Performance Metrics: User Time for FY15

Experiment: E200 - Multi-GeV Plasma Wakefield Acceleration Experiments

Shift Start: 2015-06-08 08:00:00

​ Brief Summary:

Explored wide range of parameter phase space. Did not observe acceleration at the expected gas pressure
 (up to 4 torr). Successfully showed acceleration of at least 2 GeV of beam electrons at high pressure
 (~10 torr) in laser-ionized H2 plasma.

Experiment: E225 - Hollow Channel Plasma Wakefield Acceleration

Shift Start: 2015-06-07 16:00:00

​ Brief Summary:

We made a hollow channel, sent a beam through it, and measured the accelerating and decelerating fields.

Experiment: E200 - Multi-GeV Plasma Wakefield Acceleration Experiments

Shift Start: 2015-06-07 04:00:00

​ Brief Summary:

We continued the study if beam wiggles and plasma filament wiggles, by performing transverse scans and pressure scans.

Experiment: E217 - Ionization and down-ramp injection proposal by the E200 team

Shift Start: 2015-06-06 16:30:00

​ Brief Summary:

Parameters affecting the ionization trapping and acceleration of electrons were studied. Data shows that substantial amounts
 of hydrogen dark current is loaded into the wakefield 
which may reduce the energy of ionization-injected electrons. Electrons with ~5 GeV were observed during the shift. 
A wider plasma channel will enable reduced dark current and thus allow the production of ionization
-injected electrons with much higher energy.

Experiment: E225 - Hollow Channel Plasma Wakefield Acceleration

Shift Start: 2015-06-05 23:00:00

​ Brief Summary:

We made and diagnosed a hollow channel plasma.

Experiment: E224 - Visualization of electron-driven plasma wakefield accelerators

Shift Start: 2015-06-05 05:15:00

​ Brief Summary:

Enhanced ionization of the plasma column was observed over a very large range of transverse shifts of the kinoform 
position relative to the electron beam position, as well as enhancement near the ionized column sheath.

Experiment: E210 - Trojan Horse Plasma Wakefield Acceleration

Shift Start: 2015-06-03 14:00:00

​ Brief Summary:

Attempted the Trojan horse injection plasma wakefield acceleration. However, the current diagnostic
 cannot provide information if there is a plasma filament. There is also no significant effect or
 distortion on the ebeam due to the TH laser ionized plasma.

Experiment: E217 - Ionization and down-ramp injection proposal by the E200 team

Shift Start: 2015-06-02 16:00:00

​ Brief Summary:

Injected helium into PWFA in order to create low emittance narrow energy spread beam.

Searched for ionized injected electrons, varied QS and plasma density. 
No obvious trapped electron features were observed.

Experiment: E213 - Temporal Limits of Electron-Phonon Interactions

Shift Start: 2015-06-02 14:00:00

​ Brief Summary:

We successfully exposed new type of samples to short electron bunches. We will evaluate the mechanical effects of strong electromagnetic field on 
nano-patterned thin film structures. We varied the substrate (single crystal, polycrystalline or amorphous) 
and the material for films. This will enable us to test how fast can they deformation occur and what mechanisms are at play.

Experiment: E225 - Hollow Channel Plasma Wakefield Acceleration

Shift Start: 2015-06-01 16:00:00

​ Brief Summary:

Big step forward for the hollow channel experiment. Demonstrated 
that we have the tools to generate and diagnose hollow channel plasmas.

Experiment: E200 - Multi-GeV Plasma Wakefield Acceleration Experiments

Shift Start: 2015-05-30 17:00:00

​ Brief Summary:

We did complementary characterization of the hydrogen source. In particular we characterized an
 beam-plasma instability where the electron beam, originally far away a plasma channel, is sucked into the channel.

