Research Updates

2009.08.11 - Gain Mapping, 9W/10W
2009.08.11 - Vertical dispersion studies
2009.08.11 - nonlin_bpm interpolation grid
2009.08.12 - Closed-beta bump
2009.08.19 - Gain map of 23W (CBPM II)
2009.09.25 - nonlin_bpm Studies - (dx,dy) distributions resulting from resolution, gain errors
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2009.09.16 - Cbar simulation - method, initial tests
2009.09.18 - Cbar simulation - corrected cbar normalization
2009.09.21 - Cbar simulation - with resolution and gain errors (bad RMS values - see 2009.09.24 instead)
2009.09.24 - Cbar simulation - Corrected RMS results from 2009.09.21
2009.10.09 - 6x6 Cbar Simulation - ideal lattice, with radiation damping and resonant beam shaking
2009.10.19 - 6x6 Cbar Simulation - Diagnosing cbar simulations
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2009.10.29 - Cbar Simulations - Two major typos corrected. Results prior to this are not valid. See newer plots here.
2009.11.03 - Cbar Simulations - Typo in Python analysis script caused the wrong "Cbar vs. Gain Errors" to be plotted on 10/29/09. See corrected plots here.
2009.11.05 - Gain Map Simulations - 2D contour plots of gain map fits vs. grid spacing, # of grid points.
2009.11.05 - Cbar22 Simulations - Response of Cbar22 to applied BPM tilts.
2009.11.09 - Cbar Simulations - Expand on plots from 2009.11.03 to include both gain and tilt errors, as 2D contour plots.
2009.11.09 - Cbar22 Simulations - Expand on plots from 2009.11.05; fit simulated BPM tilts in CESRv.
2009.11.13 - Cbar22 Simulations - How do residual coupling and gain errors affect the quality of BPM tilt fit for Cbar22 data?
2009.11.17 - Cbar Simulations - Is there a significant improvement in quality-of-fit if we use Cbar11 + 22 data in CESRv? Can we fit Cbar12 with vert. steerings first?
2009.11.17 - Gain Map Simulations - Now that bsim_cesr has been restructured as a library, how well can we fit various gain errors at different resolutions? How do these gain errors affect BPM tilt fits using Cbar data?
2009.11.19 - Vertical Dispersion Simulations - Using the results of our 'ideal' gain map and BPM tilt fits, are we able to make a 1cm vertical dispersion measurement?
2009.11.20 - Vertical Dispersion Simulations - Repeat studies from 11/19/09, with averaging 1000 turns / orbit measurement.
2009.11.20 - Fitting Cbar22 with BPM Tilts (actual data) - Using Cbar data taken during today's machine studies, see what fitted BPM tilts look like.
2009.11.22 - Measurement repeatability - Orbit, dispersion; fitting Cbar with BPM tilts
2009.11.23 - Gain map repeatability - Map (21E:24E) 3 times. Look at agreement between maps.
2009.11.24 - Cbar/Tilt Measurement repeatability - Standard 2085mev and cta_2085mev_25nm_20091123.lat data.
2009.12.07 - Turn-By-Turn data simulation - Button responses, amplitudes for full 6x6 tracking
2009.12.07 - Fitted BPM Tilts - Further analysis regarding data from 2009.11.22-23.
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NOTE: Axes are flipped on tune scan plots between 2010.02.16 - 2010.04.28. Starting at 2010.04.28, axes are corrected. Previous tune scan plots are obsolete anyway, and only shown for completeness.
NOTE: Axes are NOT FLIPPED on tune scans-- the original polarity was correct! However, polarity of frequency maps does appear to be flipped... -JSh, 2011.10.20

2010.02.16 - Tune scan analysis
2010.02.22 - Tune scans for 2fam lattice
2010.03.03 - Tune scans - cta_2085mev_xr20m_20091205.lat, 2fam, with quad, bend, and sextupole errors
2010.03.04 - Tune scans - cta_2085mev_xr20m_20091205.lat, 2fam, with QUAD errors only
2010.03.04 - Tune scan - vary amplitudes - cta_2085mev_xr20m_20091205.lat, 2fam, with quad, bend, and sextupole errors. Vary initial amplitude (x,y,\delta) to 10%, 50% of values from 2010.03.03.
2010.03.05 - Tune scans - Typo corrected in tune_scan; re-run jobs from 2010.03.03, 2010.03.04
2010.03.08 - Tune scans - Scale x,y,z amplitudes to ~1.5-3 sigma; L0RF with errors
2010.03.11 - Tune scans - Introduce sextupole errors at the 0.1-5.0% levels.
2010.03.16 - Tune scans - High-res scan of 1% sextupole K2 errors; high-res scans of 3MV, 8MV lattices.
2010.03.19 - Tune scans - CHESS pretzel lattice (with and without sextupole errors); xquneing to different xi's for XR20m lattice.
2010.04.08 - Tune scans - cta_2085mev_20081107 lattice, with new sextupole distribution from Weiming Guo.
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Note: Tune scan, frequency map plots after this line are all corrected. -JSh,2010.06.22
Note: Tune scan plots should NOT have the reversed axes as previously thought. Items with an asterisk (*) have been plotted on the original axes, and are correct. Frequency map plots are unchanged. -JSh,2011.10.20

