contact info
- Address: NRAO, P.O. Box O, Socorro, NM, 87801
- Office: SOC 206
- Phone: 575 835 7248
- Email: pdemores at nrao
research
My main research focus is on observations of radio pulsars, especially the areas of data analysis and instrumentation. High-precision timing of millisecond pulsars gives us a unique "laboratory" for fundamental physics and astrophysics, including tests of general relativity and potential use as a very low frequency (nHz) gravitational wave detector. I am involved in designing and building specialized instrumentation for pulsar observations, with the goal of obtaining the best possible timing precision. I am also exploring new methods for characterizing and compensating for the effect of the interstellar medium (ISM) on the pulsar signals. In addition to improving timing results, this research provides a unique view on the structure of the ionized ISM present in our galaxy.
- Curriculum vitae (pdf)
recent publications
- The Angular Broadening of the Galactic Center Pulsar SGR J1745-29: A New Constraint on the Scattering Medium, Bower et al., ApJL accepted (2013). (ADS, arxiv)
- Cyclic spectroscopy of The Millisecond Pulsar, B1937+21, Walker et al., ApJ accepted (2013). (ADS, arxiv)
- A strong magnetic field around the supermassive black hole at the centre of the Galaxy, Eatough et al., Nature, 501, 7467 (2013). (ADS, arxiv)
- Limits on the Stochastic Gravitational Wave Background from the North American Nanohertz Observatory for Gravitational Waves, Demorest et al., ApJ 762, 94 (2013). (ADS, arxiv)
- Constraining the Vela Pulsar's Radio Emission Region Using Nyquist-limited Scintillation Statistics, Johnson et al., ApJ 758, 8 (2012). (ADS, arxiv)
- Cyclic Spectral Analysis of Radio Pulsars, Demorest, MNRAS 416, 2821 (2011). (ADS, arxiv)
- A Quantitative Model for Drifting Subpulses in PSR B0809+74, Rosen and Demorest, ApJ 728, 156 (2011). (ADS, arxiv)
- The Massive Pulsar PSR J1614-2230: Linking Quantum Chromodynamics, Gamma-ray Bursts, and Gravitational Wave Astronomy, Ozel et al, ApJ 724, L199 (2010). (ADS, arxiv)
- A two-solar-mass neutron star measured using Shapiro delay, Demorest et al, Nature 467, 1081 (2010). (ADS, arxiv)
current projects
- NANOGrav - the North American Nanohertz Observatory for Gravitational Waves. US/Canadian research collaboration working to detect nHz-frequency gravitational radiation using a pulsar timing array.
- IPTA - the International Pulsar Timing Array project is a collaboration between several separate pulsar timing array experiments worldwide.
- GUPPI - the Green Bank Ultimate Pulsar Processing Instrument. State-of-the-art FPGA/GPU-based pulsar instrument for the GBT (GUPPI) and Arecibo (PUPPI). Records large-bandwidth, high dynamic range, full-Stokes data in filterbank, coherent dedispersion, and baseband modes.
- PSRCHIVE - Data analysis software for pulsar timing, calibration and polarimetry.
- DSPSR - Data analysis software for baseband pulsar data, coherent dedispersion, cyclic spectroscopy, etc.
- TEMPO - the "classic" data analysis software for pulsar timing.
presentations
- Tutorial: GPUs in Radio Astronomy from USNC-URSI meeting, Boulder, CO, January 2012.
- Testing Physics with Millisecond Pulsars, given at various colloquia in 2011.
code
- My github account includes all the following packages, and a few assorted other things.
- guppi_daq - the data aquisition code for GUPPI (P. Demorest, S. Ransom)
- Cyclic-Modelling - program for modelling/descattering pulsar cyclic spectra (M. Walker, P. Demorest)
- vdifio - library for parsing VDIF data (A. Deller)