Experiment: E210 - Trojan Horse Plasma Wakefield Acceleration

Shift Start: 2015-05-29 18:00:00

​ Brief Summary:

E210 successfully did dark current reduction scans in full charge, fully compressed plasma waves in a 90/10 H2/He mixture. Axicon-preionized 
and self-ionized interaction has been systematically scanned and compared. No plasma filament 
generated by the focused E210 laser has been observed -- deleterious optical elements in beam path have to be removed.

Experiment: E224 - Visualization of electron-driven plasma wakefield accelerators

Shift Start: 2015-05-29 16:00:00

​ Brief Summary:

E224 is becoming the precision diagnostic we hoped it would be.

Experiment: E210 - Trojan Horse Plasma Wakefield Acceleration

Shift Start: 2015-05-29 14:00:00

​ Brief Summary:

First attempt of laser triggered electrons acceleration with the Trojan Horse Plasma Photocathode 
Wakefield Acceleration scheme. Found a nearly dark current (unwanted injected charge) 
free and around 10GeV energy loss regime at 10 to 13 Torr pressure in a hydrogen/helium mixture.

Experiment: E210 - Trojan Horse Plasma Wakefield Acceleration

Shift Start: 2015-05-27 20:00:00

​ Brief Summary:

The Trojan Horse lens's capability of ionizing a 27 Torr 90/10 Hydrogen/Helium-mixture has been tested.

No plasma filament was observed.

Experiment: E212 - Radiation from GeV electrons in diamond with intensities approaching the amplified radiation regime

Shift Start: 2015-05-24 12:00:00

​ Brief Summary:

Took 10,000-shot data with undulator crystal aligned, in amorph orientation, empty target holder,

and apparatus out-of the way.

Experiment: E212 - Radiation from GeV electrons in diamond with intensities approaching the amplified radiation regime

Shift Start: 2015-05-24 12:00:00

​ Brief Summary:

A bent crystal was used to study the dynamics of planar channeled electrons.
 We believe the data show experimental proof of quasichanneling of electrons which 
has not before been experimentally shown. The oscillation period is on the order of ~5µm.

Experiment: E203 - Single-shot determination of the time profile of fs long bunches by means of coherent Smith-Purcell radiation

Shift Start: 2015-05-23 13:20:00

​ Brief Summary:

A detailed study of the polarization of Smith-Purcell radiation was conducted, depending on the 
beam-grating separation. We have successfully recorded a large amount 
of data on the channels of our setup that were equipped with polarizers.

Experiment: E218 - Single-Shot Imaging of THz-Induced Switching in IT Materials

Shift Start: 2015-05-22 16:00:00

​ Brief Summary:

This experiment was designed to explore the possibilities of using the FACET CTR THz 
source to carry out pump-probe experiments on solid state samples. 
In the present state, this looks to be difficult to achieve

Experiment: E218 - Single-Shot Imaging of THz-Induced Switching in IT Materials

Shift Start: 2015-05-21 16:00:00

​ Brief Summary:

This was the first shift on THz pump on VO2 with 800 nm probe.

Experiment: E218 - Single-Shot Imaging of THz-Induced Switching in IT Materials

Shift Start: 2015-05-20 21:00:00

​ Brief Summary:

This was a checkout shift after the PAMM recovery to test the
 experimental setup for the shifts 5/21 and 5/22

Experiment: E203 - Single-shot determination of the time profile of fs long bunches by means of coherent Smith-Purcell radiation

Shift Start: 2015-05-18 21:40:00

​ Brief Summary:

The modified system was tested. The data acquisition chain is working.

Some issues with the detectors were detected which
 will be addressed during PAMM.

Experiment: E210 - Trojan Horse Plasma Wakefield Acceleration

Shift Start: 2015-05-17 16:00:00

​ Brief Summary:

The EOS diagnostic at cube 3 is a success! In preparation for Trojan horse experiment, 
the timing between the main laser, e-beam, and probe laser 
(which will be the Trojan horse injection laser) are found using the laser clocking and the delay stage.

