The second part of this thesis focuses on the characterization of the Multiwavelength Submillimeter Inductance Camera (MUSIC), a photometric imaging camera that was commissioned at the Caltech Submillimeter Observatory (CSO) in 2012. This work studies the performance of the detectors in the context of a model such physical.
Introduction
A non-thermal component will lower the resulting estimates of total mass by tens of thousands of percent [14, 7]. In this chapter, we fit parametric models to the combined multiwavelength data set for a subset of the CLASH clusters.
Model
We assume that the total pressure is the sum of the thermal pressure and the nonthermal pressure due to internal gas motions. The change in the temperature of the CMB measured at a frequencyνand projected radiusRis given by.
Description of the Multiwavelength Dataset
Chandra X-ray
Bolocam Thermal SZ Effect
The assumption that the off-diagonal elements are zero is a good but not perfect description of the data. The input to the multiwavelength analysis is the µKCMB imageTSZin units, the CTSZ diagonal covariance matrix, and the transfer function of the data processing pipeline.
HST and Subaru Gravitational Lensing
The inner boundary is determined by the resolution of the highest degree of refinement of the adaptive mesh. 44] is to focus the convergence profile on the peak of the X-ray emission rather than on the peak of the convergence map.
Method
Joint Analysis of Cluster Observations (JACO)
After that, it is rebinned and changed to an identical grid to that of the data. We allow the nuisance parameters to vary over physically reasonable limits and then marginalize to obtain constraints on the parameters of interest.
Sample Definition
Model Determination
The data do not guarantee the full complexity of the model presented in Section 1.2 for any cluster in the spherical sample. We find that only two groups prefer the non-thermal pressure component; Abell 0383 prefers model 1a and MACS J prefers model 1b.
Results
- Abell 383
- Abell 611
- MACS J0429.6-0253
- MACS J1311.0-0310 and MACS J1423.8+2404
- MACS J1532.8+3021
Both non-thermal pressure support and an extension of the array along the viewing direction will raise the detected lens mass compared to the X-ray/SZ detected mass. We use the other five clusters to place an upper bound on the nonthermal pressure support.
Discussion
We selected clusters that are circular in the plane of the sky, as evidenced by X-ray and NW data. Only compressing the galaxy cluster along the line of sight would lead to an underestimation of the non-thermal pressure support needed to explain the discrepancy between our results and the hydrodynamical simulations.
Summary
We recall that the SZ effect results in a decrease in temperature and the positive excursion at intermediate radii is due to the filtering applied during data processing. The bottom panel is the convergence profile reconstructed by the SaWLens algorithm from the strong and weak lensing constraints, converted to a surface mass density profileΣ=κΣcrit.
Notation
This should be read as the power spectral density of the fluctuations δx originally caused by the "source". Finally, we denote the one-sided cross-spectral power density (CPSD) between the real quantities x(t) and y(t) as Sx,y(ν).
Responsivity
Antenna Theory
Popt=ηoptkB(Tload+Texc)∆νmm, (2.7) whereηoptis the total optical efficiency of the system (taking into account all sources of loss between the cryostat window and the detector), Tload is the temperature of the beam-filling, black- body load, Texc is the excess load due to current reaching the detector from the inside of the cryostat, referred to the cryostat window, and ∆νmm is the effective bandwidth of the detector. The remaining beam reaches the sky where the effective load due to atmospheric emission depends on the temperature of the atmosphere, the optical depth at zenithτ, and the air mass 1/sine (assuming a plane-parallel atmosphere) where the height (height ) is.
Generation-Recombination Equation
Solving this equation leads to an exponential decay in the total number of quasi-particles with time. In the constraint that the optical generation of quasi-particles dominates over thermal generation and that the recombination of quasi-particles dominates.
Mattis-Bardeen Theory
The important result here is that the complex conductivity is a linear function of the quasiparticle density. This is due to the suppression of the quasiparticle density by the factor exp(−∆0/kBT)≈ exp(−1.76Tc/T).
Complex Conductivity and Surface Impedance
We would like to relate these measurable properties to the quasiparticle density of a thin superconducting film. The frequency and quality factor of the resonant circuit are given by the well-known equation fres= 1.
Resonant Circuit
An example of the single sample output is shown in the right column. This can easily be converted into changes in the amplitude of the carrier tone using equation (2.61).
Nonlinear Kinetic Inductance
We see that as the carrier power increases, the quasi-particle response normal to the resonance curve remains fixed, while the quasi-particle response tangential to the resonance curve drops. As the carrier power increases beyond this point, the quasiparticle direction rotates beyond the normal direction of the resonance curve.
Impedance Mismatch
This results in a decrease in the overall magnitude of the response and a clockwise rotation of the quasi-particle direction. Equation (2.100) allows for a rotation of the resonant circle with respect to the transmission-off resonance, as observed.
Nonantenna Response
Equation (2.7)) will now be the sum of the power coupled through the antenna and the power absorbed directly, or. The efficiency is expected to scale with the aluminum cross-sectional area opt,dir∝A.
Substrate Heating and Nonequilibrium Dynamics
The power that the substrate must absorb to maintain the elevated temperature is given by the thermal conductivity function of the shape. This equation can be solved to obtain an expression for the substrate temperature.
