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- ID:
- ivo://CDS.VizieR/J/A+A/523/A58
- Title:
- PDF Atlas and spectra of FeH molecule in LHS 2
- Short Name:
- J/A+A/523/A58
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an atlas for the iron-hydride molecule (FeH) in the z-range (990nm to 1076.6nm). We used high-resolution CRIRES spectra of the M-dwarf GJ1002, which is an ideal target for the investigation of FeH, because it is only very slow rotating (<3km/s) and exhibits only weak magnetic fields. The identified lines stem mainly from the (0-0) and (1-1) vibronic transitions, but also from the (1-0), (2-1), (2-2), (3-2), and (4-3) transitions. For the confirmation of the identifications, we used means of statistic and cross-correlation as well as the line intensities. We corrected the theoretical positions if needed and scaled the line intensities till they match the observations.
1943. PDS70 VLT/SPHERE images
- ID:
- ivo://CDS.VizieR/J/A+A/632/A25
- Title:
- PDS70 VLT/SPHERE images
- Short Name:
- J/A+A/632/A25
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- PDS 70 is a young (5.4Myr), nearby (~113pc) star hosting a known transition disk with a large gap. Recent observations with SPHERE and NACO in the near-infrared (NIR) allowed us to detect a planetary mass companion, PDS70b, within the disk cavity. Moreover, observations in H{alpha} with MagAO and MUSE revealed emission associated to PDS 70 b and to another new companion candidate, PDS70c, at a larger separation from the star. PDS 70 is the only multiple planetary system at its formation stage detected so far through direct imaging. Our aim is to confirm the discovery of the second planet PDS 70 c using SPHERE at VLT, to further characterize its physical properties, and search for additional point sources in this young planetary system. Methods. We re-analyzed archival SPHERE NIR observations and obtained new data in Y, J, H and K spectral bands for a total of four different epochs. The data were reduced using the data reduction and handling pipeline and the SPHERE data center. We then applied custom routines (e.g. ANDROMEDA and PACO) to subtract the starlight. We re-detect both PDS 70 b and c and confirm that PDS70c is gravitationally bound to the star. We estimate this second planet to be less massive than 5M_Jup_ and with a Teff around 900K. Also, it has a low gravity with log g between 3.0 and 3.5dex. In addition, a third object has been identified at short separation (~0.12") from the star and gravitationally bound to the star. Its spectrum is however very blue, so that we are probably seeing stellar light reflected by dust and our analysis seems to demonstrate that it is a feature of the inner disk. We, however, cannot completely exclude the possibility that it is a planetary mass object enshrouded by a dust envelope. In this latter case, its mass should be of the order of few tens of M_{Earth}_. Moreover, we propose a possible structure for the planetary system based on our data that, however, cannot be stable on a long timescale.
- ID:
- ivo://CDS.VizieR/J/AJ/135/1624
- Title:
- PEARS emission-line galaxies
- Short Name:
- J/AJ/135/1624
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Hubble Space Telescope Advanced Camera for Surveys grism Probing Evolution And Reionization Spectroscopically (PEARS) survey provides a large dataset of low-resolution spectra from thousands of galaxies in the GOODS north and south fields. One important subset of objects in these data is emission-line galaxies (ELGs), and we have investigated several different methods aimed at systematically selecting these galaxies. Here, we present a new methodology and results of a search for these ELGs in the PEARS observations of the Hubble Ultra Deep Field (HUDF) using a 2D detection method that utilizes the observation that many emission lines originate from clumpy knots within galaxies. This 2D line-finding method proves to be useful in detecting emission lines from compact knots within galaxies that might not otherwise be detected using more traditional 1D line-finding techniques.
- ID:
- ivo://CDS.VizieR/J/AJ/141/64
- Title:
- PEARS emission-line galaxies spectroscopy
- Short Name:
- J/AJ/141/64
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present spectroscopy of 76 emission-line galaxies (ELGs) in Chandra Deep Field South taken with the LDSS3 spectrograph on the Magellan Telescope. These galaxies are selected because they have emission lines with the Advanced Camera for Surveys (ACS) grism data in the Hubble Space Telescope Probing Evolution and Reionization Spectroscopically (PEARS) grism Survey. The ACS grism spectra cover the wavelength range 6000-9700{AA} and most PEARS grism redshifts are based on a single emission line + photometric redshifts from broadband colors; the Magellan spectra cover a wavelength range from 4000{AA} to 9000{AA} and provide a check on redshifts derived from PEARS data.