The timing t0 for the plasma imaging is found to be 548.81 ns, with the delay stage set to -28.4 mm.

Dark current studies are performed with different beam waist position and plasma densities.

Experiment: E203 - Single-shot determination of the time profile of fs long bunches by means of coherent Smith-Purcell radiation

Shift Start: 2015-05-16 13:40:00

​ Brief Summary:

The azimuthal distribution of coherent Smith-Purcell radiation was studied at 5 different values 
of beam-grating separation. We successfully observed a dependence of
 the radiation directionality and radiation patterns on the azimuthal angle and beam position.

Experiment: E204 - Proposal for testing of metallic structures periodic structures at FACET

Shift Start: 2015-05-15 16:00:00

​ Brief Summary:

We study physics of rf breakdown in sub-THz accelerating structures. Every experiment 
we are doing something new. During this shift we characterized breakdown properties
 of CuAg, alloy that was showing superior performance in our 
X-band experiments. This was never done before at sub-THz frequencies.

Experiment: E203 - Single-shot determination of the time profile of fs long bunches by means of coherent Smith-Purcell radiation

Shift Start: 2015-05-14 13:40:00

​ Brief Summary:

We successfully tested our equipment and confirmed that it works.

We studied the intensity of the signal as function of the beam-grating
 separation and as function of the azimuthal position of the slit.

Experiment: E218 - Single-Shot Imaging of THz-Induced Switching in IT Materials

Shift Start: 2015-05-11 09:00:00

​ Brief Summary:

E218 requires a fully compressed high-charge electron beam to generate THz radiation. 
This shift tested the setup of the electron beam, characterized the THz it generated, 
and checked the THz optics, motor controls, and instruments. 
This will lead in the next shift to adding the Ti:sapphire laser to begin working 
with the full experimental setup.

Experiment: E210 - Trojan Horse Plasma Wakefield Acceleration

Shift Start: 2015-05-10 18:00:00

​ Brief Summary:

We measured and characterized the electro optic (EO) signal for two different 
crystal locations, upstream (at the IP box) and downstream (at cube1). 
The two signals were synchronized using the delay stage. 
EO signal was also obtained for longer electron bunch configuration.

Experiment: E210 - Trojan Horse Plasma Wakefield Acceleration

Shift Start: 2015-05-09 16:00:00

​ Brief Summary:

We characterized e-beam interaction with laser-induced plasma in H2/He mixture 
(90:10 ratio). We determined the amount of trapped charge for different
 plasma densities and e-beam charge.

Experiment: E201 - Wakefield Acceleration in Dielectric Structures

Shift Start: 2015-05-08 18:00:00

​ Brief Summary:

E201 continues to investigates different aspects of dielectric wakefield and THz generation
 with capillaries. Progress has been made to understand the characteristic damping of 
CCR in high field, high radiation environment.

Experiment: E217 - Ionization and down-ramp injection proposal by the E200 team

Shift Start: 2015-05-04 16:30:00

​ Brief Summary:

Too much dark current.

No energy gain in preformed plasma.

Confirm plasma oscillation wavelength is shorter at higher fill pressure

E217 solenoid is down until next PAMM on May 12.

Experiment: E213 - Temporal Limits of Electron-Phonon Interactions

Shift Start: 2015-05-04 11:00:00

​ Brief Summary:

We successfully exposed new type of samples to short bunches. We will evaluate the effect of strong electromagnetic
 field on resistive switching in samples with filamentary conductive channels. This will enable us
 to test how fast can they form, leading to improved material for resistive type of memory.

Experiment: E201 - Wakefield Acceleration in Dielectric Structures

Shift Start: 2015-05-03 16:00:00

​ Brief Summary:

A Dielectric Wakefield structure was run in a drive-witness scenario and more data was taken. 
The data taken this evening indicates gradients in excess of half a GeV/m. 
This happens to be the best data that has been collected yet.

