SENSEI project S ub- E lectron- N oise S kipperCCD E xperimental I - PowerPoint PPT Presentation

SENSEI project S ub- E lectron- N oise S kipperCCD E xperimental I nstrument Ultra low-energy threshold detectors for light DM Javier Tiffenberg † December 6, 2016 † Fermi National Laboratory 1 3rd Berkeley Workshop on the Direct Detection of Dark Matter December 6, 2016

CCD: readout P 1 P 2 P 3 P 1 P 2 P 3 3x3 pixels CCD state 1 H 3 H 2 channel H 1 2 horizontal register stop H 3 H 2 channel H 1 stop 3 H 3 H 2 .. .. .. H 1 sens node P 1 P 2 P 3 P 1 P 2 P 3 P 1 P 2 P 3 7 ampli fi er capacitance of the system is set by the SN: C=0 . 05pF → 3 µ V/e 2 3rd Berkeley Workshop on the Direct Detection of Dark Matter December 6, 2016

CCD: readout sens H H SW OG VR V node Accumulate the charge in the SW and reset the SN voltage 3 3rd Berkeley Workshop on the Direct Detection of Dark Matter December 6, 2016

CCD: readout sens H H SW OG VR V node Disconnect the SN so it’s floating. Measure the baseline voltage in the SN. 3 3rd Berkeley Workshop on the Direct Detection of Dark Matter December 6, 2016

CCD: readout sens H H SW OG VR V node Move the change to the SN and measure the shift in the voltage 3 3rd Berkeley Workshop on the Direct Detection of Dark Matter December 6, 2016

CCD: readout 4 3rd Berkeley Workshop on the Direct Detection of Dark Matter December 6, 2016

CCD: readout excellent for removing high frequency noise but sensitive to low frequencies 4 3rd Berkeley Workshop on the Direct Detection of Dark Matter December 6, 2016

Readout noise: empty pixels distribution 4 10 σ = 1.8 e 3 10 2 10 10 1 -30 -20 -10 0 10 20 30 pixel value /e 5 3rd Berkeley Workshop on the Direct Detection of Dark Matter December 6, 2016

Lowering the noise: Skipper CCD Main difference: the Skipper CCD allows multiple sampling of the same pixel without corrupting the charge packet. The final pixel value is the average of the samples Pixel value = 1 N Σ N i (pixel sample) i 6 3rd Berkeley Workshop on the Direct Detection of Dark Matter December 6, 2016

Lowering the noise: Skipper CCD Main difference: the Skipper CCD allows multiple sampling of the same pixel without corrupting the charge packet. The final pixel value is the average of the samples Pixel value = 1 N Σ N i (pixel sample) i Regular CCD Skipper CCD signal pixel charge pedestal measurement high frequency noise low frequency noise 6 3rd Berkeley Workshop on the Direct Detection of Dark Matter December 6, 2016

This instrument already exist: SENSEI 7 3rd Berkeley Workshop on the Direct Detection of Dark Matter December 6, 2016

Image taken with SENSEI m] 250 µ y [pix=15 2000 240 1500 230 220 1000 210 500 200 0 50 60 70 80 90 100 110 120 µ x [pix=15 m] 8 3rd Berkeley Workshop on the Direct Detection of Dark Matter December 6, 2016

Charge in pixel distribution. Counting electrons: 0, 1, 2.. 9 3rd Berkeley Workshop on the Direct Detection of Dark Matter December 6, 2016

Charge in pixel distribution. Counting electrons: 0, 1, 2.. 9 3rd Berkeley Workshop on the Direct Detection of Dark Matter December 6, 2016

Counting electrons: ..38, 39, 40.. 10 3rd Berkeley Workshop on the Direct Detection of Dark Matter December 6, 2016

Counting electrons: ..38, 39, 40.. 10 3rd Berkeley Workshop on the Direct Detection of Dark Matter December 6, 2016

55 Fe X-ray source 11 3rd Berkeley Workshop on the Direct Detection of Dark Matter December 6, 2016

55 Fe X-ray source 11 3rd Berkeley Workshop on the Direct Detection of Dark Matter December 6, 2016

keep counting: ..1575, 1576, 1577.. 12 3rd Berkeley Workshop on the Direct Detection of Dark Matter December 6, 2016

√ Noise vs. #samples - 1/ N 13 3rd Berkeley Workshop on the Direct Detection of Dark Matter December 6, 2016

Skipper CCD: Operation mode Counting electrons ⇒ noise has zero impact It can take about 1h to readout a 4kx4k sensor Dark Current is the limiting factor It’s better to readout continuously to minimize the impact of the DC Number of DC events (100 g y) DC = 1 × 10 − 3 e pix − 1 day − 1 DC = 10 − 7 e pix − 1 day − 1 Thr /e 1 × 10 8 1 × 10 4 1 2 × 10 4 2 × 10 − 5 2 3 × 10 − 2 3 × 10 − 14 3 Measured upper limit for the DC in CCDs is 1 × 10 − 3 e pix − 1 day − 1 . Could be orders of magnitude lower. Theoretical prediction is O ( 10 − 7 ) . 14 3rd Berkeley Workshop on the Direct Detection of Dark Matter December 6, 2016

Skipper CCD - electron recoil reach Electron recoil sensitivity computed by LDRD collaborators: Rouven Essig, Jeremy Mardon, Tomer Volansky, Tien-Tien Yu. 15 3rd Berkeley Workshop on the Direct Detection of Dark Matter December 6, 2016

From yesterday’s Agency-Perspective talks SENSEI is the ultimate silicon ionization detector Dream sensor for electron recoil channel 16 3rd Berkeley Workshop on the Direct Detection of Dark Matter December 6, 2016

SENSEI and Skipper-CCD detectors prospects SENSEI is the ultimate silicon ionization detector Unmatched performance for electron recoil channels Probe DM masses at the MeV scale through electron recoil. Probe axion and hidden-photon DM with masses down to 1 eV. Probe DM masses as low as 0.1 GeV through nuclear recoil. Push boundaries of coherent ν -nucleus interaction experiments. Participants Fermilab: Javier Tiffenberg, Yann Tel Aviv University: Tomer Volansky Guardincerri, Miguel Sofo Haro CERN: Tien-Tien Yu LBNL: Steve Holland, Christopher Bebek Stanford University*: Jeremy Mardon Stony Brook: Rouven Essig 17 3rd Berkeley Workshop on the Direct Detection of Dark Matter December 6, 2016

BACK UP SLIDES 18 3rd Berkeley Workshop on the Direct Detection of Dark Matter December 6, 2016

CCD: readout - typical operation for DM searches Clean the CCD { We take long exposures to Wait 30000s (~8.3 hs) minimize the number of readouts. The exposure is eventually Read - exposure with hits limited by the dark current. The blank images provide an Read - blank (0s exposure) excelent measurement of the background produced by readout The number of real events (produced by particles) scales with the total exposure time. The number of fake events (product of readout noise) scale with the number of readings (images taken). It is better to read as few times as possible. 19 3rd Berkeley Workshop on the Direct Detection of Dark Matter December 6, 2016

Electron density-of-states (1509.1598) 20 3rd Berkeley Workshop on the Direct Detection of Dark Matter December 6, 2016

Whats next: Installation @MINOS & low radiation package 21 3rd Berkeley Workshop on the Direct Detection of Dark Matter December 6, 2016