- ID:
- ivo://CDS.VizieR/J/ApJ/793/132
- Title:
- Perseus cloud sources Gaussian parameters
- Short Name:
- J/ApJ/793/132
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using the Arecibo Observatory, we have obtained neutral hydrogen (HI) absorption and emission spectral pairs in the direction of 26 background radio continuum sources in the vicinity of the Perseus molecular cloud. Strong absorption lines were detected in all cases, allowing us to estimate spin temperature (T_s_) and optical depth for 107 individual Gaussian components along these lines of sight. Basic properties of individual H I clouds (spin temperature, optical depth, and the column density of the cold and warm neutral medium (CNM and WNM), respectively) in and around Perseus are very similar to those found for random interstellar lines of sight sampled by the Millennium H I survey. This suggests that the neutral gas found in and around molecular clouds is not atypical. However, lines of sight in the vicinity of Perseus have, on average, a higher total H I column density and the CNM fraction, suggesting an enhanced amount of cold H I relative to an average interstellar field. Our estimated optical depth and spin temperature are in stark contrast with the recent attempt at using Planck data to estimate properties of the optically thick H I. Only ~15% of lines of sight in our study have a column density weighted average spin temperature lower than 50 K, in comparison with >~85% of Planck's sky coverage. The observed CNM fraction is inversely proportional to the optical depth weighted average spin temperature, in excellent agreement with the recent numerical simulations by Kim et al. (2014ApJ...786...64K). While the CNM fraction is, on average, higher around Perseus relative to a random interstellar field, it is generally low, between 10%-50%. This suggests that extended WNM envelopes around molecular clouds and/or significant mixing of CNM and WNM throughout molecular clouds are present and should be considered in the models of molecule and star formation. Our detailed comparison of H I absorption with CO emission spectra shows that only 3 of the 26 directions are clear candidates for probing the CO-dark gas as they have N(H I)>10^21^/cm2 yet no detectable CO emission.
- ID:
- ivo://CDS.VizieR/J/A+A/659/A13
- Title:
- PG 2130+099 narrowband light curves
- Short Name:
- J/A+A/659/A13
- Date:
- 25 Feb 2022 07:32:33
- Publisher:
- CDS
- Description:
- We present the results of an intensive six-month optical continuum reverberation mapping campaign of the Seyfert 1 galaxy PG 2130+099 at redshift z=0.063. The ground- based photometric monitoring was conducted on a daily basis with the robotic 46cm telescope of the Wise observatory located in Israel. Specially designed narrowband filters were used to observe the central engine of the active galactic nucleus (AGN), avoiding line contamination from the broad-line region (BLR). We aim to measure inter- band continuum time lags across the optical range and determine the size-wavelength relation for this system. PG 2130+099 displays correlated variability across the optical range, and we successfully detect significant time lags of up to 3 days between the multiband light curves. While a continuum reprocessing model can fit the data reasonably well, our derived disk sizes are a factor of 2-6 larger than the theoretical disk sizes predicted from the AGN luminosity estimate of PG 2130+099. This result is in agreement with previous studies of AGN/quasars and suggests that the standard Shakura- Sunyaev disk theory has limitations in describing AGN accretion disks.
