• polB (.pdf)
• polA + polB (.pdf)
• 28jul13 J2014+235 @ 1399.6094
• polA (.pdf)
• polB (.pdf)
• polA + polB (.pdf)
• 02aug13 J1330+251 @ 1394.8242
  
• polA (.pdf)
• polB (.pdf)
• polA + polB (.pdf)
  
• 31x31 grids
• 02aug13 J2014+235 @ 1664.707
• polA (.pdf)
• polB (.pdf)
• polA + polB (.pdf)
• 02aug13 J2232+117 @ 1399.707
• polA (.pdf)
• polB (.pdf)
• polA + polB (.pdf)
  
• sensitivity grids:
• 26aug13: J2123+250 15x15 (.pdf)   this is german's version with the dipole positions layed out over the grid.
  
• 16 sensitivity grids (.pdf)
• sent 30oct13
  
• Some of the grids compare using the before and after map noise fields.
• 
  

• Page	date	grid	noise	zaoff	freq	src	flux	obs/comments
  1	26jul13	15 x15	before	12.2	1400.1-1409.9	J2123+250	10.34	1,2 same map different offs.
  2			after	6.8	1400.1-1409.9
  3	28jul13	15 x15	before	6.0	1399.6-1400.1	J2014+235	13.6
  4			after	12.8	1399.6-1400.1
  5	30jul13	15 x15	before	9.3	1392.5-1397.4	J0318+164	7.7
  6			after	18.2	1392.5-1397.4
  7	30jul13	15 x15	before	13.7	1392.5-1397.4	J2232+117	7.2
  8			after	7.5	1392.5-1397.4
  9	02aug13	15 x15	before	14,7	1392.5-1397.4	J1330+251	7.0
  10			after	8.3	1392.5-1397.4
  11	02aug13	15 x15	before	8.5	1662.4-1667.2	J1845+098	4.16
  12			after	10.5	1662.4-1667.2
  13	02aug13	31x31	before	16.9	1401.3-1402.2	J2232+117	7.2	finished 04aug13
  14			after	12.3	1399.3-1402.2			finished 04aug13
  15	02aug13	31x31	before	13.8	1665.3-1667.2	J2014+235	13.6	finished 04aug13
  16			after	6.8	1662.4-1667.2			finished 04aug13

  
  
• yfactors:
• moon:
  
• 01aug13: 1392.8711 MHz (.pdf)
• Power on,off and on/off
  
• filename:yfactors_08_01_2013_moon.pdf
• 02aug13: 1392.8711 MHz (.pdf)
  
• filename: yfactors_08_02_2013_morning_moon_overflow_1a14b16a16b.pdf
  
• 03aug13: 1397.7539 MHz (.pdf)
• filename: yfactors_08_03_2013_morning_moon_onoff_1440MHz.pdf
• 03aug13: 1665 MHz (.pdf)
• Plot label says 1397.7539 MHz.. I think this is wrong.
  
• filename: yfactors_08_03_2013_morning_moon_onoff_1665MHz.pdf
  
• 03aug13: 1400 and 1665 remove dead elements (.pdf)
• Just plot on/off.
  
• The plots overplots data from the above to plots.. but does not include dead dipoles
• include the azStep and zaStep measurements taken at 1400 and 1665 MHz
• Plots says that it has averaged over frequency
  
• filename:yfactors_Moon_130803_noDeadElem.pdf
• 03aug13: yfactors formed beams on moon (@ 1665 MHz)
  
• Note: these are actually (YF- 1) (on-off)/off
  
• 15x15 using 02aug13 J1330+251 grid
• polA (.pdf)
  
• polB (.pdf)
• max PolA,PolB (.pdf)
• 31x31 using 02aug13 J2014+235
• PolA (.pdf)
• PolB (.pdf)
• max(polA,polB) (.pdf)
  
• Sources:
• 02aug13: B1843+098 (J1845+097) @1665MHz (.pdf)
• The plots only show on,off difference for beam 1. Looking at the logfiles, we did an on,off for beam 1.
  
• The plot label says 1397.7539.. but i think this was 1665 MHz?
• file: yfactors_08_02_2013_eve_yfactors_4p16Jy_1665MHz.pdf

25-29jul13:Calibration run results: (top)

    x102 calibration scans were done using ao19. The cal never worked so there is no Gain or Tsys value. We tried various setups:

• 25aug13 - Search for best turret position:
• data taken with turret positions 161.74 and 161.40.
  
• 26aug13 - Verify data with "best" turret position (161.60)
• 27aug13 - Take data with dewar 1" below focus
• 29aug13 - Take data with dewar back in normal focus position.l
  

    The plots show the calibration results (.ps) (.pdf)

• Page1: SEFD, beamwidths, sidelobe height using all thedata.
• Top: SEFD in Jy
• Middle: the beam width in Arc seconds
• red: za beam width
• green: azimuth beam width
• colored (center symbols) average beam width
• Note that he azimuth beam width does not increase with za while the za beamwidth does (because of the za spillover).
  
