NHSC HIFI DP workshop Caltech, 7-9 February 2011

The HIFI The HIFI InstrumentInstrumentStatus AOTs and CalibrationsStatus AOTs and Calibrations

Pat Pat MorrisMorris

Status, AOTs, and CalibrationsStatus, AOTs, and Calibrations

Steve Lord, Adwin Boogert, Colin Borys (NHSC)

Carolyn McCoey (Univ. of Waterloo)y y ( )Emmanuel Caux, IRAP (ex-CESR)

Thanks Frank Helmich HIFI PI and the HIFI Thanks – Frank Helmich, HIFI PI, and the HIFI Consortium

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Welcome

NHSC teamNHSC teamScienceAdwin Boogert

Carolyn McCoey, U. WaterlooHerschel DP Training “Champions” Group

Adwin BoogertHerschel DP Training “Champions” Group

Colin Borys NHSC H h l DP M G

Emmanuel Caux, IRAPHIFI Co-PIHIFI rep Herschel DP User Group

NHSC rep Herschel DP Mgt Group

Steve LordPat Morris

ep e sc e Use G oupHIFI Users Group

NHSC rep Herschel DP User Group

ApplicationsApplicationsJoan XieAnnie Hoac

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Outline

• Part I: Expectations & Goals, Preliminaries, Data Access• Part II: Instrument Status and Health• Part III: CalibrationsPart III: Calibrations• Part IV: Cross-Calibrations (HIFI vs APEX, SPIRE)• Part V: AOT Status

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Expectations & Goals

• Learn HIPEBecome familiar with the GUI concepts and usage, how to execute

pipelines and explore your datapipelines and explore your data

• Learn where to find templates data reduction scripts and how to use them... and import and execute custom scripts

• Learn how to read/ingest your data in HIPE• Learn how to process HIFI data to Level 2+ products• Learn how to process HIFI data to Level 2+ products• Learn about resources and support NHSC can provide• Processing ➫ science in HIPE with CASSIS (joint session)g (j )• Sessions will use public data for demo and practice

purposes.

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Preliminaries

• Do you have the right version of HIPE installed?• Where are the data?

– Should I have them already?S ou d a e t e a eady– What if I don’t?– How do I ensure I’m ready to go?

• Where are the scripts?• Where are the scripts?• What are tutorials?

• The next two presentations will answer these questions.

☕ We have allowed for some time to be used for testing your setup(before/during coffee)

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Data access this week

ESA Mission Ops Center

NHSC/HIFI has reprocessed data in

HIPE 5.1, and provided in local stores

HIFI ICCDB

HIPE

in local stores

HSAESAC, Madrid

NHSC/HIFI DB

You @ NHCS

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You @ NHCS

Data access at t > this week

ESA Mission Ops Center

HIPE

HSA

ESAC, Madrid

The HSA is the onl repositor of

You @ home

The HSA is the only repository of observations and calibrations that can be accessed by the observing community.

Help from NHSC and HSC always available

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Help from NHSC and HSC always available.

Part IIInstrument health and status

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HIFI Single Event Upsets

• An SEU in August 2009 attributed to CR on a sensitive memory chip in the LO control unit caused premature power-off of th LOU killi HIFI’ P i id (DC/DCthe LOU, killing HIFI’s Prime side (DC/DC converter failure)• HIFI runs on its REDUNDANT side since February 2010, with new intensive fault yprotection S/W. • SEU occurring statistically every 12 days• Recovery now well established and rapid.• One full power cycle (last resort) has been required, when HIFI stopped reacting to commands.• ~2 ODs lost to LCU SEUs2 ODs lost to LCU SEUs • 5 ODs lost to ICU SEUs but PACS rescheduled so no observatory time lost.

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LSU OXCO Anomaly

• HIFI’s 10 MHz signal (for locking LO chains, LSU, WBS and HRS) is generated by a crystal.

• Crystal is heated to 100º C for best performances– The heater circuit is not working well. Temperatures began spiking in

June 2010, investigation concluded that the circuit is reacting to LSU , g gtemperature control switching to an on/off mode.

• The LSU and HIFI are operating within design specifications, and the The LSU and HIFI are operating within design specifications, and the crystal temperature is within the nominal tolerances so science observations are not affected.

