Measurements of vertical distances between wire and cathode 03/12/2003


In order to find all possible causes of the bad functioning of the LST studied before (for more details see mapping of profile 1, profile 2 and the pictures of open profile.), here we show the vertical distances between wire and cathode measured with an optical microscope (50x). Moving the microscope we focus before the wire and after the cathode, this distance is the distance between wire and cathode. We have measured these distances about every 5 cm along the cell for all wires of the HR profile 1. In following plots we report the performed measurements.

  • The errors on the measurement of the height to focus the wire is about 0.005 mm.
  • The errors on the measurement of the height to focus the grafite is about 0.005 mm.
  • Than the errors on the distance between wire and grafite is 0.01 mm.
  • In following plot we used an overestimated errors for the distances of 0.05 mm.
  • These measurements has been performed with the layer on a granite plane and with some little weight on each bridge.

  • Profile 2











    From the above measurements we note that near the bridges the distances are not always equal to 4.5 mm, as it should be. This thing seems stange, because one thinks that the bridge is a precise fusion, but the bridges used in these profiles have been modified. Probably after the modification the bridges are not so precise, infact cutting a profile and looking at the bridge some imperfections are evidents: inside certain cells the bridge has a little inclination and we observed by eyes different heights for bridge in different cells. Here we show a picture of one bridge.

  • See the correlation between heights and rate for this profile.



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