• Bottom: average 1st side lobe height.
• Page2: compare calibration while  in focus and 1 inch out of focus.
• The red symbols show data taken on 27aug13 while the dewar was 1 inch below the nominal focus.
• There is not much change in the results ... maybe a slight rise in sefd,bmwidth at za=12,13.
• Page 3: pointing error using all the data
• This includes the data on 25aug13 when the turret was not in the final position.
• the rms error is 5.36 ,8.34 asecs (za,az) is small compared to the beam size.
• Page 4: pointing error using data taken in the "best" turret position (161.6).
• the turret was moved so that the mean azimuth error  went to 0.

summary:

• The sefd is about 14 Jy using dipole 1 and the ao system
• The average beamwidth is about 190 Arcsecs
• The average level of the first sidelobe is -14 db
• The pointing error was small
• moving the feed 1 inch down in focus did not change the pointing or sefd very much.
  

30jul13: scans across the moon with ao19 and lbw using ao system. (top)

    On 30jul13 scans were done across the moon. Data was taken at 1400 MHz.

• Scan 1: ao19 dipole 1 using ao system.
• start 1 deg off moon  (in za), drive on, off , and then back on.
• Scan2: ao19 dipole 1 using ao system
•  scan across the moon (in za direction) then come back
• Scan3: lbw  using ao system with linear polarization.
  
• do cal on,off 1 degree off moon (in za direction)
• drive across the moon and then come back
• Use cal to put data in degrees kelvin
• Use measured cal deflection in degK to put ao19 scans in deg K.

• Page 1: scanning across the moon using AO19 with AO system
• Top frame:scan1:  total power vs time .
  
• Black is polA, red is polB.
  
• The data has been normalized to Tsys off the moon .. so this show TonMoon/ToffMoon.
• The ratio is 2.6 polA, 2.7  polB
• 2nd frame: scan1: total power (degK) vs distance from the moon center.
• The distance from the moon was computed using the az,za encoder values (after model removed)  and the ephemeris file az,za ,
• The data was scaled to degK using the (moon-sky) deflection measured with lbw (193.1K ..see page 2).
• TsysA is 111.5, tsysB is 122.0 K
• Note:
• Off moon Tsys=(Trcv + Tspill + Tsky)
• on moon Tsys=(Trcv  + Tspill + Tmoon)
• OnMoon - Offmoon = Tmoon - Tsky
• Tsky  is typically 6K at 1400 MHz (as long as you're not in the plane).
• 3rd frame:scan2: total power vs time
• german changed the lna bias voltage to 3.05 Volts before this run
• bottom frame: scan 2: total power (degK) vs distance from moon center.
• TsysA=112.6, tsysB=119.1
• TsysA went up a little, tsysB went down.
  
• It looks like there is some polarized power coming off the moon scan. The scan1,2 change may be from the change in the parallactic angle.
• Page 2: scan across the moon with lbw
• A cal scan was taken 1 deg off the moon. It was then used to convert all of the lbw data to degK.
• Top frame: total power (degK) vs time as we scanned across the moon.
• 2nd frame: total power (degK) vs distance from center of the moon.
• tsys off the moon was: polA 30.7K , polB 31.3K
• The average (Tmoon - Tsky) = 193.1 K
• 3rd frame: Over plot lbw scan with 2nd ao19 scan
• bottom frame: Over plot lbw scan with ao19 scan2 after removing Tsys off moon.
• This shows the shape difference for the two scans. lbw has a sharper drop when moving off the moon than ao19.

Summary:

• Tmoon - Tsky was measured to be 193.1 K at 1400 MHz
  
• Tsky is about 5-6K so Tmoon is probably close to 200K
• This is smaller than the values don found in the literature.
• AO19 Tsys  112 polA, 120 polB. Some of this difference may be from the polarized power off the moon.
• The MoonOn/MoonOff ratio was polA 2.6, polB 2.7. This compares with what by measured on 03aug13.
  
• The ao19 beam has a slower drop off than lbw.
• The beam width of ao19 is narrow than lbw (190 vs 200 asecs), but the average sidelobe height of ao19 is larger (-14 vs -16 db).
• There is very little change in power .6 deg degrees off the moon center. So our 1 deg offs are probably not being contaminated by the moon.
  

processing: x101/projects/ao19/procdata/moon30.pro

03aug13: yfactors, sefd @ 1400 & 1665MHz (top)

    On 03aug13 on,offs were done on source J0603+219 (B0600+219):

• The source flux is:
• 1400 MHz: 2.69 Jy
• 1665 MHz: 2.44 Jy
  
• The off was 1.5 deg away in azimuth
• dipole 1 was used. with the byu system and with the ao system.
  
• Data was taken at 1400MHz and 1665 MHz.

• Page 1: Yfactor, sefd's
  
• top:  yfactor (on/off) dipole 1 . plotted vs frequency.
  