Experiment: E210 - Trojan Horse Plasma Wakefield Acceleration

Shift Start: 2015-05-03 16:00:00

​ Brief Summary:

* We observed EO signals on all three crystals described in the goals.

* We observed EO signals on IP box EOS1 and Cube1 EOS2 at the same time by compromising the laser timing and two delay stages.
 Currently, the nominal laser timing for both EOS setups is 547.82 ns with DS1=24mm (Delay stage of EOS1) 
and DS2=-74mm (Delay stage of EOS2, shared with E224 plasma imaging delay).

Experiment: E217 - Ionization and down-ramp injection proposal by the E200 team

Shift Start: 2015-05-02 16:00:00

​ Brief Summary:

First experiment for ionization injection with the laser available for preforming a Hydrogen (H2) plasma. 
The Helium-gas (He) impurity is 
pulsed and localized to a small region of the H2. The amount of H2 and of the He impurity--the source of 
the injection electrons--was varied while the e-beam/laser alignment was tuned.

Experiment: E210 - Trojan Horse Plasma Wakefield Acceleration

Shift Start: 2015-05-02 18:30:00

​ Brief Summary:

Observed IP box EOS1 signal with 500um ZnTe crystal:

http://physics-elog.slac.stanford.edu/facetelog/show.jsp?dir=/2015/18/02...

Experiment: E201 - Wakefield Acceleration in Dielectric Structures

Shift Start: 2015-05-01 22:00:00

​ Brief Summary:

More data was taken using a driver-witness modality to study the wakefield nature of Dielectric 
Wakefield Accelerators. Additionally a filtering system was used to try and clarify previous measurements 
of Coherent Cherenkov Radiation.

Experiment: E225 - Hollow Channel Plasma Wakefield Acceleration

Shift Start: 2015-04-30 20:00:00

​ Brief Summary:

We successfully tested our optic and demonstrated that we can ionize
 hydrogen with low laser energy. We developed code to analyze raster scans on the fly.

Experiment: E204 - Proposal for testing of metallic structures periodic structures at FACET

Shift Start: 2015-04-27 15:30:00

​ Brief Summary:

We continue explore new field - properties of accelerating structures and physics of RF breakdown
 in sub-THz

frequencies. During this shift we found that the breakdown signals from 200 GHz traveling wave 
copper accelerating structure are of two different types, and the their behavior with change of 
rep-rate is different from our X-band experience.

Experiment: E210 - Trojan Horse Plasma Wakefield Acceleration

Shift Start: 2015-04-27 16:00:00

​ Brief Summary:

Very faint EO signal was observed on EOS1 using the 500 um ZnTe crystal. 
On the GaP crystal the signal was not visible.

Performed timing scan to resolve signal during post-processing.

EOS2 failed because of the dead IPOTR1 camera

No filament observed with e-beam only;Obvious filaments observed in H2/He gas mixture 
(4 Torr);Interaction enhanced when have both laser and e-beam:

Different scans were performed to characterize the e-beam interaction in the H2/He gas mixture.

Experiment: E204 - Proposal for testing of metallic structures periodic structures at FACET

Shift Start: 2015-04-25 17:00:00

​ Brief Summary:

We explore new field - properties of accelerating structures and physics of RF breakdown in 
sub-THz frequencies. During this shift we made first ever measurement of breakdown
 statistics in 200 GHz Cu traveling wave copper accelerating structure.

Experiment: E213 - Temporal Limits of Electron-Phonon Interactions

Shift Start: 2015-04-25 15:30:00

​ Brief Summary:

We successfully exposed new type of samples to short bunches. We will evaluate the effect of strong electromagnetic
 field on resistive switching in samples with filamentary conductive channels. 
This will enable us to test how fast can they form, leading to improved material for resistive type of memory.

Experiment: E200 - Multi-GeV Plasma Wakefield Acceleration Experiments

Shift Start: 2015-04-20 10:00:00

​ Brief Summary:

We ionized hydrogen with the kinoform. That's cool. 
We also did it with the axicon and observed ionization in cube 2. 
But the SAGA flashlamp is dying as we speak.

