Bicep2-list November 2012

bicep2-list@lists.fas.harvard.edu

12 participants
16 discussions

by Jonathan Kaufman

Hi All, It's been a busy week of beam mapping. I ran 3 full uber-chopper schedules and 3 full moon raster schedules. All of the data that is ready has been processed and plotted in the analysis logbook. The fridge cycles and cryo fills are out of synch but have been timed so that they occur either at the end of a schedule or after a natural break point. Steff left on monday (pole date) and Jamie left today. Grant and Howard arrived today as well. The weather has been mostly excellent with a few periods of overcast skies, occurring mostly during the time the moon was up. The RPS had broken a couple of times but now it seems to be working fine so as soon as Keck finishes their schedule we can start taking RPS data. The earliest this could be would be friday/saturday. Computers: - restarted gcp - bicep30 hung and then crashed likely due to I/O issues. As a precaution, Steff created a partition on bicep44 separate from the home directory for heavy I/O work. Cryo: - The HDI sensor on Theo had been inaccurate and it ran dry one fill earlier than expected. We still have more than enough Helium to get us through our calibrations. Schedules: • 121119 19:21:14 - • 7_ffflat_moonraster_26_007.sch • 121119 06:50:14 - 121119 19:21:14 • 7_ffflat_moonraster_26_006.sch • 121119 00:34:53 - 121119 06:50:14 • 7_ffflat_moonraster_26_005b.sch • 121118 23:10:00 • LHe fill • Tilts: az 0° 180° x -9.366 -9.146 y 9.371 10.778 • 121118 23:08:15 - 121118 23:08:43 • config_hw.sch • 121118 23:07:04 - 121118 23:07:04 • mediator.init • 121118 04:52:43 - 121118 23:05:38 • 7_ffflat_mapo_28_001b.sch • 121117 22:39:44 - 121117 22:45:19 • do_cycle.sch • 121117 22:39:03 - 121117 22:39:32 • config_hw.sch • 121117 02:20:46 - 121117 22:38:52 • 7_ffflat_mapo_28_001.sch • 121117 02:15:54 - 121117 02:16:23 • config_hw.sch • 121116 19:57:43 - • 7_ffflat_moonraster_26_005.sch • 121116 01:44:16 - 121116 19:57:43 • 7_ffflat_mapo_27_001b.sch • 121116 00:31:00 • LHe fill • Tilts: az 0° 180° x -9.366 -9.146 y 9.371 10.778 • 121116 00:31:39 - 121116 00:32:08 • config_hw.sch • 121115 05:45:35 - • 7_ffflat_mapo_27_001.sch • 121115 00:09:08 - 121115 00:11:12 • 7_ffflat_mapo_27_001.sch • 121114 20:21:30 - 121114 20:27:05 • do_cycle.sch • 121114 20:17:38 - 121114 20:18:06 • config_hw.sch • 121113 04:34:51 - • 7_ffflat_mapo_26_001.sch • Uber chopper running at ∼10 Hz. Chop reference in fast_aux_input[3]. • Al biases same as 7_ffflat_mapo_24_xxx.sch • Slow raster scan, 0.3 deg/sec in az. • 121113 00:13:22 - 121113 00:13:51 • config_hw.sch • Tilts: az 0° 180° x -9.256 -9.168 y 9.338 11.008 • dk=0 • Membrane 0.15/0.45

