scholarly journals Dust Emission Spectra of the Nova V1112 Persei

2021 ◽  
Vol 5 (11) ◽  
pp. 273
Author(s):  
Richard J. Rudy ◽  
Ray W. Russell ◽  
Michael L. Sitko
Keyword(s):  
Infrared Spectra ◽  
Dust Emission ◽  
Emission Spectra ◽  
Emission Lines ◽  
Line Of Sight ◽  
Dust Formation

Abstract Infrared spectra of the dusty nova V1112 Persei (Nova Persei 2020) are presented from 29 and 48 days after the onset of dust formation, the later epoch corresponding to when obscuration by the nova dust was at a maximum. The dust emission was featureless and had temperatures of approximately 880 K and 690 K for the two epochs, respectively. Some dust formed along the line of sight and the total extinction for V1112 Per increased from E(B-V) = 0.8 prior to dust formation, to 1.2 on February 3, to 1.4 by February 22. Emission lines of both carbon and oxygen were present along with the dust emission indicating that the dust did not consume all of either of these element.

scholarly journals Predicting the stellar and non-equilibrium dust emission spectra of high-resolution simulated galaxies with dart-ray

2015 ◽  
Vol 449 (1) ◽  
pp. 243-267 ◽  
Author(s):  
Giovanni Natale ◽  
Cristina C. Popescu ◽  
Richard. J. Tuffs ◽  
Victor P. Debattista ◽  
Jörg Fischera ◽  
...  
Keyword(s):  
High Resolution ◽  
Dust Emission ◽  
Emission Spectra ◽  
Non Equilibrium

Luminescence of polymer electrolytes containing europium (III)

1995 ◽  
Vol 10 (1) ◽  
pp. 202-210 ◽  
Author(s):  
L.D. Carlos ◽  
M. Assunção ◽  
L. Alcácer
Keyword(s):  
Polymer Electrolytes ◽  
Morphological Changes ◽  
Emission Spectra ◽  
Emission Lines ◽  
Hypersensitive Transition ◽  
Polymeric Matrices ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene ◽  
Poly Propylene ◽  
Europium Concentration

The excitation and emission spectra of polymeric matrices—poly(ethylene oxide), PEO, and poly(propylene oxide), PPO—containing different concentrations of EuBr3 were recorded and most of the observed transitions identified. The Stark components of the 7F0−4, 5D0 levels and the corresponding barycenters were calculated based on the emission lines assignment to the 5D0,1 → 7F0−4 transitions. The spectra were discussed in terms of a C2v local Eu3+ coordination. The relative intensity of the 5D0 → 7F2 hypersensitive transition was related to the electrolyte morphological changes due to increasing europium concentration.

scholarly journals SEDIGISM: the kinematics of ATLASGAL filaments

2018 ◽  
Vol 619 ◽  
pp. A166 ◽  
Author(s):  
M. Mattern ◽  
J. Kauffmann ◽  
T. Csengeri ◽  
J. S. Urquhart ◽  
S. Leurini ◽  
...  
Keyword(s):  
Unit Length ◽  
Dust Emission ◽  
Free Fall ◽  
Outer Radius ◽  
Line Of Sight ◽  
Fall Velocity ◽  
Automated Algorithm ◽  
Power Law Exponent ◽  
Continuum Data ◽  
Self Gravity

Analyzing the kinematics of filamentary molecular clouds is a crucial step toward understanding their role in the star formation process. Therefore, we study the kinematics of 283 filament candidates in the inner Galaxy, that were previously identified in the ATLASGAL dust continuum data. The 13CO(2 – 1) and C18O(2 – 1) data of the SEDIGISM survey (Structure, Excitation, and Dynamics of the Inner Galactic Inter Stellar Medium) allows us to analyze the kinematics of these targets and to determine their physical properties at a resolution of 30′′ and 0.25 km s−1. To do so, we developed an automated algorithm to identify all velocity components along the line-of-sight correlated with the ATLASGAL dust emission, and derive size, mass, and kinematic properties for all velocity components. We find two-third of the filament candidates are coherent structures in position-position-velocity space. The remaining candidates appear to be the result of a superposition of two or three filamentary structures along the line-of-sight. At the resolution of the data, on average the filaments are in agreement with Plummer-like radial density profiles with a power-law exponent of p ≈ 1.5 ± 0.5, indicating that they are typically embedded in a molecular cloud and do not have a well-defined outer radius. Also, we find a correlation between the observed mass per unit length and the velocity dispersion of the filament of m ∝ σv2. We show that this relation can be explained by a virial balance between self-gravity and pressure. Another possible explanation could be radial collapse of the filament, where we can exclude infall motions close to the free-fall velocity.

scholarly journals Simulation study for the Stratospheric Inferred Winds (SIW) sub-millimeter limb sounder