Experiment: E217 - Ionization and down-ramp injection proposal by the E200 team

Shift Start: 2015-04-19 16:00:00

​ Brief Summary:

Experiment E217, designed to produce a ultra-short and low-divergence electron bunch at 10's 
of GeV, had a "dry run" in the new Hydrogen plasma chamber. 
An upcoming run with the requisite laser preionization is coming up in a week.

Experiment: E200 - Multi-GeV Plasma Wakefield Acceleration Experiments

Shift Start: 2015-04-18 16:00:00

​ Brief Summary:

The laser still has legs. After re-locating peak compression for grating motor position
 = 19 mm, we consistently observed multi-GeV deceleration. 
Still no acceleration.

Experiment: E200 - Multi-GeV Plasma Wakefield Acceleration Experiments

Shift Start: 2015-04-17 16:00:00

​ Brief Summary:

Investigated acceleration in H2 plasma. Observed several GeV of acceleration at > 6 torr pressure,
 due to electron beam ionization. Did not observe noticable difference on the interaction
 with the laser beam on with respect to laser beam off.

Experiment: E209 - Study of the Self-Modulation of Long Lepton Bunches in Dense Plasmas and its Application to Advanced Acceleration Techniques

Shift Start: 2015-04-16 16:02:02

​ Brief Summary:

The alignment between the electron beam and the laser beam (plasma) is important when the plasma radius
 is comparable or smaller than the e-bunch radius. We tested and used a technique using beam 
position monitors downstream of the plasma to increase the number of good events to be 
considered for the data analysis (FFT of the CTRI spectrum).

Experiment: E210 - Trojan Horse Plasma Wakefield Acceleration

Shift Start: 2015-04-15 16:00:00

​ Brief Summary:

* Attempted to find t0 with plasma, but vacuum pump problems prevented 
us from being able to do anything with gas.

* Moving on, we used the last recorded t0 values and scanned a 1 ns range
 of time for both EOS systems but found no signal.

* We concluded that the polarization of the probe lasers must be incorrect 
and needs to be fixed during the next tunnel access opportunity.

Experiment: E209 - Study of the Self-Modulation of Long Lepton Bunches in Dense Plasmas and its Application to Advanced Acceleration Techniques

Shift Start: 2015-04-14 16:00:00

​ Brief Summary:

The experiment shows signs of SMI, in particular, the effects of focusing/defocusing of the beam by the SMI. 
The key measurement of the modulation period as a function of the plasma density remains close but elusive.

Experiment: E209 - Study of the Self-Modulation of Long Lepton Bunches in Dense Plasmas and its Application to Advanced Acceleration Techniques

Shift Start: 2015-04-13 14:34:00

​ Brief Summary:

Study self-modulation instability in laser-ionized, H2 plasma. 
Initial results show modification of the bunch energy spectrum and clear formation of a focused 
bunch core with charge halo around it. 
These are two of the expecting consequences of the SMI occurrence. 
However, the measurement chosen to reveal the radial modulation period, the CTR interferometry, 
yielded no significant peak in any spectrum. 
Peaks were detected in previous experiments both in lithium and argon plasmas. 
Further inquiring needed.

Experiment: E200 - Multi-GeV Plasma Wakefield Acceleration Experiments

Shift Start: 2015-04-12 16:00:00

​ Brief Summary:

We continue to move closer to two bunch operation in H2 plasmas.

Experiment: E200 - Multi-GeV Plasma Wakefield Acceleration Experiments

Shift Start: 2015-04-11 16:30:00

​ Brief Summary:

Studied electron beam and H2 plasma interaction at 1 torr, 4 torr and 8 torr. At 4 torr, stable deceleration down
 to about 4 GeV was observed
 (16 GeV energy loss), indicating that we managed to align the laser and ebeam in a way where the
 ebeam sees more than 1 m of plasma. Observed transverse instabilities 
when the ebeam was misaligned to the channel.