11 years, 4 months

BICEP2 team meeting + Pipeline call today (16 Oct 2012), 9am Pacific

by John Kovac

Hi all, BICEP2 team meeting today (Tues) at 9-10am Pacific. Thanks to each of you who sent reports AHEAD OF TIME this week, even late last night. Sorry these came too late for me to do the agenda yesterday, but please do look over the below before the meeting. Phone: 1-866-890-3820 (toll: 1-334-323-7229) Passcode:59702175 Walt will take notes <https://docs.google.com/a/cfa.harvard.edu/document/d/1iVrfX19cXQr8fUgRYOUos…> for the team meeting. The bispud pipeline telecon will follow immediately, run by Clem. Except as called out below, all NEW analysis postings will be reviewed in the pipeline telecon, not the main telecon. 1) Weekly report from Pole [ Steff ] - yet another great observing week; good weather - Jon's thermal tests: 3 additional schedules run, report below. 2) Data quality / reduc czar report [ Walt ] AIFL: star pointing cut--fixed AIFL: El nod mismatch 20120929F10 <http://bicep.rc.fas.harvard.edu/bicep2/reducplots/201209/browser/20120929F1…> follow up next week's czar: ________________ 3) Testing and Deployment Planning: Thermal testing report [ Jon ] 5-10 min Oct 9: xfer function low freq <http://bmode.caltech.edu/%7Espuder/analysis_logbook/analysis/20121009_therm…> Oct 14: xfer function high freq (Jon, fix name!) <http://bmode.caltech.edu/%7Espuder/analysis_logbook/analysis/20121014_therm…> data great 0.0001-0.01 Hz, but 1e-3 response at 1 Hz? analysis/modeling needs work (offline!) - are we done taking xfer fun data? - PID characterization status November/DecemberMeasurement Plan <https://docs.google.com/a/cfa.harvard.edu/spreadsheet/ccc?key=0Ao4UxezLygx5…>(view only!) [ Colin (/Randol) ] 5 min - plan for pol rot? (need analysis of last year?) - plan for sidelobe maps? (who writes these schedules?) - plan for analysis? FTS status [ Zak ] 4) Analysis Status Reports: Baseline 2yr data reduction status report [ Walt ] 10-20 min Walt to give overview of this thread [ see his summary report appended below ] Characterizing non-beam systematics [ Walt / Angiola ] brief! briefly list threads / status / people: - relgain mismatch from per-channel abscal still in progress [ Walt ] - crosstalk, new posting to discuss next hour [ JET ] - other threads here: thermal, magnetic, ? Characterizing beam systematics [ Abby (/Randol) ] brief! briefly list threads / status / people: - main beam parameters [ follow up to Randol's post <http://bmode.caltech.edu/%7Espuder/analysis_logbook/analysis/20121004_beams…> last week ] - un-deprojected residuals (main beam and sidelobes) - other threads here: pol calibration errors, ? Deprojection / beamsim algorithm coding status report [ Clem ] brief! briefly list threads / status / people: - deproj sim test of linearity: add timestream noise [ Chris ] - deproj sim test of beam width/ellipticity [ Stefan ] - other: simulation of more complicated beam shapes, ? Data consistency check status report [ Chris (/Randol) ] big news: B2 2yr maps DK_jack cleans up dramatically <http://bicep0.caltech.edu/%7Espuder/analysis_logbook/analysis/20121008_sim1…> with deproj further discussion of new postings in next hour briefly list threads / status / people: - comparison of recovered deproj coefs w/ measured mismatches - full jack chi2's, sum_bp_devs, etc. Foregrounds status report: [ Jamie T ] brief! Statistics for reporting bandpowers, r constraints [ Colin / John ] brief! End. ---- Appendix, from Walt: Baseline two-year data reduction --------------------------------- What we've been doing: * Spent substantial time in 2012 addressing discrete artifacts in the data, including glitches and step-like crosstalk. * Cut definition is nearly complete. * The recent reducplots show the success of these efforts: there are only a very few examples of non-standard behavior remaining in the scan plots. Efforts now in progress and to be completed soon: * El-nod goodness of fit cut: - Now have strong evidence this cut is important for BICEP2: + 2012 Oct 12: Threshold-crossing gain change in GCP 165 (RWO) + 2012 Oct 12: Threshold-crossing gain excursion in more channels (RWO) - Martin has defined several new cut parameters - Angiola will regenerate cutparams files, cutplots, study thresholds - Regenerate cutparams, default cuts when ready. * Other cuts: - Thresholds for stationarity_ab and elnod_mean are now set. - Will take Jamie Tolan's adjustments to scanset_std and tfpu_std. - Angiola to make sure default cut thresholds get updated, include in new cut plots. * Follow-up on the few remaining oddities in reducplots. - Walt working on this now. - May require additional cuts or tweaks to existing cuts, thresholds, or deglitching. - In case of deglitching changes, could require new run of low-level reduction. * NTD calibration - Walt to propose scheme for applying offline cal for periods when needed. - Will redo low-level reduction for this period only. * Once this is done, can define stable TODs / data selection / cuts / pairmaps / reducplots. Next steps: * Write up final observing efficiency, etc. Easy -- follows SPIE papers with a few updates. * Human eyeball test for final version of all reducplots. - Will need volunteers... Decisions to make: * The high-weight catch has been removed from reduc_makepairmaps. Restore in reduc_coaddpairmaps or in reducplots? * How to make maps of dark TESs, dark SQUIDs, NTD? - How to apply cuts? - "clean" version would require substantial changes to code - put off until after BICEP2 first results? -- ___________________________________________________________________ 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 years, 5 months

