We introduce the strong CP problem and the existence of the Axion as a possible solution. We discuss the possibility that axions are the dark matter of the...
The relative role of AGB stars and SNe as the first cosmic dust polluters
Far infrared and sub-millimeter observations of quasars and normal star forming galaxies at z>6 have revealed the presence of large amounts of dust. At such...
The SN Ia runaway LP 398-9: detection of circumstellar material and surface rotation
A promising progenitor scenario for Type Ia supernovae (SNeIa) is the thermonuclear detonation of a white dwarf in a close binary system with another white...
The Type II-plateau Supernova 2017eaw in NGC 6946 and Its Red Supergiant Progenitor
We present extensive optical photometric and spectroscopic observations, from 4 to 482 days after explosion, of the Type II-plateau (II-P) supernova (SN)...
The Young, Massive, Star Cluster Sandage-96 After the Explosion of Supernova 2004dj in NGC 2403
The bright Type II-plateau supernova (SN) 2004dj occurred within the young, massive stellar cluster Sandage-96 in a spiral arm of NGC 2403. New multiwavelength...
TREASUREHUNT: Transients and Variability Discovered with HST in the JWST North Ecliptic Pole Time-domain Field
The James Webb Space Telescope (JWST) North Ecliptic Pole (NEP) Time-domain Field (TDF) is a >14' diameter field optimized for multiwavelength time-domain...
SN 1572 (Tycho Brahe’s supernova) clearly belongs to the Ia (thermonuclear) type. It was produced by the explosion of a white dwarf (WD) in a binary system. Its...
Type Ia supernovae with and without blueshifted narrow Na I D lines - how different is their structure?
In studies on intermediate- and high-resolution spectra of Type Ia supernovae (SNe Ia), some objects exhibit narrow Na I D absorptions often blueshifted with...