Experiment: E200 - Multi-GeV Plasma Wakefield Acceleration Experiments

Shift Start: 2015-04-10 18:30:00

​ Brief Summary:

Checked out new hardware installations to improve experiment stability and diagnostics. 
In particular some laser feedback systems were commissioning. 
Tested alignment methods in 4 torr H2 plasma.

Experiment: E200 - Multi-GeV Plasma Wakefield Acceleration Experiments

Shift Start: 2015-04-05 18:00:00

​ Brief Summary:

Electron beam-plasma interactions were characterized at low pressure (long plasma wavelength) continuing to 
set the stage for two bunch experiments. Specifically, the challenges presented when attempting
 to align two sub 100 um beams over a distance in excess 1m continue to be
 clarified and solutions continue to be implemented.

Experiment: E200 - Multi-GeV Plasma Wakefield Acceleration Experiments

Shift Start: 2015-04-04 16:00:00

​ Brief Summary:

Beam-plasma interaction in H2 was studies at two densitites (1 torr and 4 torr). 
Significant deceleration, large percentage of charge > 4 GeV,
 was observed at both densities.

Experiment: E200 - Multi-GeV Plasma Wakefield Acceleration Experiments

Shift Start: 2015-04-03 16:00:00

​ Brief Summary:

We showed that previous experiments were hindered by too much glass causing pulse lengthening of the laser 
and reducing intensity on target in the plasma region. Finished a good portion of the 
characterization of the plasma, in preparation for more detailed studies tomorrow night.

Experiment: E204 - Proposal for testing of metallic structures periodic structures at FACET

Shift Start: 2015-03-29 16:00:00

​ Brief Summary:

We explore new field - properties of accelerating structures and physics of 
RF breakdown in sub-THz frequencies. During this shift we made first ever measurement
 of breakdown statistics in100 GHz Cu traveling wave copper accelerating structure.

Experiment: E200 - Multi-GeV Plasma Wakefield Acceleration Experiments

Shift Start: 2015-03-28 16:00:00

​ Brief Summary:

Exciting results for beam-ionized argon. In a relative short interaction region (~10 cm), 
particles gain energy well above 30 GeV. Indicates fields are on the order of 100 GeV/m. 
The E224 plasma imaging diagnostic is being commissioned and providing valuable
 information about the plasma interaction region.

Experiment: E200 - Multi-GeV Plasma Wakefield Acceleration Experiments

Shift Start: 2015-03-27 18:00:00

​ Brief Summary:

We observed acceleration of beam electrons to 
~40 GeV in a self-ionized hydrogen plasma, as well as acceleration of trapped electrons to~10 GeV.
 We identified the region where the interaction takes place by imaging the hot plasma being produced.

Experiment: E201 - Wakefield Acceleration in Dielectric Structures

Shift Start: 2015-03-23 15:10:00

​ Brief Summary:

Studies were performed to quantify the acceleration of a witness bunch in a dieletric wakefield
 accelerator as a function of several delays between the drive-witness bunch pair. 
In addition data was taken as the bunches were scanned across the structures
 transversely as a first look into specifically exciting transverse modes in dielectric 
wakefield accelerators using two bunches.

Experiment: E210 - Trojan Horse Plasma Wakefield Acceleration

Shift Start: 2015-03-21 16:00:00

​ Brief Summary:

* Observed evidence of trapped charge in self-ionized pure Hydrogen plasma

* Performed a number of parameter scans (pressure,charge,beta*s scan,QS scan)

* Characterized the interaction

Experiment: E224 - Visualization of electron-driven plasma wakefield accelerators

Shift Start: 2015-03-20 16:00:00

​ Brief Summary:

We observed acceleration of electrons in beam ionized hydrogen > 9 GeV. 
We observed the imprint of the plasma on the E224 probe pulse.