South Pole notes, 2012-11-27

by Colin Bischoff

hi all, We got a lot done over the weekend, since the last update. [Saturday] * Took down the far field flat. * Moved the RPS from DSL to MAPO and got it working on the bench. [Sunday] * Removed back end electronics from rx3, rx4. * Installed RPS on the MAPO mast, adjusted attenuators, and leveled the source so that BICEP2 can start its RPS schedule. [Monday] * Took down rx3 and rx4 in the morning. * Started opening up rx3/K4 and rx4/K5: - rx4/K5 insert has been removed and the telescope and camera are separated. - rx3/K4 is almost ready to remove the insert * We found a couple of suspects for the rx3 cryogenic problems -- There was a light leak from an open hole that was not taped over near the interface between the 50K tube and the filter stack. The much larger problem is that the tunnel around the 4K strap had a massive hole and seemed to be made primarily from Al tape, not mylar. We took some photos, which I will try to send along later. * Having some new computer issues with the BICEP2 RPS observation. I've been in touch with Walt about this. However, I'm cautiously optimistic that we might have solved the problem by switching to a different USB port on the RPS laptop. [Plan for today] * Sarah arrives! * Get the FPUs out of rx3 and rx4. This will give us a full day for Grant and Howard to remove a tile, as specified in Grant's recent email and responses. * Still trying to track down the FTS, which we think arrived at Pole on Friday. Zak or Jon have the best information about this, so maybe they can provide an update. * Deal with sudden increase in lab clutter caused by opening up two cryostats at once. * Make sure that the B2 RPS measurement is proceeding well. Switch to far sidelobe mapping once that is done (probably not today). -colin

11 years, 5 months

Re: [Bicep2-list] South Pole notes, 2012-11-27

by Clem Pryke

Hi Colin, Sounds like you guys are doing lots of good work down there. > [Monday] > * Took down rx3 and rx4 in the morning. How much violence was required to get them out? We had a super hard time getting the last one in and I am somewhat concerned about thing getting broken - things like screws getting stripped and hoses kinked. Clem -- ********************************************************************** Clem Pryke - Associate Professor - Physics University of Minnesota, Room 313 Tate, 116 Church Street S.E. Minneapolis, MN, 55455 Tel: 612-624-7578 Fax: 612-624-4578 email: pryke(a)physics.umn.edu **********************************************************************

11 years, 5 months

[keckarray] South Pole notes, 2012-11-24

by Staniszewski, Zachary (Guest)

Thanksgiving notes, Saturday November 24th. Today -Finished the last of 5 RPS schedules today! So we got all dk angles observed with the RPS on Keck. -RX3 and RX4 continue to warm up on the mount, on track to be warm on Monday. -Took the far field flat off this morning! Yahoo. -RX0,RX1,RX2 are cooling back down and are all ~4K -RPS taken down off DSL mast and in Mapo lab now. -FTS arrived and is in DNF -The uber chopper stopped spinning two days ago. When we took it apart it was clear that the gears inside the motor are messed up. The problem feels mechanical not electrical when you spin the shaft by hand. We have a spare, but Tomorrow(Sunday) -Take it easy a bit -Continue to warm up, remove back side electronics -Put RPS up for BICEP2 to observe. Monday -Take the two cryostats off the mount -Begin to take cryostats apart -----Original Message----- From: keckarray-bounces(a)lists.stanford.edu on behalf of Colin Bischoff Sent: Fri 11/23/2012 12:28 PM To: Keck Array; BICEP2 group Subject: [keckarray] South Pole notes, 2012-11-23 hi all, We have been progressing well on that schedule that Zak sent around a couple of days ago. We have been keeping the observation logbook up to date (and it should be rsyncing to North America) so check it for details: http://spud.spa.umn.edu/~keckdata/keckdaq_obs_logbook.html * Last night, we shut off the compressors for rx3 and rx4. This was done in series, so that we could check them both for He3 using the RGA. Both tests came out negative, which is good. Rx3 seemed to have a significantly worse vacuum, but that might have been due to small leaks in our vacuum hose system. * We are currently running the last of the five Keck RPS schedules, expecting to finish Saturday morning. This schedule has rx1 centered at the back of the mirror, with some mirror coverage for rx0 and rx2. * Saturday - Take off the Keck ffflat, with help from Jon Kaufman and Steele. Take down the RPS from the DSL mast and move it to the MAPO mast for B2 calibrations. * Sunday - Recover from Thanksgiving. Remove back-end electronics from rx3, rx4. If necessary, finish setting up the RPS for B2. * Monday - Take rx3, rx4 out of the mount and start disassembly. * Tuesday - Finish rx3, rx4 disassembly. * Wednesday - Grant and Howard remove the one good tile that we plan to keep at pole for potential installation into the rx1 focal plane. * Thursday - Zak leaves, hand carrying two FPUs. -colin _______________________________________________ KeckArray mailing list KeckArray(a)lists.stanford.edu https://mailman.stanford.edu/mailman/listinfo/keckarray