• Purple : AO system ratios
• Blue   : byu unformed be
• triangles: polA, * polB
• red    : byu formed beam
• Bottom: sefd vs frequency
• 1665 has a lower sefd (4-9) than 1400 MHz (7-12)
• polA has a lower sefd than polB (except for ao 1400 MHz)
• Page 2: ratios of yfactors and sefd's
• This shows the ratios of:
• formed beam/unformed beam
• byu Unformed beam/ ao unformed beam.
• You can see how things improved as you move from 1400 to 1665.
  
• Top: ratios of  yfactors:
• Larger yfactors are better. ratio > 1 --> numerator is better.
  
• red: byu formed beam/ byu unformed beam
• Blue:  Byu Unformed Beam/ AO (unformed) beam
  
• Botom: Ratios of SEFD
• Smaller SEFD'S are better : ratio < 1 --> numerator is better
  

SUMMARY:

    The table shows the yfactor and sefd results.

processing: x101/130803/ao19.pro

03aug13: Byu system: yfactors, Tsys on moon. (top)

 
  We did on/offs on the moon at 1400 and 1665 MHz with the byu system. The yfactor was then computed for each beam. 

The plots shows jay's yfactors with bad beams removed (.pdf)

The second plot showsTsys for various moon yfactors (.ps) (.pdf)

• Black is Treceiver + Tspillover
• Red is Treceiver + Tspillover + Tsky
• Tsky was set to 6 K
• The top plot uses Tmoon = 200 K
• This is the value measured with lbw on 30jul13.
  
• the bottom plot used Tmoon=220 K

01,03aug13: Yfactors, tertiary skirt, moon, Ao system.  (top)

    Moon on,offs were done using the ao system :

• 01aug13:  1400 MHz, screen not on the tertiary
• We did a single on , off stepping in azimuth
  
• 03aug13: 1400, 1665 MHz screen on the tertiary.
• For each frequency we stepped off in azimuth and in za.
  

• Top: 1400 MHz   yfactors vs frequency
  
• Skirt on: black,green polA, red, blue polB
• skirt off: purple,dark red
• Looks like there is a small slope in yfactor vs frequency at 1400 MHz.
  
• The Tsys values printed assum Tmoon=200K, Tsky=6k (these were measured 30jul13 with lbw)
  
• middle: 1665 yfactors
• Skirt on: black,green polA, red, blue polB
• No tsys values are listed since we didn't measure Tmoon at 1665 MHz.
  
• Bottom: 1400 MHz ratio YfactorScreenOn/YfactorScreenoff
• The ratio was about 1.04

SUMMARY:

• The azimuth and za steps gave close results
• PolB is worse than polA  at 1400 MHz and 1600 MHz
• The tertiary skirt decreases the spillover. Tspill occurs in both the numerator and Denominator of Yf:
• Yf=(on/off) = (Tmoon  + Trcv + Tspill)/(Tsky + Trcv + Tspill).
  
• The skirt increased the yfactor by  4%.
• Assuming Tmoon=200, Tsky=6 K, Tsys decreased by  about 6%.
  

02,03,04aug13: yfactor, SEFD vs frequency (top)

    Frequency scans were done on 02,03,04 aug13 to measure the yfactor and SEFD vs frequency using the ao system. The setup was:

• Use the interim correlator.covering 100 MHz (4x25MHz) per integration. There were 1024 channels across each 25 MHz.
  
• Do 5 freq integrations centered at: 1250,1350,1450,1550,1650 MHz
• At each frequency do a 1 minute position  switch (1 minute on, 1 minute off).
• The sources used were:
• J1330+251  za =7.0 deg
  
• B0600+219 za=4.6 deg
• B2128+048 za=14.4 deg
• On/Off was computed for each source
• The flux vs frequency was divided into  (on-off)/off to normalize the Yfactors to a 1 Jy source
• On/Off for B2128+048 was increased by .01 to compensate for the higher tsys (the za was higher)

• Page 1: On/off vs frequency for polA and polB.
• the bottom plot shows the source flux vs frequency for each source.
• Page 2: Normalize (on-off)/off  to a 1 Jy source
• frame 1,2: normalized on/off to 1 Jy.
  
• The green trace (B2128+048) shows a lower value (because of the higher za).
• frame 3,4: overplot on/off after correcting B2128+048 by .01.
• Page 3:Average On/Off and SEFD vs frequency.
• The on/off and SEFD for the 3 sources were averaged and then plotted.
• 40 channels at both edges of each 25 MHz bandpass were not plotted. The filter falloff was causing some unwanted structure..

SUMMARY:

• The SEFD ranges between 17 Jy and 7 Jy between 1200 and 1700 MHz
• SEFD for pol B is generally higher then polA
• at 1650 MHz SEFD polB is 25 % higher than PolA
  
• at 1400 MHz the sefd's for polA and polB are pretty close.
• We may be seeing some resonances.
• around 1515 MHz?
• The 25 MHz band around 1330 MHz was wiped out by the punta   Borinquen radar.

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