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LSU OXCO scenarios

We cannot change anything in software or by commanding. We have to wait and see what happens, three scenarios are possible :

• Situation remains stable– Currently science data are not affected– Keep operating HIFI as isKeep operating HIFI as is

• Heater circuit dies, but crystal keeps workingDrift of HIFI freq enc e pected that needs to be characteri ed – Drift of HIFI frequency expected that needs to be characterized, especially at the “jump” (may then stabilize)

– Dedicated characterization + observing known lines every OD

• Heater circuit dies, takes crystal with it End of HIFI

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WBS-V comb fade

• WBS-V comb has a failed component, already discovered in 2007– The WBS-V could not be removed and repaired.

• Comb power continued to dropp p– Steep decay between OD 320 and OD 420, lighter since– No remaining attenuation in subband 4 (2-3 dB in others)

• Comb line intensity dropped to < 40 counts much lower than specs• Comb line intensity dropped to < 40 counts, much lower than specs.

S/N still > 400 in sub-band 4

Possible reduction of accuracy in determining comb line positions

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Possible reduction of accuracy in determining comb line positions, reduced frequency calibration accuracy expected

HRS-WBS cross calibration

• Measure pair of spectra with WBS and HRS at any input (preferentially from internal 100 K hot load)

• Compute mutual correlation as function of relative shift

• HRS can be positioned to cover almost the full WBS scale

• Some On-Board S/W bugs to use Some On Board S/W bugs to use this being worked out.

• Accuracy of about 100kHz (best case 30kHz)case 30kHz)

• No issues with WBS-H so far.

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Reality Check

• The HIFI team has been working through so-called Failure Mode Effects and Critical Analysis (FMECA) since assembly and test phases.– A lot of things are related to problems anticipated at launch– Secondary are all the power supplies, which are supposed to be robust,

however, not guaranteed

• Tens of items exist that say “switch to redundant” – that option was required already during PV, thus is no longer available and thus we operate with numerous possible single point failures

• The FMECA is on functional level Hundreds of components can cause a functional problem.p

Chance that HIFI survives the remaining mission is not close to 100% anymore

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anymore

Part IIICalibrations

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LO Spurs and Spurious Response

• Impurity features in HIFI are manifest as ~25MHz, Gaussian-shaped features in hot, cold, on, and off data.

Hot and Cold Loads from an observation in band 1a

• Both WBS and HRS are affected.– Because they look a lot like astronomical lines, they can fool users.

• The repeatable ones are tabulated in PHS (HSpot) and pipeline tables.– In the pipeline, the hot/cold loads are searched in all science observations,

and spurs are flagged.

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Spur clean-up at instrument level

Many of the most troublesome impurities (e.g. near key lines) have been cleaned up, by (time/labor intensive) tests and changes to multiplier settings and bias voltages. H

Band 1a spur eliminated (557 GHz H2O line region)

H

System temperature increased at upper 1.5 GHz of band

VV

Sensitivity in band 1a is better than that in band 1b for LO frequencies up to 551.9 GHz.

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Band 5b purification

• LO-band 5B had several LO spikes at the same time– Result is that the IF consists of several frequency bands superposed on

each other. Calibration of all frequencies within the IF was unknown

– Purification efforts took many weeks.– AORs in 5b were released in December 2010.

• Band 5B was not alone in impurities but in the diplexer bands the diplexer can moved and the signal evaluated at each setting to give purest signal more efficiently (in observing terms).– Purification in bands 3b/7b done this way (Band 5 has no diplexing).

• Purification is a major triumph for modeling of the LO chains!

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Sensitivities

• Sensitivities are driven mainly by System Temperatures and Aperture (or beam) Efficienciesbeam) Efficiencies.

• Tsys remains essentially as measured just before launch --- some small changes at specific frequencies to mitigate impurities and unstable tunings

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unstable tunings.

Beam Calibrations

• H/V beam sizes and co-alignment

• Measured mainly from Saturn, Uranus, MarsMars

• Beam offsets are taken into account in the HIFI pipeline since 5.0

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Efficiencies

• Beam efficiencies measured on Mars

+ Overall ~10% better than pre-launch estimates

o Data taken before Nov 2010 should have somewhat better noise performance (HSpot 5.2 uses updated effciencies).

– Band 5a/b are an exception, ~10% lower.

