View source for Polhe3 meeting 20110713

* progress
** new cell and oven bottom piece
*** Mike should have the first cell sent out to UVa now, need confirmation though.
*** Jie did a summary of [[Convection_Cell#Transitivity_cell_tolerance]]
*** Alan starts to design and make the oven bottom piece to according to the drawing and tolerance, hopefully finish around the time when the new cell arrives before end of July.
** RTD reading
*** the problem: oven RTD is in air and pumping cell (PC) RTD on cell, they are about 5-10cm apart. At room temperature, their reading are very close within 1-2C. at more than 200C, the oven RTD is about 15C higher than PC RTD.
*** Oven RTD is confirmed with 3-wire reading. 
*** the oven RTD's Omega read out unit found to have setting 392 while it should be 385 if the RTD is Omega F3105 model (http://www.omega.com/Temperature/pdf/F3105_3100_W2100_2200.pdf). The error created by the setting is 200C*(0.00392/0.00385)=3.6C and 20C*(0.00392/0.00385)=0.36C, (refer to http://en.wikipedia.org/wiki/Resistance_thermometer#Standard_resistance_thermometer_data). This won't explain the 15C difference.
*** During the transitivity experiment, the reading may have same setting problem. how much it affect results, need to be checked. refer to 
https://hallaweb.jlab.org/wiki/index.php/Oven_Control#Input
** pulse NMR
*** The items we have and a list of items to buy are identified. We have most of stuff for it and we need to buy or make some. refer to [[Polhe3_wanted_item_list_2011_summer]]
** temperature optimization test 
*** redid 210C and 230C spin up.
*** reorganized results
** diffusion mode measurement
*** the current NMR RF coil has 2ohm and about 40cm radius
*** using an existing 4ohm EPR RF coil did some tests. refer to https://hallaweb.jlab.org/wiki/index.php/Diffusion_rate
** convection flow study
*** identify small heater to as the flower driver, need to make sure all material in contact or near the cell is non-magnetic.
** transfer tube wall measurement
*** found ultrasonic gauge

* todo
** new cell and oven bottom piece (zhiwen)
*** follow up 
** RTD reading (Jie)
*** check PC RTD reading setting
*** do calibration once we can take the RTD out 
** pulse NMR (all)
*** order items and refine the list (Zhiwen)
*** find or make coil, capacitor matchbox (Chunhua)
*** write code for reading (Jie)
*** setup (all)
** diffusion mode measurement (Chunhua)
*** make two coils to confine field more.
*** measurement NMR at different RF power, derive optimal H1 to destroy field
*** do another test
** convection flow study (Zhiwen)
*** find out if heater material has magnetic and order them
** temperature optimization test (Chunhua)
*** redo 230 spin down
*** improve analysis and check fitting with error estimation
*** water measurement
** transfer tube wall measurement (Jie)
*** do it

* '''RTD update, solved'''
** '''after talking Jin again, we clarify that the oven RTD is about 10C higher than PC RTD during transitivity experiment when heated to more than 200C and with laser off. The current 15C difference is not unexpected. oven RTD could have used wrong setting during transitivity experiment, but it doesn't affect any result as far as it maintain stable because it's the PC and TC RTD reading counts.'''
** '''we will still do a RTD calibration later anyway.'''

*Calendar
{| class="wikitable" border=1
|-
! Week
! Tasks
! To be done by
! status
|-
| 6/29-7/3
| Complete temperature testing with RTD correction study
| Chunhua, Zhiwen, Jie for RTD
| part
|-
| 
| Tolerance measurement
| Jie, Zhiwen
| done
|-
| 
| ID supply list for pulsed NMR
| Zhiwen
| part
|-
| 7/7-7/13
| Conduct diffusion test
| Chunhua, Zhiwen, (Jie)
| part
|-
| 
| general inventory check and ordering 
| Chunhua, Zhiwen
| part
|-
| 7/14-7/20 (tentative)
| Expect to receive the new cell. Maybe oven fit check (but will not mount for testing), adjustment by Al G. if needed
| Chunhua, Zhiwen
|-
|
| Pulsed NMR prep
| Chunhua, Zhiwen
|-
| 7/20-8/15 (tentative)
| Pulsed NMR setup on a traditional cell
| Chunhua, Jie
|}