DU Run

Angular dependence [math](\theta,\phi)[/math] of two neutrons emitted from DU target was determined.

The [math]\theta[/math] angle was measured as shown below in the picture:

The target was considered to be the point.

The X-coordinate of the neutron hit of each detector was determined from the TDC difference spectra with application of real calibration factors obtained in separate experiment with Co-60 source. As an example of the cuts applied see the plot below:

The data from the current run 4118 are plotted below:

The timing cuts were applied for TDC sum spectra. It should be noticed that time cuts included both neutron and photon areas because in four fold coincidences the photon accidentals will dissappear.

In the case of Det K it was hard to observe the neutron area and the TDC singles spectra were used to set the time cut (see Det K data on the plot below):

After writing a bunch of scripts the root file was created and the data are plotted below:

In order to see better [math]\theta[/math] and [math]\phi[/math] distributions it was created a couple of plots with corresponding projections:

[math]\theta[/math] projection of the 3D plot

[math]\phi[/math] projection of the 3D plot

The uncertainties on the [math]\phi[/math] angle are determined by the width of the neutron detectors and the distance from the target.

The uncertainties on the [math]\theta[/math] angle are determined by the width of the TDC difference spectra. Should be discussed.