12 Nov
2012
12 Nov
'12
8:37 p.m.
Notes from Pole from the last few days. Zak writing for Chin Lin, Jamie, Colin, Steff,
Jon
Please forward this on to B2 list as it will probably bounce coming from this USAP
address.
Friday Nov 9th:
Colin arrived the day before with RPS and Uber chopper. Assembled and put up Uber Chopper
for BICEP2. Installation actually went really smoothly given its size.
Chin Lin worked on RPS assembly and leveling.
Saturday Nov 10:
More RPS assembly. Started B2 thermal maps with Uber chopper.
continued thermal maps on Keck with Ze Choppa
First round of Bicep2 data demodulation, tried to get it out on sptr, but turned out we
were blocked for sending too many small files
Sunday Nov 11:
Put RPS on DSL mast!
DSL mast did not have any high guide wires, so we had to become riggers for the day and
rig up some steel cable to level and stabilize the mast. Very successful, we are now
monitoring level with B2 GCP and will estimate level fluctuations due to wind.
Started 3 hour raster style beam map at night to verify the source.
Steff managed to send out the data files from Saturday.
Monday Nov 12:
Turned out the chop ref or pin switch was not working on the overnight beam map. Took RPS
down, debugged lots of components and it ended up being one of the D-cables inside. Fixed
this.
Found chopped source in timestreams, started another raster style map just to verify the
source works. Verified we see the source.
Chin Lin learned how to put files on sptr for Bicep2. There should be Bicep2 data up north
for Randol to analyze.
Tuesday Nov 13(today):
Chin Lin found a problem with B2 uber chopper maps, no demodulated signal. Narrowed it
down to the reference flaking in and out, possibly because we have been messing around so
much by the B2 mount for the RPS. This intermittent problem is still being debugged, but
probably made most of a day worth of beam maps useless. Randol finds the chop speed of the
uber chopper to be too slow (~10 Hz). We are planning to take slower rasters with Bicep2
to make up for the slow chop speed.
Colin tested a short part of an RPS schedule. Part way through, lost communication with
RPS and schedule hung. Colin debugging now. Source is behaving and he can control the
stage, so possibly a network error.
Jon arrived today, said goodbye to Cynthia. Jon doing a cryo fill with Steff, so Chin Lin
and Zak are off the hook except for being backup and support for fills.
Notes on delays and schedule:
1) We were supposed to have finished RPS data taking yesterday. Instead, we havent started
and we figure we need between 7-10 days of data taking to do the ~24 hour schedules for 5
dk angles and to fridge cycle between each measurement.
2) B2 had scheduled moon maps for the 12th to the 15th, but the sun is actually very close
to the moon until the 16th. Instead, we will try to finish thermal maps before the moon
comes up, and do moon maps from the 16th to the 19th. This was the time alloted to RPS
before, but it will not be available for B2 anyway by this time.
3)Keck will prioritize RPS maps for the three receivers that are to come down early, and
continue RPS maps on the other receivers after we have started to warm up. We can catch up
on RPS and Uber chopper maps for RX0 and RX2 in December to try to get RPS on Bicep2
earlier.
4)B2 will probably have to sacrifice some of the week long far sidelobe testing or all of
the slippage time if we are going to try to fit RPS in for them. That would be roughly the
25th-30th of November.
12 Nov
12 Nov
9:17 p.m.
New subject: [keckarray] Pole notes: Nov 13
Hi Zak,
Thanks for the report. Sounds like you guys are working hard.
The uber chopper can be made to chop faster than 10 Hz with more
current--please consider whether you want to push that more. Of course
the point of it is higher S/N, and there is probably little 1/f penalty
between 10 and 18 Hz, so somewhat slower rasters as a way to add more
integration time may be just fine.
Notes on delays and schedule:
1) We were supposed to have finished RPS data taking yesterday. Instead, we havent
started and we figure
we need between 7-10 days of data taking to do the ~24 hour schedules for 5 dk angles and
to fridge
cycle between each measurement.
7-10 days for 5x24h of measurements seems pretty conservative. Is it necessary to cycle
every 24h? Can you cycle the fridges of the receivers you aren't mapping?
2) B2 had scheduled moon maps for the 12th to the
15th, but the sun is actually very close to the moon
until the 16th. Instead, we will try to finish thermal maps before the moon comes up, and
do moon maps
from the 16th to the 19th. This was the time alloted to RPS before, but it will not be
available for B2
anyway by this time.
3)Keck will prioritize RPS maps for the three receivers that are to come down early, and
continue RPS
maps on the other receivers after we have started to warm up. We can catch up on RPS and
Uber chopper
maps for RX0 and RX2 in December to try to get RPS on Bicep2 earlier.
