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Primordial bispectrum and trispectrum contributions to the non-Gaussian excursion set halo mass function with diffusive drifting barrier

“…As shown in Ref. [23] for the case of primordial bispectrum, these tests can provide improved constraints on primordial non-Gaussianity from the upcoming generation of cosmic structure surveys.…”

SN 2019ewu: A Peculiar Supernova with Early Strong Carbon and Weak Oxygen Features from a New Sample of Young SN Ic Spectra

“…where the parameters are chosen to be consistent with the hydrodynamical simulations of an exploded stripped star (Iwamoto et al 1994) that have been used for radiative transfer simulations of SN Ic 1994I (Hachinger et al 2012;Williamson et al 2021). We keep the exponent n = −6.78 fixed (fit from the outer layers of the hydrodynamical simulation) but vary the normalization parameter ρ 0 to experiment with different ejecta masses.…”

“…It is particularly important to explain the P Cygni-shaped feature highlighted in the shaded region of the left panel of Figure 5 because this could be evidence of hydrogen. There has been some discussion in the literature of hydrogen potentially contributing to the spectral features of SN Ic 1994I (Hachinger et al 2012;Parrent et al 2016), but there has not been a confident identification of hydrogen features in an SN Ic backed by modeling. The prevailing theory is that SNe Ic progenitors are highly stripped due to binary interactions (Podsiadlowski et al 1992;Yoon 2015) or strong winds from massive single stars (Crowther 2007;Smartt 2009) such that they have lost their hydrogen envelopes (Schneider et al 2021;Woosley et al 2021).…”

Beyond the helium buffer: 12C−2 rotational cooling in cold traps with H2 as a partner gas: interaction forces and quantum dynamics

“…This 4D to 2D reduction of the PES is physically equivalent to restricting the H 2 molecule to be only the parahydrogen in its j = 0 level and has been already used in the past for various other systems [51][52][53][54]. For the temperatures of interest in this work (T ≤ 100 K), the probability of exciting the H 2 molecule is low as the energy spacing between the j = 0 and j = 2 levels of parahydrogen is around 500 K [51].…”

“…This 4D to 2D reduction of the PES is physically equivalent to restricting the H 2 molecule to be only the parahydrogen in its j = 0 level and has been already used in the past for various other systems [51][52][53][54]. For the temperatures of interest in this work (T ≤ 100 K), the probability of exciting the H 2 molecule is low as the energy spacing between the j = 0 and j = 2 levels of parahydrogen is around 500 K [51]. This approximation has been checked for its accuracy: for SiS/H 2 collisions a 4D vs 2D treatment only resulted in differences of around 10 % in the scattering cross-sections [52] and for HNC/H 2 collisions the approximate treatment resulted in crosssections within a factor of two of the 4D treatment while rates differed by less than 30 % [53].…”