Happy 2nd Birthday, LBNF!

The first engineering sketch of LBNF’s Far Site underground campus

As the clock struck 4:55 p.m. in Batavia, IL on January 8, 2015, after a 2014 buzzing with talk about combining LBNE and LBNO, then-LBNE Project Director Jim Strait and Project Manager Elaine McCluskey declared the end of LBNE. Anything LBNE-related that was to continue to evolve into an international project and experiment would henceforth be known as the LBNF project — and a to-be-determined experiment name, which started off as the unlovely “ELBNF.”

Later that January ELBNF held its first, and only, collaboration meeting. (By the meeting the following April, the experiment had been christened “DUNE.”) Momentum picked up. Early that February, the former LBNE and LBNO project staffs held their first face-to-face meeting — a “Geotech-Cryo Risk-Cost” workshop at Brookhaven — to come up with a workable design concept for the 40-kiloton underground detector.

Interrupted by an ice storm that closed the lab mid-day February 3rd, but undeterred, the group resumed that afternoon at a meeting room in a nearby hotel, then again the next morning at the reopened lab. They adjourned around lunchtime, before completely resolving the primary assumptions that would guide the layout and strategy of achieving a 40-kiloton liquid argon detector.

After lunch and after some participants had left for the airport, Marzio Nessi collected the remaining few, David Lissauer, Elaine McCluskey and Tracy Lundin, in Brookhaven’s cafeteria — still nearly deserted due to the previous day’s ice storm – to finish the business at hand. He had one large piece of paper. Within an hour or so the group had sketched out a basic layout of the underground detector spaces, a layout that would evolve into the current configuration of the LBNF far site conventional facilities and cryostats for DUNE.

Who, when, and “the room where it happened” (detail from lower right corner of paper)

“Marzio wanted to figure it out then and there. He is really a ‘doer,’ ” said McCluskey. “Here are my notes from his summary: ‘2 intense days. 1 type of cryostat at 10kt module. Can use one cryostat design for all technologies. Rectangular is ok. Need 2 cryostats operational before filling 1st one.’ From this point, it only took three more meetings in the space of a month to really set the configuration and the strategy for constructing the facilities and the cryostats.“

A reproduction of that original piece of paper now hangs in current LBNF Project Director Chris Mossey’s office. Upon careful inspection, it reveals evidence that these project veterans reckoned with many critical aspects of the project that very afternoon — alternative layouts, ventilation, rock mechanics, equipment installation access, a beneficial occupancy strategy, and even a document approval process.

It also bears two hallmarks of a worthy engineering sketch — a north arrow and an indication of scale (in this case, “NTS” for “not to scale”).

Marzio Nessi (CERN), David Lissauer (BNL), and Elaine McCluskey and Tracy Lundin (Fermilab)