11 years, 5 months

Re: [Bicep2-list] [keckarray] Keck Pole update and warmup plan 11/20 -- NO telecon Thanksgiving day

by John Kovac

Hi Zak, Colin, Jon, Chin Lin, Howard, and Grant: Thanks for sending updates yesterday and for calling in to the B2 telecon (until we lost you). Clem is out and due to the holiday we'll skip this week's Keck telecon. I'm in the office today and Friday so you can call me at 617-496-0611 if you'd like to check on on anything. Obviously from your report you guys are working hard, and your plan below (and as discussed yesterday) sounds good. Here are a few comments that may have come after you dropped off the call: 2) B2 will not be very productive between the 20th and 23rd because they are ready for either our mast or the RPS. This should be fine as we can catch up a lot on B2 in short order. On the call yesterday we requested two more sets of B2 uber-chopper maps that you can do during this time: a) DK = +/-45 deg rotation (may need to increase EL range). This is a check of which vertical/horizontal near sidelobe features seen in the DK=0,90,180,270 maps rotate with the instrument. b) stop the uber chopper down to an aperture size similar to ze choppa (or go back to ze choppa). This is because Randol reports some pixels still exhibit non-linear response to the brighter uber-chopper at all the biases tried, and for those pix we can main beam parameters directly comparable with last season's. We discussed whether to do (a) with the full strength or stopped-down uber-chopper, but the meeting notes do not record what we agreed. I think Randol preferred stopped-down (correct if wrong). 3) B2 will have the RPS from the 23rd for 3 days or more, and then can take the pin switch out and use it in the noise source for far sidelobes. 4) Because of point 3), Keck cannot do any mapping for the 23rd-30th unless we put the far field flat on to do uber-chopper. not really a big priority. Instead, Keck will probably start far sidelobe mapping when B2 is done on the 30th. It sounds like Keck will be idle Nov 27-30, due to lack of a second BNS source for simultaneous far sidelobe mapping (unless some of the lower-power B2 far sidelobe maps are done with the uber chopper, which we may want to consider). But I imagine a few days of Keck beam measurement down-time would be fine, given how busy you guys must be. If you have follow-up ideas for PT-excess noise this period may be a chance to pick that up again, at your leisure. Jon K: on B2 thermal characterization, Darren and I were wondering how close we are to closing out those measurements. Have you analyzed the PID bandwidth schedules you've taken and been able to draw/post conclusions? He also mentioned there were a couple outstanding follow-up suggestions for thermal filter measurements. I think the thermal measurement thread is nearly done, but it will be good to hear your wrap-up of it next week. good luck to you all, John On 11/20/12 3:14 AM, Staniszewski, Zachary (Guest) wrote: > Hi All, > We plan on finishing RPS maps up and warming up the two receivers very soon, so I wanted to give both an update and our plan before we pull the plug in a couple days. > Short story on the RPS is that we had grounding problems where the mast would charge and shock and kill the pin switch. We hunted this problem down and fixed it after the second incident. Replaced the pin switch with one on loan from SPT. Spares are on their way. > Our main goal is to run the RPS schedule at 5 dk angles before warming up, and also a couple dk angles of moon observations. We have completed the moon man observations, and 2 of the 5 RPS schedules. We are on track for finishing these measurements on the 23rd which is just enough time to warm up RX3 and RX4, get tiles out, and FPUs into Zak's hands to take out the 29th. > The implications of this are follows; > 1) We will have the RPS data in hand for all receivers. Also the necessary moon data. > 2) B2 will not be very productive between the 20th and 23rd because they are ready for either our mast or the RPS. This should be fine as we can catch up a lot on B2 in short order. > 3) B2 will have the RPS from the 23rd for 3 days or more, and then can take the pin switch out and use it in the noise source for far sidelobes. > 4) Because of point 3), Keck cannot do any mapping for the 23rd-30th unless we put the far field flat on to do uber-chopper. not really a big priority. Instead, Keck will probably start far sidelobe mapping when B2 is done on the 30th. > > Random notes before listing our proposed schedule for the next week. > a) Jamie T. left, Grant and Howard arrived > b) Grant and Howard will check out the wire bonder tomorrow > c) Chin Lin will verify that the moon man maps look good. Already verified that one dk angle looks good. > d) FTS has been pulled forward from CHC and could arrive by the end of the week > e) Zak has Steele working on mast extension for Keck's far sidelobe mapping > f) Colin made a post is working hard on RPS analysis > > Proposed schedule to finish measurements, warm up, and get FPU out on time. Other things will be happening, but this is the stuff relevant to getting the FPUs out. > > 20th, Tues: RX2 RPS > 21st, Wed : RX0 RPS > 22nd, Thu : RX1 RPS, start warming up RX3 and RX4 as they are not on mirror, do some RGA > 23rd, Fri : FFFlat off today because Saturday and Sunday will be hard to find help as it is Xgiving > 24th, Sat : Continue warming up RX3/RX4 and pull off back side electronics > 25th, Sun : Warm up > 26th, Mon : Take RXs out of the mount and start taking the cryostats apart > 27th, Tue : Take RXs apart, getting the FPUs out > 28th, Wed : Grant, Howard do tile removing > 29th, Thu : Zak leaves with the two FPUs > _______________________________________________ > 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 years, 5 months

