Optical Endcap Alignment

Transcription

1 Ij Optical Endcap Alignment From the User Perspective Christoph Amelung Brandeis University Ij IATLAS Muon Week December 8, 2009j ji

2 IOutlinej Where do the alignment data come from? How are the alignment data organized? What alignment data are available? How to use alignment data in reconstruction? What do alignment data look like? ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 2 of 14I

3 IWhere Alignment Data Come Fromj Alignment data acquisition: PVSS+LWDAQ data acquisition system running at Point-1 (integrated with DCS, to some extent) takes images, analyzes them, stores analysis results in online DB (replicated to offline DB, occasionally significant delay) one cycle through all images every minutes raw alignment data (sensor measurements) Alignment reconstruction: ARAMyS reconstruction software running outside Point-1 (two separate and independent instances for sides A and C) reads sensor measurements from offline DB, reconstructs chamber alignment one reconstruction run every 60 minutes, always using most recent available (and valid) measurement from each sensor output: A-lines (positions/rotations), B-lines (deformations), diagnostics (χ 2 and pulls) validation (eliminate bad runs) reconstructed alignment data (A-/B-lines) stored in Oracle DB, migrated (=copied) to offline COOL DB ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 3 of 14I

4 IHow Alignment Data are Organizedj Tags and IoVs: an IoV (interval of validity) is the range in time for which the set of alignment data associated to it is supposed to be used a tag is an identifier describing the part of a detector (barrel/ec-a/ec-c) which a set of alignment data is for, plus information about the source of the data (optical, tracks, combined) and the configuration of the reconstruction program usually many IoVs are associated to the same tag, covering a sequence of time ranges; for a given time t, there may exist several IoVs in different tags (no more than one IoV in each) think of tags and IoVs as folders and subfolders in a filesystem; alignment data then are files in the subfolders EC_A_TAG_XXX t t t t t t IoV #1234 IoV #1235 IoV #1236 IoV #4321 IoV #4322 IoV # EC_C_TAG_XXX IoV #1238 IoV #1239 IoV #1240 IoV # EC_C_TAG_YYY IoV #2345 IoV #2346 IoV #2348 IoV # ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 4 of 14I

5 IHow Alignment Data are Organizedj A fundamental complication: once alignment data have been used for reconstruction, they must not be modified anymore (not even bugfixes), so that reconstruction results are reproducible forever tag is locked once a tag has been used, cannot write to it anymore (worst case: prompt reconstruction would lock a tag instantaneously) incompatible with operation mode of alignment reconstruction: continuously keep adding new data to a tag, while old data should already be available for reconstruction The solution(s): UPD1 tags: locked at any given moment for the past, can be unlocked for the future to be used for prompt reconstruction (note: alignment always lagging behind, by construction) UPD3 tags: similar, with some fraction of the past unlock-able as well to be used for bulk processing after 24h normal tags: unlocked until they are used for reconstruction; at that moment, create copy of current tag, lock and use copy used for reprocessing (if improved alignment available) ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 5 of 14I

6 IWhat Alignment Data are Availablej Twiki page of available tags: Oracle and COOL tag names, and description of what is inside (still advisable to talk with an expert to understand the details) ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 6 of 14I

7 IWhat Alignment Data are Availablej Alignment data application server: to list IoVs in a given tag, and read back the A-/B-lines and diagnostics (an ASCII version of this tool also exists) ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 7 of 14I

8 IUsing Alignment Data in Reconstructionj How to use alignment data from a given tag in track reconstruction: good question ask it to a software/reconstruction expert (not an alignment expert) How to make sure that alignment data from a given tag were used track reconstruction: several possibilities start by checking job options and log files, look for (the COOL) tag names the ultimate check (probably the only absolutely safe one): download A-/B-lines for the tag and IoV that should have been used, have your ATHENA job print out the actual values szt that it uses and compare for a few chambers ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 8 of 14I

9 IWhat do Alignment Data Look Likej A collection of plots for the endcaps: covering one month of cosmic data-taking (Oct 14 Nov 11, 2009): toroid magnets switched on/off several times; chamber temperatures mostly stable, short periods with readout off plots created by the Telomon monitoring tool, plotting data read back from Oracle DB showing sector A-11 (chosen for no particular reason) ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 9 of 14I

10 ØÓÖÓ Ç ØÓÖÓ ÇÆ ØÓÖÓ ÇÆ ØÓÖÓ Ç ½º ÐÐ ÔÓ Ø ÓÒ Ò ÖÓØ Ø ÓÒ ÓÖ Ú Ö Ú ÐÙ ÓÖ ÔÐÓØ Ñ Ö Ù ØÖ Ø Ò Ú Ù Ð ÔÐÓØ ÓÛ ÓÒÐÝ Ú Ö Ø ÓÒ µ º º IChamber Positionsj z (in-plane precision coordinate) [mm] ¹½º ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 10 of 14I

11 ØÓÖÓ Ç ØÓÖÓ ÇÆ ØÓÖÓ ÇÆ ØÓÖÓ Ç ¼º½¾ ½¼ ÞÓÓÑ Ó Ü ÔÐÓØ ÔÖ Ú ÓÙ IChamber Positionsj z (in-plane precision coordinate) [mm] ¹¼º½ ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 11 of 14I

