F. Salgado | Others - Academia.edu (original) (raw)
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Papers by F. Salgado
CBET 1580 available at Central Bureau for Astronomical Telegrams.
The Astrophysical Journal, 2012
The massive star forming region W3 was observed with the faint object infrared camera for the SOF... more The massive star forming region W3 was observed with the faint object infrared camera for the SOFIA telescope (FORCAST) as part of the Short Science program. The 6.4, 6.6, 7.7, 19.7, 24.2, 31.5 and 37.1 µm bandpasses were used to observe the emission of Polycyclic Aromatic Hydrocarbon (PAH) molecules, Very Small Grains and Big Grains. Optical depth and color temperature maps of W3A show that IRS2 has blown a bubble devoid of gas and dust of ∼0.05 pc radius. It is embedded in a dusty shell of ionized gas that contributes 40% of the total 24 µm emission of W3A. This dust component is mostly heated by far ultraviolet, rather than trapped Lyα photons. This shell is itself surrounded by a thin (∼0.01 pc) photodissociation region where PAHs show intense emission. The infrared spectral energy distribution (SED) of three different zones located at 8, 20 and 25 ′′ from IRS2, show that the peak of the SED shifts towards longer wavelengths, when moving away from the star. Adopting the stellar radiation field for these three positions, DUSTEM model fits to these SEDs yield a dust-to-gas mass ratio in the ionized gas similar to that in the diffuse ISM. However, the ratio of the IR-to-UV opacity of the dust in the ionized shell is increased by a factor ≃3 compared to the diffuse ISM.
The Carnegie Supernova Project is a five year survey being carried out at the Las Campanas Observ... more The Carnegie Supernova Project is a five year survey being carried out at the Las Campanas Observatory to obtain high-quality light curves of 100 low-redshift Type Ia supernovae in a well-defined photometric system. In this paper, we present the first release of photometric data that contains the optical (ugriBV) light curves of 35 Type Ia supernovae, and near-infrared (YJHKs) light
Monthly Notices of the Royal Astronomical Society, 2011
Monthly Notices of the Royal Astronomical Society, 2011
Astronomy & Astrophysics, 2013
We report a Herschel detection of high-J rotational CO lines from a dense knot in the supernova r... more We report a Herschel detection of high-J rotational CO lines from a dense knot in the supernova remnant Cas A. Based on a combined analysis of these rotational lines, and previously observed ro-vibrational CO lines, we find the gas to be warm (two components at ∼400 and 2000 K) and dense (10 6-7 cm −3 ), with a CO column density of ∼5×10 17 cm −2 . This, along with the broad line widths (∼400 km s −1 ), suggests that the CO emission originates in the post-shock region of the reverse shock. As the passage of the reverse shock dissociates any existing molecules, the CO has most likely reformed in the last few years, in the post-shock gas. The CO cooling time is comparable to the CO formation time, so possible heating sources (UV photons from the shock front, X-rays, electron conduction) to maintain the large column density of warm CO are discussed.
CBET 1580 available at Central Bureau for Astronomical Telegrams.
The Astrophysical Journal, 2012
The massive star forming region W3 was observed with the faint object infrared camera for the SOF... more The massive star forming region W3 was observed with the faint object infrared camera for the SOFIA telescope (FORCAST) as part of the Short Science program. The 6.4, 6.6, 7.7, 19.7, 24.2, 31.5 and 37.1 µm bandpasses were used to observe the emission of Polycyclic Aromatic Hydrocarbon (PAH) molecules, Very Small Grains and Big Grains. Optical depth and color temperature maps of W3A show that IRS2 has blown a bubble devoid of gas and dust of ∼0.05 pc radius. It is embedded in a dusty shell of ionized gas that contributes 40% of the total 24 µm emission of W3A. This dust component is mostly heated by far ultraviolet, rather than trapped Lyα photons. This shell is itself surrounded by a thin (∼0.01 pc) photodissociation region where PAHs show intense emission. The infrared spectral energy distribution (SED) of three different zones located at 8, 20 and 25 ′′ from IRS2, show that the peak of the SED shifts towards longer wavelengths, when moving away from the star. Adopting the stellar radiation field for these three positions, DUSTEM model fits to these SEDs yield a dust-to-gas mass ratio in the ionized gas similar to that in the diffuse ISM. However, the ratio of the IR-to-UV opacity of the dust in the ionized shell is increased by a factor ≃3 compared to the diffuse ISM.
The Carnegie Supernova Project is a five year survey being carried out at the Las Campanas Observ... more The Carnegie Supernova Project is a five year survey being carried out at the Las Campanas Observatory to obtain high-quality light curves of 100 low-redshift Type Ia supernovae in a well-defined photometric system. In this paper, we present the first release of photometric data that contains the optical (ugriBV) light curves of 35 Type Ia supernovae, and near-infrared (YJHKs) light
Monthly Notices of the Royal Astronomical Society, 2011
Monthly Notices of the Royal Astronomical Society, 2011
Astronomy & Astrophysics, 2013
We report a Herschel detection of high-J rotational CO lines from a dense knot in the supernova r... more We report a Herschel detection of high-J rotational CO lines from a dense knot in the supernova remnant Cas A. Based on a combined analysis of these rotational lines, and previously observed ro-vibrational CO lines, we find the gas to be warm (two components at ∼400 and 2000 K) and dense (10 6-7 cm −3 ), with a CO column density of ∼5×10 17 cm −2 . This, along with the broad line widths (∼400 km s −1 ), suggests that the CO emission originates in the post-shock region of the reverse shock. As the passage of the reverse shock dissociates any existing molecules, the CO has most likely reformed in the last few years, in the post-shock gas. The CO cooling time is comparable to the CO formation time, so possible heating sources (UV photons from the shock front, X-rays, electron conduction) to maintain the large column density of warm CO are discussed.