Plan for taking/analyzing this summer's Pole FTS measurements, both B2 and Keck

by John Kovac

Hi Jon, Grant, Kirit, and Immanuel, I've talked with each of you about the FTS measurements at Pole, which will start with B2 in early December. I just want to facilitate communication on this thread: Jon and Grant have volunteered to take the lead on B2 and Keck measurements, respectively. Immanuel will arrive at Pole ~Nov 5, and Kirit a week later--both will make completing FTS measurements and analysis their top priorities. Since this FTS will return to Harvard they should become expert in using it, and with Grant can hand it off to Abby and me in Jan for final Keck use and retro. We need to turn these data around as quickly as possible, verifying completeness of coverage on our ~250 light B2 detector pairs and data quality as judged by repeatability of conclusions. Our goal should be to take multiple sets of spectra on all B2 rgl's, with different FTS mounting orientations and/or grid polarizations, and verify repeatability of not just the spectra but the actual parameters we derive from them which we will use in analysis. These parameters should include *band centers* for an assumed source spectrum (e.g. CMB), and more importantly predicted *elnod relgain mismatch* as Evan calculated from B1 spectra in this posting. <http://bicep.caltech.edu/%7Ebicep/analysis_logbook_north/20101021_specleak3/> You could start working right now on the analysis that will be needed to derive these parameters from your spectra. A posting could demonstrate repeatability using scatter plots between two measurement sets, and plot significance assessed from scatter among measurements as in this recent posting <http://bmode.caltech.edu/%7Espuder/analysis_logbook/analysis/20121109_BeamP…> on beam parameters. Our goal is to see such postings before warming up B2. We'd like to aim for Dec 10. As you know, Dec 25 is the drop-dead deadline. Please work together, but don't be afraid to produce independent analyses of the same data--we need multiple team members on this to ensure timely convergence. John -- ___________________________________________________________________ John Kovacjmkovac(a)cfa.harvard.edu Assistant Professor, Astronomy and Physics, Harvard University 160 Concord Ave rm 310, Cambridge MA 02138, 617-496-0611

