E-201

Shift Request:

One shift is 8 hours long. There are three shifts per day- owl (midnight-8am), day (8am-4pm) and swing (4pm-midnight).

Switching beam configurations can take a few hours so if multiple configurations are included in your run-plan, the time should be accounted for in your request.

To minimize time spent changing configurations, we prefer to block shifts together as changing from one experiment to another typically involves a configuration change that takes time away from doing science.

Number of shifts requested: / 60+
Preference for number of shifts in a single continuous block: / 15
Preference for time between blocks of shifts: / 2 weeks

Beam Request:

Halo: We will provide a phosphor screen on which we can see the beam halo and will need to reduce halo as much as possible.

Parameter / Request 1 – low charge for CCR spectroscopy. / Request 2 – low charge with variable bunch length
Location of waist (e.g. centre of apparatus) / Kraken (new chamber) / Kraken (new chamber)
Transverse spot size (σxxσy) in microns / (30,30) or below. As round as possible. / (30,30)or below. As round as possible.
Bunch length (σz) in microns / 200
Note that two-horned structures are not ideal- we prefer Gaussian. We will look at the effects of different structures through simulations to get an idea of our tolerance. TCAV measurements would be required. / Variable 200um-50um in 25um steps.
Charge (e-/bunch) / ~400pC / ~400pC
Beta_x, Beta_y (or length of structure at IP) / 1cm structures therefore waist is >1cm / 1cm structures therefore waist is >1cm
Tolerable jitter (specify parameter- e.g. position jitter) / σz< 10%
(σxxσy) < 10%
The ID of the smallest fibers we want to test is 100um. (though we have some larger aperture structures of lesser interest if this cannot be met). We request jittering bunch is contained within this. / σz< 10%
(σxxσy) < 10%
The ID of the smallest fibers we want to test is 100um. (though we have some larger aperture structures of lesser interest if this cannot be met). We request jittering bunch is contained within this.
Beam Rate / 1Hz / 1Hz
Time spent at config (eg 10 minutes, 4 hours, 2 days etc) / 15 minutes per scan. We then change samples (assume we have 12 samples). In total, that is ~4 hours at this single beam config (ideal time with working diagnostics and stated beam parameters). / As before,15 minutes scan per sample per config. ~24 hours total.
Additional Comments / This is an initial check-out with parameters close to those at ATF where we know the fibers survive. Charge and bunch length can be traded off (if the charge is >1nC, we’d be able to run by having longer bunches for example). / Bunch length variable from 200-50 (25um steps). We’re decreasing bunch length to watch the increase in CCR signal and potentially a breakdown. An alternative to changing bunch length would be to change the charge incrementally. As in request 1, we are fine with a higher charge than 400pC but then we’d need longer bunch lengths.
Parameter / Request 3 – Flat beam for planar structure CCR spect. / Request 4 – Flat beam, variable width
Location of waist (e.g. centre of apparatus) / Kraken / Kraken
Transverse spot size (σxxσy) in microns / (300,30)
or below.10:1 ratio between x and y. / (600,30) - (30,30)
σx variable from 600um – 30um (~50um steps)
Bunch length (σz) in microns / 200 / 200
Charge (e-/bunch) / 400pC / 400pC
Beta_x, Beta_y (or length of structure at IP) / 1cm structures therefore waist is >1cm / 1cm structures therefore waist is >1cm
Tolerable jitter (specify parameter- e.g. position jitter) / σz< 10%
(σxxσy) < 10%
The ID of the smallest fibers we want to test is 100um. (though we have some larger aperture structures of lesser interest if this cannot be met). We request jittering bunch is contained within this. / σz< 10%
(σxxσy) < 10%
The ID of the smallest fibers we want to test is 100um. (though we have some larger aperture structures of lesser interest if this cannot be met). We request jittering bunch is contained within this.
Beam Rate / 1Hz / 1Hz
Time spent at config (eg 10 minutes, 4 hours, 2 days etc) / 15 minutes for a scan. Then we move to the next slab. Possibly 4 hours for all slabs mounted. / 15 minutes for a scan. Then we move to the next slab. Will need to do a scan for each slab at each transverse spot size - estimate 24 hours in total.
Additional Comments / This is an initial check-out with parameters close to those at ATF where we know the slabs survive. Charge and bunch length can be traded off (if the charge is >1nC, we’d be able to run by having longer bunches for example). / Bunch transverse size in x variable from 600-30 (50um steps). We’re watching the CCR signal at each setting. As in request 1, we are fine with a higher charge than 400pC but then we’d need longer bunch lengths.
Parameter / Request 5 - Variable bunch length for breakdown
Location of waist (e.g. centre of apparatus) / Kraken (DWA)
Transverse spot size (σxxσy) in microns / (30,30) or below. As round as possible.
Bunch length (σz) in microns / 25-200
Bunch length variable from 200-25 (25um steps)
Charge (e-/bunch) / 3nC
Energy spread
Beta_x, Beta_y (or length of structure at IP) / 1cm structures therefore waist is >1cm
Tolerable jitter (specify parameter- e.g. position jitter) / σz< 10%
(σxxσy) < 10%
The ID of the smallest fibers we want to test is 100um. (though we have some larger aperture structures of lesser interest if this cannot be met). We request jittering bunch is contained within this.
Beam Rate / 1Hz
Time spent at config (eg 10 minutes, 4 hours, 2 days etc) / 15 minutes per sample per bunch length setting. ~12 samples so 24 hours.
Additional Comments / We will be purposefully breaking down the fibers by decreasing the bunch length at high charge and taking data until a breakdown occurs.