Please remember that Keck's critical path hinges on how quickly we finish B2's
final measurements, warm up, and get D2 out. Delaying any B2 measurements for Keck ones
only hurts Keck.
4)B2 will probably have to sacrifice some of the week
long far sidelobe testing or all of the slippage
time if we are going to try to fit RPS in for them. That would be roughly the 25th-30th
of November.
Well, that _is_ what slippage time is for.
Do we know how long the far sidelobe schedules will take? Abby?
John
On 11/12/12 8:37 PM, Staniszewski, Zachary (Guest) wrote:
Notes from Pole from the last few days. Zak writing
for Chin Lin, Jamie, Colin, Steff, Jon
Please forward this on to B2 list as it will probably bounce coming from this USAP
address.
Friday Nov 9th:
Colin arrived the day before with RPS and Uber chopper. Assembled and put up Uber Chopper
for BICEP2. Installation actually went really smoothly given its size.
Chin Lin worked on RPS assembly and leveling.
Saturday Nov 10:
More RPS assembly. Started B2 thermal maps with Uber chopper.
continued thermal maps on Keck with Ze Choppa
First round of Bicep2 data demodulation, tried to get it out on sptr, but turned out we
were blocked for sending too many small files
Sunday Nov 11:
Put RPS on DSL mast!
DSL mast did not have any high guide wires, so we had to become riggers for the day and
rig up some steel cable to level and stabilize the mast. Very successful, we are now
monitoring level with B2 GCP and will estimate level fluctuations due to wind.
Started 3 hour raster style beam map at night to verify the source.
Steff managed to send out the data files from Saturday.
Monday Nov 12:
Turned out the chop ref or pin switch was not working on the overnight beam map. Took RPS
down, debugged lots of components and it ended up being one of the D-cables inside. Fixed
this.
Found chopped source in timestreams, started another raster style map just to verify the
source works. Verified we see the source.
Chin Lin learned how to put files on sptr for Bicep2. There should be Bicep2 data up
north for Randol to analyze.
Tuesday Nov 13(today):
Chin Lin found a problem with B2 uber chopper maps, no demodulated signal. Narrowed it
down to the reference flaking in and out, possibly because we have been messing around so
much by the B2 mount for the RPS. This intermittent problem is still being debugged, but
probably made most of a day worth of beam maps useless. Randol finds the chop speed of the
uber chopper to be too slow (~10 Hz). We are planning to take slower rasters with Bicep2
to make up for the slow chop speed.
Colin tested a short part of an RPS schedule. Part way through, lost communication with
RPS and schedule hung. Colin debugging now. Source is behaving and he can control the
stage, so possibly a network error.
Jon arrived today, said goodbye to Cynthia. Jon doing a cryo fill with Steff, so Chin Lin
and Zak are off the hook except for being backup and support for fills.
Notes on delays and schedule:
1) We were supposed to have finished RPS data taking yesterday. Instead, we havent
started and we figure we need between 7-10 days of data taking to do the ~24 hour
schedules for 5 dk angles and to fridge cycle between each measurement.
2) B2 had scheduled moon maps for the 12th to the 15th, but the sun is actually very
close to the moon until the 16th. Instead, we will try to finish thermal maps before the
moon comes up, and do moon maps from the 16th to the 19th. This was the time alloted to
RPS before, but it will not be available for B2 anyway by this time.
3)Keck will prioritize RPS maps for the three receivers that are to come down early, and
continue RPS maps on the other receivers after we have started to warm up. We can catch up
on RPS and Uber chopper maps for RX0 and RX2 in December to try to get RPS on Bicep2
earlier.
4)B2 will probably have to sacrifice some of the week long far sidelobe testing or all of
the slippage time if we are going to try to fit RPS in for them. That would be roughly the
25th-30th of November.
_______________________________________________
KeckArray mailing list
KeckArray(a)lists.stanford.edu
https://mailman.stanford.edu/mailman/listinfo/keckarray
--
___________________________________________________________________
John Kovac jmkovac(a)cfa.harvard.edu
Assistant Professor, Astronomy and Physics, Harvard University
160 Concord Ave rm 310, Cambridge MA 02138, 617-496-0611
11:15 p.m.
New subject: [keckarray] Pole notes: Nov 13
The uber chopper can be made to chop faster than 10 Hz
with more
current--please consider whether you want to push that more. Of course
the point of it is higher S/N, and there is probably little 1/f penalty
between 10 and 18 Hz, so somewhat slower rasters as a way to add more
integration time may be just fine.
