Postdoc for

PhD in Experimental Gravity from

craigcahillane@fastmail.com

Curriculum Vitae on gitlab

I am currently a postdoc at LIGO Hanford Observatory, starting in February 2021.

I graduated from Caltech with a PhD in experimental astrophysics, with a focus on calibration
uncertainty and interferometer controls.

As a grad student I worked as a commissioner at LIGO intermittently for a total of two years.

I focused on modeling laser frequency and intensity control systems' noise masking the
gravitational-wave signal,

measured and simulated interferometer transfer functions to infer 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,

and 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.

Black Hole Merger Demonstration

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.

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 CramÃ©r-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.

Interactive Fabry-Perot Optical Cavity Animation in Javascript

Interactive PyQt5 widget for fast analysis of LIGO measured transfer functions

Shot Noise Calculator

Latest Coatings Thermal Noise Budget in my lab at Caltech

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

SVG plot of Arm Power Measurements

Analog OUT2 vs REFL SERVO ERR SVG

Interactive Frequency Noise Budget

Frequency noise to DARM coupling

Finesse vs Ward vs actual LHO DARM measurement

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 Correlated Noise Budget - Comparison between shot noise balanced and unbalanced PDs

High power OMC scan with increased 9 MHz modulation depth

Created by Craig Cahillane

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