Run 2

1. Upgrades from last run: added a calibrated RuOx thermometer on the detector housing and a thermal link between the 600mK floor and still.
2. Detector housing base T: ~25mK. This is from extrapolation. The calibration lower limit is 43.8mK.
3. Tc's measured are consistent with CWRU's
4. Ic vs T are consistent with that of CWRU
5. Fixed a few issues of the DAQ software (with Jeter)
6. Installed cdmsbat and analyzed background data (with help from Lauren, Bruno, and Jeter). Results shown below.
   • Flash 3min and take data 3min
   • Flash 3min and take data 15min
   • Flash 3min and take data 30min
   • Flash 3min and take data 60min
   • Flash 12sec and take data 5min
   • Flash 12sec and take data 60min

A thermal link between the 600mK tower floor and the fridge still is added. We also mounted a calibrated RuOx thermometer from Lakeshore on the detector housing.

The base temperature of the thermometer on the detector housing is around 25mK this time. In the last run, the base temperature of the thermometer on the mixing chamber was about 38mK. The base temperature is also relatively stable.

Original Post

Send 1mVpp 100Hz triangle signal, apply different power to the mixing chamber, and watch at which resistance (temperature) the triangle wave disappear or reappear. The resistances were read when the temperatures were changing fast, there were some lag effect.

Numbers from CWRU

• G9 after Implantation (Run 14 results)
• SQUET # 8, Sidecoax ZB5-1, Stripline #25, ZIP Board #5, RTF Board #1.7

We obtained consistent Tc values with that from CWRU at June 5, 2001.

Original post

Ic vs T plot of the above table

Plots and more details

The noise spectrum from the DAQ software and the analysis package cdmsbat are plotted. Note that the psd from the cdmsbat are normalized to roughly match that from the DAQ software.

1. DCRC v1 is used. Trigger thresh hold can not be adjusted with the resolution as needed.
2. Charge: ADS1602, 2.5MHz 16-bit digitizer
3. Phonon: ADS1601, 1.25MHz 16-bit digitizer
4. Charge gain after Vf: 10.

1. The glitches on the pulses caused by the lookback time are removed.
2. Trace length 1.6ms, lookback time 400us
3. Charge trace length 3998, pre-pulse 998, post pulse 3000.
4. Phonon trace length 1998, pre-pulse 498, post pulse 1500.
5. Flashing during data taking feature is added to the vi.

1. Stop the run after a given amount time/number of events.
2. Save hardware settings in a file to be used in data processing

cdmsbat is installed and configured to run successfully with the help of Bruno, Lauren, and Jeter. Some information can be found here

The last two digits '01' number the sub run in the main run. The name 'f3md3m' means flashing 3 min and them taking data for 3 min. Run201 analysis is in this page. Others can be found in the links below.

Used the same calibration parameters as f3md3m. f3md60m plots

We didn't have chance to take data with a radioactive source in this run. Instead the energy scale is determined by figuring out all the gains in the data acquisition and processing chain. The amplitude of the charge pulse Vf on the feedback capacitor Cf is Vf = Q/Cf. The gain from Vf to the digitizer is 10 (from Jeter). The resolution of the digitizer ADS1602 is V_REF(3V)/(2¹⁵-1) = 9.16×10^-5V. The data recorded in the raw files is in units of digitizer bins. The corresponding RQs to the charge pulse amplitudes are QIOFvolts and QOOFvolts. The conversion factor from the pulse height to the RQ is calculated by a fit to the data in the following table.

Fit of QIOFvolts vs pulse height

So we have the relationships:

• Vf = Q/Cf
• Vf*g = Ad*R; g=10, Ad is the pulse height, and R=9.16×10^-5V
• Ad*b = QIOFvolts
• Er = N*ε = ε*Q/e; ε = 3eV and e=1.6×10^-19C

From above we get

• Er = Cf*R/(g*b*e)*ε*QIOFvolts = 198.56*QIOFvolts (eV) = qa**QIOFvolts (eV)

Using a method similar to the standard one to to the crosstalk correction. The transformation is

• Qi = a*QIOFvolts + b*QOOFvolts
• Qo = c*QIOFvolts + d*QOOFvolts

By charge conservation we have

• Qi + Qo = a*QIOFvolts + b*QOOFvolts + c*QIOFvolts + d*QOOFvolts = QIOFvolts + QOOFvolts ⇒
  • a + c = 1
  • b + d = 1

To fully determine the transformation matrix, we need to know the slopes of the QIOFvolts and QOOFvolts bands in the (QIOFvolts, QIOFvolts) plot. The slopes can be obtained by fits to the bands directly. But the QOOFvolts band doesn't have so many events to define it clearly. We use a different technique to determine it. In the zeroth order, define

• Qpart = (QIOFvolts - QOOFvlots)/(QIOFvolts + QOOFvlots).

On the (QOOFvolts, QIOFvolts) plot, the QIOFvolts and QOOFvolts bands are represented by two straight lines QOOFvolts = ki * QIOFvolts and QOOFvolts = ko * QIOFvolts respectively. On the Qpart histogram, the two bands are two peaks at

• Qipart = (1 - ki)/(1 + ki)
• Qopart = (1 - ko)/(1 + ko)

The slope ko can be determined from the value of Qopart. ki, however, is very small, and Qipart is very close to 1. This method can not be used. We have to fit the QIOFvolts band to get ki.

Once we get ki and ko, redefine the charge partition as

• Qpart = (Qi - Qo)/(Qi + Qo)

Since Qi and Qo are orthogonal, we know Qpart = 1 for Qi band and Qpart = -1 for Qo band

• (a + b*ki - c - d*ki)/(a + b*ki + c + d*ki) = 1 ⇒
  • c + d*ki = 0
• (a + b*ko - c - d*ko)/(a + b*ko + c + d*ko) = -1 ⇒
  • a + b*ko = 0

Now the transformation can be completely determined.

After energy correction

• Qi = qa * QIOFvolts
• Qo = qa * QOOFvolts

The following cuts are used in the plots

Plots after energy and crosstalk corrections

Cut: No cut

Cut: No cut

Cut: Pt > 5 & inrange(Xdel, -50, 50) & inrange(Ydel, -50, 50)

Cut: 0.93 < Qpart & Qpart < 1.07 & 5 < Qsum & Qsum < 200

There is no spectral line I can use to do the position correction. I just plot the events before the correction.

Cut: Pt>5 & inrange(Xdel, -50, 50) & inrange(Ydel, -50, 50) & cQchi2

Cut: Pt>5 & inrange(Xdel, -50, 50) & inrange(Ydel, -50, 50) & cQchi2

Make the following transformation:

• Pa = r(1) * PAOFev
• Pb = r(2) * PBOFev
• Pc = r(3) * PCOFev
• Pd = r(4) * PDOFev

Phonon energies are adjusted to let the four channels have the same distribution. The normalization is chosen to be

• r(1) + r(2) + r(2) + r(4) = 4

For Run 'f3md3m', the parameters are

• r = [1.2706 1.0191 1.0751 0.6353]

The phonon energy distribution after adjustment is

Cut: No cut

The over all calibration minimizes the χ² between the phonon energy Pt and the charge energy Qsum in the energy range 5 < Qsum < 100keV. This gives an overall factor of 2.6853e-08.

Cut: 5 < Qsum & Qsum < 100 & cQchi2 & cQin

The yield Y = Qsum/Pt is plotted versus the time after flashing to see the neutralization change as time goes on.

Cut: cQin & cQchi2 & 5<Qsum & Qsum<100