Peter M. Challis

Evolution of the Reverse Shock Emission from SNR 1987A (2006)

Heng, Kevin, McCray, Richard, Zhekov, Svetozar A., Challis, Peter M., Chevalier, Roger A., Crotts, Arlin P. S., ...

We present new (2004 July) G750L and G140L Space Telescope Imaging Spectrograph (STIS) data of the H-alpha and Ly-alpha emission from supernova remnant (SNR) 1987A. With the aid of earlier data, from...

The Type IIn Supernova 2002kg: The Outburst of a Luminous Blue Variable Star in NGC 2403 (2006)

Van Dyk, Schuyler D., Li, Weidong, Filippenko, Alexei V., Humphreys, Roberta M., Chornock, Ryan, Foley, Ryan, ...

We show that Supernova (SN) 2002kg in NGC 2403, initially classified as Type II-narrow (IIn), has photometric and spectroscopic properties unlike those of normal SNe. Its behavior, instead, is more...

Cepheid Calibrations from the Hubble Space Telescope of the Luminosity of Two Recent Type Ia Supernovae and a Re-determination of the Hubble Constant (2005)

Riess, Adam G., Li, Weidong, Stetson, Peter B., Filippenko, Alexei V., Jha, Saurabh, Kirshner, Robert P., ...

We report observations of two nearby Type Ia supernovae (SNe Ia) for which observations of Cepheid variables in the host galaxies have been obtained with the Hubble Space Telescope: SN 1994ae in NGC...

Hubble Space Telescope and Ground-Based Observations of SN 1993J and SN 1998S: CNO Processing in the Progenitors (2004)

Fransson, Claes, Challis, Peter M., Chevalier, Roger A., Filippenko, Alexei V., Kirshner, Robert P., Kozma, Cecilia, ...

Ground-based and Hubble Space Telescope observations are presented for SN 1993J and SN 1998S. SN 1998S shows strong, relatively narrow circumstellar emission lines of N III-V and C III-IV, as well as...

A Study of the Type II-Plateau Supernova 1999gi, and the Distance to its Host Galaxy, NGC 3184 (2002)

Leonard, Douglas C., Filippenko, Alexei V., Li, Weidong, Matheson, Thomas, Kirshner, Robert P., Chornock, Ryan, ...

We present optical spectra and photometry sampling the first six months after discovery of supernova (SN) 1999gi in NGC 3184. SN 1999gi is shown to be a Type II-plateau event with a photometric...

Modelling the Hubble Space Telescope Ultraviolet and Optical Spectrum of Spot 1 on the Circumstellar Ring of SN 1987A (2002)

Pun, Chun S. J., Michael, Eli, Zhekov, Svetozar A., McCray, Richard, Garnavich, Peter M., Challis, Peter M., ...

We report and interpret HST/STIS long-slit observations of the optical and ultraviolet (1150 - 10270 Angstrom) emission-line spectra of the rapidly brightening Spot 1 on the equatorial ring of SN...

Hubble Space Telescope Spectroscopic Observations of the Ejecta of SN 1987A at 2000 Days (1996)

Wang, Lifan, Wheeler, J. Craig, Kirshner, Robert P., Challis, Peter M., Filippenko, Alexei V., Fransson, Claes, ...

We have used the Faint Object Spectrograph on the Hubble Space Telescope to observe the spectra of SN 1987A over the wavelength range 2000 -- 8000\ \AA\ on dates 1862 and 2210 days after the...