Nat Butler
578 Goldwater Building
School of Earth and Space Exploration
Arizona State University
PO Box 871404
Tempe, AZ 85287-1404
EMAIL: natbutler[at]asu[dot]edu

CV   -   Publications

Nat Butler studies astrophysical transients. He observes the optical, IR, X-, and Gamma-ray emission from Gamma-ray Bursts (GRBs) and their afterglows in order to study the physics of jetting, the afterglow emission mechanisms, the nature of the progenitors, and potentially to use GRBs as cosmology probes. He is also an experimentalist focusing on robotic telescopes, data mining, and novel technologies for transient detection and followup.

Experimental Projects

I am leading RATIR: the Reionization And Transients InfraRed camera project. This pathfinder to SASIR is a 6-channel simultaneous optical/NIR imager now under construction which is to be dedicated to GRB followup and the detection of high-z GRB afterglows.

SASIR The Synoptic All-Sky InfraRed survey, a joint project between the US and Mexico to build a 6.5m telescope in Baja California that will repeatedly image the entire sky to a level 100-500 times deeper than 2MASS.

C3P0Cam : The CMOS 3-Color Prototype #0 Camera. An optical imaging camera designed for high-time cadence, multi-color observations of transient sources. The camera was tested using the 1m Nickel Telescope at Lick Observatory.


Astronomical Surveys and Data Mining

Optimal Time-Series Selection of Quasars: Software tools and study using Sloan Stripe 82 data to separate quasars from stars using data from a single (optical) photometric bandpass. Also, period finding code for QSOs.

Berkeley TCP: Transients Classification Pipeline. The Transients Classification Pipeline (TCP) is a parallelized, Python-based framework created to identify and classify transient sources, beginning with sources from PTF.

PTF: The Palomar Transients Factory. PTF is a new wide field, multiple cadence transient survey utilizing a 7.8 square degree CCD array newly placed on the 48" Oshin Telescope at Palomar Observatory.

Swift Observations and Downloadable Reduced Data Products

Swift observes with unprecedented detail GRBs and their early afterglows.

I have an online repository for XRT and BAT lightcurves and spectra, including tables of XRT spectral fits , BAT spectral fits and BAT temporal fits. Astrometry-corrected positions for Swift XRT X-ray afterglows can be found here as well.

Electronic tables of the BAT fits from Butler et al. (2007; ApJ, 671, 656) can be found here in FITS format. Updated results from Butler et al. (2010; ApJ, 711, 495) can be found here. Similar fits are computed and updated in real-time at the the repository site above.


The Fermi Gamma-ray Space Telescope (formerly GLAST) launched successfully in June and is now detecting GRBs with both the GBM and LAT.