The slower scans should be fine - I'm not worried about the 1/f penalty, just want to
be sure to get many chop cycles over the main beam.
Do we know how long the far sidelobe schedules will
take? Abby?
The schedule that I wrote covers the entire focal plane at dk=[0,180] and [90,270] in a
little under 12 hours. I count 4 source configurations, so we're looking at ~48
hours of data taking. Of course these things always take longer than you think
they're going to.
John
On 11/12/12 8:37 PM, Staniszewski, Zachary (Guest) wrote:
Notes from Pole from the last few days. Zak
writing for Chin Lin, Jamie, Colin, Steff, Jon
Please forward this on to B2 list as it will probably bounce coming from this USAP
address.
Friday Nov 9th:
Colin arrived the day before with RPS and Uber chopper. Assembled and put up Uber Chopper
for BICEP2. Installation actually went really smoothly given its size.
Chin Lin worked on RPS assembly and leveling.
Saturday Nov 10:
More RPS assembly. Started B2 thermal maps with Uber chopper.
continued thermal maps on Keck with Ze Choppa
First round of Bicep2 data demodulation, tried to get it out on sptr, but turned out we
were blocked for sending too many small files
Sunday Nov 11:
Put RPS on DSL mast!
DSL mast did not have any high guide wires, so we had to become riggers for the day and
rig up some steel cable to level and stabilize the mast. Very successful, we are now
monitoring level with B2 GCP and will estimate level fluctuations due to wind.
Started 3 hour raster style beam map at night to verify the source.
Steff managed to send out the data files from Saturday.
Monday Nov 12:
Turned out the chop ref or pin switch was not working on the overnight beam map. Took RPS
down, debugged lots of components and it ended up being one of the D-cables inside. Fixed
this.
Found chopped source in timestreams, started another raster style map just to verify the
source works. Verified we see the source.
Chin Lin learned how to put files on sptr for Bicep2. There should be Bicep2 data up
north for Randol to analyze.
Tuesday Nov 13(today):
Chin Lin found a problem with B2 uber chopper maps, no demodulated signal. Narrowed it
down to the reference flaking in and out, possibly because we have been messing around so
much by the B2 mount for the RPS. This intermittent problem is still being debugged, but
probably made most of a day worth of beam maps useless. Randol finds the chop speed of the
uber chopper to be too slow (~10 Hz). We are planning to take slower rasters with Bicep2
to make up for the slow chop speed.
Colin tested a short part of an RPS schedule. Part way through, lost communication with
RPS and schedule hung. Colin debugging now. Source is behaving and he can control the
stage, so possibly a network error.
Jon arrived today, said goodbye to Cynthia. Jon doing a cryo fill with Steff, so Chin Lin
and Zak are off the hook except for being backup and support for fills.
Notes on delays and schedule:
1) We were supposed to have finished RPS data taking yesterday. Instead, we havent
started and we figure we need between 7-10 days of data taking to do the ~24 hour
schedules for 5 dk angles and to fridge cycle between each measurement.
2) B2 had scheduled moon maps for the 12th to the 15th, but the sun is actually very
close to the moon until the 16th. Instead, we will try to finish thermal maps before the
moon comes up, and do moon maps from the 16th to the 19th. This was the time alloted to
RPS before, but it will not be available for B2 anyway by this time.
3)Keck will prioritize RPS maps for the three receivers that are to come down early, and
continue RPS maps on the other receivers after we have started to warm up. We can catch up
on RPS and Uber chopper maps for RX0 and RX2 in December to try to get RPS on Bicep2
earlier.
4)B2 will probably have to sacrifice some of the week long far sidelobe testing or all of
the slippage time if we are going to try to fit RPS in for them. That would be roughly the
25th-30th of November.
_______________________________________________
KeckArray mailing list
KeckArray(a)lists.stanford.edu
https://mailman.stanford.edu/mailman/listinfo/keckarray
--
___________________________________________________________________
John Kovac jmkovac(a)cfa.harvard.edu
Assistant Professor, Astronomy and Physics, Harvard University
160 Concord Ave rm 310, Cambridge MA 02138, 617-496-0611
_______________________________________________
Bicep2-list mailing list
Bicep2-list(a)lists.fas.harvard.edu
https://lists.fas.harvard.edu/mailman/listinfo/bicep2-list
13 Nov
13 Nov
8:52 a.m.
