Craig Cahillane

Sixth Year Physics Grad Student at Caltech Logo
Work in Experimental Gravity forLIGO Logo
Curriculum Vitae on gitlab

I am currently a graduate student at Caltech, started August 2014.
Worked as a commissioner of the Advanced LIGO Hanford Gravitational-Wave Observatory intermittently for a total of two years.
Focused on modeling laser frequency and intensity control systems' noise masking the gravitational-wave signal.
Measured and simulated interferometer transfer functions to infer interferometric parameters, including the resonant arm power.
Measured and simulated the differential arm (DARM) degree of freedom for comparison between the expected response to gravitational-waves and reality.
Created the advanced-detector era interferometric calibration uncertainty budget pipeline.

Python, C/C++, MATLAB, Unix, Javascript, Git, LaTeX
Interferometer simulation Finesse
Linear Simulation and Optimization of analog electronic circuits LISO

nds2utils: convenient user interface for the python nds2 LIGO data-acquisition client. (gitlab)
beamtrace: python3 based gaussian laser beam ABCD matrix propagator. (gitlab)

Markov Chain Monte Carlo (MCMC): emcee
Gaussian Process Regression (GPR): scikit-learn

Worked in the Caltech optical coatings thermal noise lab for testing aluminum gallium arsinide (AlGaAs) optics coatings.
Locked two lasers' frequencies to two Fabry-Perot cavity lengths with the goal of measuring cavity mirror coatings Brownian noise.
Mode matching, polarization, mode cleaning, laser intensity control, laser frequency control, cavity temperature control

Spectrum Analyzers: SR785, Agilent A4395A, HP8560E
Oscilloscopes: Tektronics 3032 and 3034
RF Generator: Marconi 2023A
Preamplifiers: SR560
GPIB: Developed python scripts to acquire data, monitor, and control lab electronics in real time.
Soldering, Circuit design and noise analysis, Control systems, Optics

Passed Caltech Machine Shop Course ME113
Trained on the Lathe, Mill, Bandsaw, Drillpress, Laser Printer, 3D Printer, and Waterjet.

2015-2017 LIGO Caltech Outreach Lead.
Organized ~15 trips to local elementary and high schools, and even more talks to schools out of state, including Notre Dame.
Black Hole Merger Demonstration. Simulates gravitational wave emission from black hole binaries near the end of their lives.
Interactive Fabry-Perot optical cavity. Visualizes how lasers and mirrors interact in a simple two-mirror resonator.
Interactive LHO correlated noise plot. Demo of my interactive LIGO Hanford correlated noise plot.

Notre Dame Logo University of Notre Dame. Graduated 2014. Degrees in Physics and Computer Science. 3.795 GPA

Lasers, Optics, Control Systems, Cosmoslogy, Astrophysics, Arduino, Raspberry Pi, Golf, Tennis, Frisbee, Notre Dame Football, 538 The Riddler


First Author:
Calibration Uncertainty for Advanced LIGO's First and Second Observing Runs (arXiv)

Contributing Author:
Calibration of the Advanced LIGO detectors for the discovery of the binary black-hole merger GW150914 (arXiv)
Systematic calibration error requirements for gravitational-wave detectors via the Cramér-Rao bound (arXiv)

In Prep (as first author or member of paper-writing team):
Sensitivity and Performance of the Advanced LIGO Detectors in the Third Observing Run
Frequency Noise for Third-Generation Gravitational Wave Detectors

Full Collaboration Papers:
GW170817: Observation of Gravitational Waves from a Binary Neutron Star Inspiral First direct detection of gravitational waves from a neutron star binary.
Observation of Gravitational Waves from a Binary Black Hole Merger First detection of gravitational waves.


Shot Noise Calculator
Latest Coatings Thermal Noise Budget in my lab at Caltech
Interactive Fabry-Perot Optical Cavity Animation in Javascript
Blood Alcohol Content Estimator in React
My animated solution to a 538 The Riddler problem - May 12, 2017
Wikipedia contributions
Sum of Exponential and Laplace random variables

Interactive Plot Gallery:

LIGO Hanford Noisebudget Interactive SVG
SVG plot of Arm Power Measurements
Interactive Frequency Noise Budget
Frequency noise to DARM coupling
Finesse vs Ward vs actual LHO DARM measurement

LHO correlated noise spectra

LHO Correlated Noise Budget - comparisons of many numbers of averages
LHO Correlated Noise Budget - 1000 averages - ungated vs gated mean ASD vs median averaged ASD
LHO Correlated Noise Budget - 20000 averages - ungated vs gated mean ASD vs median averaged ASD
Raw DCPD CSDs plus SUM plus NULL - 1000 averages
LHO DCPD PSDs - 1000 averages
LHO CSDs and coherence - 20000 averages
LHO Correlated Noise Budget - Comparison with different DARM OLGs - gated- and median-averaging
LHO Correalted Noise Budget - Comparison between shot noise balanced and unbalanced PDs

Created by Craig Cahillane
Last Updated: