First K2K neutrino event at Super-Kamiokande

These are the images of the first neutrino event from K2K beam seen in Super-Kamiokande detector.

The color scale is residuals (time of flight subtracted hit times) with 876 ns range, every bin 29.2 ns wide (first and last bins are overflow bins). Size corresponds to observed charge. Cherenkov cones of tracks are outlined, diamonds mark projected exit points, '+' mark projected entry points (i.e. pointing track backwards). Also on the perspective images 200 cm long lines are drawn from vertex along each track direction. 'X' signs mark projected vertex on top, bottom and side walls. K2K beam exit point from the vertex is marked with 'K', entry point is marked with inverted (mirror image) 'K'. Outer detector (anti-coincidence) is shown in the small inset. Fuzzy electron ring from muon decay electron is visible in orange (later time).

Unrolled view:

Perspective view:

Close-up:

You will need red-and-blue glasses to see the following image stereographically. Blue filter should be on your right eye. I used -grayscale option in tscan to make two black and white images. Then I used gimp to combine them.

You don't need red and blue glasses to view the following stereo images. You just have to be able to cross your eyes. This is called "free viewing" (free of special 3D glasses).

To make it easier don't sit too close to the monitor, the image is too big for this. Put your finger between the image and your eyes, close to your eyes. Look at the finger. Put it at such distance that the background SK image blends into 3 images, the middle one is the stereo image. It is blurred as long as you focus on your finger. Now the most difficult part. Try to focus on the SK image without uncrossing your eyes. It may take a few minutes to learn to do it.

Black and white version for print in a newspaper.

How these images were made

Back to tscan.


Tomasz Barszczak