New subject: [keckarray] Pole notes: Nov 13
On 11/12/12 11:15 PM, Randol Aikin wrote:
Another thought: as a last thing we might try running a B1-style
sidelobe schedule, to produce directly comparable sidelobe maps. These
are brief (I recall < 12h). They involve 360 DK rotation as we step
away from the source. We've never done it with B2 out of concern for
the DK cable wrap wear and tear. I think in final days on the mount we
can try it, if someone babysits.
J
--
___________________________________________________________________
John Kovac jmkovac(a)cfa.harvard.edu
Assistant Professor, Astronomy and Physics, Harvard University
160 Concord Ave rm 310, Cambridge MA 02138, 617-496-0611
Do we know how
long the far sidelobe schedules will take? Abby?
The schedule that I wrote covers
the entire focal plane at dk=[0,180] and [90,270] in a little under 12 hours. I count 4
source configurations, so we're looking at ~48 hours of data taking. Of course these
things always take longer than you think they're going to.
14 Nov
14 Nov
1:59 p.m.
New subject: [keckarray] Pole notes: Nov 13
Do we know how long the far sidelobe schedules will
take? Abby?
The schedule that I wrote covers the entire focal plane at dk=[0,180]
and [90,270] in a little under 12 hours. I count 4 source configurations, so we're
looking at ~48 hours of data taking. Of course these things always take longer than you
think they're going to.
J
--
___________________________________________________________________
John Kovac jmkovac(a)cfa.harvard.edu
Assistant Professor, Astronomy and Physics, Harvard University
160 Concord Ave rm 310, Cambridge MA 02138, 617-496-0611
_______________________________________________
Bicep2-list mailing list
Bicep2-list(a)lists.fas.harvard.edu
https://lists.fas.harvard.edu/mailman/listinfo/bicep2-list
13 Nov
13 Nov
11:01 a.m.
New subject: [keckarray] Pole notes: Nov 13
Hi Randol,
I count up to 16 configurations:
4 Source Brightnesses (2 are repeats of last year, one dimmer than both of those, and one
in between those).
Forebaffle on/off
2 Polarizations
If each takes 12 hours, this is 8 days of data taking not including cycling the fridge,
which does not fit in the time allotted at this point. I don't think we need to do
all of these configurations, but should decided which to do and which to skip.
Abby
On Nov 12, 2012, at 11:15 PM, Randol Aikin wrote:
The schedule that I wrote covers the entire focal
plane at dk=[0,180] and [90,270] in a little under 12 hours. I count 4 source
configurations, so we're looking at ~48 hours of data taking. Of course these things
always take longer than you think they're going to.
12:50 a.m.
New subject: [keckarray] Pole notes: Nov 13
Hi John,
The uber chopper can be made to chop faster than 10 Hz
with more
current--please consider whether you want to push that more. Of course
the point of it is higher S/N, and there is probably little 1/f penalty
between 10 and 18 Hz, so somewhat slower rasters as a way to add more
integration time may be just fine.
Colin thought that 24V was the max for the motor. We are currently running it at 28V.
There was an assumed voltage drop, but that voltage drop was not measured. We could go up
and measure the voltage drop and possibly tweak it higher, but we do not see gaining more
than 1-2 Hz.
-Zak
7:44 a.m.
New subject: [keckarray] Pole notes: Nov 13
On 11/13/12 12:50 AM, Staniszewski, Zachary (Guest) wrote:
Hi John,
Hi Zak/Colin,
The motor is rated for 600 RPM (20 Hz chop), but the load is high and
sounds like you are close to the max. Current is more useful to watch
than voltage. It's rated up to 3 A. In the cold, a bit higher is
probably OK. Abby's sending an identical spare motor down with Howard.
But the slower scan speed sounds good--at least for B2, which can afford
the time.
John
--
___________________________________________________________________
John Kovac jmkovac(a)cfa.harvard.edu
Assistant Professor, Astronomy and Physics, Harvard University
160 Concord Ave rm 310, Cambridge MA 02138, 617-496-0611
The uber chopper can be made to chop faster than
10 Hz with more
current--please consider whether you want to push that more. Of course
the point of it is higher S/N, and there is probably little 1/f penalty
between 10 and 18 Hz, so somewhat slower rasters as a way to add more
integration time may be just fine.
Colin thought that 24V was the max for the
motor. We are currently running it at 28V. There was an assumed voltage drop, but that
voltage drop was not measured. We could go up and measure the voltage drop and possibly
tweak it higher, but we do not see gaining more than 1-2 Hz.
4203
days inactive
4204
days old
bicep2-list@lists.fas.harvard.edu
7 comments
4 participants
participants (4)
-
Abigail Vieregg -
John Kovac -
Randol Aikin -
Staniszewski, Zachary (Guest)