Experiment: E201 - Wakefield Acceleration in Dielectric Structures

Shift Start: 2015-03-17 14:00:00

​ Brief Summary:

The shift goal was to measure acceleration in a dielectric structure using a drive-witness modality. 
There was also the goal of examining low charge, short bunch phenomenon related to the extremely
 intense beams present at FACET. Data was collected for the two bunch scenario and shows promise. 
The low charge modality we used in one and two bunch configurations and yielded interesting results. 
We measured an accelerating gradient of 170 MeV/m.

Experiment: E200 - Multi-GeV Plasma Wakefield Acceleration Experiments

Shift Start: 2015-03-15 16:00:00

​ Brief Summary:

* Documented laser before and after shift.

* Attempted form a plasma in hydrogen with the laser, but failed.

* Tried adjusting grating separation to find optimal compression, but still could not make a plasma with the laser.

* Determined that most likely cause of failure is the damaged window between
 the compressor and the IP box, based on our observations.

Experiment: E201 - Wakefield Acceleration in Dielectric Structures

Shift Start: 2015-03-14 20:00:00

​ Brief Summary:

E201 experiment continues to look at dielectric tubes in various diagnostics 
such as CCR, acceleration/deceleration, and etc.. This shift focuses on 10cm long tube.

Experiment: E201 - Wakefield Acceleration in Dielectric Structures

Shift Start: 2015-03-13 15:17:00

​ Brief Summary:

E201 experiment continues to investigate THz radiation from dielectric tubes. Diagnostics were performed to
 identify the CCR modes generated and the duration of the modes. Experiment will
 proceed to much longer tube with goals of seeing acceleration/deceleration and
 determining how much energy is carried by the THz radiation.

Experiment: E225 - Hollow Channel Plasma Wakefield Acceleration

Shift Start: 2015-03-12 18:00:00

​ Brief Summary:

Tried to ionize hydrogen with the kinoform. We did not.

Experiment: E200 - Multi-GeV Plasma Wakefield Acceleration Experiments

Shift Start: 2015-03-12 17:00:00

​ Brief Summary:

Improved software for automatically changing hydrogen pressure was tested.

Experiment: E201 - Wakefield Acceleration in Dielectric Structures

Shift Start: 2015-03-12 16:00:00

​ Brief Summary:

To ensure the success of future work the electronics used for data collection
 in the E201 project were checked and found to be working to specifications.

Experiment: E200 - Multi-GeV Plasma Wakefield Acceleration Experiments

Shift Start: 2015-03-20 02:00:00

​ Brief Summary:

Tested a new type of feedback for tracking and predicting bunch profiles.

Experiment: E200 - Multi-GeV Plasma Wakefield Acceleration Experiments

Shift Start: 2015-03-08 16:00:00

​ Brief Summary:

* Performed numerous laser alignment scans with the axicon position, including 2-D raster scans.

* Were able to find point of best interaction to within ~50 um.

* Were not able to observe deceleration; only transverse effects on e-beam from plasma interaction.

Experiment: E200 - Multi-GeV Plasma Wakefield Acceleration Experiments

Shift Start: 2015-03-07 16:00:00

​ Brief Summary:

The laser-electron beam timing for best interaction was confirmed to be stable day-to-day
 and the extent of the plasma-beam overlap was measured to be 200-400um in the hydrogen plasma 
created by the 0.75 degree axicon.

Experiment: E225 - Hollow Channel Plasma Wakefield Acceleration

Shift Start: 2015-03-06 18:00:00

​ Brief Summary:

Tried to ionize hydrogen with the kinoform. Went up to 15 Torr but did not see 
significant interaction. Did see interaction with axicon. Kinda a bummer. When will I graduate?

