Demet
Kırmızıbayrak

Hi and welcome to my personal website! I'm a postdoctoral scholar and research associate in the High Energy Astrophysics Group at Caltech.

I study black holes and neutron stars, the most extreme objects in the universe, by developing novel techniques, using X-ray timing, spectroscopy, polarimetry, astrostatistics and modelling.

Explore My Research Get in Touch

About Me

Demet Kırmızıbayrak at Caltech Cahill Centre

In the broad sense, I summarize my research interests with this question: “What new knowledge of physics and the universe can we unveil by studying phenomena in the sky?” I am especially passionate about improving our understanding of physics by probing the mysterious processes, geometries, and transient behaviour of compact objects, as well as developing novel tools to study the diverse mysteries of our universe.

Before Caltech, I completed my PhD at the University of British Columbia (2018–2025) and my MSc at Sabancı University in Istanbul. I also hold a double BSc in Physics and Industrial Engineering from Koç University.

View my CV

When I'm not chasing compact objects…

You'll find me doing yoga, dancing bachata, playing volleyball (co-founder of the legendary SJC Honeybadgers at UBC, yes, we were formidable), or attempting to learn a new language (ah oui! 1200+ day streak on Duolingo and counting!). My curiosity stretches well beyond astrophysics, from the arts and science communication to the creative possibilities of artistic and scientific data visualization.

Research

My work explores the most energetic and exotic corners of the universe, using multi-wavelength observations, novel data analysis techniques and theoretical modelling.

Astrostatistics & Data Science

My statistical methods for high-energy astrophysics span Bayesian, frequentist and entropy-based techniques, such as Wiener deconvolution and mutual information. This includes building large-scale data processing pipelines for X-ray data.

Wiener Deconvolution Mutual Information

Black Holes & Accretion

I develop and adapt novel timing methodologies to study time lags and reverberation mapping in accreting black holes, probing the geometry of accretion disks and relativistic jets.

Timing Analysis Variability QPOs Jets

Magnetars

Magnetars are neutron stars with the most powerful magnetic fields in the universe! I study them through theoretical modelling, time-resolved spectroscopy, and X-ray polarimetry. Here is a public database of over 1,500 magnetar bursts that I led broadband spectral analysis for.

X-ray Polarimetry Spectroscopy IXPE Modelling

Instrumentation & Future Missions

I actively contribute to the science cases and simulations for next-generation X-ray observatories, including AXIS and the Colibri telescope concept, and serve on the IXPE and NuSTAR Science Teams.

AXIS Colibri NuSTAR

Multi-wavelength Astronomy

I combine X-ray data with optical and radio observations to build comprehensive pictures of compact objects, from transient outbursts to steady-state accretion.

Multi-wavelength Transients X-ray Binaries

Neutron Stars & Pulsars

I use X-ray polarization to probe the geometry and physics of neutron stars. This includes studying the complex rotational dynamics and polarization properties across various bands.

IXPE Spectro-polarimetry

Selected Publications

First-author and selected co-author works. For a complete list, see my NASA ADS, ResearchGate, or Google Scholar profile.

2024
Nature Astronomy

Complex rotational dynamics of the neutron star in Hercules X-1 revealed by X-ray polarization

Heyl, J., ..., Kırmızıbayrak, D., ... et al.

Nature Astronomy, 8, 1047–1053

DOI →
2022
Science

Polarized X-rays from a magnetar

Taverna, R., ..., Kırmızıbayrak, D., ... et al.

Science, 378 (6620): 646–651

DOI →
2025
Astronomy & Astrophysics

Crab pulsar: IXPE observations reveal unified polarization properties in the optical and soft X-ray bands

González-Caniulef, D., ..., Kırmızıbayrak, D., ... et al.

Astronomy & Astrophysics, 693, A152

DOI →
2023
Proc. IAU

Probing magnetars using spectral lines with future telescopes

Kırmızıbayrak, D. & Heyl, J.

Proceedings of the IAU Symposium No. 363: Neutron Star Astrophysics at the Crossroads

DOI →
2024
MNRAS

The detection of polarized X-ray emission from the magnetar 1E 2259+586

Heyl, J., ..., Kırmızıbayrak, D., ... et al.

Monthly Notices of the Royal Astronomical Society, 527(4), 12219–12231

DOI →
2026
Conference Talk

Compact Objects through Novel Timing Methodologies

Kırmızıbayrak, D.

AAS HEAD Session · American Astronomical Society Meeting, Pasadena, CA

2025
arXiv

The Advanced X-ray Imaging Satellite Community Science Book

Koss, M., ..., Kırmızıbayrak, D., ... et al.

arXiv: 2511.00253

arXiv →
2017
ApJ Supplement Series

Broadband spectral investigations of magnetar bursts

Kırmızıbayrak, D. et al.

The Astrophysical Journal Supplement Series, 232(1)

DOI → Database →

PhD Dissertation

"New tricks for old stars: studying compact objects through novel methodologies in timing, energy and imaging"
University of British Columbia, 2025  ·  Read it here →

Academic Service

Here's a (probably non-comprehensive) list of my efforts for the scientific community through mission science teams and peer review.

Science Teams

  • 2025–PresentMember, Caltech NuSTAR Science Team
  • 2022–PresentMember, IXPE Science Team
  • 2022–2026Member, AXIS Compact Objects & Supernova Remnants Science Working Group
  • 2018–PresentMember, Colibrí X-ray Telescope Science Working Group

Peer Review & Panels

  • 2026Reviewer Panelist, NuSTAR 12th General Observing Cycle
  • 2025Reviewer Panelist, NASA IXPE 3rd General Observing Cycle
  • 2026Proposal Reviewer, Caltech SURF Program

Conference & Community

  • 2026Session Chair, AAS HEAD Meeting, Pasadena, CA
  • 2026Chambliss Poster Judge, AAS HEAD Meeting, Pasadena, CA
  • 2022–2025Member, Canadian Space Agency Space Astronomy Topical Team: High Energy Astrophysics & Gravitational Waves

Science Communication & Media

I'm passionate about science communication and public outreach. Here's some of my past work in this space. Feel free to reach out with outreach ideas!

NuSTAR

NuSTAR Observes a Transient Magnetar

A news piece I wrote for the NuSTAR team on the mission's observations of the transient magnetar 1E 1547.0-5408, probing its connection to Fast Radio Bursts.

Read →
Astrobites

The Field That Rends the Light

An Astrobites article I helped shape, featuring my visualization from the 1E 2259+586 IXPE paper.

Read →
UBC Physics

IXPE Solves 50-Year-Old Mystery of Wobbling Neutron Star

Our Nature Astronomy paper on Her X-1's complex rotational dynamics, as covered by UBC.

Read →
Sci News

IXPE: X-ray Polarization from a Magnetar Outburst

Science news coverage of the first magnetar X-ray polarization measurement.

Read →
UBC Global

Building Community During the Pandemic

On my work as Residence Community Coordinator at St. John's College during COVID-19.

Read →
Public Talks
YouTube

Scientific & Artistic Visualization

I'm deeply interested in the intersection of science and art through data visualization for astrophysics. My channel features visualizations of black holes, neutron stars, and more.

Watch →

Get in Touch

Whether you're interested in collaborations, science outreach, or just want to talk about some data or how beautifully weird compact objects are, my inbox is open.

✉
Email
demet@caltech.edu
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ResearchGate
Demet-Kırmızıbayrak

Cahill Center for Astronomy & Astrophysics
California Institute of Technology
Pasadena, CA, USA