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Error Budget

Error source B1/B2 B3/B4 B5 B6/B7Error source B1/B2 B3/B4 B5 B6/B7Sideband ratio <10% <30% <10% <30%

Hot Load Coupling <1% < 1% < 1% < 1%

Cold Load Coupling <1% < 1% < 1% < 1%

Hot Load Temperature < 1% < 1% < 1% < 1%

Cold Load Temperature < 1% < 1% < 1% < 1%Cold Load Temperature < 1% < 1% < 1% < 1%

Beam efficiency 5-10% 5-10% 5-10% 5-10%

Pointing (APE+co-alignement) < 5% < 5% < 5% < 5%

Standing Wave 2-4% ? ? ?

Total (quadratic sum) <16 % <32 % <15% <32%

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Part IVPart IVCross Calibrations

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HIFI / Ground

• Comparison made of HIFISTARS spectra with APEX spectra (CHAMP+ SRON/NOVA mixers in MPIfR instrument)

• Scaling consistent with different beam sizesg

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HIFI - SPIRE

From HIFISTARS program Continuum less reliable for HIFI at higher frequencies (drift)

Observations not optimized for Observations not optimized for continuum measurements

HIFI VHIFI-VHIFI-H

Good agreement in continuum at low frequencies

CO 10-9 in CRL618

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Part VPart VAOT Status

(Not an Intro to the AOTs)(Not an Intro to the AOTs)

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HIFI AOTs in OT1(mid-November 2010)

Relative distribution of SScan and Map times is ~reversed from GT/OK KPs.

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Band requests in accepted OT1 programs

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General StatusNot quite

• All HIFI Observing Modes released and being scheduled.Certain restrictions and recommendations remain in place:– FSwitch with Spectral Scans is forbidden in Bands 6 and 7.

Not quite… see next slide!

p• LO power is difficult to stabilize between ON and OFF (throw). • If FastDBS can’t be used, LChop is the alternative.

– FSwitch with OTF maps is forbidden in Bands 6 and 7, except over a range of frequencies around 1897 GHz (C+ tuning).

– Fast(chop)DBS is recommended over DBS in Bands 6 and 7.

– All FSwitch and LChop with all modes should be taken with sky reference, 3 4 6esp in the diplexer Bands 3,4,6,7.

• Data which were taken inconsistent with these recommendations

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(mainly AOT tests and some early PSP/SDP data) to be dealt with in IA.

Some systematic issuesSpectral Scans

WBS-V leveling/saturations

• Certain LO tunings in Spectral Scans g plead to strong IF instabilities, as a result of saturating the WBS-V on the hot load.

• First noticed over ~1061 – 1090 GHz; investigation reveals other isolated ranges over most all bands. 4a and 6a most affected (SScans there on hold) 3a/b least affected (SScans there on hold), 3a/b least affected.

• Several problems lead to this behavior …fe.g. initial power levels deduced from the cold loads.

…will be corrected by increasing the WBS attenuator tuning grid and update to power level tables where not sufficiently covered AOT validation (remember HIFI went on a “fast-track” release after loss of Prime side) Testing in progress

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on a fast track release after loss of Prime side). Testing in progress.

Some Systematic IssuesSpectral Maps

• OTF mapping modes were the last ones to release, could not receive detailed attention during HIFI’s “time-out”.

• Several changes were necessary:– Sky sampling definitions (Nyquist vs

f“half-beam”)• Density: Maps taken < OD 280 uses

Nyquist = HPWB/2. (half-beam), > 280 Nyquist ~ /2D. yq /

• DBS Raster affected also.

– Compensation for a “zig-zag” effect• Slight timing mis-correlations due to

command timing in the uplink system, scan speed granularity. Overall not major problems but could affect what the user

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expected vs sees in the data. OTF only.

More details on Observing Mode performances…

• Are in the HIFI AOT Release Notes at HSC:http://herschel.esac.esa.int/AOTsReleaseStatus.shtml

– Update to the AOT Release Notes for OTF modes is pending (next week!)

• The site also contains informational notes about• The site also contains informational notes about– Beam efficiency calibrations, and effects in HSpot and the pipeline.– H/V beam pointing in the pipeline.

• More info on the data by mode will be covered by Carolyn (Level 1 and 2 pipeline overview), and in the mode-specific presentations and demos.

• Further resources (pages, online and video tutorials, science tools) will be explained during the workshop, and summarized at the end to take

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all inputs into account.

Questions?

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