Related papers: Solar Activity and Cloud Opacity Variations: A Mod…
The IceCube Observatory provides our highest-statistics picture of the cosmic-ray arrival directions in the Southern Hemisphere, with over 700 billion cosmic-ray-induced muon events collected between May 2011 and May 2022. Using the larger…
We perform a homogeneous analysis of the Fe/Ni abundance ratio in eight Galactic planetary nebulae (PNe) and three Galactic H II regions that include the Orion nebula, where we study four nebular zones and one shocked region. We use [Fe…
The specific star-formation rate of star-forming `main sequence' galaxies significantly decreased since z~1.5, due to the decreasing molecular gas fraction and star formation efficiency. However, the radio-infrared (IR) correlation has not…
Optically dense clouds in the interstellar medium composed predominantly of molecular hydrogen, known as molecular clouds, are sensitive to energy injection in the form of photon absorption, cosmic-ray scattering, and dark matter (DM)…
Cosmic rays (CRs) at sub-TeV energies play a fundamental role in the chemical and dynamical evolution of molecular clouds, as they control the ionisation, dissociation, and excitation of H$_{2}$. Their characterisation is important both for…
With the high-resolution spectroscopy now available in the optical and satellite UV, it is possible to determine the neutral/ionized column density ratios for several different elements in a single cloud. Assuming ionization equilibrium for…
Stars and planets form within cold, dark molecular clouds. In these dense regions, where starlight cannot penetrate, cosmic rays (CRs) are the dominant source of ionization -- driving interstellar chemistry(Dalgarno (2006, PNAS, 103,…
An important factor limiting our ability to understand the production and propagation of cosmic rays pertains to the effects of heliospheric forces, commonly known as solar modulation. The solar wind is capable of generating time and…
To evaluate the capability of numerical cloud forecast as a meteorological reference for astronomical observation, we compare the cloud forecast from NCEP Global Forecast System (GFS) model for total, layer and convective cloud with…
Aims. Photodissociation by UV light is an important destruction mechanism for CO in many astrophysical environments, ranging from interstellar clouds to protoplanetary disks. The aim of this work is to gain a better understanding of the…
We study the change in cosmic-ray pressure, the change in cosmic-ray density, and the level of cosmic-ray induced heating via Alfven-wave damping when cosmic rays move from a hot ionized plasma to a cool cloud embedded in that plasma. The…
Recent deep millimeter-wave surveys attempt to measure the carbon monoxide (CO) luminosity function and mean molecular gas density through blind detections of CO emission lines. While the cosmic star formation rate density is now…
We compute a new generation of standard solar models (SSMs) that includes recent updates on some important nuclear reaction rates and a more consistent treatment of the equation of state. Models also include a novel and flexible treatment…
The energy available in a solar energy powered grid is uncertain due to the weather conditions at the time of generation. Forecasting global solar irradiance could address this problem by providing the power grid with the capability of…
The Intergalactic Medium (IGM) contains $>$50% of the baryonic mass of the Universe, yet the mechanisms responsible for keeping the IGM ionized has not been fully explained. Hence, we investigate ion abundances from the largest blind QSO…
The use of the coronal approximation to model line emission from the solar transition region has led to discrepancies with observations over many years, particularly for Li- and Na-like ions. Studies have shown that a number of atomic…
We present an updated model of the cosmic ionizing background from the UV to the X-rays. Relative to our previous model (Faucher-Giguere et al. 2009), the new model provides a better match to a large number of up-to-date empirical…
Observations of active regions and limb prominences often show cold, dense blobs descending with an acceleration smaller than that of free fall. The dynamics of these condensations falling in the solar corona is investigated in this paper…
Context: How do molecular clouds form out of the atomic phase? And what are the relative fractions of carbon in the ionized, atomic and molecular phase? These are questions at the heart of cloud and star formation. Methods: Using multiple…
Some of the natural variability in climate is understood to come from changes in the Sun. A key route whereby the Sun may influence surface climate is initiated in the tropical stratosphere by the absorption of solar ultraviolet (UV)…