1948. phi Leo spectra
- ID:
- ivo://CDS.VizieR/J/A+A/653/A115
- Title:
- phi Leo spectra
- Short Name:
- J/A+A/653/A115
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- Variable red- and blue-shifted absorption features observed in the CaII K line towards the A-type shell star {phi} Leo have been suggested by us in a previous work to be likely due to solid, comet-like bodies in the circumstellar (CS) environment. Our aim is to expand our observational study of this object to other characteristic spectral lines of A-type photospheres as well as to lines arising in their CS shells. We have obtained more than 500 high-resolution optical spectra collected at different telescopes during 37 nights in several observing runs from December 2015 to January 2019. Time series consecutive spectra were taken, covering intervals of up to ~9 hours in some nights. We have analysed some photospheric lines, in particular CaI 4226{AA} and MgII 4481{AA}, as well as the circumstellar shell lines CaII H&K, CaII IR triplet, FeII 4924, 5018 and 5169{AA}, TiII 3685, 3759 and 3761{AA}, and the Balmer lines H{alpha} and H{beta}. Our observational study reveals that {phi} Leo is a variable delta Scuti star whose spectra show remarkable dumps and bumps superimposed on the photospheric line profiles, which vary their strength and sharpness, propagate from blue- to more red-shifted radial velocities and persisting during a few hours. Similarly t o other delta Scuti stars, these features are likely produced by non-radial pulsations. At the same time, all shell lines present an emission at ~3km/s centered at the core of the CS features, and two variable absorption minima at both sides of the emission; those absorption minima occur at practically the same velocity for each line, i.e., no apparent dynamical evolution is observed. The variations observed in the CaII H&K, FeII and TiII lines occur at any time scale from minutes to days and observing run, but without any clear correlation or recognizable temporal pattern among the different lines. In the case of H{alpha} the CS contribution is also variable in just one of the observing runs. Summarizing, we suggest that {phi} Leo is a rapidly rotating delta Scuti star surrounded by a variable, (nearly) edge-on CS disk possibly re-supplied by the delta Scuti pulsations. The behaviour of the CS shell lines is reminiscent of the one observed in rapidly rotating Be shell stars with an edge-on CS disk, and clearly points out that the variations observed in the CS features of {phi} Leo are highly unlikely to be produced by exocomets. In addition, the observational results presented in this work, together with some recent results concerning the shell star HR 10, suggest the need of a critical revision of the CaII K features which have been attributed to exocomets in other shell stars.
- ID:
- ivo://CDS.VizieR/J/ApJ/624/135
- Title:
- Phoenix Deep Survey spectroscopic catalog
- Short Name:
- J/ApJ/624/135
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Phoenix Deep Survey is a multiwavelength survey based on deep 1.4GHz radio imaging, reaching well into the sub-100uJy level. One of the aims of this survey is to characterize the submillijansky radio population, exploring its nature and evolution. In this paper we present the catalog and results of the spectroscopic observations aimed at characterizing the optically "bright" (R<~21.5mag) counterparts of faint radio sources. Of 371 sources with redshift determination, 21% have absorption lines only, 11% show active galactic nucleus signatures, 32% are star-forming galaxies, 34% show narrow emission lines that do not allow detailed spectral classification (owing to poor signal-to-noise ratio and/or lack of diagnostic emission lines), and the remaining 2% are identified with stars.
- ID:
- ivo://CDS.VizieR/J/MNRAS/466/2006
- Title:
- Phoenix dwarf galaxy RV and [Fe/H] catalog
- Short Name:
- J/MNRAS/466/2006
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Transition type dwarf galaxies are thought to be systems undergoing the process of transformation from a star-forming into a passively evolving dwarf, which makes them particularly suitable to study evolutionary processes driving the existence of different dwarf morphological types. Here we present results from a spectroscopic survey of ~200 individual red giant branch stars in the Phoenix dwarf, the closest transition type with a comparable luminosity to 'classical' dwarf galaxies. We measure a systemic heliocentric velocity Vhelio=-21.2+/-1.0km/s. Our survey reveals the clear presence of prolate rotation that is aligned with the peculiar spatial distribution of the youngest stars in Phoenix. We speculate that both features might have arisen from the same event, possibly an accretion of a smaller system. The evolved stellar population of Phoenix is relatively metal-poor (<[Fe/H]>=-1.49+/-0.04dex) and shows a large metallicity spread (sigma_[Fe/H]_=0.51+/-0.04dex), with a pronounced metallicity gradient of -0.13+/-0.01dex/arcmin similar to luminous, passive dwarf galaxies. We also report a discovery of an extremely metal-poor star candidate in Phoenix and discuss the importance of correcting for spatial sampling when interpreting the chemical properties of galaxies with metallicity gradients. This study presents a major leap forward in our knowledge of the internal kinematics of the Phoenix transition type dwarf galaxy and the first wide area spectroscopic survey of its metallicity properties.