Experiment: E210 - Trojan Horse Plasma Wakefield Acceleration

Shift Start: 2015-03-04 18:30:00

​ Brief Summary:

Observed EOS signal, and it still appears as a shadow despite removing the pellicle beam splitter. 
That's not necessarily a bad thing in and of itself, 
just surprising. What was surprising and bad was that it appeared the EOS probe laser 
was apertured in the tunnel, either by a closed iris, blockage by a foreign object, or a bumped mirror.

Experiment: E213 - Temporal Limits of Electron-Phonon Interactions

Shift Start: 2015-03-04 16:00:00

​ Brief Summary:

Goals for the shift were achieved. We exposed new type of samples to short bunches to evaluate the effect of strong 
electromagnetic field on resistive and magnetic switching. The new structures will remove the the 
effect of edge electric fields in the patch antenna structure.

Experiment: E200 - Multi-GeV Plasma Wakefield Acceleration Experiments

Shift Start: 2015-03-01 20:30:00

​ Brief Summary:

We got through some of our laser-to-electron beam spatial and temporal alignment checks. 
Some progress was made in understanding the tolerance of the alignment in time and space, 
though the results seem more sensitive than that observed two nights ago. 
Next shift can build upon what we've learned so far.

Experiment: E210 - Trojan Horse Plasma Wakefield Acceleration

Shift Start: 2015-03-01 16:00:00

​ Brief Summary:

We succeed in taking all the data we need for EOS check out and diagnostics 
looks working very well, next step is to build an analysis tools and incorporate
 this diagnostics into regular data taking.

Experiment: E200 - Multi-GeV Plasma Wakefield Acceleration Experiments

Shift Start: 2015-02-28 16:00:00

​ Brief Summary:

We observed a strong interaction with the laser off on >50% of the shots. 
Laser on interaction was finicky. E224 did not observe signal. We learned lots.

Experiment: E200 - Multi-GeV Plasma Wakefield Acceleration Experiments

Shift Start: 2015-02-27 22:00:00

​ Brief Summary:

Successfully re-established H2 plasma aligned to beam. Did optimization of interaction vs transverse 
alignment and timing. Observed several GeV deceleration and 
some acceleration. Commissioned new optics functions for spectrometer.

Experiment: E210 - Trojan Horse Plasma Wakefield Acceleration

Shift Start: 2015-02-27 17:00:00

​ Brief Summary:

Very successful checkout shift for EOS. A very clean signal was seen with both crystals, 
and the signal width clearly changed with the e-beam phase (i.e. with the e-beam bunch length). 
We had trouble with the TCAV and the GUI, so ran out of time before we could complete 
our full battery of datasets that we had planned. Nonetheless, this shift has shown 
there is great promise in this new diagnostic tool!

Experiment: E200 - Multi-GeV Plasma Wakefield Acceleration Experiments

Shift Start: 2015-02-26 20:30:00

​ Brief Summary:

Verified operation of a new spectrometer screen (wide Lanex screen).
 Screen works. Varied spectrometer magnet settings,
 and studied the effect on the beam.

Experiment: E200 - Multi-GeV Plasma Wakefield Acceleration Experiments

Shift Start: 2015-02-23 14:00:00

​ Brief Summary:

Performed experimental checkouts of hydrogen and laser systems for E200. 
Checkouts were completed, and we were delightfully surprised to find that most 
were in even better shape than we had hoped in terms of laser alignment and 
effort required to make the systems work.

Experiment: E200 - Multi-GeV Plasma Wakefield Acceleration Experiments

Shift Start: 2015-02-20 19:00:00

​ Brief Summary:

Studied Chromaticity in spectrometer with new optics.
 Measured optics compare well with model, indicating an
 improvement of spectrometer chromaticity.

Experiment: E200 - Multi-GeV Plasma Wakefield Acceleration Experiments

Shift Start: 2015-02-19 21:00:00

​ Brief Summary:

There appears to be some nonlinear dispersion on the SYAG screen. 
This causes the set_slit.m function to not work properly, which
 means no tomography was performed.