Pilar Ruiz-Lapuente

The Chemical Abundances of Tycho G in Supernova Remnant 1572 (2009)

González Hernández, Jonay I., Ruiz-Lapuente, Pilar, Filippenko, Alexei V., Foley, Ryan J., Gal-Yam, Avishay, Simon, Joshua D.

We present an analysis of the chemical abundances of the star Tycho G in the direction of the remnant of supernova (SN) 1572, based on Keck high-resolution optical spectra. The stellar parameters of...

The Chemical Abundances of Tycho G in Supernova Remnant 1572 (2008)

Hernández, Jonay I. González, Ruiz-Lapuente, Pilar, Filippenko, Alexei V., Foley, Ryan J., Gal-Yam, Avishay, Simon, Joshua D.

We present an analysis of the chemical abundances of the star Tycho G in the direction of the remnant of supernova (SN) 1572, based on Keck high-resolution optical spectra. The stellar parameters of...

Tracing the equation of state and the density of cosmological constant along z (2008)

Espana-Bonet, Cristina, Ruiz-Lapuente, Pilar

We investigate the equation of state w(z) in a non-parametric form using the latest compilations of distance luminosity from SNe Ia at high z. We combine the inverse problem approach with a Monte...

Dark energy, gravitation and supernovae (2007)

Ruiz-Lapuente, Pilar

The discovery of the acceleration of the rate of expansion of the Universe fosters new explorations of the behavior of gravitation theories in the cosmological context. Either the GR framework is...

Dark Energy as an Inverse Problem (2005)

Espana-Bonet, Cristina, Ruiz-Lapuente, Pilar

A model--independent approach to dark energy is here developed by considering the determination of its equation of state as an inverse problem. The reconstruction of w(z) as a non--parametric...

The binary progenitor of Tycho Brahe's 1572 supernova (2004)

Ruiz-Lapuente, Pilar, Comeron, Fernando, Mendez, Javier, Canal, Ramon, Smartt, Stephen J., Filippenko, Alexei V., ...

The brightness of type Ia supernovae, and their homogeneity as a class, makes them powerful tools in cosmology, yet little is known about the progenitor systems of these explosions. They are thought...

Testing the running of the cosmological constant with Type Ia Supernovae at high z (2003)

Espana-Bonet, Cristina, Ruiz-Lapuente, Pilar, Shapiro, Ilya L., Sola, Joan

Within the Quantum Field Theory context the idea of a "cosmological constant" (CC) evolving with time looks quite natural as it just reflects the change of the vacuum energy with the typical energy...

Tycho Brahe's supernova: light from centuries past (2003)

Ruiz-Lapuente, Pilar

The light curve of SN 1572 is described in the terms used nowadays to characterize SNeIa. By assembling the records of the observations done in 1572--74 and evaluating their uncertainties, it is...

Variable Cosmological Constant as a Planck Scale Effect (2003)

Shapiro, Ilya L., Sola, Joan, Espana-Bonet, Cristina, Ruiz-Lapuente, Pilar

We construct a semiclassical FLRW cosmological model assuming a running cosmological constant (CC). It turns out that the CC becomes variable at arbitrarily low energies due to the remnant quantum...

Optical Photometry of GRB 021004: The First Month (2002)

Holland, Stephen T., Weidinger, Michael, Fynbo, Johan P. U., Gorosabel, Javier, Hjorth, Jens, Pedersen, Kristian, ...

We present U,B,V,R_C,and I_C photometry of the optical afterglow of the gamma-ray burst GRB 021004 taken at the Nordic Optical Telescope between approximately eight hours and 30 days after the burst....

Reclassification of gamma-ray bursts (2001)

Balastegui, Andreu, Ruiz-Lapuente, Pilar, Canal, Ramon

We have applied two different automatic classifier algorithms to the BATSE Current GRB Catalog data and we obtain three different classes of GRBs. Our results confirm the existence of a third,...

The late emission of thermonuclear supernovae (1996)

Ruiz-Lapuente, Pilar

The subject of late-time emission of Type Ia supernovae and its implications for the understanding of the explosions of C+O WDs is reviewed.

The Hubble constant from $^{56}$Co-powered Nebular Candles (1996)

Ruiz-Lapuente, Pilar

Type Ia supernovae (SNe Ia), produced by the thermonuclear explosion of white dwarf (WD) stars, are used here to derive extragalactic distances and an estimate of the Hubble constant from their...

SN~1991T: Reflections of Past Glory (1994)

Schmidt, Brian P., Kirshner, Robert P., Leibundgut, Bruno, Wells, Lisa A., Porter, Alain C., Ruiz-Lapuente, Pilar, ...

We have obtained photometry and spectra of SN~1991T which extend more than 1000 days past maximum light, by far the longest a SN~Ia has been followed. Although SN~1991T exhibited nearly normal...