2010.04.20 - Compare analytic and "brute-force" methods for calculating dbeta/ddelta and deta/ddelta.
2010.04.23 - contributions to xi(2) from individual elements
*2010.04.28 - first Bengtsson optimizations - dynamic aperture, tune scans; IDEAL 2FAM PLOTS
*2010.05.03 - sextupoles - starting w/ DLR distribution, try a second round of optimization
*2010.05.04 - sextupoles - starting w/ 2fam distribution, try different optimization schemes
*2010.05.05 - sextupole errors - for the best sext distribution in yesterday's jobs, add errors to quad k1's and sext k2's
*2010.05.25 - xi.x,y = 6 optimized sextupole distribution
*2010.06.07 - introduce quad tilt errors - 220 micro-radians for both 2fam and optimized distributions
2010.06.09 - TBT data in KEK-style gain map - compare fits with DLR-style gain map distributions
*2010.06.10 - Comparing sextupole distributions - using Bengtsson's formalism as a basis of comparison.
*2010.06.11 - New sextupole optimization - using the results of yesterday's studies.
2010.06.11 - Comparing gain map fits - using the same data sets, try fitting with different numbers of turns (128, 256, 512)
*2010.06.11 - Frequency map analysis - first tests on 2fam, JSh optimized sextupole distributions.
*2010.06.14 - Frequency map analysis - Apply energy errors to 2fam, jsh_opt sextupoles.
*2010.06.15 - Sextupole optimizations - 2-stage optimization tests.
*2010.06.16 - Sextupole optimizations - Increase weights on alpha.xx,xy,yy and xi(2).x,y
*2010.06.16 - Frequency maps - vary the number of turns tracked and number of turns used for FFTs.
*2010.06.17 - Frequency maps - For 2010.05.04 sextupoles, track 4096 turns, with fft_turns = 512.
*2010.06.21 - DA, tune scan, frequency map - for 2010.05.08 sextupoles
2010.06.22 - Measured tune scans from 2010.05.08.
*2010.06.23 - D-line xBSM orbit - dynamic aperture, tune scan, frequency map for "NORM", "BIGD", with both 2fam and JSh-optimized sextupoles.
*2010.06.24 - Effects of physical aperture on frequency maps - "BIGD" lattice with optimized sextupoles, with flat orbit and D-line xBSM orbit.
*2010.06.24 - Quad Errors on BIGD Lattice with D-Line xBSM Orbit - 220 micro-radian tilts, 125 micron vertical offsets.
*2010.06.24 - Frequency maps with energy offsets - BIGD lattice with optimized sextupoles, D-line xBSM orbit
*2010.06.29 - Frequency map with 2048 turns / 1024 per FFT - for 2fam
*2010.07.01 - Change working point - for 2fam and JSh-optimized sextupoles, "NORM" lattice.
*2010.07.06 - Full-Span Frequency Maps - for 2010.05.04 optimized sextupoles, expand frequency maps to x = 40mm.
*2010.07.13 - Ecloud tune shift - frequency map jobs with +10kHz tuneshifts
2010.07.13 - sextupole optimizations at proposed working point (0.578,0.542)
2010.07.14 - frequency map analysis summary - through 2010.07.12; PDF (uncorrected x/y flip as of 2011.10.20)
2010.07.14 - Updated frequency map, tune scan plots for 2fam, JSh-optimized sextupoles - NORM lattice (can't find sources; uncorrected as of 2011.10.20)
2010.07.15 - More proposed working points - NORM lattice, 2fam / 2010.05.04 sextupole distributions
2010.07.15 - Frequency map analysis, scanning over delta - NORM lattice, 2fam / 2010.05.04 sextupoles.
2010.07.16 - sextupole optimizations at proposed working point (0.625,0.542)
2010.08.25 - Introduce quad misalignments, k1 errors; tune scans, frequency maps
2010.08.26 - In a wiggler-free lattice, re-run sextupole optimizations.
2010.08.27 - Nonlinearities in button response (simulation)
2010.08.31 - amplitude-dependent tuneshift in a wiggler-free lattice (simulation)
2010.11.11 - Sextupoles - target alpha_yy
2010.11.11 - Sextupoles - high-chromaticity - xqune 2fam to xi=6, then optimize
2010.11.11 - Sextupoles - high-chromaticity - incrementally increase xi target
2011.01.12 - amplitude-dependent tuneshift in a wiggler-free lattice - sextupoles off, ayy; axx (simulation)
2011.11.03 - tune scans for DTC02-1 ILC-DR lattice



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