<html><body><div style="font-family: tahoma,new york,times,serif; font-size: 14pt; color: #009900"><div>good work tyler.<br></div><div>w.r.t. line #8: (see below, i reformatted your e-mail), i don't see any highlighting in the excel sheet. </div><div>don't understand where you come up with the <1% error you quo<span id="transmark" style="display: none; width: 0px; height: 0px;"></span>te? <br data-mce-bogus="1"></div><div><br data-mce-bogus="1"></div><div>fix your significant figures, do let excel decide!<br data-mce-bogus="1"></div><div><br data-mce-bogus="1"></div><div>w.r.t. line #13: perhaps initially the calibration may be dependent (you didn't take a measurement as soon as you turned it on, did you?), but once the lamp has warmed up, the calibration doesn't change.<br data-mce-bogus="1"></div><div><br data-mce-bogus="1"></div><div>finally, calculate the confidence level of your measurement.<br data-mce-bogus="1"></div><div><br data-mce-bogus="1"></div><div>amrit<br data-mce-bogus="1"></div><div><br data-mce-bogus="1"></div><div><span style="display: none; width: 0px; height: 0px;">am<br data-mce-bogus="1"></span></div><div><span style="display: none; width: 0px; height: 0px;"><br data-mce-bogus="1"></span></div><div><br data-mce-bogus="1"></div><div><span style="display: none; width: 0px; height: 0px;">w.r.t. #13<br data-mce-bogus="1"></span></div><div><br></div><hr id="zwchr" data-marker="__DIVIDER__"><div data-marker="__HEADERS__"><b>From: </b>"Tyler Lemon" <tlemon@jlab.org><br><b>To: </b>"dsg-rich" <dsg-rich@jlab.org><br><b>Sent: </b>Tuesday, July 18, 2017 4:43:39 PM<br><b>Subject: </b>[Dsg-rich] RICH - reflectivity test station calibration stability results<br></div><div><br></div><div data-marker="__QUOTED_TEXT__"><div style="font-family: times new roman,new york,times,serif; font-size: 12pt; color: #000000" data-mce-style="font-family: times new roman,new york,times,serif; font-size: 12pt; color: #000000;"><div>Hello Marco Mirazita,<br></div><br><ol style="list-style-type: undefined;"><li><span style="background-color: rgb(255, 255, 0); color: rgb(0, 0, 0);" data-mce-style="background-color: #ffff00; color: #000000;"><span style="background-color: rgb(255, 255, 255);" data-mce-style="background-color: #ffffff;">Attached</span></span> in "<em>2017-07-18_calibration_stability_tests.xlsx</em>" are the results from today's calibration stability of the reflectivity test station. </li><li>In the Excel sheet, there is a table of all the raw data for the calibration runs. </li><li>At the end of the data, there are statistics for the data.<br></li><li>For the<span style="background-color: rgb(255, 255, 255);" data-mce-style="background-color: #ffffff;"> stability test,</span> we turned on the lamp source at 8:00AM to allow it to heat up. </li><li>We aligned the test station's optics for a calibration run and took data on every hour starting at 10:00AM until 4:00PM (total of seven calibration runs). </li><li>After the initial alignment, the dark box was not opened and the position of the photodiodes was not changed.<br></li><li>The results support that the<span style="background-color: rgb(255, 255, 255);" data-mce-style="background-color: #ffffff;"> calibration measurements do not vary over the course of a few hours </span>if the test set-up is not modified in any way.</li><li><span style="background-color: rgb(255, 255, 0);" data-mce-style="background-color: #ffff00;">The calibrations for each wavelength has a calculated error of less than 1%, with the exception of the 300nm wavelenth (highlighted in yellow).</span></li><li>The 300nm-wavelength calibration results from 10:00AM are also highlighted in yellow. This measurement seems to be the source of the larger error for the 300nm wavelength calibration. <br></li><li>Also attached in "<em>all_calibrations.xlsx</em>" is data for all calibrations we used for all reflectivity tests, including the ones from today.</li><li>The data is arranged in the same way as the stability test results with statistics at the end.</li><li>Using all calibration run data, the calculated error of the calibration is much higher (~10% to ~17%). This most likely is due to the realignment that takes place between calibrations and between the testing of mirrors. <br></li><li>In conclusion, the calibration does not seem to depend on the amount of time the lamp source is on. </li><li>Using the data from all calibrations, the main source of error appears to be the realignment of test station optics.<br></li></ol><br><div>Best regards,<br></div><div>Tyler<br></div><br></div><br>_______________________________________________<br>Dsg-rich mailing list<br>Dsg-rich@jlab.org<br>https://mailman.jlab.org/mailman/listinfo/dsg-rich<br></div></div></body></html>