Related papers: Tracking the evolutionary stage of protostars by t…
We review the use of young low mass stars and protostars, or young stellar objects (YSOs), as tracers of star formation. Observations of molecular clouds at visible, infrared, radio and X-ray wavelengths can identify and characterize the…
Context. Interstellar ice is the main form of metal species in dark molecular clouds. Experiments and observations have shown that the ice is significantly processed after the freeze-out of molecules onto grains. The processing is caused by…
We investigate the effects produced mainly by broadband soft X-rays up to 2 keV (plus fast (keV) photoelectrons and low-energy (eV) induced secondary electrons) in the ice mixtures containing H2O:CO2:NH3:SO2 (10:1:1:1) at two different…
We investigate the chemical evolution of a collapsing core that starts from a hydrostatic core and finally form a low-mass protostar. New multiphase gas-grain models that include bulk diffusion and photon penetration are simulated by the…
Ice chemistry in the dense, cold interstellar medium (ISM) is probably responsible for the formation of interstellar complex organic molecules (COMs). Recent laboratory experiments performed at T=4 K have shown that irradiation of CO:N2 ice…
Context: Compared to Class 0 protostars, the higher densities and lower temperatures of the disk midplanes of Class I young stellar objects (YSOs) limit the detectability of complex organic molecules (COMs). The elevated luminosities of…
We use various analytical techniques to study Young Stellar Objects (YSOs) in an area of approximately $10' \times 10'$ in the IRAS 18456-0223 star-forming region. We use archival optical (Gaia DR3) and infrared (2MASS, UKIDSS, Spitzer,…
We have investigated the two-dimensional (R,Z) distribution of deuterated molecular species in circumstellar disks around young stellar objects. The abundance ratios between singly deuterated and normal molecules (``D/H ratios'') in disks…
Measured properties of young stellar objects (YSOs) are key tools for research into pre-main-sequence stellar evolution. YSO properties are commonly measured by comparing observed radiation to existing grids of template YSO spectral energy…
Gas plays a major role in the dynamical evolution of young stellar objects. Its interaction with the dust is the key to our understanding planet formation later on in the protoplanetary disc stage. Studying the gas content is a crucial step…
Formic acid (HCOOH) and carbon dioxide (CO2) are simple species that have been detected in the interstellar medium. The solid-state formation pathways of these species under experimental conditions relevant to prestellar cores are primarily…
Protostellar binaries harbour complex environment morphologies. Observations represent a snapshot in time, and projection and optical depth effects impair our ability to interpret them. Careful comparison with high-resolution models that…
Variability in young stellar objects (YSOs) can be caused by various time-dependent phenomena associated with star formation, including accretion rates, geometric changes in the circumstellar disks, stochastic hydromagnetic interactions…
We investigate the formation and evolution of interstellar dust-grain ices under dark-cloud conditions, with a particular emphasis on CO2. We use a three-phase model (gas/surface/mantle) to simulate the coupled gas--grain chemistry,…
Methanol and its precursor formaldehyde are among the most studied organic molecules in the interstellar medium and are abundant in the gaseous and solid phases. We recently developed a model to simulate CO hydrogenation via H atoms on…
Aims: Our aim is to understand the evolutionary sequence of high-mass star formation from the earliest evolutionary stage of high-mass starless cores, via high-mass cores with embedded low- to intermediate-mass objects, to finally high-mass…
Characterising stellar and circumstellar properties of embedded young stellar objects (YSOs) is mandatory for understanding the early stages of the stellar evolution. This task requires the combination of both spectroscopy and photometry,…
Understanding the collapse of dense molecular cloud cores to stellar densities and the subsequent evolution of the protostar is of importance to model the feedback effects such an object has on its surrounding environment, as well as…
We present a study of the evolution of the inner few astronomical units of protoplanetary disks around low-mass stars. We consider nearby stellar groups with ages spanning from 1 to 11 Myr, distributed into four age bins. Combining…
We aim to characterize the physical and chemical properties of fragmented cores during the earliest evolutionary stages in the very young star-forming regions ISOSS J22478+6357 and ISOSS J23053+5953. NOEMA 1.3 mm data are used in…