It's amazing to think about how far we've come since April 2024.
One year ago this month, we were given the go-ahead to begin commissioning the new APS storage ring. Electrons circulated for the first time on April 14, and we demonstrated the first successful multi-bunch swap-out injection near the end of the month. Everything since then, from setting a world record for low electron beam emittance to bringing dozens of beamlines into operation, has happened in just 12 months.
The milestones keep coming, too. Last month we reported that we achieved our full design current of 200 milliamps (mA) and, now that we're here, we have measured the horizontal emittance of the electron beam at the full current. I'm pleased to report that the emittance is even smaller than our previous world record: 33 picometers radians (pm.rad). This result is another indication that the upgraded APS is delivering the brightest synchrotron X-ray beams for research in the world.
Last month, the APS celebrated 30 years since the original first light, and we firmly believe the best is yet to come.
We're nearing the end of our second user run of the upgraded APS era, and with 38 of our beamlines accepting users for early experiments (as you can see in the beamline progress chart below), the experiment floor has been a busy place. Below are some photos of users conducting research at our beamlines, essentially "kicking the tires" of the new machine and exploring the new capabilities, along with students touring a University of Chicago beamline as part of the eBERlight initiative.
At the end of April, the APS will ramp down for our planned spring maintenance period, bringing this user run to a close. We'll be back to normal user operations in June with a switch to timing mode after the July 4 holiday. For more information on submitting proposals and reserving time with the upgraded APS X-ray beams, please visit the user office page.
Early next month (May 5-9) we will host the 2025 APS/CNM Users Meeting. If you have registered and will be attending, we're looking forward to seeing you.
One last thing: If you haven't seen this video that traces the entire 720-foot-long new X-ray feature beamline for the In Situ Nanoprobe, well, you should. It gives a true sense of the scale of these extraordinary beamlines we have built to address the world's most pressing scientific problems.
Until next month, be safe and be well.
Sincerely,
Jonathan Lang
Director, X-ray Science Division