- ID:
- ivo://CDS.VizieR/J/A+A/635/A156
- Title:
- Total lunar eclipse January 2019 spectra
- Short Name:
- J/A+A/635/A156
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Observations of the Earthshine o the Moon allow for the unique opportunity to measure the large-scale Earth atmosphere. Another opportunity is realized during a total lunar eclipse which, if seen from the Moon, is like a transit of the Earth in front of the Sun. We thus aim at transmission spectroscopy of an Earth transit by tracing the solar spectrum during the total lunar eclipse of January 21, 2019. Time series spectra of the Tycho crater were taken with the Potsdam Echelle Polarimetric and Spectroscopic Instrument (PEPSI) at the Large Binocular Telescope (LBT) in its polarimetric mode in Stokes IQUV at a spectral resolution of 130000 (0.06{AA}). In particular, the spectra cover the red parts of the optical spectrum between 7419-9067{AA}. The spectrograph's exposure meter was used to obtain a light curve of the lunar eclipse. The brightness of the Moon dimmed by 10.75m during umbral eclipse. We found both branches of the O_2_ A-band almost completely saturated as well as a strong increase of H_2_O absorption during totality. A pseudo O_2_ emission feature remained at a wavelength of 7618{AA}, but it is actually only a residual from different P-branch and R-branch absorptions. It nevertheless traces the eclipse. The deep penumbral spectra show significant excess absorption from the NaI 5890{AA} doublet, the CaII infrared triplet around 8600{AA}, and the KI line at 7699{AA} in addition to several hyper-fine-structure lines of MnI and even from BaII. The detections of the latter two elements are likely due to an untypical solar center-to-limb eect rather than Earth's atmosphere. The absorption in CaII and KI remained visible throughout umbral eclipse. Our radial velocities trace a wavelength dependent Rossiter-McLaughlin eect of the Earth eclipsing the Sun as seen from the Tycho crater and thereby confirm earlier observations. A small continuum polarization of the O_2_ A-band of 0.12% during umbral eclipse was detected at 6.3. No line polarization of the O_2_ A-band, or any other spectral-line feature, is detected outside nor inside eclipse. It places an upper limit of 0.2% on the degree of line polarization during transmission through Earth's atmosphere and magnetosphere.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/PAZh/38/15
- Title:
- Total-to-selective extinction ratio within 700pc
- Short Name:
- J/PAZh/38/15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Multicolor photometry from the Tycho-2 and 2MASS catalogues for 11990 OB (2008AstL...34....7G; 2012AstL...38..694G) and 30671 K-type red giant branch stars (2011AstL...37..707G) is used to detect systematic large-scale variations of the interstellar extinction law within the nearest kiloparsec. The characteristic of the extinction law, the total-to-selective extinction ratio Rv, which also characterizes the size and other properties of interstellar dust grains, has been calculated for various regions of space by the extinction law extrapolation method. The results for the two classes of stars agree: the standard deviation of the "red giants minus OB" Rv differences within 500pc of the Sun is 0.2. The detected Rv variations between 2.2 and 4.4 not only manifest themselves in individual clouds but also span the entire space near the Sun, following Galactic structures. In the Local Bubble within about 100 pc of the Sun, Rv has a minimum. In the inner part of the Gould Belt and at high Galactic latitudes, at a distance of about 150 pc from the Sun, Rv reaches a maximum and then decreases to its minimum in the outer part of the Belt and other directions at a distance of about 500 pc from the Sun, returning to its mean values far from the Sun. The detected maximum of Rv at high Galactic latitudes is important when allowance is made for the interstellar extinction toward extragalactic objects. In addition, a monotonic increase in Rv by 0.3 per kpc toward the Galactic center has been found near the Galactic equator. It is consistent with the result obtained by Zasowski et al. (2009ApJ...707..510Z) for much of the Galaxy. Ignoring the Rv variations and traditionally using a single value for the entire space must lead to systematic errors in the calculated distances reaching 10%.
- ID:
- ivo://CDS.VizieR/I/232
- Title:
- Toulouse AC Zone Data Reduced to ACRS
- Short Name:
- I/232
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The U.S. Naval Observatory is in the process of making new reductions of the Astrographic Catalogue (AC) using a modern reference system, the ACRS, which represents the system of the FK5. The data from the Toulouse Zone, whose plates are centered between declinations +5 and +11 degrees (eq. 1900), have been analyzed for scale, rotation, tilt, coma, magnitude equation, radial distortion and distortions introduced by the use of reseaux in the Carte du Ciel program. The result is a positional catalog of almost 270,000 stars on eq. J2000.0, epoch of observation. Additionally, all stars have been matched with the Tycho Input Catalog (revised); those numbers have been added for additional identification purposes.