Nonuniform Absorption
The average density of quasiparticles along the length of the section Al is then the quantity that determines the response of the resonator. We would like to derive an expression for the mean response to the section length Al, since this is the quantity we are actually measuring.
Response to Unresolved Astronomical Source
The response is easily measured by scanning the telescope across a bright unresolved source of known flux density and examining the peak height in the quadrature sum of the I and Q time currents. If the response due to direct absorption is small compared to the antenna response, then the ratio of the peak height to the flux density is a good measure forrsrc.
Noise
Electronics Noise
- Additive
- Multiplicative
We first consider the input side of the readout electronics, which we define as everything between the DAC and the HEMT. The fifth column is the accumulated sound temperature, related to the input of the HEMT.
Detector Noise
- Fundamental
- Two-Level Systems
- Atmospheric
It can be shown (e.g., that this causes the power spectral density of sky light temperature fluctuations that it gives. We are primarily interested in how atmospheric noise will manifest itself in the time courses of MUSIC detectors.
Summary
Increasing α or ˜κ2 improves the frequency response of the resonator to changes in quasiparticle density, which directly translates into a reduction in the TLS NEP. In the previous chapter we presented a theoretical framework that describes the behavior of the MUSIC detectors.
Responsivity
- IQ Sweeps
- Dark Temperature Sweeps
- Hot/Cold
- Single-Spin Density of Electron States at the Fermi Energy Level
- Recombination Coefficient
- Nonuniform Absorption
- FTS
- Skydips
As mentioned in Section 3.2.2, there is disagreement in the normalization of the dark frequency and scattering trajectories. The best-fitting parameter values are marked in the upper left corner of the lower panel.
Noise
Additive Electronics
Again, we use an MCMC to fit the data, including the heat/cold results as before. The results are then included as a preliminary analysis of the cloud dip data for the antenna-coupled resonators.
Multiplicative Electronics
We also note that in all cases the noise in the amplitude direction is comparable in size to the noise in the phase direction. In general, however, we do not observe the expected scaling of HEMT noise magnitude with sensitivity.
Fundamental
Indeed, in the phase direction, room temperature electronic noise appears to be comparable, as evidenced by the reduced correlation between non-resonant carriers on separate readout plates. All reasonable considerations indicate that the floor due to fundamental noise should be greater than the white noise floor of the electronics in the frequency direction, so measuring this white noise floor would allow the model to be validated.
Two-Level Systems
The solid black lines indicate the best fit of the excess noise in the frequency direction to the Pint−1/2 scaling characteristic of TLS noise. This figure indicates a steepening of the TLS noise spectrum from the ν−1/2 behavior assumed by the model.
Atmospheric
The position of the detector arrays in the focal plane unit (FPU) has not changed since 20 September 2012. As an example, A2L and A2U refer to the lower and upper bands of the detector array in row A, column 2.
Science-grade Arrays
- Power Dependence
We show the magnitude of near-resonance transmission as a function of power for one of the test devices in Figure 4.2. The purple dashed line indicates the expectation of the TLS-induced loss in the low power limit, based on analysis of the frequency shift data.
FTS
We find that for these two detector arrays the ratio of the measured to the designed band center is band dependent. The rest of this thesis will focus on the calibration of the detectors on the A2 and B2 arrays.
Yield
Simulations of the bandpass filter, also shown in Figures 4.5-4.6, show no edges. The small-scale features are measured accurately. Bottom: A zoom-in on the network analyzer of the B2 detector array.
Dark Temperature Sweeps
Then, from left to right, the columns show the number of resonators left after placing additional quality cuts. The bottom two rows are in units of percentage of resonators over the designed number.
Hot/Cold
The quoted values are the (median)±(median absolute deviation), calculated using all detectors of the specified band. Lyot Account for the loss due to the cutting of the beam at the Lyot stop.
Skydips
The black dashed line indicates the expected spillover fraction due to the expected inefficiency of the MUSIC optics. The black dashed line indicates the expected spillover fraction based on the expected inefficiency of the MUSIC optics (see text).
Loading
Responsivity
Atmospheric transmission at the zenith is calculated using the ATM model with mm of precipitable water vapor determined from the machine measurement of τ225 at the time of observation. Since all calibration measurements are collected at low read power, this effect is not included in our model and therefore not included in the predicted response.
Optics Reconfiguration
- Dark Temperature Sweeps
- Hot/Cold
- Skydips
- Sleeve Test
- Loading
- Responsivity
- Secondary Collar Test
- Large-Angle Beammaps
The reconfiguration of the optics actually resulted in a significant increase in the optical efficiency of the detectors. Note that this only applies to detectors located near the center of the focal plane.
Conclusions
We find that there are indeed significant side beams and a diffuse wide-angle response outside the main beam. This explains more than half of the observed discrepancy between our measured and predicted response to the unresolved astronomical source.
Electronics Noise Removal
Likewise, the quantity δ φ is a linear combination of the phase fluctuations of the individual electronic components. We start by using the sample mean of the data to estimate the amplitude and phase of the carriers.
On-Resonance Noise Removal
Residual Noise
Comparison to Calibrated Model Predictions