12 IChamber Rotationsj ¼º¼¼¼ ¾ Ç ØÓÖÓ ÇÆ ØÓÖÓ ÇÆ ØÓÖÓ Ç ØÓÖÓ θs (rotation around tubes) [rad] ¹¼º¼¼¼ ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 12 of 14I

13 ÐÐ ÓÖÑ Ø ÓÒ Ò ÓÖ ÔÐÓØ Ú Ö Ú ÐÙ ÜÔ Ò ÓÒ Ñ Ö ÆÇÌ Ù ØÖ Ø Ô Ö ÓÛ ÓÐÙØ Ú ÐÙ µ ÔÐÓØ IChamber Deformationsj ¼º½ ¼ Ç ØÓÖÓ ÇÆ ØÓÖÓ ÇÆ ØÓÖÓ Ç ØÓÖÓ chamber twist (maximum excursion) [mm] ¹¼º ¼ ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 13 of 14I

14 ISummaryj Alignment data: are available please use them, check them, give feedback next challenge now is to keep the system stable and running for months; do not expect big improvements in analysis and understanding of the data in the near future Chamber stability: chambers within a wheel (EI, EM, EO) move coherently; wheels move relative to each other incoherently EIL4/EEL1/EEL2 are not mounted in wheels, but on the barrel toroid structure, and behave entirely different except for magnets on/off, stability of the endcaps is closer to µm than to 40µm limited by temperature stability perhaps the most surprising feature seen in these data: after turning magnets on or off, EIL4/EEL1/EEL2 stabilize only after 2 days problematic for 1-day magnet-off running Thanks to A. Formica, D. Pomeroy, S. Aefsky, E. Henry ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 14 of 14I

15 IBackup Slidesj Backup Slides ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 15 of 38I

16 IAlignment Correctionsj there is a well-defined convention for communicating chamber positions and deformations to the tracking packages: the AMDB A-lines and B-lines (historically lines in an ASCII file) P lines : nominal chamber positions (each line accomodates up to 8 identical sectors): 8 parameters A lines : corrections to nominal chamber positions (one line per chamber): 6 parameters amdbdoc/amdbmanual.ps B lines : reconstructed chamber deformations and expansion (one line per chamber): 11 parameters ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 16 of 38I

17 IAlignment Corrections: A-linesj Nominal chamber position given in global system: SZT (AMDB) is YZX (ATLAS) after rotation around beam axis by 0, 22.5,45,... Local chamber system: in the endcaps, szt (AMDB) is xzy (μtdr), origin shifted from central plane to first tube layer + offset szt parallel to SZT for barrel chambers, rotated for endcap chambers (different for A/C) Corrected chamber position given in local chamber system: (small) shifts and rotations w.r.t. local chamber system szt ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 17 of 38I

18 IAlignment Corrections: B-linesj Deformation parameters in local chamber system: bp and bn bow of the tubes out of the plane, varying from the short side to the long side eg global expansion tr trapezoid-like deformation, i.e. a rotation in opposite directions of the two outer cross plates in the plane sp and sn sag of the cross plates out of the plane, varying from the high-voltage side to the readout side tw twist, i.e. a rotation in opposite directions of the two outer cross plates around the tube direction bz bow of the tubes in the chamber plane ep and en local expansions, different for the high-voltage and readout sides pg parallelogram-like deformation, i.e. a rotation in the same direction of all three cross plates in the plane ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 18 of 38I

19 IAlignment Corrections: B-linesj Deformation parameters in local chamber system: eg tr bp bn these two are relevant for r(t) calibration sp sn these four are relevant for tracking tw tw this one only affects cross plates, not tubes bz en/2 ep/2 pg ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 19 of 38I

20 IChamber Deformations: B-linesj Magnitudes of deformation parameters (endcap): bp and bn rms: 60 and 40µm max: 470 and 180µm 40 EO & EML4/5 outside ± 100 µm, 5over200µm eg rms: 60 ppm max: 110 ppm (1 ppm = 1 µm/m) tr zero (not used) sp and sn zero (not used) tw rms: 100 µm max: 450 µm bz rms (EI/EM): 15µm max (EI/EM): 70µm rms (EO): 170 µm max (EO): 560 µm EO have built-in non-zero bz ep and en rms: 15 ppm max: 40 ppm pg rms: 390 µm max: 1.7 mm ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 20 of 38I

21 IChamber Positionsj z ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 21 of 38I

22 IChamber Positionsj zoom z ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 22 of 38I

23 IChamber Positionsj t ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 23 of 38I

24 IChamber Positionsj zoom t ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 24 of 38I

25 IChamber Positionsj s ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 25 of 38I

26 IChamber Positionsj zoom s ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 26 of 38I

27 IChamber Rotationsj θz ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 27 of 38I

28 IChamber Rotationsj zoom θz ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 28 of 38I

29 IChamber Rotationsj θt ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 29 of 38I

30 IChamber Rotationsj zoom θt ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 30 of 38I

31 IChamber Rotationsj θs ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 31 of 38I

32 IChamber Rotationsj zoom θs ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 32 of 38I

33 IChamber Deformationsj bp ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 33 of 38I

34 IChamber Deformationsj bn ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 34 of 38I

35 IChamber Deformationsj tw ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 35 of 38I

36 IChamber Deformationsj pg ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 36 of 38I

37 IChamber Expansionj eg (thermal & Zpitch) ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 37 of 38I

38 IChamber Expansionj ep (= en) ICh. Amelungj IEndcap Alignment From the User Perspectivej jslide 38 of 38I