- ID:
- ivo://CDS.VizieR/J/A+A/646/A113
- Title:
- Towards Cosmicflows-4 HI data catalog
- Short Name:
- J/A+A/646/A113
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this study, we present an update of a compilation of line width measurements of neutral atomic hydrogen (HI) galaxy spectra at 21 cm wavelength. Our All Digital HI (ADHI) catalog consists of the previous release augmented with our new HI observations and an analysis of archival data. This study provides the required HI information to measure the distances of spiral galaxies through the application of the Tully-Fisher (TF) relation. We conducted observations at the Green Bank telescope (GBT) and reprocessed spectra obtained at the Nancay radiotelescope by the Nancay Interstellar Baryons Legacy Extragalactic Survey (NIBLES) and Kinematics of the Local Universe (KLUN) collaborations and we analyzed the recently published full completion Arecibo Legacy Fast ALFA (ALFALFA) 100% survey in order to identify galaxies with good quality HI line width measurements. This paper adds new HI data adequate for TF use for 385 galaxies observed at GBT, 889 galaxies from archival Nancay spectra, and 1515 rescaled Arecibo ALFALFA spectra. In total, this release adds 1274 new good quality measurements to the ADHI catalog. Today, the ADHI database contains 18,874 galaxies, for which 15,433 have good quality data for TF use. The final goal is to compute accurate distances to spiral galaxies, which will be included in the next generation of peculiar velocities catalog: Cosmicflows-4. This paper adds new HI data adequate for TF use for 385 galaxies observed at GBT, 889 galaxies from archival Nancay spectra, and 1515 rescaled Arecibo ALFALFA spectra. In total, this release adds 1274 new good quality measurements to the ADHI catalog. Today, the ADHI database contains 18874 galaxies, for which 15433 have good quality data for TF use. The final goal is to compute accurate distances to spiral galaxies, which will be included in the next generation of peculiar velocities catalog: Cosmicflows-4.
- ID:
- ivo://CDS.VizieR/J/MNRAS/456/790
- Title:
- TP-AGB stars contribution in SFR
- Short Name:
- J/MNRAS/456/790
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the debated contribution from thermally pulsing asymptotic-giant-branch (TP-AGB) stars in evolutionary population synthesis models. We investigate the spectral energy distributions (SEDs) of a sample of 51 spectroscopically confirmed, high-z (1.3<z_spec_<2.7), galaxies using three evolutionary population synthesis models with strong, mild and light TP-AGB. Our sample is the largest of spectroscopically confirmed galaxies on which such models are tested so far. Galaxies were selected as passive, but we model them using a variety of star formation histories in order not to be dependent on this pre-selection. We find that the observed SEDs are best fitted with a significant contribution of TP-AGB stars or with substantial dust attenuation. Without including reddening, TP-AGB-strong models perform better and deliver solutions consistent within 1{sigma} from the best-fitted ones in the vast majority of cases. Including reddening, all models perform similarly. Using independent constraints from observations in the mid- and far-IR, we show that low/negligible dust attenuation, i.e. E(B-V)<~0.05, should be preferred for the SEDs of passively selected galaxies. Given that TP-AGB-light models give systematically older ages for passive galaxies, we suggest number counts of passive galaxies at higher redshifts as a further test to discriminate among stellar population models.
- ID:
- ivo://CDS.VizieR/J/A+A/622/A126
- Title:
- T Pyx 2011 outburst optical spectra
- Short Name:
- J/A+A/622/A126
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We aim to study the spectroscopic and ionized structural evolution of T Pyx during its 2011 outburst, and also study the variation in degree of polarization during its early phase. Optical spectroscopic data of this system obtained from day 1.28-2415.62 since discovery, and optical, broadband imaging polarimetric observations obtained from day 1.36-29.33 during the early phases of the outburst were used in the study. The physical conditions and the geometry of the ionized structure of the nova ejecta was modelled for a few epochs using the photo-ionization code, CLOUDY in 1D and pyCloudy in 3D. The spectral evolution of the nova ejecta during its 2011 outburst is similar to that of the previous outbursts. The variation in the line profiles is seen very clearly in the early stages due to good coverage during this period. The line profiles vary from P Cygni (narrower, deeper, and sharper) to emission profiles that are broader and structured, which later become narrower and sharper in the late post-outburst phase. The average ejected mass is estimated to be 7.03x10^-6^M_{sun}_. The ionized structure of the ejecta is found to be a bipolar conical structure with equatorial rings, with a low inclination angle of 14.75+/-0.65{deg}.
