found to be:
n=n0-0.0005(T-20) where T is freon temperature in degrees Celsius
n0=Sqrt(1+ 0.554*lamda^2/(lamda^2-5796)) where lamda is photon wavelength in nm taken at 20 degrees Celsius
-Preliminary, the parametrization itself is considered to be permanent one. The only parameter to store and retrieve is freon temperature. Since this value is available from
-DCS DB and expected to be served by a SHUTTLE program which is not yet ready, the following temporarily solution has been adopted.
+Preliminary, the parametrization of refractive index versus temperature and photon energy is considered to be permanent.
+As the reconstruction itself is only interested in mean refractive index Nmean C6F14, the most elegant solution is to store in OCDB this value, prcalculated in
+AliHMPIDPrecprocessor. 2 measurements of temperature is avaiable from DCS: for inlet and outlet. They come in form of TObjArray of AliDCSValue, where AliDCSValue
+holds the value of temperature plus a time stamp at wich the value was taken. Due to organization of DCS, it's not possible to implay that all the points are taken at the same
+time, hence marked with the same time stamp. So the mean temperature are not calculable from inlet-outlet pair. Instead each sperate temperature data points are fitted.
+The resulting functions provide mean temperature function.
+
+
+
In local CDB storage (default directory is $ALICE_ROOT) two versions of freon refractive index are written by external macro RichCdb.C :
Run0_0_v0_s0.root contains DiMauro's parametrization and the temperature is set to 20 degrees. To be used as default for simulation and reconstruction.
Run0_0_v0_s1.root contains DiMauro's parametrization and the temperature is set to 50 degrees. To be used in special uncalibrated reconstruction to test calibration procedure.
-0.942641 0.000000 0.333807 Tz = 163.565361
-Map of all HMPID PC planes, coordinates are in spherical system= distance from IP in cm, Theta and Phi in degrees:
-_______________________________ _______________________________
-| 506.21 506.21| | 506.21 506.21|
-| 63.26 78.07| | 82.59 97.41|
-| 58.02 57.32| | 57.22 57.22|
-| | | |
-| 498.00 | | 498.00 | Sensitive area (130.60,126.16)
-| 70.50 | | 90.00 | Lors Center ( 65.30, 63.08)
-| 50.00 | | 50.00 |
-| | | |
-| 506.21 506.21| | 506.21 506.21|
-| 63.26 78.07| | 82.59 97.41|
-| 41.98 6 42.68| | 42.78 5 42.78|
-------------------------------- -------------------------------
-
-_______________________________ _______________________________ _______________________________
-| 506.21 506.21| | 506.21 506.21| | 506.21 506.21|
-| 63.26 78.07| | 82.59 97.41| | 101.93 116.74|
-| 38.02 37.32| | 37.22 37.22| | 37.32 38.02|
-| | | | | |
-| 498.00 | | 498.00 | | 498.00 |
-| 70.50 | | 90.00 | | 109.50 |
-| 30.00 | | 30.00 | | 30.00 |
-| | | | | |
-| 506.21 506.21| | 506.21 506.21| | 506.21 506.21|
-| 63.26 78.07| | 82.59 97.41| | 101.93 116.74|
-| 21.98 4 22.68| | 22.78 3 22.78| | 37.32 2 38.02|
-------------------------------- ------------------------------- -------------------------------
-
- _______________________________ _______________________________
- | 506.21 506.21| | 506.21 506.21|
- | 82.59 97.41| | 101.93 116.74|
- | 17.22 17.22| | 17.32 18.02|
- | | | |
- | 498.00 | | 498.00 |
- | 90.00 | | 109.50 |
- | 10.00 | | 10.00 |
- | | | |
- | 506.21 506.21| | 506.21 506.21|
- | 82.59 97.41| | 101.93 116.74|
- | 2.78 1 2.78| | 2.68 0 1.98|
- ------------------------------- -------------------------------
+
+
+
+
+
+
+
git://git.uio.no / u / mrichter / AliRoot.git / blobdiff