Experiment 09069 in Progress

Experiment 09069 ( Measurement of Excitation Energy of Neon Prefragments) is under way at the NSCL. The experiment seeks to measure evaporation neutrons in coincidence with residue projectile fragments to determine the excitation energy of the intermediate fragments produced in the reactions.  A Mg-32 beam is being  used to create neon isotopes that are measured by the Sweeper Magnet and charged particle detectors while the associated distribution of evaporation neutrons is measured using the MoNA detector.  Michele Mosby is the spokesperson for the experiment.

Reconfiguration of MoNA

While reconfiguring MoNA for an upcoming experiment, the students found out just how many cables there are!

Q: How long are all MoNA cables (signal and high-voltage) combined?

(A) 8075 m
(B) 5 miles
(C) as long as the Mackinac Bridge

If you know the answer, write it on a card, attach it to a CAEN V977 I/O register with fully programmable RORA interrupter and individual channel enabling/disabling, and mail it to
1 Cyclotron, East Lansing, MI 48824.

MoNA reconfigured: the modular array was split and detector modules were placed side-by-side in order to achieve a larger angular coverage.

LISA bar attenuation measurement - Westmont College

Using a 60Co source we measured the spectral location of the 60Co Compton edge as a function of source position along the LISA bar in order to measure the light attenuation. Below are the results for each PMT. Since the total attenuation is dependent on both bulk properties of the material and on the internal reflection profile, the first two points in each plot (i.e those closest to the PMT's) were eliminated from the exponential fits in order to obtain better agreement. The resulting attenuation length for the LISA bar is approximately 5.8 m, in very good agreement with that of the MoNA bars.

First Light - LISA detector spectra from Westmont College

At Westmont College we've recently complete assembly of our first LISA detector. Pictured below are cosmic muon energy spectra for each PMT, the position spectrum corresponding to the distribution of muons passing through the bar as a function of length, and one of the two detector ends. The position spectrum gate, calculated from the light arrival time difference between the two PMTs, consisted of the AND signal between the two muon peaks.




On another LISA related front, Lewis Elliott and Phil Kasavan are pictured working on the inverter box front panels.

LISA Bars at Concordia

The scintillation bars continue to arrive at colleges in the MoNA collaboration. The crates containing the 16 bars for Concordia College where delivered today.

First LISA Bars arrive

The first set of LISA scintillation bars arrived at Westmont College today. The sixteen 2 meter long by 10 cm square bars of scintillation material will form the core of a set of neutron detectors that will be constructed, tested and calibrated at Westmont by undergraduate students. Nine other schools will also build a layer of neutron detector modules for LISA.

Experiment 09040 in Progress

Experiment 09040: "Study of Neutron Unbound States in 28F" is underway at the NSCL. A Ne-29 secondary beam is being used to create 28F via one proton stripping at the target. MoNA detects the outgoing neutron, the sweeper collects data on the charged fragment and CAESAR measures the gamma-rays. With this information the original 28F state can be reconstructed. This is the first time that that CAESAR has been used in conjunction with the MoNA-sweeper system. The PI for the experiment is Dr. Nathan Frank from Augustana College.