Delivery to TIGRESS ended this morning as scheduled. ICR took nice emittance scans and is completing a target snapshot now. Canister still at -22"Hg and MCIS at 7.3e-8 Torr.

Chance to snap some wirescans. Attached.

Delivery of 15N4+ to TIGRESS continues. Source gas canister is still at ~-22"Hg, and MCIS pressure is 7.2e-8 Torr. ICR reported intensity drops a couple of times this morning. The attached Stripchart suggests beam from the source is down to about a third from status quo. We will look into it now.

Delivery to TIGRESS began yesterday or so. ICR reported beam intensity drops overnight. I'll look at it presently. Meanwhile, canister pressure is still ~-22"Hg and MCIS pressure is 7.09e-8 Torr.

Later... Check source at request of ICR. It looks mighty fine. Slight tweaks on RF, but really no great change. FC6 was and is 200enA, though it was around 80enA this morning.

Setup into ISAC-II began last night. Tuning is in progress now. Beam on FC6 overnight. Canister pressure is -22"Hg and MCIS pressure=7.1e-8 Torr. Pressure showed correlation with temperature. It is overcast today and cool, suggesting a fairly flat response today.

User tuning began Sunday night. Beam physics expert chose to retire the IOS:Q1 defeat, as he did not know until yesterday that it existed. He discovered it after attempting to retune yesterday around noon from scratch and making a mess, notwithstanding Keerthi's clear instruction to leave it alone. He also does not know that Rick developed a tune for this, which provides cleaner transmission than the "book" tune. Pity. Presently there are some 75enA of beam at FC6. That should be enough. Note that there were some 90enA with the "defeat" tune in place, prior to changing the IOS tune. Canister is at ~-22"Hg, and MCIS pressure at ~7.0e-8 Torr at ~09:00.. ICR is tuning through presently.

Keerthi set up the Supernanogan for 15N operation and destined for TIGRESS, using two source gas options: a miniature bottle of enriched 15N2 and a canister with a charge of research-grade 14N2. The canister is similar to the one we used for the 33S run to DRAGON, which finished Saturday morning. Canister is at -22"Hg and MCIS at 7.27e-8 Torr. A couple of beam stability tests were conducted at 15N4+ and 15N6+. Bob can choose which one he prefers to use. 15N4+ is selected and tuned through IOS up to the RFQ presently (~10:30 am).

Later... Bob reported at the Beam Delivery meeting that the 33S6+ beam was a very nice beam. We appreciate hearing it.

Delivery of 33S6+ continues to DRAGON for the final day. Some online tuning of the line overnight. Source gas canister pressure remains at ~-20"Hg, and MCIS pressure is at 7.1e-8 Torr.

33S6+ delivery to DRAGON continues until Saturday morning. All the signs are that beam is excellent. Source gas canister is still at ~-20"Hg, and MCIS vacuum is at 7.0e-8 Torr.

33S6+ delivery to DRAGON continues. It is Maintenance Day for everybody else today. Source gas canister pressure = -20"Hg. MCIS pressure = 7.7e-8 Torr.

33S6+ delivery to DRAGON continues. Looks like there was an RF tweak overnight. Source gas canister still at ~-20"Hg. MCIS vacuum at 7.4e-8 Torr.

Delivery of 33S6+ to DRAGON continues. A couple of RF tweaks done over the weekend. Source gas canister pressure at -20"Hg. MCIS pressure at 7.3e-8 Torr. At this rate, we could deliver 33S until approximately forever.

Beam tuning in progress. Source gas canister at -20"Hg. MCIS pressure at 7.62e-8 Torr.

33S on FC6 overnight. Preparing to send beam to DRAGON now, and confirm isotope.

Source gas pressure gauge on canister = -20"Hg. MCIS pressure = 7.8e-8 Torr.

Some 3enA of beam on FC6 presently. Let it sit.

33S spectrum is saved as 33S_spectrum.dat 

after 24 hours background spectrum saved as "BackgroungNo33S003.dat"

RF Amplitude :7.767 , RFoutput power= 5W, Output power (dB)=36.4

after 24 hours background spectrum saved as "BackgroungNo33S002.dat"

RF Amplitude :1.553 , RFoutput power= 0, Output power (dB)=0  

Tried to see the background before 33S installation. Found few problems: MCIS:YCB1 does not hold more than 58V.

Very difficult to transport the beam without YCB1. Need to find a solution. Open and fix it is not an option even though we have a ready spare. It will take two weeks to get the vacuum back.

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Outgoing TIGRESS experiment was the occasion for another ISAC milestone, 8MeV/u through the SCC for the first time just around midnight last Friday, May 21st. This also represented the first 8MeV/u beam to an experiment. And we can proudly say that OLIS beam was used. TIGRESS run ended at 08:30 as scheduled. Attached is a trar graph of beam on FC6, snapped periodically throughout the run. As before, you can see a small daily variation likely related to temperature of NA-LCW. There were reports of HPL tests this past Thursday and Friday. Evidently no effect over here.

ISAC-I tuning done yesterday. TBC today into ISAC-II. Beam very nice overnight.