- ID:
- ivo://CDS.VizieR/J/MNRAS/403/1213
- Title:
- Tracers of stellar mass-loss. I.
- Short Name:
- J/MNRAS/403/1213
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present optical and IR integrated colours and SBF magnitudes, computed from stellar population synthesis models that include emission from the dusty envelopes surrounding TP-AGB stars undergoing mass-loss. We explore the effects of varying the mass-loss rate by one order of magnitude around the fiducial value, modifying accordingly both the stellar parameters and the output spectra of the TP-AGB stars plus their dusty envelopes. The models are single burst, and range in age from a few Myr to 14Gyr, and in metallicity between Z=0.0001 and Z=0.07; they combine new calculations for the evolution of stars in the TP-AGB phase, with star plus envelope SEDs produced with the radiative transfer code DUSTY. We compare these models to optical and near-IR data of single AGB stars and Magellanic star clusters. This comparison validates the current understanding of the role of mass-loss in determining stellar parameters and spectra in the TP-AGB. However, neither broad-band colours nor SBF measurements in the optical or the near-IR can discern global changes in the mass-loss rate of a stellar population. We predict that mid-IR SBF measurements can pick out such changes, and actually resolve whether a relation between metallicity and mass-loss exists.
- ID:
- ivo://CDS.VizieR/J/ApJ/856/170
- Title:
- Tracers of stellar mass-loss. II.
- Short Name:
- J/ApJ/856/170
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- I present integrated colors and surface brightness fluctuation magnitudes in the mid-infrared (IR), derived from stellar population synthesis models that include the effects of the dusty envelopes around thermally pulsing asymptotic giant branch (TP-AGB) stars. The models are based on the Bruzual & Charlot CB* isochrones; they are single-burst, range in age from a few Myr to 14Gyr, and comprise metallicities between Z=0.0001 and Z=0.04. I compare these models to mid-IR data of AGB stars and star clusters in the Magellanic Clouds, and study the effects of varying self-consistently the mass-loss rate, the stellar parameters, and the output spectra of the stars plus their dusty envelopes. I find that models with a higher than fiducial mass-loss rate are needed to fit the mid-IR colors of "extreme" single AGB stars in the Large Magellanic Cloud. Surface brightness fluctuation magnitudes are quite sensitive to metallicity for 4.5{mu}m and longer wavelengths at all stellar population ages, and powerful diagnostics of mass-loss rate in the TP-AGB for intermediate-age populations, between 100Myr and 2-3Gyr.
- ID:
- ivo://CDS.VizieR/J/A+A/562/A134
- Title:
- Tracers of the Milky Way mass
- Short Name:
- J/A+A/562/A134
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We model the phase-space distribution of the kinematic tracers using general, smooth distribution functions to derive a conservative lower bound on the total mass within ~~150-200kpc. By approximating the potential as Keplerian, the phase-space distribution can be simplified to that of a smooth distribution of energies and eccentricities. Our approach naturally allows for calculating moments of the distribution function, such as the radial profile of the orbital anisotropy. We systematically construct a family of phase-space functions with the resulting radial velocity dispersion overlapping with the one obtained using data on radial motions of distant kinematic tracers, while making no assumptions about the density of the tracers and the velocity anisotropy parameter {beta} regarded as a function of the radial variable. While there is no apparent upper bound for the Milky Way mass, at least as long as only the radial motions are concerned, we find a sharp lower bound for the mass that is small. In particular, a mass value of 2.4x10^11^M_{sun}_, obtained in the past for lower and intermediate radii, is still consistent with the dispersion profile at larger radii. Compared with much greater mass values in the literature, this result shows that determining the Milky Way mass is strongly model-dependent. We expect a similar reduction of mass estimates in models assuming more realistic mass profiles.
- ID:
- ivo://CDS.VizieR/J/A+A/609/A53
- Title:
- Tracing stars of MW dwarf galaxies: Sextans
- Short Name:
- J/A+A/609/A53
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a deep and very spatially extended CTIO/DECam g and r photometric catalogue of point-sources (reaching out to ~2 magnitudes below the oldest main-sequence turn-off and covering ~20deg^2^) around the Sextans dwarf spheroidal galaxy, together with another catalogue of literature spectroscopic measurements (Walker et al., 2009, Cat. J/AJ/137/3100 and Battaglia et al., 2011, Cat. J/MNRAS/411/1013) with updated membership probabilities.