11 years, 5 months

Fwd: [keckarray] Keck Pole update and warmup plan 11/20

by Colin Bischoff

-------- Original Message -------- Subject: [keckarray] Keck Pole update and warmup plan 11/20 Date: Tue, 20 Nov 2012 21:14:07 +1300 From: Staniszewski, Zachary (Guest) <Zachary.Staniszewski.Guest(a)usap.gov> To: <keckarray(a)mailman.stanford.edu> Hi All, We plan on finishing RPS maps up and warming up the two receivers very soon, so I wanted to give both an update and our plan before we pull the plug in a couple days. Short story on the RPS is that we had grounding problems where the mast would charge and shock and kill the pin switch. We hunted this problem down and fixed it after the second incident. Replaced the pin switch with one on loan from SPT. Spares are on their way. Our main goal is to run the RPS schedule at 5 dk angles before warming up, and also a couple dk angles of moon observations. We have completed the moon man observations, and 2 of the 5 RPS schedules. We are on track for finishing these measurements on the 23rd which is just enough time to warm up RX3 and RX4, get tiles out, and FPUs into Zak's hands to take out the 29th. The implications of this are follows; 1) We will have the RPS data in hand for all receivers. Also the necessary moon data. 2) B2 will not be very productive between the 20th and 23rd because they are ready for either our mast or the RPS. This should be fine as we can catch up a lot on B2 in short order. 3) B2 will have the RPS from the 23rd for 3 days or more, and then can take the pin switch out and use it in the noise source for far sidelobes. 4) Because of point 3), Keck cannot do any mapping for the 23rd-30th unless we put the far field flat on to do uber-chopper. not really a big priority. Instead, Keck will probably start far sidelobe mapping when B2 is done on the 30th. Random notes before listing our proposed schedule for the next week. a) Jamie T. left, Grant and Howard arrived b) Grant and Howard will check out the wire bonder tomorrow c) Chin Lin will verify that the moon man maps look good. Already verified that one dk angle looks good. d) FTS has been pulled forward from CHC and could arrive by the end of the week e) Zak has Steele working on mast extension for Keck's far sidelobe mapping f) Colin made a post is working hard on RPS analysis Proposed schedule to finish measurements, warm up, and get FPU out on time. Other things will be happening, but this is the stuff relevant to getting the FPUs out. 20th, Tues: RX2 RPS 21st, Wed : RX0 RPS 22nd, Thu : RX1 RPS, start warming up RX3 and RX4 as they are not on mirror, do some RGA 23rd, Fri : FFFlat off today because Saturday and Sunday will be hard to find help as it is Xgiving 24th, Sat : Continue warming up RX3/RX4 and pull off back side electronics 25th, Sun : Warm up 26th, Mon : Take RXs out of the mount and start taking the cryostats apart 27th, Tue : Take RXs apart, getting the FPUs out 28th, Wed : Grant, Howard do tile removing 29th, Thu : Zak leaves with the two FPUs _______________________________________________ KeckArray mailing list KeckArray(a)lists.stanford.edu https://mailman.stanford.edu/mailman/listinfo/keckarray

11 years, 5 months

Pole notes: Nov 13

by Staniszewski, Zachary (Guest)

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.

11 years, 5 months

BICEP2 polarization angle calibration

by John Kovac

Randol, Colin, Walt, Abby: As we discussed again on the telecon today, we *urgently need* final numbers and uncertainties on BICEP2 polarization angle calibrations before - we calculate spectra from our current (maps and see we've "detected" cosmological birefringence, and - we take B2 off the mount and loose the opportunity to ever measure this again. Our target precision for measuring chi's is 0.1 deg. Each of you have worked on this in the past 3 years. But we still don't firm conclusions on what angles to use, or whether uncertainties are anywhere near that precision. We need an immediate plan, so this is what we came up with on the telecon: 1. Walt and Abby will work together to correct the angles derived from the *Jan 2012 RPS data* for the FFFlat pointing model and register them accurately to focal plane coordinates (assuming a reference theta, as usual) for each detector, as Walt began to do in his 20120322 posting <http://bmode.caltech.edu/%7Espuder/analysis_logbook/analysis/20120322_polro…>. It sounds like they are using Randol's FFFlat pointing model in this. 2. Randol will verify that the chi's derived from *pixel polrasters* by Abby using his code in her 20121112 posting <http://bmode.caltech.edu/%7Espuder/analysis_logbook/analysis/20121112_pxPol…> should in principle be properly registered to focal plane coordinates, given reference theta. If not, Randol and Abby work together to please fix this. Goal: check chi's from 1 and 2 agree. (Randol's code is common to both.) 3. Colin will independently use his own FFFlat pointing model to extract properly registered chi's from RPS data, both Jan and Nov 2012. He reported today that he's checked his FFFlat pointing code and Randol's agree on centroids, but unsure whether they agree on angles--this is an important cross-check. Goal: check angles from Jan and Nov 2012 RPS agree. (Basic data quality check, rule out drifts.) Goal: check chi's from 3 and 1 agree. (Check on complicated FFFlat model) Randol, in addition the Yukical data taken in 2010 was analyzed by you in this posting <http://bmode.caltech.edu/%7Espuder/analysis_logbook/analysis/20110302_yukic…>. You noted in that posting that the Al data looked good, agreed with the model, and could be retaken at any time. Demonstrating agreement between angles derived from that data and from RPS or pixel polraster would be a powerful check (although if we saw systematic disagreement we can imagine explanations). Have you made such a comparison? Is it worth re-taking Yukical data in any case, to compare 2012 vs 2010 Yukical angles? 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

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Bicep2-list November 2012