2018 ◽  
Author(s):  
Philippe Baron ◽  
Donal Murtagh ◽  
Patrick Eriksson ◽  
Jana Mendrok ◽  
Satoshi Ochiai ◽  
...  
Keyword(s):  
Simulation Study ◽  
Spectral Band ◽  
Chemical Species ◽  
Field Of View ◽  
Emission Lines ◽  
Horizontal Wind ◽  
Line Of Sight ◽  
Heterodyne Receiver ◽  
Vertical Field ◽  
Wind Measurements

Abstract. Stratospheric Inferred Winds (SIW) is a Swedish mini sub-millimeter limb sounder selected for the 2nd InnoSat platform launch planned near 2022. It is intended to fill the altitude gap between 30–70 km in atmospheric wind measurements and also aims at pursuing the limb observations of temperature and key atmospheric constituents between 10–90 km when current satellite missions are probably stopped. Line-of-sight winds are retrieved from the Doppler shift of the emission lines introduced by 5 the wind field. Observations will be performed with two antennas pointing toward the limb with perpendicular directions to reconstruct the 2-D horizontal wind vector. Each antenna has a vertical field of view of 5 km. The chosen spectral band near 655 GHz contains a dense group of strong O3 lines suitable for exploiting the small wind information in stratospheric spectra. Using both sidebands of the heterodyne receiver, a large number of chemical species will be measured including O3-isopotologues, H2O, HDO, HCl, ClO, N2O, HNO3, NO, NO2, HCN, CH3CN and HO2. This paper presents the simulation study for assessing the measurement performances. The line-of-sight winds are retrieved between 30–90 km with the best sensitivity between 35–70 km where the precision (1-sigma) is 5–10 m s−1 for a single scan. Similar performances can be obtained during day and night conditions except in the lower mesosphere where the photo-dissociation of O3 in day-time reduces the sensitivity by 50 % near 70 km. Profiles of O3, H2O and temperature are retrieved with a high precision up to 50 km (

scholarly journals Kinematic distances for southern pulsars: Gum & Carina

1996 ◽  
Vol 160 ◽  
pp. 479-480
Author(s):  
Bärbel Koribalski ◽  
Simon Johnston ◽  
Joel Weisberg
Keyword(s):  
Interstellar Medium ◽  
Emission Spectra ◽  
Line Of Sight ◽  
Dispersion Measure ◽  
Absorption And Emission ◽  
Absorption And Emission Spectra ◽  
Gum Nebula ◽  
Absorption Measurements

We have observed 21-cm absorption and emission spectra in the direction of about 20 southern pulsars with the Parkes telescope to derive their kinematic distances and to study the interstellar medium. In each case we thoroughly investigated the environment of each pulsar as well as sources along the line of sight which may contribute to the pulsars’ dispersion measure (DM).Some of the results, which are published in Koribalski et al. (1995) and Johnston et al. (1996), are included in the compilation of Hi absorption measurements by Joel Weisberg in this volume. In the following we present a detailed discussion on pulsars toward 1) the Gum Nebula and 2) the Carina Arm.

scholarly journals Quasars Disks and Cosmology

1987 ◽  
Vol 124 ◽  
pp. 695-696
Author(s):  
Hagai Netzer
Keyword(s):  
Black Hole ◽  
Ultraviolet Radiation ◽  
Equivalent Width ◽  
Selection Effect ◽  
Emission Lines ◽  
Line Of Sight ◽  
Apparent Brightness ◽  
Central Black Hole ◽  
New Ideas ◽  
Thin Disks

Much of the optical and ultraviolet radiation of bright quasars may originate in a massive accretion disk around a central black hole. Most searches for the signature of such disks gave ambiguous results but lately there are new ideas that may lead to their discovery. In particular, the apparent brightness of thin disks depend on their inclination to the observer's line of sight and this may be detected by the equivalent width of some emission lines (Netzer 1985, 1986). This idea may change our view on the inner structure of quasars and other AGN. In addition, it points to a potential selection effect that has not been taken into account so far. Magnitude limited optical quasar samples may contain, preferentially, face-on disks, thus cosmological evolution based on such samples may be biased. There are other implications, especially to the observed correlation of Lop with Lx in quasars.

