Astronomy: Galaxy evolution at late epochs

ASTRONOMY AND ASTROPHYSICS Galaxy coordinates I . Accuracy

Using a generalization of the triple intercomparison method introduced by de Vaucouleurs and Head we calculated the accuracy of galaxy coordinates taken from the large catalogues. The result confirms the qualitative estimation we had in mind about the different catalogues, but for the first time it will be now possible to give a quantitative estimation of the accuracy of the position of individ...

Astronomy & Astrophysics The H α galaxy survey

We discuss the selection and observations of a large sample of nearby galaxies, which we are using to quantify the star formation activity in the local Universe. The sample consists of 334 galaxies across all Hubble types from S0/a to Im and with recession velocities of between 0 and 3000 km s−1. The basic data for each galaxy are narrow band Hα+[N] and R-band imaging, from which we derive st...

Galaxy Evolution

The Evolution of Neutrino Astronomy

The possibility of observing solar neutrinos began to be discussed seriously following the 1958 experimental discovery by Holmgren and Johnston that the cross section for production of the isotope Be by the fusion reaction He + He → Be+ γ was more than a thousand times larger than was previously believed. This result led Willy Fowler and Al Cameron to suggest that B might be produced in the sun...

ASTRONOMY AND ASTROPHYSICS Epochs of Maximum Light and Bolometric Light Curves of Type Ia Supernovae

We present empirical fits to the UBVRI light curves of type Ia supernovae. These fits are used to objectively evaluate light curve parameters. We find that the relative times of maximum light in the filter passbands are very similar for most objects. Surprisingly the maximum at longer wavelengths is reached earlier than in the B and V light curves. This clearly demonstrates the complicated natu...