Emission spectroscopy as a noninvasive probe for process control during radio frequency sputter deposition of PbTe

1989 ◽  
Vol 67 (4) ◽  
pp. 287-293 ◽  
Author(s):  
J. G. Cook ◽  
M. S. Aouadi ◽  
S. R. Das
Keyword(s):  
Electron Temperature ◽  
Emission Spectroscopy ◽  
Emission Spectra ◽  
Sputter Deposition ◽  
Emission Lines ◽  
Substrate Bias ◽  
Rf Power ◽  
Magnetron Discharge ◽  
Substrate Bias Voltage ◽  
Pressure Changes

An rf magnetron discharge used to sputter PbTe in Ar is analyzed using emission spectroscopy. The intensity (I) of the strong Pb, Te, and Ar emission lines is determined near the target and near the substrate as the rf power or gas pressure is varied. It is shown that as the rf power is varied at pressures below 0.5 Pa, the electron temperature is not affected, so that the sputtered atom density NPb is proportional to IPb/IAr. The electron temperature is, however, sensitive to pressure changes. Application of a substrate bias voltage has a large effect on the emission spectra which are not understood.

scholarly journals Carbonaceous nano-dust emission in proto-planetary discs: the aliphatic-aromatic components

2019 ◽  
Vol 623 ◽  
pp. A135 ◽  
Author(s):  
T. Boutéraon ◽  
E. Habart ◽  
N. Ysard ◽  
A. P. Jones ◽  
E. Dartois ◽  
...  
Keyword(s):  
Adaptive Optics ◽  
Interstellar Dust ◽  
Near Infrared ◽  
Solid Phase ◽  
Dust Emission ◽  
Emission Spectra ◽  
Infrared Emission ◽  
Constant Intensity ◽  
Aromatic Components ◽  
Nano Grains

Context. In the interstellar medium, carbon (nano-)grains are a major component of interstellar dust. This solid phase is more vulnerable to processing and destruction than its silicate counterpart. It exhibits a complex, size-dependent evolution that is due to interactions within different radiative and dynamical environments. Infrared signatures of these carbon nano-grains are seen in a large number of discs around Herbig HAeBe stars. Aims. We probe the composition and evolution of carbon nano-grains at the surface of (pre-)transitional proto-planetary discs around Herbig stars. Methods. We present spatially resolved infrared emission spectra obtained with the Nasmyth Adaptive Optics System (NAOS) Near-Infrared Imager and Spectrograph (CONICA) at the Very Large Telescope (VLT) in the 3–4 μm range with a spatial resolution of 0.1′′, which allowed us to trace aromatic, olefinic, and aliphatic bands that are attributed to sub-nanometer hydrocarbon grains. We applied a Gaussian fitting to analyse the observed spectral signatures. Finally, we propose an interpretation in the framework of the The Heterogeneous dust Evolution Model of Interstellar Solids (THEMIS). Results. We show the presence of several spatially extended spectral features that are related to aromatic and aliphatic hydrocarbon material in discs around Herbig stars, from ~10 to 50–100 au, and even in inner gaps that are devoid of large grains. The correlation and constant intensity ratios between aliphatic and aromatic CH stretching bands suggests a common nature of the carriers. Given their expected high destruction rates through UV photons, our observations suggest that they are continuously replenished at the disc surfaces.

scholarly journals Shock Excitation of Emission Lines in Radio Galaxies

1996 ◽  
Vol 175 ◽  
pp. 473-474
Author(s):  
A. M. Koekemoer ◽  
G. V. Bicknell
Keyword(s):  
Physical Mechanism ◽  
Radio Galaxies ◽  
Emission Lines ◽  
Line Of Sight ◽  
Ionization Mechanism ◽  
Unknown Parameters ◽  
Radio Lobe ◽  
Axis Alignment ◽  
Gas Interactions ◽  
Extended Emission

We present evidence for the viability of “auto-ionizing” shocks as the dominant ionization mechanism in extended emission-line regions (EELRs) in two radio galaxies, PKS 0349–27 and PKS 2356–61. The application of this model, rather than the nuclear photoionization hypothesis of unified schemes (Barthel 1989), is motivated by observed EELR properties: large line-of-sight velocity widths (up to δv ≃ 500 km s–1 for nearby objects and ≳ 1000kms–1 at higher z); kinematics/excitation relationships (Baum et al. 1992); the EELR/radio axis alignment (Chambers et al. 1987, McCarthy et al. 1987); and the correspondence between the brighter EELR and the shorter radio lobe (McCarthy et al. 1991), suggestive of jet/gas interactions. We show that the flux, excitation and kinematics across the gas is self-consistently accounted for in terms of shocks as a single physical mechanism, requiring fewer unknown parameters than nuclear photoionization.

scholarly journals Behaviour of Hα and H Ca II Emission Lines in a Prominence Before and During its Dynamic “Disparition Brusque”

1998 ◽  
Vol 167 ◽  
pp. 326-329
Author(s):  
M.S. Madjarska ◽  
V.N. Dermendjiev ◽  
Z. Mouradian ◽  
P. Kotrč
Keyword(s):  
Emission Lines ◽  
Line Of Sight ◽  
Quiescent Prominence ◽  
Temperature Line

AbstractHα and H Ca II emission lines in a limb quiescent prominence (QP) undergoing destabilization are studied. The temperature, line-of-sight velocity and micro-turbulence are obtained in one of the prominence legs, just before and during the prominence activation.

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